Commit Graph

5775 Commits

Author SHA1 Message Date
Mohamed Khalfella
4b8b390516 tracing/histograms: Return an error if we fail to add histogram to hist_vars list
Commit 6018b585e8 ("tracing/histograms: Add histograms to hist_vars if
they have referenced variables") added a check to fail histogram creation
if save_hist_vars() failed to add histogram to hist_vars list. But the
commit failed to set ret to failed return code before jumping to
unregister histogram, fix it.

Link: https://lore.kernel.org/linux-trace-kernel/20230714203341.51396-1-mkhalfella@purestorage.com

Cc: stable@vger.kernel.org
Fixes: 6018b585e8 ("tracing/histograms: Add histograms to hist_vars if they have referenced variables")
Signed-off-by: Mohamed Khalfella <mkhalfella@purestorage.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-23 11:18:52 -04:00
Chen Lin
8a96c0288d ring-buffer: Do not swap cpu_buffer during resize process
When ring_buffer_swap_cpu was called during resize process,
the cpu buffer was swapped in the middle, resulting in incorrect state.
Continuing to run in the wrong state will result in oops.

This issue can be easily reproduced using the following two scripts:
/tmp # cat test1.sh
//#! /bin/sh
for i in `seq 0 100000`
do
         echo 2000 > /sys/kernel/debug/tracing/buffer_size_kb
         sleep 0.5
         echo 5000 > /sys/kernel/debug/tracing/buffer_size_kb
         sleep 0.5
done
/tmp # cat test2.sh
//#! /bin/sh
for i in `seq 0 100000`
do
        echo irqsoff > /sys/kernel/debug/tracing/current_tracer
        sleep 1
        echo nop > /sys/kernel/debug/tracing/current_tracer
        sleep 1
done
/tmp # ./test1.sh &
/tmp # ./test2.sh &

A typical oops log is as follows, sometimes with other different oops logs.

[  231.711293] WARNING: CPU: 0 PID: 9 at kernel/trace/ring_buffer.c:2026 rb_update_pages+0x378/0x3f8
[  231.713375] Modules linked in:
[  231.714735] CPU: 0 PID: 9 Comm: kworker/0:1 Tainted: G        W          6.5.0-rc1-00276-g20edcec23f92 #15
[  231.716750] Hardware name: linux,dummy-virt (DT)
[  231.718152] Workqueue: events update_pages_handler
[  231.719714] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  231.721171] pc : rb_update_pages+0x378/0x3f8
[  231.722212] lr : rb_update_pages+0x25c/0x3f8
[  231.723248] sp : ffff800082b9bd50
[  231.724169] x29: ffff800082b9bd50 x28: ffff8000825f7000 x27: 0000000000000000
[  231.726102] x26: 0000000000000001 x25: fffffffffffff010 x24: 0000000000000ff0
[  231.728122] x23: ffff0000c3a0b600 x22: ffff0000c3a0b5c0 x21: fffffffffffffe0a
[  231.730203] x20: ffff0000c3a0b600 x19: ffff0000c0102400 x18: 0000000000000000
[  231.732329] x17: 0000000000000000 x16: 0000000000000000 x15: 0000ffffe7aa8510
[  231.734212] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000002
[  231.736291] x11: ffff8000826998a8 x10: ffff800082b9baf0 x9 : ffff800081137558
[  231.738195] x8 : fffffc00030e82c8 x7 : 0000000000000000 x6 : 0000000000000001
[  231.740192] x5 : ffff0000ffbafe00 x4 : 0000000000000000 x3 : 0000000000000000
[  231.742118] x2 : 00000000000006aa x1 : 0000000000000001 x0 : ffff0000c0007208
[  231.744196] Call trace:
[  231.744892]  rb_update_pages+0x378/0x3f8
[  231.745893]  update_pages_handler+0x1c/0x38
[  231.746893]  process_one_work+0x1f0/0x468
[  231.747852]  worker_thread+0x54/0x410
[  231.748737]  kthread+0x124/0x138
[  231.749549]  ret_from_fork+0x10/0x20
[  231.750434] ---[ end trace 0000000000000000 ]---
[  233.720486] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[  233.721696] Mem abort info:
[  233.721935]   ESR = 0x0000000096000004
[  233.722283]   EC = 0x25: DABT (current EL), IL = 32 bits
[  233.722596]   SET = 0, FnV = 0
[  233.722805]   EA = 0, S1PTW = 0
[  233.723026]   FSC = 0x04: level 0 translation fault
[  233.723458] Data abort info:
[  233.723734]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[  233.724176]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[  233.724589]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[  233.725075] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000104943000
[  233.725592] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
[  233.726231] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[  233.726720] Modules linked in:
[  233.727007] CPU: 0 PID: 9 Comm: kworker/0:1 Tainted: G        W          6.5.0-rc1-00276-g20edcec23f92 #15
[  233.727777] Hardware name: linux,dummy-virt (DT)
[  233.728225] Workqueue: events update_pages_handler
[  233.728655] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  233.729054] pc : rb_update_pages+0x1a8/0x3f8
[  233.729334] lr : rb_update_pages+0x154/0x3f8
[  233.729592] sp : ffff800082b9bd50
[  233.729792] x29: ffff800082b9bd50 x28: ffff8000825f7000 x27: 0000000000000000
[  233.730220] x26: 0000000000000000 x25: ffff800082a8b840 x24: ffff0000c0102418
[  233.730653] x23: 0000000000000000 x22: fffffc000304c880 x21: 0000000000000003
[  233.731105] x20: 00000000000001f4 x19: ffff0000c0102400 x18: ffff800082fcbc58
[  233.731727] x17: 0000000000000000 x16: 0000000000000001 x15: 0000000000000001
[  233.732282] x14: ffff8000825fe0c8 x13: 0000000000000001 x12: 0000000000000000
[  233.732709] x11: ffff8000826998a8 x10: 0000000000000ae0 x9 : ffff8000801b760c
[  233.733148] x8 : fefefefefefefeff x7 : 0000000000000018 x6 : ffff0000c03298c0
[  233.733553] x5 : 0000000000000002 x4 : 0000000000000000 x3 : 0000000000000000
[  233.733972] x2 : ffff0000c3a0b600 x1 : 0000000000000000 x0 : 0000000000000000
[  233.734418] Call trace:
[  233.734593]  rb_update_pages+0x1a8/0x3f8
[  233.734853]  update_pages_handler+0x1c/0x38
[  233.735148]  process_one_work+0x1f0/0x468
[  233.735525]  worker_thread+0x54/0x410
[  233.735852]  kthread+0x124/0x138
[  233.736064]  ret_from_fork+0x10/0x20
[  233.736387] Code: 92400000 910006b5 aa000021 aa0303f7 (f9400060)
[  233.736959] ---[ end trace 0000000000000000 ]---

After analysis, the seq of the error is as follows [1-5]:

int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
			int cpu_id)
{
	for_each_buffer_cpu(buffer, cpu) {
		cpu_buffer = buffer->buffers[cpu];
		//1. get cpu_buffer, aka cpu_buffer(A)
		...
		...
		schedule_work_on(cpu,
		 &cpu_buffer->update_pages_work);
		//2. 'update_pages_work' is queue on 'cpu', cpu_buffer(A) is passed to
		// update_pages_handler, do the update process, set 'update_done' in
		// complete(&cpu_buffer->update_done) and to wakeup resize process.
	//---->
		//3. Just at this moment, ring_buffer_swap_cpu is triggered,
		//cpu_buffer(A) be swaped to cpu_buffer(B), the max_buffer.
		//ring_buffer_swap_cpu is called as the 'Call trace' below.

		Call trace:
		 dump_backtrace+0x0/0x2f8
		 show_stack+0x18/0x28
		 dump_stack+0x12c/0x188
		 ring_buffer_swap_cpu+0x2f8/0x328
		 update_max_tr_single+0x180/0x210
		 check_critical_timing+0x2b4/0x2c8
		 tracer_hardirqs_on+0x1c0/0x200
		 trace_hardirqs_on+0xec/0x378
		 el0_svc_common+0x64/0x260
		 do_el0_svc+0x90/0xf8
		 el0_svc+0x20/0x30
		 el0_sync_handler+0xb0/0xb8
		 el0_sync+0x180/0x1c0
	//<----

	/* wait for all the updates to complete */
	for_each_buffer_cpu(buffer, cpu) {
		cpu_buffer = buffer->buffers[cpu];
		//4. get cpu_buffer, cpu_buffer(B) is used in the following process,
		//the state of cpu_buffer(A) and cpu_buffer(B) is totally wrong.
		//for example, cpu_buffer(A)->update_done will leave be set 1, and will
		//not 'wait_for_completion' at the next resize round.
		  if (!cpu_buffer->nr_pages_to_update)
			continue;

		if (cpu_online(cpu))
			wait_for_completion(&cpu_buffer->update_done);
		cpu_buffer->nr_pages_to_update = 0;
	}
	...
}
	//5. the state of cpu_buffer(A) and cpu_buffer(B) is totally wrong,
	//Continuing to run in the wrong state, then oops occurs.

Link: https://lore.kernel.org/linux-trace-kernel/202307191558478409990@zte.com.cn

Signed-off-by: Chen Lin <chen.lin5@zte.com.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-23 11:09:25 -04:00
YueHaibing
1faf7e4a0b tracing: Remove unused extern declaration tracing_map_set_field_descr()
Since commit 08d43a5fa0 ("tracing: Add lock-free tracing_map"),
this is never used, so can be removed.

Link: https://lore.kernel.org/linux-trace-kernel/20230722032123.24664-1-yuehaibing@huawei.com

Cc: <mhiramat@kernel.org>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-23 11:08:14 -04:00
Linus Torvalds
4b4eef57e6 Probe fixes for 6.5-rc1, the 2nd set:
- fprobe: Add a comment why fprobe will be skipped if another kprobe is
    running in fprobe_kprobe_handler().
 
  - probe-events: Fix some issues related to fetch-argument
   . Fix double counting of the string length for user-string and symstr.
     This will require longer buffer in the array case.
   . Fix not to count error code (minus value) for the total used length
     in array argument. This makes the total used length shorter.
   . Fix to update dynamic used data size counter only if fetcharg uses
     the dynamic size data. This may mis-count the used dynamic data
     size and corrupt data.
   . Revert "tracing: Add "(fault)" name injection to kernel probes"
     because that did not work correctly with a bug, and we agreed the
     current '(fault)' output (instead of '"(fault)"' like a string)
     explains what happened more clearly.
   . Fix to record 0-length (means fault access) data_loc data in fetch
     function itself, instead of store_trace_args(). If we record an
     array of string, this will fix to save fault access data on each
     entry of the array correctly.
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Merge tag 'probes-fixes-v6.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull probe fixes from Masami Hiramatsu:

 - fprobe: Add a comment why fprobe will be skipped if another kprobe is
   running in fprobe_kprobe_handler().

 - probe-events: Fix some issues related to fetch-arguments:

    - Fix double counting of the string length for user-string and
      symstr. This will require longer buffer in the array case.

    - Fix not to count error code (minus value) for the total used
      length in array argument. This makes the total used length
      shorter.

    - Fix to update dynamic used data size counter only if fetcharg uses
      the dynamic size data. This may mis-count the used dynamic data
      size and corrupt data.

    - Revert "tracing: Add "(fault)" name injection to kernel probes"
      because that did not work correctly with a bug, and we agreed the
      current '(fault)' output (instead of '"(fault)"' like a string)
      explains what happened more clearly.

    - Fix to record 0-length (means fault access) data_loc data in fetch
      function itself, instead of store_trace_args(). If we record an
      array of string, this will fix to save fault access data on each
      entry of the array correctly.

* tag 'probes-fixes-v6.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/probes: Fix to record 0-length data_loc in fetch_store_string*() if fails
  Revert "tracing: Add "(fault)" name injection to kernel probes"
  tracing/probes: Fix to update dynamic data counter if fetcharg uses it
  tracing/probes: Fix not to count error code to total length
  tracing/probes: Fix to avoid double count of the string length on the array
  fprobes: Add a comment why fprobe_kprobe_handler exits if kprobe is running
2023-07-16 12:13:51 -07:00
Masami Hiramatsu (Google)
797311bce5 tracing/probes: Fix to record 0-length data_loc in fetch_store_string*() if fails
Fix to record 0-length data to data_loc in fetch_store_string*() if it fails
to get the string data.
Currently those expect that the data_loc is updated by store_trace_args() if
it returns the error code. However, that does not work correctly if the
argument is an array of strings. In that case, store_trace_args() only clears
the first entry of the array (which may have no error) and leaves other
entries. So it should be cleared by fetch_store_string*() itself.
Also, 'dyndata' and 'maxlen' in store_trace_args() should be updated
only if it is used (ret > 0 and argument is a dynamic data.)

Link: https://lore.kernel.org/all/168908496683.123124.4761206188794205601.stgit@devnote2/

Fixes: 40b53b7718 ("tracing: probeevent: Add array type support")
Cc: stable@vger.kernel.org
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-14 17:04:58 +09:00
Linus Torvalds
ebc27aacee Tracing fixes and clean ups:
- Fix some missing-prototype warnings
 
 - Fix user events struct args (did not include size of struct)
   When creating a user event, the "struct" keyword is to denote
   that the size of the field will be passed in. But the parsing
   failed to handle this case.
 
 - Add selftest to struct sizes for user events
 
 - Fix sample code for direct trampolines.
   The sample code for direct trampolines attached to handle_mm_fault().
   But the prototype changed and the direct trampoline sample code
   was not updated. Direct trampolines needs to have the arguments correct
   otherwise it can fail or crash the system.
 
 - Remove unused ftrace_regs_caller_ret() prototype.
 
 - Quiet false positive of FORTIFY_SOURCE
   Due to backward compatibility, the structure used to save stack traces
   in the kernel had a fixed size of 8. This structure is exported to
   user space via the tracing format file. A change was made to allow
   more than 8 functions to be recorded, and user space now uses the
   size field to know how many functions are actually in the stack.
   But the structure still has size of 8 (even though it points into
   the ring buffer that has the required amount allocated to hold a
   full stack. This was fine until the fortifier noticed that the
   memcpy(&entry->caller, stack, size) was greater than the 8 functions
   and would complain at runtime about it. Hide this by using a pointer
   to the stack location on the ring buffer instead of using the address
   of the entry structure caller field.
 
 - Fix a deadloop in reading trace_pipe that was caused by a mismatch
   between ring_buffer_empty() returning false which then asked to
   read the data, but the read code uses rb_num_of_entries() that
   returned zero, and causing a infinite "retry".
 
 - Fix a warning caused by not using all pages allocated to store
   ftrace functions, where this can happen if the linker inserts a bunch of
   "NULL" entries, causing the accounting of how many pages needed
   to be off.
 
 - Fix histogram synthetic event crashing when the start event is
   removed and the end event is still using a variable from it.
 
 - Fix memory leak in freeing iter->temp in tracing_release_pipe()
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Merge tag 'trace-v6.5-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix some missing-prototype warnings

 - Fix user events struct args (did not include size of struct)

   When creating a user event, the "struct" keyword is to denote that
   the size of the field will be passed in. But the parsing failed to
   handle this case.

 - Add selftest to struct sizes for user events

 - Fix sample code for direct trampolines.

   The sample code for direct trampolines attached to handle_mm_fault().
   But the prototype changed and the direct trampoline sample code was
   not updated. Direct trampolines needs to have the arguments correct
   otherwise it can fail or crash the system.

 - Remove unused ftrace_regs_caller_ret() prototype.

 - Quiet false positive of FORTIFY_SOURCE

   Due to backward compatibility, the structure used to save stack
   traces in the kernel had a fixed size of 8. This structure is
   exported to user space via the tracing format file. A change was made
   to allow more than 8 functions to be recorded, and user space now
   uses the size field to know how many functions are actually in the
   stack.

   But the structure still has size of 8 (even though it points into the
   ring buffer that has the required amount allocated to hold a full
   stack.

   This was fine until the fortifier noticed that the
   memcpy(&entry->caller, stack, size) was greater than the 8 functions
   and would complain at runtime about it.

   Hide this by using a pointer to the stack location on the ring buffer
   instead of using the address of the entry structure caller field.

 - Fix a deadloop in reading trace_pipe that was caused by a mismatch
   between ring_buffer_empty() returning false which then asked to read
   the data, but the read code uses rb_num_of_entries() that returned
   zero, and causing a infinite "retry".

 - Fix a warning caused by not using all pages allocated to store ftrace
   functions, where this can happen if the linker inserts a bunch of
   "NULL" entries, causing the accounting of how many pages needed to be
   off.

 - Fix histogram synthetic event crashing when the start event is
   removed and the end event is still using a variable from it

 - Fix memory leak in freeing iter->temp in tracing_release_pipe()

* tag 'trace-v6.5-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Fix memory leak of iter->temp when reading trace_pipe
  tracing/histograms: Add histograms to hist_vars if they have referenced variables
  tracing: Stop FORTIFY_SOURCE complaining about stack trace caller
  ftrace: Fix possible warning on checking all pages used in ftrace_process_locs()
  ring-buffer: Fix deadloop issue on reading trace_pipe
  tracing: arm64: Avoid missing-prototype warnings
  selftests/user_events: Test struct size match cases
  tracing/user_events: Fix struct arg size match check
  x86/ftrace: Remove unsued extern declaration ftrace_regs_caller_ret()
  arm64: ftrace: Add direct call trampoline samples support
  samples: ftrace: Save required argument registers in sample trampolines
2023-07-13 13:44:28 -07:00
Masami Hiramatsu (Google)
4ed8f337de Revert "tracing: Add "(fault)" name injection to kernel probes"
This reverts commit 2e9906f84f.

It was turned out that commit 2e9906f84f ("tracing: Add "(fault)"
name injection to kernel probes") did not work correctly and probe
events still show just '(fault)' (instead of '"(fault)"'). Also,
current '(fault)' is more explicit that it faulted.

This also moves FAULT_STRING macro to trace.h so that synthetic
event can keep using it, and uses it in trace_probe.c too.

Link: https://lore.kernel.org/all/168908495772.123124.1250788051922100079.stgit@devnote2/
Link: https://lore.kernel.org/all/20230706230642.3793a593@rorschach.local.home/

Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-14 00:37:43 +09:00
Masami Hiramatsu (Google)
e38e2c6a9e tracing/probes: Fix to update dynamic data counter if fetcharg uses it
Fix to update dynamic data counter ('dyndata') and max length ('maxlen')
only if the fetcharg uses the dynamic data. Also get out arg->dynamic
from unlikely(). This makes dynamic data address wrong if
process_fetch_insn() returns error on !arg->dynamic case.

Link: https://lore.kernel.org/all/168908494781.123124.8160245359962103684.stgit@devnote2/

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Link: https://lore.kernel.org/all/20230710233400.5aaf024e@gandalf.local.home/
Fixes: 9178412ddf ("tracing: probeevent: Return consumed bytes of dynamic area")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-14 00:37:00 +09:00
Masami Hiramatsu (Google)
b41326b5e0 tracing/probes: Fix not to count error code to total length
Fix not to count the error code (which is minus value) to the total
used length of array, because it can mess up the return code of
process_fetch_insn_bottom(). Also clear the 'ret' value because it
will be used for calculating next data_loc entry.

Link: https://lore.kernel.org/all/168908493827.123124.2175257289106364229.stgit@devnote2/

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/8819b154-2ba1-43c3-98a2-cbde20892023@moroto.mountain/
Fixes: 9b960a3883 ("tracing: probeevent: Unify fetch_insn processing common part")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-14 00:36:28 +09:00
Masami Hiramatsu (Google)
66bcf65d6c tracing/probes: Fix to avoid double count of the string length on the array
If an array is specified with the ustring or symstr, the length of the
strings are accumlated on both of 'ret' and 'total', which means the
length is double counted.
Just set the length to the 'ret' value for avoiding double counting.

Link: https://lore.kernel.org/all/168908492917.123124.15076463491122036025.stgit@devnote2/

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/8819b154-2ba1-43c3-98a2-cbde20892023@moroto.mountain/
Fixes: 88903c4643 ("tracing/probe: Add ustring type for user-space string")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-14 00:35:53 +09:00
Masami Hiramatsu (Google)
d5f28bb1ce fprobes: Add a comment why fprobe_kprobe_handler exits if kprobe is running
Add a comment the reason why fprobe_kprobe_handler() exits if any other
kprobe is running.

Link: https://lore.kernel.org/all/168874788299.159442.2485957441413653858.stgit@devnote2/

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Link: https://lore.kernel.org/all/20230706120916.3c6abf15@gandalf.local.home/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-14 00:24:00 +09:00
Zheng Yejian
d5a8218963 tracing: Fix memory leak of iter->temp when reading trace_pipe
kmemleak reports:
  unreferenced object 0xffff88814d14e200 (size 256):
    comm "cat", pid 336, jiffies 4294871818 (age 779.490s)
    hex dump (first 32 bytes):
      04 00 01 03 00 00 00 00 08 00 00 00 00 00 00 00  ................
      0c d8 c8 9b ff ff ff ff 04 5a ca 9b ff ff ff ff  .........Z......
    backtrace:
      [<ffffffff9bdff18f>] __kmalloc+0x4f/0x140
      [<ffffffff9bc9238b>] trace_find_next_entry+0xbb/0x1d0
      [<ffffffff9bc9caef>] trace_print_lat_context+0xaf/0x4e0
      [<ffffffff9bc94490>] print_trace_line+0x3e0/0x950
      [<ffffffff9bc95499>] tracing_read_pipe+0x2d9/0x5a0
      [<ffffffff9bf03a43>] vfs_read+0x143/0x520
      [<ffffffff9bf04c2d>] ksys_read+0xbd/0x160
      [<ffffffff9d0f0edf>] do_syscall_64+0x3f/0x90
      [<ffffffff9d2000aa>] entry_SYSCALL_64_after_hwframe+0x6e/0xd8

when reading file 'trace_pipe', 'iter->temp' is allocated or relocated
in trace_find_next_entry() but not freed before 'trace_pipe' is closed.

To fix it, free 'iter->temp' in tracing_release_pipe().

Link: https://lore.kernel.org/linux-trace-kernel/20230713141435.1133021-1-zhengyejian1@huawei.com

Cc: stable@vger.kernel.org
Fixes: ff895103a8 ("tracing: Save off entry when peeking at next entry")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-13 10:48:36 -04:00
Mohamed Khalfella
6018b585e8 tracing/histograms: Add histograms to hist_vars if they have referenced variables
Hist triggers can have referenced variables without having direct
variables fields. This can be the case if referenced variables are added
for trigger actions. In this case the newly added references will not
have field variables. Not taking such referenced variables into
consideration can result in a bug where it would be possible to remove
hist trigger with variables being refenced. This will result in a bug
that is easily reproducable like so

$ cd /sys/kernel/tracing
$ echo 'synthetic_sys_enter char[] comm; long id' >> synthetic_events
$ echo 'hist:keys=common_pid.execname,id.syscall:vals=hitcount:comm=common_pid.execname' >> events/raw_syscalls/sys_enter/trigger
$ echo 'hist:keys=common_pid.execname,id.syscall:onmatch(raw_syscalls.sys_enter).synthetic_sys_enter($comm, id)' >> events/raw_syscalls/sys_enter/trigger
$ echo '!hist:keys=common_pid.execname,id.syscall:vals=hitcount:comm=common_pid.execname' >> events/raw_syscalls/sys_enter/trigger

[  100.263533] ==================================================================
[  100.264634] BUG: KASAN: slab-use-after-free in resolve_var_refs+0xc7/0x180
[  100.265520] Read of size 8 at addr ffff88810375d0f0 by task bash/439
[  100.266320]
[  100.266533] CPU: 2 PID: 439 Comm: bash Not tainted 6.5.0-rc1 #4
[  100.267277] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-20220807_005459-localhost 04/01/2014
[  100.268561] Call Trace:
[  100.268902]  <TASK>
[  100.269189]  dump_stack_lvl+0x4c/0x70
[  100.269680]  print_report+0xc5/0x600
[  100.270165]  ? resolve_var_refs+0xc7/0x180
[  100.270697]  ? kasan_complete_mode_report_info+0x80/0x1f0
[  100.271389]  ? resolve_var_refs+0xc7/0x180
[  100.271913]  kasan_report+0xbd/0x100
[  100.272380]  ? resolve_var_refs+0xc7/0x180
[  100.272920]  __asan_load8+0x71/0xa0
[  100.273377]  resolve_var_refs+0xc7/0x180
[  100.273888]  event_hist_trigger+0x749/0x860
[  100.274505]  ? kasan_save_stack+0x2a/0x50
[  100.275024]  ? kasan_set_track+0x29/0x40
[  100.275536]  ? __pfx_event_hist_trigger+0x10/0x10
[  100.276138]  ? ksys_write+0xd1/0x170
[  100.276607]  ? do_syscall_64+0x3c/0x90
[  100.277099]  ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  100.277771]  ? destroy_hist_data+0x446/0x470
[  100.278324]  ? event_hist_trigger_parse+0xa6c/0x3860
[  100.278962]  ? __pfx_event_hist_trigger_parse+0x10/0x10
[  100.279627]  ? __kasan_check_write+0x18/0x20
[  100.280177]  ? mutex_unlock+0x85/0xd0
[  100.280660]  ? __pfx_mutex_unlock+0x10/0x10
[  100.281200]  ? kfree+0x7b/0x120
[  100.281619]  ? ____kasan_slab_free+0x15d/0x1d0
[  100.282197]  ? event_trigger_write+0xac/0x100
[  100.282764]  ? __kasan_slab_free+0x16/0x20
[  100.283293]  ? __kmem_cache_free+0x153/0x2f0
[  100.283844]  ? sched_mm_cid_remote_clear+0xb1/0x250
[  100.284550]  ? __pfx_sched_mm_cid_remote_clear+0x10/0x10
[  100.285221]  ? event_trigger_write+0xbc/0x100
[  100.285781]  ? __kasan_check_read+0x15/0x20
[  100.286321]  ? __bitmap_weight+0x66/0xa0
[  100.286833]  ? _find_next_bit+0x46/0xe0
[  100.287334]  ? task_mm_cid_work+0x37f/0x450
[  100.287872]  event_triggers_call+0x84/0x150
[  100.288408]  trace_event_buffer_commit+0x339/0x430
[  100.289073]  ? ring_buffer_event_data+0x3f/0x60
[  100.292189]  trace_event_raw_event_sys_enter+0x8b/0xe0
[  100.295434]  syscall_trace_enter.constprop.0+0x18f/0x1b0
[  100.298653]  syscall_enter_from_user_mode+0x32/0x40
[  100.301808]  do_syscall_64+0x1a/0x90
[  100.304748]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  100.307775] RIP: 0033:0x7f686c75c1cb
[  100.310617] Code: 73 01 c3 48 8b 0d 65 3c 10 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 21 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 35 3c 10 00 f7 d8 64 89 01 48
[  100.317847] RSP: 002b:00007ffc60137a38 EFLAGS: 00000246 ORIG_RAX: 0000000000000021
[  100.321200] RAX: ffffffffffffffda RBX: 000055f566469ea0 RCX: 00007f686c75c1cb
[  100.324631] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 000000000000000a
[  100.328104] RBP: 00007ffc60137ac0 R08: 00007f686c818460 R09: 000000000000000a
[  100.331509] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
[  100.334992] R13: 0000000000000007 R14: 000000000000000a R15: 0000000000000007
[  100.338381]  </TASK>

We hit the bug because when second hist trigger has was created
has_hist_vars() returned false because hist trigger did not have
variables. As a result of that save_hist_vars() was not called to add
the trigger to trace_array->hist_vars. Later on when we attempted to
remove the first histogram find_any_var_ref() failed to detect it is
being used because it did not find the second trigger in hist_vars list.

With this change we wait until trigger actions are created so we can take
into consideration if hist trigger has variable references. Also, now we
check the return value of save_hist_vars() and fail trigger creation if
save_hist_vars() fails.

Link: https://lore.kernel.org/linux-trace-kernel/20230712223021.636335-1-mkhalfella@purestorage.com

Cc: stable@vger.kernel.org
Fixes: 067fe038e7 ("tracing: Add variable reference handling to hist triggers")
Signed-off-by: Mohamed Khalfella <mkhalfella@purestorage.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-12 19:08:56 -04:00
Steven Rostedt (Google)
bec3c25c24 tracing: Stop FORTIFY_SOURCE complaining about stack trace caller
The stack_trace event is an event created by the tracing subsystem to
store stack traces. It originally just contained a hard coded array of 8
words to hold the stack, and a "size" to know how many entries are there.
This is exported to user space as:

name: kernel_stack
ID: 4
format:
	field:unsigned short common_type;	offset:0;	size:2;	signed:0;
	field:unsigned char common_flags;	offset:2;	size:1;	signed:0;
	field:unsigned char common_preempt_count;	offset:3;	size:1;	signed:0;
	field:int common_pid;	offset:4;	size:4;	signed:1;

	field:int size;	offset:8;	size:4;	signed:1;
	field:unsigned long caller[8];	offset:16;	size:64;	signed:0;

print fmt: "\t=> %ps\n\t=> %ps\n\t=> %ps\n" "\t=> %ps\n\t=> %ps\n\t=> %ps\n" "\t=> %ps\n\t=> %ps\n",i
 (void *)REC->caller[0], (void *)REC->caller[1], (void *)REC->caller[2],
 (void *)REC->caller[3], (void *)REC->caller[4], (void *)REC->caller[5],
 (void *)REC->caller[6], (void *)REC->caller[7]

Where the user space tracers could parse the stack. The library was
updated for this specific event to only look at the size, and not the
array. But some older users still look at the array (note, the older code
still checks to make sure the array fits inside the event that it read.
That is, if only 4 words were saved, the parser would not read the fifth
word because it will see that it was outside of the event size).

This event was changed a while ago to be more dynamic, and would save a
full stack even if it was greater than 8 words. It does this by simply
allocating more ring buffer to hold the extra words. Then it copies in the
stack via:

	memcpy(&entry->caller, fstack->calls, size);

As the entry is struct stack_entry, that is created by a macro to both
create the structure and export this to user space, it still had the caller
field of entry defined as: unsigned long caller[8].

When the stack is greater than 8, the FORTIFY_SOURCE code notices that the
amount being copied is greater than the source array and complains about
it. It has no idea that the source is pointing to the ring buffer with the
required allocation.

To hide this from the FORTIFY_SOURCE logic, pointer arithmetic is used:

	ptr = ring_buffer_event_data(event);
	entry = ptr;
	ptr += offsetof(typeof(*entry), caller);
	memcpy(ptr, fstack->calls, size);

Link: https://lore.kernel.org/all/20230612160748.4082850-1-svens@linux.ibm.com/
Link: https://lore.kernel.org/linux-trace-kernel/20230712105235.5fc441aa@gandalf.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Tested-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-12 17:47:49 -04:00
Zheng Yejian
26efd79c46 ftrace: Fix possible warning on checking all pages used in ftrace_process_locs()
As comments in ftrace_process_locs(), there may be NULL pointers in
mcount_loc section:
 > Some architecture linkers will pad between
 > the different mcount_loc sections of different
 > object files to satisfy alignments.
 > Skip any NULL pointers.

After commit 20e5227e9f ("ftrace: allow NULL pointers in mcount_loc"),
NULL pointers will be accounted when allocating ftrace pages but skipped
before adding into ftrace pages, this may result in some pages not being
used. Then after commit 706c81f87f ("ftrace: Remove extra helper
functions"), warning may occur at:
  WARN_ON(pg->next);

To fix it, only warn for case that no pointers skipped but pages not used
up, then free those unused pages after releasing ftrace_lock.

Link: https://lore.kernel.org/linux-trace-kernel/20230712060452.3175675-1-zhengyejian1@huawei.com

Cc: stable@vger.kernel.org
Fixes: 706c81f87f ("ftrace: Remove extra helper functions")
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-12 17:47:37 -04:00
Linus Torvalds
9a3236ce48 Probes fixes and clean ups for v6.5-rc1:
- Fix fprobe's rethook release timing issue(1). Release rethook after
   ftrace_ops is unregistered so that the rethook is not accessed after
   free.
 
 - Fix fprobe's rethook access timing issue(2). Stop rethook before
   ftrace_ops is unregistered so that the rethook is NOT keep using
   after exiting the unregister_fprobe().
 
 - Fix eprobe cleanup logic. If it attaches to multiple events and failes
   to enable one of them, rollback all enabled events correctly.
 
 - Fix fprobe to unlock ftrace recursion lock correctly when it missed
   by another running kprobe.
 
 - Cleanup kprobe to remove unnecessary NULL.
 
 - Cleanup kprobe to remove unnecessary 0 initializations.
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Merge tag 'probes-fixes-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull probes fixes from Masami Hiramatsu:

 - Fix fprobe's rethook release issues:

     - Release rethook after ftrace_ops is unregistered so that the
       rethook is not accessed after free.

     - Stop rethook before ftrace_ops is unregistered so that the
       rethook is NOT used after exiting unregister_fprobe()

 - Fix eprobe cleanup logic. If it attaches to multiple events and
   failes to enable one of them, rollback all enabled events correctly.

 - Fix fprobe to unlock ftrace recursion lock correctly when it missed
   by another running kprobe.

 - Cleanup kprobe to remove unnecessary NULL.

 - Cleanup kprobe to remove unnecessary 0 initializations.

* tag 'probes-fixes-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  fprobe: Ensure running fprobe_exit_handler() finished before calling rethook_free()
  kernel: kprobes: Remove unnecessary ‘0’ values
  kprobes: Remove unnecessary ‘NULL’ values from correct_ret_addr
  fprobe: add unlock to match a succeeded ftrace_test_recursion_trylock
  kernel/trace: Fix cleanup logic of enable_trace_eprobe
  fprobe: Release rethook after the ftrace_ops is unregistered
2023-07-12 12:01:16 -07:00
Zheng Yejian
7e42907f3a ring-buffer: Fix deadloop issue on reading trace_pipe
Soft lockup occurs when reading file 'trace_pipe':

  watchdog: BUG: soft lockup - CPU#6 stuck for 22s! [cat:4488]
  [...]
  RIP: 0010:ring_buffer_empty_cpu+0xed/0x170
  RSP: 0018:ffff88810dd6fc48 EFLAGS: 00000246
  RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff93d1aaeb
  RDX: ffff88810a280040 RSI: 0000000000000008 RDI: ffff88811164b218
  RBP: ffff88811164b218 R08: 0000000000000000 R09: ffff88815156600f
  R10: ffffed102a2acc01 R11: 0000000000000001 R12: 0000000051651901
  R13: 0000000000000000 R14: ffff888115e49500 R15: 0000000000000000
  [...]
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f8d853c2000 CR3: 000000010dcd8000 CR4: 00000000000006e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   __find_next_entry+0x1a8/0x4b0
   ? peek_next_entry+0x250/0x250
   ? down_write+0xa5/0x120
   ? down_write_killable+0x130/0x130
   trace_find_next_entry_inc+0x3b/0x1d0
   tracing_read_pipe+0x423/0xae0
   ? tracing_splice_read_pipe+0xcb0/0xcb0
   vfs_read+0x16b/0x490
   ksys_read+0x105/0x210
   ? __ia32_sys_pwrite64+0x200/0x200
   ? switch_fpu_return+0x108/0x220
   do_syscall_64+0x33/0x40
   entry_SYSCALL_64_after_hwframe+0x61/0xc6

Through the vmcore, I found it's because in tracing_read_pipe(),
ring_buffer_empty_cpu() found some buffer is not empty but then it
cannot read anything due to "rb_num_of_entries() == 0" always true,
Then it infinitely loop the procedure due to user buffer not been
filled, see following code path:

  tracing_read_pipe() {
    ... ...
    waitagain:
      tracing_wait_pipe() // 1. find non-empty buffer here
      trace_find_next_entry_inc()  // 2. loop here try to find an entry
        __find_next_entry()
          ring_buffer_empty_cpu();  // 3. find non-empty buffer
          peek_next_entry()  // 4. but peek always return NULL
            ring_buffer_peek()
              rb_buffer_peek()
                rb_get_reader_page()
                  // 5. because rb_num_of_entries() == 0 always true here
                  //    then return NULL
      // 6. user buffer not been filled so goto 'waitgain'
      //    and eventually leads to an deadloop in kernel!!!
  }

By some analyzing, I found that when resetting ringbuffer, the 'entries'
of its pages are not all cleared (see rb_reset_cpu()). Then when reducing
the ringbuffer, and if some reduced pages exist dirty 'entries' data, they
will be added into 'cpu_buffer->overrun' (see rb_remove_pages()), which
cause wrong 'overrun' count and eventually cause the deadloop issue.

To fix it, we need to clear every pages in rb_reset_cpu().

Link: https://lore.kernel.org/linux-trace-kernel/20230708225144.3785600-1-zhengyejian1@huawei.com

Cc: stable@vger.kernel.org
Fixes: a5fb833172 ("ring-buffer: Fix uninitialized read_stamp")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-12 12:15:26 -04:00
Arnd Bergmann
7d8b31b73c tracing: arm64: Avoid missing-prototype warnings
These are all tracing W=1 warnings in arm64 allmodconfig about missing
prototypes:

kernel/trace/trace_kprobe_selftest.c:7:5: error: no previous prototype for 'kprobe_trace_selftest_target' [-Werror=missing-pro
totypes]
kernel/trace/ftrace.c:329:5: error: no previous prototype for '__register_ftrace_function' [-Werror=missing-prototypes]
kernel/trace/ftrace.c:372:5: error: no previous prototype for '__unregister_ftrace_function' [-Werror=missing-prototypes]
kernel/trace/ftrace.c:4130:15: error: no previous prototype for 'arch_ftrace_match_adjust' [-Werror=missing-prototypes]
kernel/trace/fgraph.c:243:15: error: no previous prototype for 'ftrace_return_to_handler' [-Werror=missing-prototypes]
kernel/trace/fgraph.c:358:6: error: no previous prototype for 'ftrace_graph_sleep_time_control' [-Werror=missing-prototypes]
arch/arm64/kernel/ftrace.c:460:6: error: no previous prototype for 'prepare_ftrace_return' [-Werror=missing-prototypes]
arch/arm64/kernel/ptrace.c:2172:5: error: no previous prototype for 'syscall_trace_enter' [-Werror=missing-prototypes]
arch/arm64/kernel/ptrace.c:2195:6: error: no previous prototype for 'syscall_trace_exit' [-Werror=missing-prototypes]

Move the declarations to an appropriate header where they can be seen
by the caller and callee, and make sure the headers are included where
needed.

Link: https://lore.kernel.org/linux-trace-kernel/20230517125215.930689-1-arnd@kernel.org

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Florent Revest <revest@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
[ Fixed ftrace_return_to_handler() to handle CONFIG_HAVE_FUNCTION_GRAPH_RETVAL case ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-12 12:06:04 -04:00
Beau Belgrave
d0a3022f30 tracing/user_events: Fix struct arg size match check
When users register an event the name of the event and it's argument are
checked to ensure they match if the event already exists. Normally all
arguments are in the form of "type name", except for when the type
starts with "struct ". In those cases, the size of the struct is passed
in addition to the name, IE: "struct my_struct a 20" for an argument
that is of type "struct my_struct" with a field name of "a" and has the
size of 20 bytes.

The current code does not honor the above case properly when comparing
a match. This causes the event register to fail even when the same
string was used for events that contain a struct argument within them.
The example above "struct my_struct a 20" generates a match string of
"struct my_struct a" omitting the size field.

Add the struct size of the existing field when generating a comparison
string for a struct field to ensure proper match checking.

Link: https://lkml.kernel.org/r/20230629235049.581-2-beaub@linux.microsoft.com

Cc: stable@vger.kernel.org
Fixes: e6f89a1498 ("tracing/user_events: Ensure user provided strings are safely formatted")
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-10 21:38:13 -04:00
Masami Hiramatsu (Google)
195b9cb5b2 fprobe: Ensure running fprobe_exit_handler() finished before calling rethook_free()
Ensure running fprobe_exit_handler() has finished before
calling rethook_free() in the unregister_fprobe() so that caller can free
the fprobe right after unregister_fprobe().

unregister_fprobe() ensured that all running fprobe_entry/exit_handler()
have finished by calling unregister_ftrace_function() which synchronizes
RCU. But commit 5f81018753 ("fprobe: Release rethook after the ftrace_ops
is unregistered") changed to call rethook_free() after
unregister_ftrace_function(). So call rethook_stop() to make rethook
disabled before unregister_ftrace_function() and ensure it again.

Here is the possible code flow that can call the exit handler after
unregister_fprobe().

------
 CPU1                              CPU2
 call unregister_fprobe(fp)
 ...
                                   __fprobe_handler()
                                   rethook_hook() on probed function
 unregister_ftrace_function()
                                   return from probed function
                                   rethook hooks
                                   find rh->handler == fprobe_exit_handler
                                   call fprobe_exit_handler()
 rethook_free():
   set rh->handler = NULL;
 return from unreigster_fprobe;
                                   call fp->exit_handler() <- (*)
------

(*) At this point, the exit handler is called after returning from
unregister_fprobe().

This fixes it as following;
------
 CPU1                              CPU2
 call unregister_fprobe()
 ...
 rethook_stop():
   set rh->handler = NULL;
                                   __fprobe_handler()
                                   rethook_hook() on probed function
 unregister_ftrace_function()
                                   return from probed function
                                   rethook hooks
                                   find rh->handler == NULL
                                   return from rethook
 rethook_free()
 return from unreigster_fprobe;
------

Link: https://lore.kernel.org/all/168873859949.156157.13039240432299335849.stgit@devnote2/

Fixes: 5f81018753 ("fprobe: Release rethook after the ftrace_ops is unregistered")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-11 09:17:01 +09:00
Ze Gao
5f0c584daf fprobe: add unlock to match a succeeded ftrace_test_recursion_trylock
Unlock ftrace recursion lock when fprobe_kprobe_handler() is failed
because of some running kprobe.

Link: https://lore.kernel.org/all/20230703092336.268371-1-zegao@tencent.com/

Fixes: 3cc4e2c5fb ("fprobe: make fprobe_kprobe_handler recursion free")
Reported-by: Yafang <laoar.shao@gmail.com>
Closes: https://lore.kernel.org/linux-trace-kernel/CALOAHbC6UpfFOOibdDiC7xFc5YFUgZnk3MZ=3Ny6we=AcrNbew@mail.gmail.com/
Signed-off-by: Ze Gao <zegao@tencent.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-11 00:48:33 +09:00
Tzvetomir Stoyanov (VMware)
cf0a624dc7 kernel/trace: Fix cleanup logic of enable_trace_eprobe
The enable_trace_eprobe() function enables all event probes, attached
to given trace probe. If an error occurs in enabling one of the event
probes, all others should be roll backed. There is a bug in that roll
back logic - instead of all event probes, only the failed one is
disabled.

Link: https://lore.kernel.org/all/20230703042853.1427493-1-tz.stoyanov@gmail.com/

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: 7491e2c442 ("tracing: Add a probe that attaches to trace events")
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-11 00:44:57 +09:00
Linus Torvalds
8066178f53 Tracing fixes for 6.5:
- Fix bad git merge of #endif in arm64 code
   A merge of the arm64 tree caused #endif to go into the wrong place
 
 - Fix crash on lseek of write access to tracefs/error_log
   Opening error_log as write only, and then doing an lseek() causes
   a kernel panic, because the lseek() handle expects a "seq_file"
   to exist (which is not done on write only opens). Use tracing_lseek()
   that tests for this instead of calling the default seq lseek handler.
 
 - Check for negative instead of -E2BIG for error on strscpy() returns
   Instead of testing for -E2BIG from strscpy(), to be more robust,
   check for less than zero, which will make sure it catches any error
   that strscpy() may someday return.
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Merge tag 'trace-v6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix bad git merge of #endif in arm64 code

   A merge of the arm64 tree caused #endif to go into the wrong place

 - Fix crash on lseek of write access to tracefs/error_log

   Opening error_log as write only, and then doing an lseek() causes a
   kernel panic, because the lseek() handle expects a "seq_file" to
   exist (which is not done on write only opens). Use tracing_lseek()
   that tests for this instead of calling the default seq lseek handler.

 - Check for negative instead of -E2BIG for error on strscpy() returns

   Instead of testing for -E2BIG from strscpy(), to be more robust,
   check for less than zero, which will make sure it catches any error
   that strscpy() may someday return.

* tag 'trace-v6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/boot: Test strscpy() against less than zero for error
  arm64: ftrace: fix build error with CONFIG_FUNCTION_GRAPH_TRACER=n
  tracing: Fix null pointer dereference in tracing_err_log_open()
2023-07-06 19:07:15 -07:00
Steven Rostedt (Google)
fddca7db4a tracing/boot: Test strscpy() against less than zero for error
Instead of checking for -E2BIG, it is better to just check for less than
zero of strscpy() for error. Testing for -E2BIG is not very robust, and
the calling code does not really care about the error code, just that
there was an error.

One of the updates to convert strlcpy() to strscpy() had a v2 version
that changed the test from testing against -E2BIG to less than zero, but I
took the v1 version that still tested for -E2BIG.

Link: https://lore.kernel.org/linux-trace-kernel/20230615180420.400769-1-azeemshaikh38@gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20230704100807.707d1605@rorschach.local.home

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Azeem Shaikh <azeemshaikh38@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-05 10:30:49 -04:00
Mateusz Stachyra
02b0095e2f tracing: Fix null pointer dereference in tracing_err_log_open()
Fix an issue in function 'tracing_err_log_open'.
The function doesn't call 'seq_open' if the file is opened only with
write permissions, which results in 'file->private_data' being left as null.
If we then use 'lseek' on that opened file, 'seq_lseek' dereferences
'file->private_data' in 'mutex_lock(&m->lock)', resulting in a kernel panic.
Writing to this node requires root privileges, therefore this bug
has very little security impact.

Tracefs node: /sys/kernel/tracing/error_log

Example Kernel panic:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000038
Call trace:
 mutex_lock+0x30/0x110
 seq_lseek+0x34/0xb8
 __arm64_sys_lseek+0x6c/0xb8
 invoke_syscall+0x58/0x13c
 el0_svc_common+0xc4/0x10c
 do_el0_svc+0x24/0x98
 el0_svc+0x24/0x88
 el0t_64_sync_handler+0x84/0xe4
 el0t_64_sync+0x1b4/0x1b8
Code: d503201f aa0803e0 aa1f03e1 aa0103e9 (c8e97d02)
---[ end trace 561d1b49c12cf8a5 ]---
Kernel panic - not syncing: Oops: Fatal exception

Link: https://lore.kernel.org/linux-trace-kernel/20230703155237eucms1p4dfb6a19caa14c79eb6c823d127b39024@eucms1p4
Link: https://lore.kernel.org/linux-trace-kernel/20230704102706eucms1p30d7ecdcc287f46ad67679fc8491b2e0f@eucms1p3

Cc: stable@vger.kernel.org
Fixes: 8a062902be ("tracing: Add tracing error log")
Signed-off-by: Mateusz Stachyra <m.stachyra@samsung.com>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-05 09:45:45 -04:00
Linus Torvalds
d2a6fd45c5 Probes updates for v6.5:
- fprobe: Pass return address to the fprobe entry/exit callbacks so that
   the callbacks don't need to analyze pt_regs/stack to find the function
   return address.
 
 - kprobe events: cleanup usage of TPARG_FL_FENTRY and TPARG_FL_RETURN
   flags so that those are not set at once.
 
 - fprobe events:
  . Add a new fprobe events for tracing arbitrary function entry and
    exit as a trace event.
  . Add a new tracepoint events for tracing raw tracepoint as a trace
    event. This allows user to trace non user-exposed tracepoints.
  . Move eprobe's event parser code into probe event common file.
  . Introduce BTF (BPF type format) support to kernel probe (kprobe,
    fprobe and tracepoint probe) events so that user can specify traced
    function arguments by name. This also applies the type of argument
    when fetching the argument.
  . Introduce '$arg*' wildcard support if BTF is available. This expands
    the '$arg*' meta argument to all function argument automatically.
  . Check the return value types by BTF. If the function returns 'void',
    '$retval' is rejected.
  . Add some selftest script for fprobe events, tracepoint events and
    BTF support.
  . Update documentation about the fprobe events.
  . Some fixes for above features, document and selftests.
 
 - selftests for ftrace (except for new fprobe events):
  . Add a test case for multiple consecutive probes in a function which
    checks if ftrace based kprobe, optimized kprobe and normal kprobe
    can be defined in the same target function.
  . Add a test case for optimized probe, which checks whether kprobe
    can be optimized or not.
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Merge tag 'probes-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull probes updates from Masami Hiramatsu:

 - fprobe: Pass return address to the fprobe entry/exit callbacks so
   that the callbacks don't need to analyze pt_regs/stack to find the
   function return address.

 - kprobe events: cleanup usage of TPARG_FL_FENTRY and TPARG_FL_RETURN
   flags so that those are not set at once.

 - fprobe events:
      - Add a new fprobe events for tracing arbitrary function entry and
        exit as a trace event.
      - Add a new tracepoint events for tracing raw tracepoint as a
        trace event. This allows user to trace non user-exposed
        tracepoints.
      - Move eprobe's event parser code into probe event common file.
      - Introduce BTF (BPF type format) support to kernel probe (kprobe,
        fprobe and tracepoint probe) events so that user can specify
        traced function arguments by name. This also applies the type of
        argument when fetching the argument.
      - Introduce '$arg*' wildcard support if BTF is available. This
        expands the '$arg*' meta argument to all function argument
        automatically.
      - Check the return value types by BTF. If the function returns
        'void', '$retval' is rejected.
      - Add some selftest script for fprobe events, tracepoint events
        and BTF support.
      - Update documentation about the fprobe events.
      - Some fixes for above features, document and selftests.

 - selftests for ftrace (in addition to the new fprobe events):
      - Add a test case for multiple consecutive probes in a function
        which checks if ftrace based kprobe, optimized kprobe and normal
        kprobe can be defined in the same target function.
      - Add a test case for optimized probe, which checks whether kprobe
        can be optimized or not.

* tag 'probes-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/probes: Fix tracepoint event with $arg* to fetch correct argument
  Documentation: Fix typo of reference file name
  tracing/probes: Fix to return NULL and keep using current argc
  selftests/ftrace: Add new test case which checks for optimized probes
  selftests/ftrace: Add new test case which adds multiple consecutive probes in a function
  Documentation: tracing/probes: Add fprobe event tracing document
  selftests/ftrace: Add BTF arguments test cases
  selftests/ftrace: Add tracepoint probe test case
  tracing/probes: Add BTF retval type support
  tracing/probes: Add $arg* meta argument for all function args
  tracing/probes: Support function parameters if BTF is available
  tracing/probes: Move event parameter fetching code to common parser
  tracing/probes: Add tracepoint support on fprobe_events
  selftests/ftrace: Add fprobe related testcases
  tracing/probes: Add fprobe events for tracing function entry and exit.
  tracing/probes: Avoid setting TPARG_FL_FENTRY and TPARG_FL_RETURN
  fprobe: Pass return address to the handlers
2023-06-30 10:44:53 -07:00
Linus Torvalds
cccf0c2ee5 Tracing updates for 6.5:
- Add new feature to have function graph tracer record the return value.
   Adds a new option: funcgraph-retval ; when set, will show the return
   value of a function in the function graph tracer.
 
 - Also add the option: funcgraph-retval-hex where if it is not set, and
   the return value is an error code, then it will return the decimal of
   the error code, otherwise it still reports the hex value.
 
 - Add the file /sys/kernel/tracing/osnoise/per_cpu/cpu<cpu>/timerlat_fd
   That when a application opens it, it becomes the task that the timer lat
   tracer traces. The application can also read this file to find out how
   it's being interrupted.
 
 - Add the file /sys/kernel/tracing/available_filter_functions_addrs
   that works just the same as available_filter_functions but also shows
   the addresses of the functions like kallsyms, except that it gives the
   address of where the fentry/mcount jump/nop is. This is used by BPF to
   make it easier to attach BPF programs to ftrace hooks.
 
 - Replace strlcpy with strscpy in the tracing boot code.
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Merge tag 'trace-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Add new feature to have function graph tracer record the return
   value. Adds a new option: funcgraph-retval ; when set, will show the
   return value of a function in the function graph tracer.

 - Also add the option: funcgraph-retval-hex where if it is not set, and
   the return value is an error code, then it will return the decimal of
   the error code, otherwise it still reports the hex value.

 - Add the file /sys/kernel/tracing/osnoise/per_cpu/cpu<cpu>/timerlat_fd
   That when a application opens it, it becomes the task that the timer
   lat tracer traces. The application can also read this file to find
   out how it's being interrupted.

 - Add the file /sys/kernel/tracing/available_filter_functions_addrs
   that works just the same as available_filter_functions but also shows
   the addresses of the functions like kallsyms, except that it gives
   the address of where the fentry/mcount jump/nop is. This is used by
   BPF to make it easier to attach BPF programs to ftrace hooks.

 - Replace strlcpy with strscpy in the tracing boot code.

* tag 'trace-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Fix warnings when building htmldocs for function graph retval
  riscv: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
  tracing/boot: Replace strlcpy with strscpy
  tracing/timerlat: Add user-space interface
  tracing/osnoise: Skip running osnoise if all instances are off
  tracing/osnoise: Switch from PF_NO_SETAFFINITY to migrate_disable
  ftrace: Show all functions with addresses in available_filter_functions_addrs
  selftests/ftrace: Add funcgraph-retval test case
  LoongArch: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
  x86/ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
  arm64: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
  tracing: Add documentation for funcgraph-retval and funcgraph-retval-hex
  function_graph: Support recording and printing the return value of function
  fgraph: Add declaration of "struct fgraph_ret_regs"
2023-06-30 10:33:17 -07:00
Linus Torvalds
3ad7b12c72 tracing: Fix user event write on buffer disabled
The user events write currently returns the size of what was suppose to be
 written when tracing is disabled and nothing was written. Instead, behave like
 trace_marker and return -EBADF, as that is what is returned if a file is opened
 for read only, and a write is performed on it. Writing to the buffer
 that is disabled is like trying to write to a file opened for read
 only, as the buffer still can be read, but just not written to.
 
 This also includes test cases for this use case
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Merge tag 'trace-v6.4-rc7-v3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fix from Steven Rostedt:
 "Fix user event write on buffer disabled.

  The user events write currently returns the size of what was supposed
  to be written when tracing is disabled and nothing was written.

  Instead, behave like trace_marker and return -EBADF, as that is what
  is returned if a file is opened for read only, and a write is
  performed on it. Writing to the buffer that is disabled is like trying
  to write to a file opened for read only, as the buffer still can be
  read, but just not written to.

  This also includes test cases for this use case"

* tag 'trace-v6.4-rc7-v3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  selftests/user_events: Add test cases when event is disabled
  selftests/user_events: Enable the event before write_fault test in ftrace self-test
  tracing/user_events: Fix incorrect return value for writing operation when events are disabled
2023-06-29 17:36:00 -07:00
Linus Torvalds
3a8a670eee Networking changes for 6.5.
Core
 ----
 
  - Rework the sendpage & splice implementations. Instead of feeding
    data into sockets page by page extend sendmsg handlers to support
    taking a reference on the data, controlled by a new flag called
    MSG_SPLICE_PAGES. Rework the handling of unexpected-end-of-file
    to invoke an additional callback instead of trying to predict what
    the right combination of MORE/NOTLAST flags is.
    Remove the MSG_SENDPAGE_NOTLAST flag completely.
 
  - Implement SCM_PIDFD, a new type of CMSG type analogous to
    SCM_CREDENTIALS, but it contains pidfd instead of plain pid.
 
  - Enable socket busy polling with CONFIG_RT.
 
  - Improve reliability and efficiency of reporting for ref_tracker.
 
  - Auto-generate a user space C library for various Netlink families.
 
 Protocols
 ---------
 
  - Allow TCP to shrink the advertised window when necessary, prevent
    sk_rcvbuf auto-tuning from growing the window all the way up to
    tcp_rmem[2].
 
  - Use per-VMA locking for "page-flipping" TCP receive zerocopy.
 
  - Prepare TCP for device-to-device data transfers, by making sure
    that payloads are always attached to skbs as page frags.
 
  - Make the backoff time for the first N TCP SYN retransmissions
    linear. Exponential backoff is unnecessarily conservative.
 
  - Create a new MPTCP getsockopt to retrieve all info (MPTCP_FULL_INFO).
 
  - Avoid waking up applications using TLS sockets until we have
    a full record.
 
  - Allow using kernel memory for protocol ioctl callbacks, paving
    the way to issuing ioctls over io_uring.
 
  - Add nolocalbypass option to VxLAN, forcing packets to be fully
    encapsulated even if they are destined for a local IP address.
 
  - Make TCPv4 use consistent hash in TIME_WAIT and SYN_RECV. Ensure
    in-kernel ECMP implementation (e.g. Open vSwitch) select the same
    link for all packets. Support L4 symmetric hashing in Open vSwitch.
 
  - PPPoE: make number of hash bits configurable.
 
  - Allow DNS to be overwritten by DHCPACK in the in-kernel DHCP client
    (ipconfig).
 
  - Add layer 2 miss indication and filtering, allowing higher layers
    (e.g. ACL filters) to make forwarding decisions based on whether
    packet matched forwarding state in lower devices (bridge).
 
  - Support matching on Connectivity Fault Management (CFM) packets.
 
  - Hide the "link becomes ready" IPv6 messages by demoting their
    printk level to debug.
 
  - HSR: don't enable promiscuous mode if device offloads the proto.
 
  - Support active scanning in IEEE 802.15.4.
 
  - Continue work on Multi-Link Operation for WiFi 7.
 
 BPF
 ---
 
  - Add precision propagation for subprogs and callbacks. This allows
    maintaining verification efficiency when subprograms are used,
    or in fact passing the verifier at all for complex programs,
    especially those using open-coded iterators.
 
  - Improve BPF's {g,s}setsockopt() length handling. Previously BPF
    assumed the length is always equal to the amount of written data.
    But some protos allow passing a NULL buffer to discover what
    the output buffer *should* be, without writing anything.
 
  - Accept dynptr memory as memory arguments passed to helpers.
 
  - Add routing table ID to bpf_fib_lookup BPF helper.
 
  - Support O_PATH FDs in BPF_OBJ_PIN and BPF_OBJ_GET commands.
 
  - Drop bpf_capable() check in BPF_MAP_FREEZE command (used to mark
    maps as read-only).
 
  - Show target_{obj,btf}_id in tracing link fdinfo.
 
  - Addition of several new kfuncs (most of the names are self-explanatory):
    - Add a set of new dynptr kfuncs: bpf_dynptr_adjust(),
      bpf_dynptr_is_null(), bpf_dynptr_is_rdonly(), bpf_dynptr_size()
      and bpf_dynptr_clone().
    - bpf_task_under_cgroup()
    - bpf_sock_destroy() - force closing sockets
    - bpf_cpumask_first_and(), rework bpf_cpumask_any*() kfuncs
 
 Netfilter
 ---------
 
  - Relax set/map validation checks in nf_tables. Allow checking
    presence of an entry in a map without using the value.
 
  - Increase ip_vs_conn_tab_bits range for 64BIT builds.
 
  - Allow updating size of a set.
 
  - Improve NAT tuple selection when connection is closing.
 
 Driver API
 ----------
 
  - Integrate netdev with LED subsystem, to allow configuring HW
    "offloaded" blinking of LEDs based on link state and activity
    (i.e. packets coming in and out).
 
  - Support configuring rate selection pins of SFP modules.
 
  - Factor Clause 73 auto-negotiation code out of the drivers, provide
    common helper routines.
 
  - Add more fool-proof helpers for managing lifetime of MDIO devices
    associated with the PCS layer.
 
  - Allow drivers to report advanced statistics related to Time Aware
    scheduler offload (taprio).
 
  - Allow opting out of VF statistics in link dump, to allow more VFs
    to fit into the message.
 
  - Split devlink instance and devlink port operations.
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - Synopsys EMAC4 IP support (stmmac)
    - Marvell 88E6361 8 port (5x1GE + 3x2.5GE) switches
    - Marvell 88E6250 7 port switches
    - Microchip LAN8650/1 Rev.B0 PHYs
    - MediaTek MT7981/MT7988 built-in 1GE PHY driver
 
  - WiFi:
    - Realtek RTL8192FU, 2.4 GHz, b/g/n mode, 2T2R, 300 Mbps
    - Realtek RTL8723DS (SDIO variant)
    - Realtek RTL8851BE
 
  - CAN:
    - Fintek F81604
 
 Drivers
 -------
 
  - Ethernet NICs:
    - Intel (100G, ice):
      - support dynamic interrupt allocation
      - use meta data match instead of VF MAC addr on slow-path
    - nVidia/Mellanox:
      - extend link aggregation to handle 4, rather than just 2 ports
      - spawn sub-functions without any features by default
    - OcteonTX2:
      - support HTB (Tx scheduling/QoS) offload
      - make RSS hash generation configurable
      - support selecting Rx queue using TC filters
    - Wangxun (ngbe/txgbe):
      - add basic Tx/Rx packet offloads
      - add phylink support (SFP/PCS control)
    - Freescale/NXP (enetc):
      - report TAPRIO packet statistics
    - Solarflare/AMD:
      - support matching on IP ToS and UDP source port of outer header
      - VxLAN and GENEVE tunnel encapsulation over IPv4 or IPv6
      - add devlink dev info support for EF10
 
  - Virtual NICs:
    - Microsoft vNIC:
      - size the Rx indirection table based on requested configuration
      - support VLAN tagging
    - Amazon vNIC:
      - try to reuse Rx buffers if not fully consumed, useful for ARM
        servers running with 16kB pages
    - Google vNIC:
      - support TCP segmentation of >64kB frames
 
  - Ethernet embedded switches:
    - Marvell (mv88e6xxx):
      - enable USXGMII (88E6191X)
    - Microchip:
     - lan966x: add support for Egress Stage 0 ACL engine
     - lan966x: support mapping packet priority to internal switch
       priority (based on PCP or DSCP)
 
  - Ethernet PHYs:
    - Broadcom PHYs:
      - support for Wake-on-LAN for BCM54210E/B50212E
      - report LPI counter
    - Microsemi PHYs: support RGMII delay configuration (VSC85xx)
    - Micrel PHYs: receive timestamp in the frame (LAN8841)
    - Realtek PHYs: support optional external PHY clock
    - Altera TSE PCS: merge the driver into Lynx PCS which it is
      a variant of
 
  - CAN: Kvaser PCIEcan:
    - support packet timestamping
 
  - WiFi:
    - Intel (iwlwifi):
      - major update for new firmware and Multi-Link Operation (MLO)
      - configuration rework to drop test devices and split
        the different families
      - support for segmented PNVM images and power tables
      - new vendor entries for PPAG (platform antenna gain) feature
    - Qualcomm 802.11ax (ath11k):
      - Multiple Basic Service Set Identifier (MBSSID) and
        Enhanced MBSSID Advertisement (EMA) support in AP mode
      - support factory test mode
    - RealTek (rtw89):
      - add RSSI based antenna diversity
      - support U-NII-4 channels on 5 GHz band
    - RealTek (rtl8xxxu):
      - AP mode support for 8188f
      - support USB RX aggregation for the newer chips
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking changes from Jakub Kicinski:
 "WiFi 7 and sendpage changes are the biggest pieces of work for this
  release. The latter will definitely require fixes but I think that we
  got it to a reasonable point.

  Core:

   - Rework the sendpage & splice implementations

     Instead of feeding data into sockets page by page extend sendmsg
     handlers to support taking a reference on the data, controlled by a
     new flag called MSG_SPLICE_PAGES

     Rework the handling of unexpected-end-of-file to invoke an
     additional callback instead of trying to predict what the right
     combination of MORE/NOTLAST flags is

     Remove the MSG_SENDPAGE_NOTLAST flag completely

   - Implement SCM_PIDFD, a new type of CMSG type analogous to
     SCM_CREDENTIALS, but it contains pidfd instead of plain pid

   - Enable socket busy polling with CONFIG_RT

   - Improve reliability and efficiency of reporting for ref_tracker

   - Auto-generate a user space C library for various Netlink families

  Protocols:

   - Allow TCP to shrink the advertised window when necessary, prevent
     sk_rcvbuf auto-tuning from growing the window all the way up to
     tcp_rmem[2]

   - Use per-VMA locking for "page-flipping" TCP receive zerocopy

   - Prepare TCP for device-to-device data transfers, by making sure
     that payloads are always attached to skbs as page frags

   - Make the backoff time for the first N TCP SYN retransmissions
     linear. Exponential backoff is unnecessarily conservative

   - Create a new MPTCP getsockopt to retrieve all info
     (MPTCP_FULL_INFO)

   - Avoid waking up applications using TLS sockets until we have a full
     record

   - Allow using kernel memory for protocol ioctl callbacks, paving the
     way to issuing ioctls over io_uring

   - Add nolocalbypass option to VxLAN, forcing packets to be fully
     encapsulated even if they are destined for a local IP address

   - Make TCPv4 use consistent hash in TIME_WAIT and SYN_RECV. Ensure
     in-kernel ECMP implementation (e.g. Open vSwitch) select the same
     link for all packets. Support L4 symmetric hashing in Open vSwitch

   - PPPoE: make number of hash bits configurable

   - Allow DNS to be overwritten by DHCPACK in the in-kernel DHCP client
     (ipconfig)

   - Add layer 2 miss indication and filtering, allowing higher layers
     (e.g. ACL filters) to make forwarding decisions based on whether
     packet matched forwarding state in lower devices (bridge)

   - Support matching on Connectivity Fault Management (CFM) packets

   - Hide the "link becomes ready" IPv6 messages by demoting their
     printk level to debug

   - HSR: don't enable promiscuous mode if device offloads the proto

   - Support active scanning in IEEE 802.15.4

   - Continue work on Multi-Link Operation for WiFi 7

  BPF:

   - Add precision propagation for subprogs and callbacks. This allows
     maintaining verification efficiency when subprograms are used, or
     in fact passing the verifier at all for complex programs,
     especially those using open-coded iterators

   - Improve BPF's {g,s}setsockopt() length handling. Previously BPF
     assumed the length is always equal to the amount of written data.
     But some protos allow passing a NULL buffer to discover what the
     output buffer *should* be, without writing anything

   - Accept dynptr memory as memory arguments passed to helpers

   - Add routing table ID to bpf_fib_lookup BPF helper

   - Support O_PATH FDs in BPF_OBJ_PIN and BPF_OBJ_GET commands

   - Drop bpf_capable() check in BPF_MAP_FREEZE command (used to mark
     maps as read-only)

   - Show target_{obj,btf}_id in tracing link fdinfo

   - Addition of several new kfuncs (most of the names are
     self-explanatory):
      - Add a set of new dynptr kfuncs: bpf_dynptr_adjust(),
        bpf_dynptr_is_null(), bpf_dynptr_is_rdonly(), bpf_dynptr_size()
        and bpf_dynptr_clone().
      - bpf_task_under_cgroup()
      - bpf_sock_destroy() - force closing sockets
      - bpf_cpumask_first_and(), rework bpf_cpumask_any*() kfuncs

  Netfilter:

   - Relax set/map validation checks in nf_tables. Allow checking
     presence of an entry in a map without using the value

   - Increase ip_vs_conn_tab_bits range for 64BIT builds

   - Allow updating size of a set

   - Improve NAT tuple selection when connection is closing

  Driver API:

   - Integrate netdev with LED subsystem, to allow configuring HW
     "offloaded" blinking of LEDs based on link state and activity
     (i.e. packets coming in and out)

   - Support configuring rate selection pins of SFP modules

   - Factor Clause 73 auto-negotiation code out of the drivers, provide
     common helper routines

   - Add more fool-proof helpers for managing lifetime of MDIO devices
     associated with the PCS layer

   - Allow drivers to report advanced statistics related to Time Aware
     scheduler offload (taprio)

   - Allow opting out of VF statistics in link dump, to allow more VFs
     to fit into the message

   - Split devlink instance and devlink port operations

  New hardware / drivers:

   - Ethernet:
      - Synopsys EMAC4 IP support (stmmac)
      - Marvell 88E6361 8 port (5x1GE + 3x2.5GE) switches
      - Marvell 88E6250 7 port switches
      - Microchip LAN8650/1 Rev.B0 PHYs
      - MediaTek MT7981/MT7988 built-in 1GE PHY driver

   - WiFi:
      - Realtek RTL8192FU, 2.4 GHz, b/g/n mode, 2T2R, 300 Mbps
      - Realtek RTL8723DS (SDIO variant)
      - Realtek RTL8851BE

   - CAN:
      - Fintek F81604

  Drivers:

   - Ethernet NICs:
      - Intel (100G, ice):
         - support dynamic interrupt allocation
         - use meta data match instead of VF MAC addr on slow-path
      - nVidia/Mellanox:
         - extend link aggregation to handle 4, rather than just 2 ports
         - spawn sub-functions without any features by default
      - OcteonTX2:
         - support HTB (Tx scheduling/QoS) offload
         - make RSS hash generation configurable
         - support selecting Rx queue using TC filters
      - Wangxun (ngbe/txgbe):
         - add basic Tx/Rx packet offloads
         - add phylink support (SFP/PCS control)
      - Freescale/NXP (enetc):
         - report TAPRIO packet statistics
      - Solarflare/AMD:
         - support matching on IP ToS and UDP source port of outer
           header
         - VxLAN and GENEVE tunnel encapsulation over IPv4 or IPv6
         - add devlink dev info support for EF10

   - Virtual NICs:
      - Microsoft vNIC:
         - size the Rx indirection table based on requested
           configuration
         - support VLAN tagging
      - Amazon vNIC:
         - try to reuse Rx buffers if not fully consumed, useful for ARM
           servers running with 16kB pages
      - Google vNIC:
         - support TCP segmentation of >64kB frames

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - enable USXGMII (88E6191X)
      - Microchip:
         - lan966x: add support for Egress Stage 0 ACL engine
         - lan966x: support mapping packet priority to internal switch
           priority (based on PCP or DSCP)

   - Ethernet PHYs:
      - Broadcom PHYs:
         - support for Wake-on-LAN for BCM54210E/B50212E
         - report LPI counter
      - Microsemi PHYs: support RGMII delay configuration (VSC85xx)
      - Micrel PHYs: receive timestamp in the frame (LAN8841)
      - Realtek PHYs: support optional external PHY clock
      - Altera TSE PCS: merge the driver into Lynx PCS which it is a
        variant of

   - CAN: Kvaser PCIEcan:
      - support packet timestamping

   - WiFi:
      - Intel (iwlwifi):
         - major update for new firmware and Multi-Link Operation (MLO)
         - configuration rework to drop test devices and split the
           different families
         - support for segmented PNVM images and power tables
         - new vendor entries for PPAG (platform antenna gain) feature
      - Qualcomm 802.11ax (ath11k):
         - Multiple Basic Service Set Identifier (MBSSID) and Enhanced
           MBSSID Advertisement (EMA) support in AP mode
         - support factory test mode
      - RealTek (rtw89):
         - add RSSI based antenna diversity
         - support U-NII-4 channels on 5 GHz band
      - RealTek (rtl8xxxu):
         - AP mode support for 8188f
         - support USB RX aggregation for the newer chips"

* tag 'net-next-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1602 commits)
  net: scm: introduce and use scm_recv_unix helper
  af_unix: Skip SCM_PIDFD if scm->pid is NULL.
  net: lan743x: Simplify comparison
  netlink: Add __sock_i_ino() for __netlink_diag_dump().
  net: dsa: avoid suspicious RCU usage for synced VLAN-aware MAC addresses
  Revert "af_unix: Call scm_recv() only after scm_set_cred()."
  phylink: ReST-ify the phylink_pcs_neg_mode() kdoc
  libceph: Partially revert changes to support MSG_SPLICE_PAGES
  net: phy: mscc: fix packet loss due to RGMII delays
  net: mana: use vmalloc_array and vcalloc
  net: enetc: use vmalloc_array and vcalloc
  ionic: use vmalloc_array and vcalloc
  pds_core: use vmalloc_array and vcalloc
  gve: use vmalloc_array and vcalloc
  octeon_ep: use vmalloc_array and vcalloc
  net: usb: qmi_wwan: add u-blox 0x1312 composition
  perf trace: fix MSG_SPLICE_PAGES build error
  ipvlan: Fix return value of ipvlan_queue_xmit()
  netfilter: nf_tables: fix underflow in chain reference counter
  netfilter: nf_tables: unbind non-anonymous set if rule construction fails
  ...
2023-06-28 16:43:10 -07:00
Linus Torvalds
6e17c6de3d - Yosry Ahmed brought back some cgroup v1 stats in OOM logs.
- Yosry has also eliminated cgroup's atomic rstat flushing.
 
 - Nhat Pham adds the new cachestat() syscall.  It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability.
 
 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning.
 
 - Lorenzo Stoakes has done some maintanance work on the get_user_pages()
   interface.
 
 - Liam Howlett continues with cleanups and maintenance work to the maple
   tree code.  Peng Zhang also does some work on maple tree.
 
 - Johannes Weiner has done some cleanup work on the compaction code.
 
 - David Hildenbrand has contributed additional selftests for
   get_user_pages().
 
 - Thomas Gleixner has contributed some maintenance and optimization work
   for the vmalloc code.
 
 - Baolin Wang has provided some compaction cleanups,
 
 - SeongJae Park continues maintenance work on the DAMON code.
 
 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting.
 
 - Christoph Hellwig has some cleanups for the filemap/directio code.
 
 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the provided
   APIs rather than open-coding accesses.
 
 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings.
 
 - John Hubbard has a series of fixes to the MM selftesting code.
 
 - ZhangPeng continues the folio conversion campaign.
 
 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock.
 
 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment from
   128 to 8.
 
 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management.
 
 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code.
 
 - Vishal Moola also has done some folio conversion work.
 
 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch.
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Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull mm updates from Andrew Morton:

 - Yosry Ahmed brought back some cgroup v1 stats in OOM logs

 - Yosry has also eliminated cgroup's atomic rstat flushing

 - Nhat Pham adds the new cachestat() syscall. It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability

 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning

 - Lorenzo Stoakes has done some maintanance work on the
   get_user_pages() interface

 - Liam Howlett continues with cleanups and maintenance work to the
   maple tree code. Peng Zhang also does some work on maple tree

 - Johannes Weiner has done some cleanup work on the compaction code

 - David Hildenbrand has contributed additional selftests for
   get_user_pages()

 - Thomas Gleixner has contributed some maintenance and optimization
   work for the vmalloc code

 - Baolin Wang has provided some compaction cleanups,

 - SeongJae Park continues maintenance work on the DAMON code

 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting

 - Christoph Hellwig has some cleanups for the filemap/directio code

 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the
   provided APIs rather than open-coding accesses

 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings

 - John Hubbard has a series of fixes to the MM selftesting code

 - ZhangPeng continues the folio conversion campaign

 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock

 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment
   from 128 to 8

 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management

 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code

 - Vishal Moola also has done some folio conversion work

 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch

* tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits)
  mm/hugetlb: remove hugetlb_set_page_subpool()
  mm: nommu: correct the range of mmap_sem_read_lock in task_mem()
  hugetlb: revert use of page_cache_next_miss()
  Revert "page cache: fix page_cache_next/prev_miss off by one"
  mm/vmscan: fix root proactive reclaim unthrottling unbalanced node
  mm: memcg: rename and document global_reclaim()
  mm: kill [add|del]_page_to_lru_list()
  mm: compaction: convert to use a folio in isolate_migratepages_block()
  mm: zswap: fix double invalidate with exclusive loads
  mm: remove unnecessary pagevec includes
  mm: remove references to pagevec
  mm: rename invalidate_mapping_pagevec to mapping_try_invalidate
  mm: remove struct pagevec
  net: convert sunrpc from pagevec to folio_batch
  i915: convert i915_gpu_error to use a folio_batch
  pagevec: rename fbatch_count()
  mm: remove check_move_unevictable_pages()
  drm: convert drm_gem_put_pages() to use a folio_batch
  i915: convert shmem_sg_free_table() to use a folio_batch
  scatterlist: add sg_set_folio()
  ...
2023-06-28 10:28:11 -07:00
sunliming
f6d026eea3 tracing/user_events: Fix incorrect return value for writing operation when events are disabled
The writing operation return the count of writes regardless of whether events
are enabled or disabled. Switch it to return -EBADF to indicates that the event
is disabled.

Link: https://lkml.kernel.org/r/20230626111344.19136-2-sunliming@kylinos.cn

Cc: stable@vger.kernel.org
7f5a08c79d ("user_events: Add minimal support for trace_event into ftrace")
Acked-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: sunliming <sunliming@kylinos.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-28 11:00:50 -04:00
Linus Torvalds
582c161cf3 hardening updates for v6.5-rc1
- Fix KMSAN vs FORTIFY in strlcpy/strlcat (Alexander Potapenko)
 
 - Convert strreplace() to return string start (Andy Shevchenko)
 
 - Flexible array conversions (Arnd Bergmann, Wyes Karny, Kees Cook)
 
 - Add missing function prototypes seen with W=1 (Arnd Bergmann)
 
 - Fix strscpy() kerndoc typo (Arne Welzel)
 
 - Replace strlcpy() with strscpy() across many subsystems which were
   either Acked by respective maintainers or were trivial changes that
   went ignored for multiple weeks (Azeem Shaikh)
 
 - Remove unneeded cc-option test for UBSAN_TRAP (Nick Desaulniers)
 
 - Add KUnit tests for strcat()-family
 
 - Enable KUnit tests of FORTIFY wrappers under UML
 
 - Add more complete FORTIFY protections for strlcat()
 
 - Add missed disabling of FORTIFY for all arch purgatories.
 
 - Enable -fstrict-flex-arrays=3 globally
 
 - Tightening UBSAN_BOUNDS when using GCC
 
 - Improve checkpatch to check for strcpy, strncpy, and fake flex arrays
 
 - Improve use of const variables in FORTIFY
 
 - Add requested struct_size_t() helper for types not pointers
 
 - Add __counted_by macro for annotating flexible array size members
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Merge tag 'hardening-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardening updates from Kees Cook:
 "There are three areas of note:

  A bunch of strlcpy()->strscpy() conversions ended up living in my tree
  since they were either Acked by maintainers for me to carry, or got
  ignored for multiple weeks (and were trivial changes).

  The compiler option '-fstrict-flex-arrays=3' has been enabled
  globally, and has been in -next for the entire devel cycle. This
  changes compiler diagnostics (though mainly just -Warray-bounds which
  is disabled) and potential UBSAN_BOUNDS and FORTIFY _warning_
  coverage. In other words, there are no new restrictions, just
  potentially new warnings. Any new FORTIFY warnings we've seen have
  been fixed (usually in their respective subsystem trees). For more
  details, see commit df8fc4e934.

  The under-development compiler attribute __counted_by has been added
  so that we can start annotating flexible array members with their
  associated structure member that tracks the count of flexible array
  elements at run-time. It is possible (likely?) that the exact syntax
  of the attribute will change before it is finalized, but GCC and Clang
  are working together to sort it out. Any changes can be made to the
  macro while we continue to add annotations.

  As an example of that last case, I have a treewide commit waiting with
  such annotations found via Coccinelle:

    https://git.kernel.org/linus/adc5b3cb48a049563dc673f348eab7b6beba8a9b

  Also see commit dd06e72e68 for more details.

  Summary:

   - Fix KMSAN vs FORTIFY in strlcpy/strlcat (Alexander Potapenko)

   - Convert strreplace() to return string start (Andy Shevchenko)

   - Flexible array conversions (Arnd Bergmann, Wyes Karny, Kees Cook)

   - Add missing function prototypes seen with W=1 (Arnd Bergmann)

   - Fix strscpy() kerndoc typo (Arne Welzel)

   - Replace strlcpy() with strscpy() across many subsystems which were
     either Acked by respective maintainers or were trivial changes that
     went ignored for multiple weeks (Azeem Shaikh)

   - Remove unneeded cc-option test for UBSAN_TRAP (Nick Desaulniers)

   - Add KUnit tests for strcat()-family

   - Enable KUnit tests of FORTIFY wrappers under UML

   - Add more complete FORTIFY protections for strlcat()

   - Add missed disabling of FORTIFY for all arch purgatories.

   - Enable -fstrict-flex-arrays=3 globally

   - Tightening UBSAN_BOUNDS when using GCC

   - Improve checkpatch to check for strcpy, strncpy, and fake flex
     arrays

   - Improve use of const variables in FORTIFY

   - Add requested struct_size_t() helper for types not pointers

   - Add __counted_by macro for annotating flexible array size members"

* tag 'hardening-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (54 commits)
  netfilter: ipset: Replace strlcpy with strscpy
  uml: Replace strlcpy with strscpy
  um: Use HOST_DIR for mrproper
  kallsyms: Replace all non-returning strlcpy with strscpy
  sh: Replace all non-returning strlcpy with strscpy
  of/flattree: Replace all non-returning strlcpy with strscpy
  sparc64: Replace all non-returning strlcpy with strscpy
  Hexagon: Replace all non-returning strlcpy with strscpy
  kobject: Use return value of strreplace()
  lib/string_helpers: Change returned value of the strreplace()
  jbd2: Avoid printing outside the boundary of the buffer
  checkpatch: Check for 0-length and 1-element arrays
  riscv/purgatory: Do not use fortified string functions
  s390/purgatory: Do not use fortified string functions
  x86/purgatory: Do not use fortified string functions
  acpi: Replace struct acpi_table_slit 1-element array with flex-array
  clocksource: Replace all non-returning strlcpy with strscpy
  string: use __builtin_memcpy() in strlcpy/strlcat
  staging: most: Replace all non-returning strlcpy with strscpy
  drm/i2c: tda998x: Replace all non-returning strlcpy with strscpy
  ...
2023-06-27 21:24:18 -07:00
Jiri Olsa
5f81018753 fprobe: Release rethook after the ftrace_ops is unregistered
While running bpf selftests it's possible to get following fault:

  general protection fault, probably for non-canonical address \
  0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC NOPTI
  ...
  Call Trace:
   <TASK>
   fprobe_handler+0xc1/0x270
   ? __pfx_bpf_testmod_init+0x10/0x10
   ? __pfx_bpf_testmod_init+0x10/0x10
   ? bpf_fentry_test1+0x5/0x10
   ? bpf_fentry_test1+0x5/0x10
   ? bpf_testmod_init+0x22/0x80
   ? do_one_initcall+0x63/0x2e0
   ? rcu_is_watching+0xd/0x40
   ? kmalloc_trace+0xaf/0xc0
   ? do_init_module+0x60/0x250
   ? __do_sys_finit_module+0xac/0x120
   ? do_syscall_64+0x37/0x90
   ? entry_SYSCALL_64_after_hwframe+0x72/0xdc
   </TASK>

In unregister_fprobe function we can't release fp->rethook while it's
possible there are some of its users still running on another cpu.

Moving rethook_free call after fp->ops is unregistered with
unregister_ftrace_function call.

Link: https://lore.kernel.org/all/20230615115236.3476617-1-jolsa@kernel.org/

Fixes: 5b0ab78998 ("fprobe: Add exit_handler support")
Cc: stable@vger.kernel.org
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-27 23:38:31 +09:00
Linus Torvalds
3eccc0c886 for-6.5/splice-2023-06-23
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Merge tag 'for-6.5/splice-2023-06-23' of git://git.kernel.dk/linux

Pull splice updates from Jens Axboe:
 "This kills off ITER_PIPE to avoid a race between truncate,
  iov_iter_revert() on the pipe and an as-yet incomplete DMA to a bio
  with unpinned/unref'ed pages from an O_DIRECT splice read. This causes
  memory corruption.

  Instead, we either use (a) filemap_splice_read(), which invokes the
  buffered file reading code and splices from the pagecache into the
  pipe; (b) copy_splice_read(), which bulk-allocates a buffer, reads
  into it and then pushes the filled pages into the pipe; or (c) handle
  it in filesystem-specific code.

  Summary:

   - Rename direct_splice_read() to copy_splice_read()

   - Simplify the calculations for the number of pages to be reclaimed
     in copy_splice_read()

   - Turn do_splice_to() into a helper, vfs_splice_read(), so that it
     can be used by overlayfs and coda to perform the checks on the
     lower fs

   - Make vfs_splice_read() jump to copy_splice_read() to handle
     direct-I/O and DAX

   - Provide shmem with its own splice_read to handle non-existent pages
     in the pagecache. We don't want a ->read_folio() as we don't want
     to populate holes, but filemap_get_pages() requires it

   - Provide overlayfs with its own splice_read to call down to a lower
     layer as overlayfs doesn't provide ->read_folio()

   - Provide coda with its own splice_read to call down to a lower layer
     as coda doesn't provide ->read_folio()

   - Direct ->splice_read to copy_splice_read() in tty, procfs, kernfs
     and random files as they just copy to the output buffer and don't
     splice pages

   - Provide wrappers for afs, ceph, ecryptfs, ext4, f2fs, nfs, ntfs3,
     ocfs2, orangefs, xfs and zonefs to do locking and/or revalidation

   - Make cifs use filemap_splice_read()

   - Replace pointers to generic_file_splice_read() with pointers to
     filemap_splice_read() as DIO and DAX are handled in the caller;
     filesystems can still provide their own alternate ->splice_read()
     op

   - Remove generic_file_splice_read()

   - Remove ITER_PIPE and its paraphernalia as generic_file_splice_read
     was the only user"

* tag 'for-6.5/splice-2023-06-23' of git://git.kernel.dk/linux: (31 commits)
  splice: kdoc for filemap_splice_read() and copy_splice_read()
  iov_iter: Kill ITER_PIPE
  splice: Remove generic_file_splice_read()
  splice: Use filemap_splice_read() instead of generic_file_splice_read()
  cifs: Use filemap_splice_read()
  trace: Convert trace/seq to use copy_splice_read()
  zonefs: Provide a splice-read wrapper
  xfs: Provide a splice-read wrapper
  orangefs: Provide a splice-read wrapper
  ocfs2: Provide a splice-read wrapper
  ntfs3: Provide a splice-read wrapper
  nfs: Provide a splice-read wrapper
  f2fs: Provide a splice-read wrapper
  ext4: Provide a splice-read wrapper
  ecryptfs: Provide a splice-read wrapper
  ceph: Provide a splice-read wrapper
  afs: Provide a splice-read wrapper
  9p: Add splice_read wrapper
  net: Make sock_splice_read() use copy_splice_read() by default
  tty, proc, kernfs, random: Use copy_splice_read()
  ...
2023-06-26 11:52:12 -07:00
Andrew Morton
63773d2b59 Merge mm-hotfixes-stable into mm-stable to pick up depended-upon changes. 2023-06-23 16:58:19 -07:00
Masami Hiramatsu (Google)
53431798f4 tracing/probes: Fix tracepoint event with $arg* to fetch correct argument
To hide the first dummy 'data' argument on the tracepoint probe events,
the BTF argument array was modified (skip the first argument for tracepoint),
but the '$arg*' meta argument parser missed that.

Fix to increment the argument index if it is tracepoint probe. And decrement
the index when searching the type of the argument.

Link: https://lore.kernel.org/all/168657113778.3038017.12245893750241701312.stgit@mhiramat.roam.corp.google.com/

Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-23 17:35:49 +09:00
Masami Hiramatsu (Google)
ed5f297802 tracing/probes: Fix to return NULL and keep using current argc
Fix to return NULL and keep using current argc when there is
$argN and the BTF is not available.

Link: https://lore.kernel.org/all/168584574094.2056209.2694238431743782342.stgit@mhiramat.roam.corp.google.com/

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202306030940.Cej2JoUx-lkp@intel.com/
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-23 17:35:49 +09:00
Jakub Kicinski
a7384f3918 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

tools/testing/selftests/net/fcnal-test.sh
  d7a2fc1437 ("selftests: net: fcnal-test: check if FIPS mode is enabled")
  dd017c72dd ("selftests: fcnal: Test SO_DONTROUTE on TCP sockets.")
https://lore.kernel.org/all/5007b52c-dd16-dbf6-8d64-b9701bfa498b@tessares.net/
https://lore.kernel.org/all/20230619105427.4a0df9b3@canb.auug.org.au/

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-22 18:40:38 -07:00
Azeem Shaikh
38638ffa60 tracing/boot: Replace strlcpy with strscpy
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().

Direct replacement is safe here since return value of -E2BIG
is used to check for truncation instead of sizeof(dest).

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Link: https://lore.kernel.org/linux-trace-kernel/20230613004125.3539934-1-azeemshaikh38@gmail.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-22 10:39:56 -04:00
Daniel Bristot de Oliveira
e88ed227f6 tracing/timerlat: Add user-space interface
Going a step further, we propose a way to use any user-space
workload as the task waiting for the timerlat timer. This is done
via a per-CPU file named osnoise/cpu$id/timerlat_fd file.

The tracef_fd allows a task to open at a time. When a task reads
the file, the timerlat timer is armed for future osnoise/timerlat_period_us
time. When the timer fires, it prints the IRQ latency and
wakes up the user-space thread waiting in the timerlat_fd.

The thread then starts to run, executes the timerlat measurement, prints
the thread scheduling latency and returns to user-space.

When the thread rereads the timerlat_fd, the tracer will print the
user-ret(urn) latency, which is an additional metric.

This additional metric is also traced by the tracer and can be used, for
example of measuring the context switch overhead from kernel-to-user and
user-to-kernel, or the response time for an arbitrary execution in
user-space.

The tracer supports one thread per CPU, the thread must be pinned to
the CPU, and it cannot migrate while holding the timerlat_fd. The reason
is that the tracer is per CPU (nothing prohibits the tracer from
allowing migrations in the future). The tracer monitors the migration
of the thread and disables the tracer if detected.

The timerlat_fd is only available for opening/reading when timerlat
tracer is enabled, and NO_OSNOISE_WORKLOAD is set.

The simplest way to activate this feature from user-space is:

 -------------------------------- %< -----------------------------------
 int main(void)
 {
	char buffer[1024];
	int timerlat_fd;
	int retval;
	long cpu = 0;	/* place in CPU 0 */
	cpu_set_t set;

	CPU_ZERO(&set);
	CPU_SET(cpu, &set);

	if (sched_setaffinity(gettid(), sizeof(set), &set) == -1)
		return 1;

	snprintf(buffer, sizeof(buffer),
		"/sys/kernel/tracing/osnoise/per_cpu/cpu%ld/timerlat_fd",
		cpu);

	timerlat_fd = open(buffer, O_RDONLY);
	if (timerlat_fd < 0) {
		printf("error opening %s: %s\n", buffer, strerror(errno));
		exit(1);
	}

	for (;;) {
		retval = read(timerlat_fd, buffer, 1024);
		if (retval < 0)
			break;
	}

	close(timerlat_fd);
	exit(0);
}
 -------------------------------- >% -----------------------------------

When disabling timerlat, if there is a workload holding the timerlat_fd,
the SIGKILL will be sent to the thread.

Link: https://lkml.kernel.org/r/69fe66a863d2792ff4c3a149bf9e32e26468bb3a.1686063934.git.bristot@kernel.org

Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: William White <chwhite@redhat.com>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-22 10:39:56 -04:00
Daniel Bristot de Oliveira
cb7ca871c8 tracing/osnoise: Skip running osnoise if all instances are off
In the case of all tracing instances being off, sleep for the entire
period.

 Q: Why not kill all threads so?
 A: It is valid and useful to start the threads with tracing off.
For example, rtla disables tracing, starts the tracer, applies the
scheduling setup to the threads, e.g., sched priority and cgroup,
and then begin tracing with all set.

Skipping the period helps to speed up rtla setup and save the
trace after a stop tracing.

Link: https://lkml.kernel.org/r/aa4dd9b7e76fcb63901fe5407e15ec002b318599.1686063934.git.bristot@kernel.org

Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: William White <chwhite@redhat.com>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-22 10:39:56 -04:00
Daniel Bristot de Oliveira
4998e7fda1 tracing/osnoise: Switch from PF_NO_SETAFFINITY to migrate_disable
Currently, osnoise/timerlat threads run with PF_NO_SETAFFINITY set.
It works well, however, cgroups do not allow PF_NO_SETAFFINITY threads
to be accepted, and this creates a limitation to osnoise/timerlat.

To avoid this limitation, disable migration of the threads as soon
as they start to run, and then clean the PF_NO_SETAFFINITY flag (still)
used during thread creation.

If for some reason a thread migration is requested, e.g., via
sched_settafinity, the tracer thread will notice and exit.

Link: https://lkml.kernel.org/r/8ba8bc9c15b3ea40cf73cf67a9bc061a264609f0.1686063934.git.bristot@kernel.org

Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: William White <chwhite@redhat.com>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-22 10:39:56 -04:00
Jiri Olsa
83f74441bc ftrace: Show all functions with addresses in available_filter_functions_addrs
Adding new available_filter_functions_addrs file that shows all available
functions (same as available_filter_functions) together with addresses,
like:

  # cat available_filter_functions_addrs | head
  ffffffff81000770 __traceiter_initcall_level
  ffffffff810007c0 __traceiter_initcall_start
  ffffffff81000810 __traceiter_initcall_finish
  ffffffff81000860 trace_initcall_finish_cb
  ...

Note displayed address is the patch-site address and can differ from
/proc/kallsyms address.

It's useful to have address avilable for traceable symbols, so we don't
need to allways cross check kallsyms with available_filter_functions
(or the other way around) and have all the data in single file.

For backwards compatibility reasons we can't change the existing
available_filter_functions file output, but we need to add new file.

The problem is that we need to do 2 passes:

 - through available_filter_functions and find out if the function is traceable
 - through /proc/kallsyms to get the address for traceable function

Having available_filter_functions symbols together with addresses allow
us to skip the kallsyms step and we are ok with the address in
available_filter_functions_addr not being the function entry, because
kprobe_multi uses fprobe and that handles both entry and patch-site
address properly.

We have 2 interfaces how to create kprobe_multi link:

  a) passing symbols to kernel

     1) user gathers symbols and need to ensure that they are
        trace-able -> pass through available_filter_functions file

     2) kernel takes those symbols and translates them to addresses
        through kallsyms api

     3) addresses are passed to fprobe/ftrace through:

         register_fprobe_ips
         -> ftrace_set_filter_ips

  b) passing addresses to kernel

     1) user gathers symbols and needs to ensure that they are
        trace-able -> pass through available_filter_functions file

     2) user takes those symbols and translates them to addresses
       through /proc/kallsyms

     3) addresses are passed to the kernel and kernel calls:

         register_fprobe_ips
         -> ftrace_set_filter_ips

The new available_filter_functions_addrs file helps us with option b),
because we can make 'b 1' and 'b 2' in one step - while filtering traceable
functions, we get the address directly.

Link: https://lore.kernel.org/linux-trace-kernel/20230611130029.1202298-1-jolsa@kernel.org

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Tested-by: Jackie Liu <liuyun01@kylinos.cn> # x86
Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-22 10:39:16 -04:00
Donglin Peng
a1be9ccc57 function_graph: Support recording and printing the return value of function
Analyzing system call failures with the function_graph tracer can be a
time-consuming process, particularly when locating the kernel function
that first returns an error in the trace logs. This change aims to
simplify the process by recording the function return value to the
'retval' member of 'ftrace_graph_ret' and printing it when outputting
the trace log.

We have introduced new trace options: funcgraph-retval and
funcgraph-retval-hex. The former controls whether to display the return
value, while the latter controls the display format.

Please note that even if a function's return type is void, a return
value will still be printed. You can simply ignore it.

This patch only establishes the fundamental infrastructure. Subsequent
patches will make this feature available on some commonly used processor
architectures.

Here is an example:

I attempted to attach the demo process to a cpu cgroup, but it failed:

echo `pidof demo` > /sys/fs/cgroup/cpu/test/tasks
-bash: echo: write error: Invalid argument

The strace logs indicate that the write system call returned -EINVAL(-22):
...
write(1, "273\n", 4)                    = -1 EINVAL (Invalid argument)
...

To capture trace logs during a write system call, use the following
commands:

cd /sys/kernel/debug/tracing/
echo 0 > tracing_on
echo > trace
echo *sys_write > set_graph_function
echo *spin* > set_graph_notrace
echo *rcu* >> set_graph_notrace
echo *alloc* >> set_graph_notrace
echo preempt* >> set_graph_notrace
echo kfree* >> set_graph_notrace
echo $$ > set_ftrace_pid
echo function_graph > current_tracer
echo 1 > options/funcgraph-retval
echo 0 > options/funcgraph-retval-hex
echo 1 > tracing_on
echo `pidof demo` > /sys/fs/cgroup/cpu/test/tasks
echo 0 > tracing_on
cat trace > ~/trace.log

To locate the root cause, search for error code -22 directly in the file
trace.log and identify the first function that returned -22. Once you
have identified this function, examine its code to determine the root
cause.

For example, in the trace log below, cpu_cgroup_can_attach
returned -22 first, so we can focus our analysis on this function to
identify the root cause.

...

 1)          | cgroup_migrate() {
 1) 0.651 us |   cgroup_migrate_add_task(); /* = 0xffff93fcfd346c00 */
 1)          |   cgroup_migrate_execute() {
 1)          |     cpu_cgroup_can_attach() {
 1)          |       cgroup_taskset_first() {
 1) 0.732 us |         cgroup_taskset_next(); /* = 0xffff93fc8fb20000 */
 1) 1.232 us |       } /* cgroup_taskset_first = 0xffff93fc8fb20000 */
 1) 0.380 us |       sched_rt_can_attach(); /* = 0x0 */
 1) 2.335 us |     } /* cpu_cgroup_can_attach = -22 */
 1) 4.369 us |   } /* cgroup_migrate_execute = -22 */
 1) 7.143 us | } /* cgroup_migrate = -22 */

...

Link: https://lkml.kernel.org/r/1fc502712c981e0e6742185ba242992170ac9da8.1680954589.git.pengdonglin@sangfor.com.cn

Tested-by: Florian Kauer <florian.kauer@linutronix.de>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-20 18:38:37 -04:00
Steven Rostedt (Google)
f3d40e6545 fgraph: Add declaration of "struct fgraph_ret_regs"
In final testing of:

  1fc502712c.1680954589.git.pengdonglin@sangfor.com.cn/
  "function_graph: Support recording and printing the return value of function"

The test failed due to a new warning found in the build:

kernel/trace/fgraph.c:243:56: warning: ‘struct fgraph_ret_regs’ declared inside parameter list will not be visible outside of this definition or declaration

Instead of asking to send another patch series, just add it and then apply
the updates.

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-20 18:34:55 -04:00
Linus Torvalds
2e30b97343 Tracing fixes for 6.4:
- Fix MAINTAINERS file to point to proper mailing list for rtla and rv
     The mailing list pointed to linux-trace-devel instead of
     linux-trace-kernel. The former is for the tracing libraries
     and the latter is for anything in the Linux kernel tree.
     The wrong mailing list was used because linux-trace-kernel did not
     exist when rtla and rv were created.
 
  - User events:
    . Fix matching of dynamic events to their user events
      When user writes to dynamic_events file, a lookup of the
      registered dynamic events are made, but there were some cases
      that a match could be incorrectly made.
 
    . Add auto cleanup of user events
      Have the user events automatically get removed when the last
      reference (file descriptor) is closed. This was asked for to
      prevent leaks of user events hanging around needing admins
      to clean them up.
 
    . Add persistent logic (but not let user space use it yet)
      In some cases, having a persistent user event (one that does not
      get cleaned up automatically) is useful. But there's still
      debates about how to expose this to user space. The infrastructure
      is added, but the API is not.
 
    . Update the selftests
      Update the user event selftests to reflect the above changes.
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Merge tag 'trace-v6.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix MAINTAINERS file to point to proper mailing list for rtla and rv

   The mailing list pointed to linux-trace-devel instead of
   linux-trace-kernel. The former is for the tracing libraries and the
   latter is for anything in the Linux kernel tree. The wrong mailing
   list was used because linux-trace-kernel did not exist when rtla and
   rv were created.

 - User events:

    - Fix matching of dynamic events to their user events

      When user writes to dynamic_events file, a lookup of the
      registered dynamic events is made, but there were some cases that
      a match could be incorrectly made.

    - Add auto cleanup of user events

      Have the user events automatically get removed when the last
      reference (file descriptor) is closed. This was asked for to
      prevent leaks of user events hanging around needing admins to
      clean them up.

    - Add persistent logic (but not let user space use it yet)

      In some cases, having a persistent user event (one that does not
      get cleaned up automatically) is useful. But there's still debates
      about how to expose this to user space. The infrastructure is
      added, but the API is not.

    - Update the selftests

      Update the user event selftests to reflect the above changes"

* tag 'trace-v6.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/user_events: Document auto-cleanup and remove dyn_event refs
  selftests/user_events: Adapt dyn_test to non-persist events
  selftests/user_events: Ensure auto cleanup works as expected
  tracing/user_events: Add auto cleanup and future persist flag
  tracing/user_events: Track refcount consistently via put/get
  tracing/user_events: Store register flags on events
  tracing/user_events: Remove user_ns walk for groups
  selftests/user_events: Add perf self-test for empty arguments events
  selftests/user_events: Clear the events after perf self-test
  selftests/user_events: Add ftrace self-test for empty arguments events
  tracing/user_events: Fix the incorrect trace record for empty arguments events
  tracing: Modify print_fields() for fields output order
  tracing/user_events: Handle matching arguments that is null from dyn_events
  tracing/user_events: Prevent same name but different args event
  tracing/rv/rtla: Update MAINTAINERS file to point to proper mailing list
2023-06-20 15:01:08 -07:00
Beau Belgrave
a65442edb4 tracing/user_events: Add auto cleanup and future persist flag
Currently user events need to be manually deleted via the delete IOCTL
call or via the dynamic_events file. Most operators and processes wish
to have these events auto cleanup when they are no longer used by
anything to prevent them piling without manual maintenance. However,
some operators may not want this, such as pre-registering events via the
dynamic_events tracefs file.

Update user_event_put() to attempt an auto delete of the event if it's
the last reference. The auto delete must run in a work queue to ensure
proper behavior of class->reg() invocations that don't expect the call
to go away from underneath them during the unregister. Add work_struct
to user_event struct to ensure we can do this reliably.

Add a persist flag, that is not yet exposed, to ensure we can toggle
between auto-cleanup and leaving the events existing in the future. When
a non-zero flag is seen during register, return -EINVAL to ensure ABI
is clear for the user processes while we work out the best approach for
persistent events.

Link: https://lkml.kernel.org/r/20230614163336.5797-4-beaub@linux.microsoft.com
Link: https://lore.kernel.org/linux-trace-kernel/20230518093600.3f119d68@rorschach.local.home/

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 13:43:27 -04:00
Beau Belgrave
f0dbf6fd0b tracing/user_events: Track refcount consistently via put/get
Various parts of the code today track user_event's refcnt field directly
via a refcount_add/dec. This makes it hard to modify the behavior of the
last reference decrement in all code paths consistently. For example, in
the future we will auto-delete events upon the last reference going
away. This last reference could happen in many places, but we want it to
be consistently handled.

Add user_event_get() and user_event_put() for the add/dec. Update all
places where direct refcounts are being used to utilize these new
functions. In each location pass if event_mutex is locked or not. This
allows us to drop events automatically in future patches clearly. Ensure
when caller states the lock is held, it really is (or is not) held.

Link: https://lkml.kernel.org/r/20230614163336.5797-3-beaub@linux.microsoft.com

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 13:43:26 -04:00
Beau Belgrave
b08d725805 tracing/user_events: Store register flags on events
Currently we don't have any available flags for user processes to use to
indicate options for user_events. We will soon have a flag to indicate
the event should or should not auto-delete once it's not being used by
anyone.

Add a reg_flags field to user_events and parameters to existing
functions to allow for this in future patches.

Link: https://lkml.kernel.org/r/20230614163336.5797-2-beaub@linux.microsoft.com

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 13:43:26 -04:00
Beau Belgrave
ed0e0ae0c9 tracing/user_events: Remove user_ns walk for groups
During discussions it was suggested that user_ns is not a good place to
try to attach a tracing namespace. The current code has stubs to enable
that work that are very likely to change and incur a performance cost.

Remove the user_ns walk when creating a group and determining the system
name to use, since it's unlikely user_ns will be used in the future.

Link: https://lore.kernel.org/all/20230601-urenkel-holzofen-cd9403b9cadd@brauner/
Link: https://lore.kernel.org/linux-trace-kernel/20230601224928.301-1-beaub@linux.microsoft.com

Suggested-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 12:41:53 -04:00