41859 Commits

Author SHA1 Message Date
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: 9b960a38835f ("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: 88903c464321 ("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
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 5f81018753df ("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: 5f81018753df ("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
Li zeming
ed9492dfef kernel: kprobes: Remove unnecessary ‘0’ values
it is assigned first, so it does not need to initialize the assignment.

Link: https://lore.kernel.org/all/20230711185353.3218-1-zeming@nfschina.com/

Signed-off-by: Li zeming <zeming@nfschina.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-11 00:50:51 +09:00
Li zeming
e1164787f2 kprobes: Remove unnecessary ‘NULL’ values from correct_ret_addr
The 'correct_ret_addr' pointer is always set in the later code, no need
to initialize it at definition time.

Link: https://lore.kernel.org/all/20230704194359.3124-1-zeming@nfschina.com/

Signed-off-by: Li zeming <zeming@nfschina.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-11 00:50:35 +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: 3cc4e2c5fbae ("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: 7491e2c44278 ("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
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: 5b0ab78998e3 ("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
afa4bb778e workqueue: clean up WORK_* constant types, clarify masking
Dave Airlie reports that gcc-13.1.1 has started complaining about some
of the workqueue code in 32-bit arm builds:

  kernel/workqueue.c: In function ‘get_work_pwq’:
  kernel/workqueue.c:713:24: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
    713 |                 return (void *)(data & WORK_STRUCT_WQ_DATA_MASK);
        |                        ^
  [ ... a couple of other cases ... ]

and while it's not immediately clear exactly why gcc started complaining
about it now, I suspect it's some C23-induced enum type handlign fixup in
gcc-13 is the cause.

Whatever the reason for starting to complain, the code and data types
are indeed disgusting enough that the complaint is warranted.

The wq code ends up creating various "helper constants" (like that
WORK_STRUCT_WQ_DATA_MASK) using an enum type, which is all kinds of
confused.  The mask needs to be 'unsigned long', not some unspecified
enum type.

To make matters worse, the actual "mask and cast to a pointer" is
repeated a couple of times, and the cast isn't even always done to the
right pointer, but - as the error case above - to a 'void *' with then
the compiler finishing the job.

That's now how we roll in the kernel.

So create the masks using the proper types rather than some ambiguous
enumeration, and use a nice helper that actually does the type
conversion in one well-defined place.

Incidentally, this magically makes clang generate better code.  That,
admittedly, is really just a sign of clang having been seriously
confused before, and cleaning up the typing unconfuses the compiler too.

Reported-by: Dave Airlie <airlied@gmail.com>
Link: https://lore.kernel.org/lkml/CAPM=9twNnV4zMCvrPkw3H-ajZOH-01JVh_kDrxdPYQErz8ZTdA@mail.gmail.com/
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-06-23 12:08:14 -07:00
Linus Torvalds
8a28a0b6f1 Networking fixes for 6.4-rc8, including fixes from ipsec, bpf,
mptcp and netfilter.
 
 Current release - regressions:
 
   - netfilter: add NFT_TRANS_PREPARE_ERROR to deal with bound set/chain
 
   - eth: mlx5e:
     - fix scheduling of IPsec ASO query while in atomic
     - free IRQ rmap and notifier on kernel shutdown
 
 Current release - new code bugs:
 
   - phy: manual remove LEDs to ensure correct ordering
 
 Previous releases - regressions:
 
   - mptcp: fix possible divide by zero in recvmsg()
 
   - dsa: revert "net: phy: dp83867: perform soft reset and retain established link"
 
 Previous releases - always broken:
 
   - sched: netem: acquire qdisc lock in netem_change()
 
   - bpf:
     - fix verifier id tracking of scalars on spill
     - fix NULL dereference on exceptions
     - accept function names that contain dots
 
   - netfilter: disallow element updates of bound anonymous sets
 
   - mptcp: ensure listener is unhashed before updating the sk status
 
   - xfrm:
     - add missed call to delete offloaded policies
     - fix inbound ipv4/udp/esp packets to UDPv6 dualstack sockets
 
   - selftests: fixes for FIPS mode
 
   - dsa: mt7530: fix multiple CPU ports, BPDU and LLDP handling
 
   - eth: sfc: use budget for TX completions
 
 Misc:
 
   - wifi: iwlwifi: add support for SO-F device with PCI id 0x7AF0
 
 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'net-6.4-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Paolo Abeni:
 "Including fixes from ipsec, bpf, mptcp and netfilter.

  Current release - regressions:

   - netfilter: add NFT_TRANS_PREPARE_ERROR to deal with bound set/chain

   - eth: mlx5e:
      - fix scheduling of IPsec ASO query while in atomic
      - free IRQ rmap and notifier on kernel shutdown

  Current release - new code bugs:

   - phy: manual remove LEDs to ensure correct ordering

  Previous releases - regressions:

   - mptcp: fix possible divide by zero in recvmsg()

   - dsa: revert "net: phy: dp83867: perform soft reset and retain
     established link"

  Previous releases - always broken:

   - sched: netem: acquire qdisc lock in netem_change()

   - bpf:
      - fix verifier id tracking of scalars on spill
      - fix NULL dereference on exceptions
      - accept function names that contain dots

   - netfilter: disallow element updates of bound anonymous sets

   - mptcp: ensure listener is unhashed before updating the sk status

   - xfrm:
      - add missed call to delete offloaded policies
      - fix inbound ipv4/udp/esp packets to UDPv6 dualstack sockets

   - selftests: fixes for FIPS mode

   - dsa: mt7530: fix multiple CPU ports, BPDU and LLDP handling

   - eth: sfc: use budget for TX completions

  Misc:

   - wifi: iwlwifi: add support for SO-F device with PCI id 0x7AF0"

* tag 'net-6.4-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (74 commits)
  revert "net: align SO_RCVMARK required privileges with SO_MARK"
  net: wwan: iosm: Convert single instance struct member to flexible array
  sch_netem: acquire qdisc lock in netem_change()
  selftests: forwarding: Fix race condition in mirror installation
  wifi: mac80211: report all unusable beacon frames
  mptcp: ensure listener is unhashed before updating the sk status
  mptcp: drop legacy code around RX EOF
  mptcp: consolidate fallback and non fallback state machine
  mptcp: fix possible list corruption on passive MPJ
  mptcp: fix possible divide by zero in recvmsg()
  mptcp: handle correctly disconnect() failures
  bpf: Force kprobe multi expected_attach_type for kprobe_multi link
  bpf/btf: Accept function names that contain dots
  Revert "net: phy: dp83867: perform soft reset and retain established link"
  net: mdio: fix the wrong parameters
  netfilter: nf_tables: Fix for deleting base chains with payload
  netfilter: nfnetlink_osf: fix module autoload
  netfilter: nf_tables: drop module reference after updating chain
  netfilter: nf_tables: disallow timeout for anonymous sets
  netfilter: nf_tables: disallow updates of anonymous sets
  ...
2023-06-22 17:59:51 -07:00
Linus Torvalds
5950a0066f cgroup: Fixes for v6.4-rc7
It's late but here are two bug fixes. Both fix problems which can be severe
 but are very confined in scope. The risk to most use cases should be
 minimal.
 
 * Fix for an old bug which triggers if a cgroup subsystem is remounted to a
   different hierarchy while someone is reading its cgroup.procs/tasks file.
   The risk is pretty low given how seldom cgroup subsystems are moved across
   hierarchies.
 
 * We moved cpus_read_lock() outside of cgroup internal locks a while ago but
   forgot to update the legacy_freezer leading to lockdep triggers. Fixed.
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Merge tag 'cgroup-for-6.4-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup fixes from Tejun Heo:
 "It's late but here are two bug fixes. Both fix problems which can be
  severe but are very confined in scope. The risk to most use cases
  should be minimal.

   - Fix for an old bug which triggers if a cgroup subsystem is
     remounted to a different hierarchy while someone is reading its
     cgroup.procs/tasks file. The risk is pretty low given how seldom
     cgroup subsystems are moved across hierarchies.

   - We moved cpus_read_lock() outside of cgroup internal locks a while
     ago but forgot to update the legacy_freezer leading to lockdep
     triggers. Fixed"

* tag 'cgroup-for-6.4-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: Do not corrupt task iteration when rebinding subsystem
  cgroup,freezer: hold cpu_hotplug_lock before freezer_mutex in freezer_css_{online,offline}()
2023-06-22 17:27:16 -07:00
Jakub Kicinski
59bb14bda2 bpf-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2023-06-21

We've added 7 non-merge commits during the last 14 day(s) which contain
a total of 7 files changed, 181 insertions(+), 15 deletions(-).

The main changes are:

1) Fix a verifier id tracking issue with scalars upon spill,
   from Maxim Mikityanskiy.

2) Fix NULL dereference if an exception is generated while a BPF
   subprogram is running, from Krister Johansen.

3) Fix a BTF verification failure when compiling kernel with LLVM_IAS=0,
   from Florent Revest.

4) Fix expected_attach_type enforcement for kprobe_multi link,
   from Jiri Olsa.

5) Fix a bpf_jit_dump issue for x86_64 to pick the correct JITed image,
   from Yonghong Song.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Force kprobe multi expected_attach_type for kprobe_multi link
  bpf/btf: Accept function names that contain dots
  selftests/bpf: add a test for subprogram extables
  bpf: ensure main program has an extable
  bpf: Fix a bpf_jit_dump issue for x86_64 with sysctl bpf_jit_enable.
  selftests/bpf: Add test cases to assert proper ID tracking on spill
  bpf: Fix verifier id tracking of scalars on spill
====================

Link: https://lore.kernel.org/r/20230621101116.16122-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21 13:59:46 -07:00
Linus Torvalds
dad9774dea A single regression fix for a regression fix:
For a long time the tick was aligned to clock MONOTONIC so that the tick
   event happened at a multiple of nanoseconds per tick starting from clock
   MONOTONIC = 0.
 
   At some point this changed as the refined jiffies clocksource which is
   used during boot before the TSC or other clocksources becomes usable, was
   adjusted with a boot offset, so that time 0 is closer to the point where
   the kernel starts.
 
   This broke the assumption in the tick code that when the tick setup
   happens early on ktime_get() will return a multiple of nanoseconds per
   tick. As a consequence applications which aligned their periodic
   execution so that it does not collide with the tick were not longer
   guaranteed that the tick period starts from time 0.
 
   The fix for this regression was to realign the tick when it is initially
   set up to a multiple of tick periods. That works as long as the
   underlying tick device supports periodic mode, but breaks under certain
   conditions when the tick device supports only one shot mode.
 
   Depending on the offset, the alignment delta to clock MONOTONIC can get
   in a range where the minimal programming delta of the underlying clock
   event device is larger than the calculated delta to the next tick. This
   results in a boot hang as the tick code tries to play catch up, but as
   the tick never fires jiffies are not advanced so it keeps trying for
   ever.
 
   Solve this by moving the tick alignement into the NOHZ / HIGHRES
   enablement code because at that point it is guaranteed that the
   underlying clocksource is high resolution capable and not longer
   depending on the tick.
 
   This is far before user space starts, so at the point where applications
   try to align their timers, the old behaviour of the tick happening at a
   multiple of nanoseconds per tick starting from clock MONOTONIC = 0 is
   restored.
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Merge tag 'timers-urgent-2023-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
 "A single regression fix for a regression fix:

  For a long time the tick was aligned to clock MONOTONIC so that the
  tick event happened at a multiple of nanoseconds per tick starting
  from clock MONOTONIC = 0.

  At some point this changed as the refined jiffies clocksource which is
  used during boot before the TSC or other clocksources becomes usable,
  was adjusted with a boot offset, so that time 0 is closer to the point
  where the kernel starts.

  This broke the assumption in the tick code that when the tick setup
  happens early on ktime_get() will return a multiple of nanoseconds per
  tick. As a consequence applications which aligned their periodic
  execution so that it does not collide with the tick were not longer
  guaranteed that the tick period starts from time 0.

  The fix for this regression was to realign the tick when it is
  initially set up to a multiple of tick periods. That works as long as
  the underlying tick device supports periodic mode, but breaks under
  certain conditions when the tick device supports only one shot mode.

  Depending on the offset, the alignment delta to clock MONOTONIC can
  get in a range where the minimal programming delta of the underlying
  clock event device is larger than the calculated delta to the next
  tick. This results in a boot hang as the tick code tries to play catch
  up, but as the tick never fires jiffies are not advanced so it keeps
  trying for ever.

  Solve this by moving the tick alignement into the NOHZ / HIGHRES
  enablement code because at that point it is guaranteed that the
  underlying clocksource is high resolution capable and not longer
  depending on the tick.

  This is far before user space starts, so at the point where
  applications try to align their timers, the old behaviour of the tick
  happening at a multiple of nanoseconds per tick starting from clock
  MONOTONIC = 0 is restored"

* tag 'timers-urgent-2023-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick/common: Align tick period during sched_timer setup
2023-06-21 12:36:34 -07:00
Jiri Olsa
db8eae6bc5 bpf: Force kprobe multi expected_attach_type for kprobe_multi link
We currently allow to create perf link for program with
expected_attach_type == BPF_TRACE_KPROBE_MULTI.

This will cause crash when we call helpers like get_attach_cookie or
get_func_ip in such program, because it will call the kprobe_multi's
version (current->bpf_ctx context setup) of those helpers while it
expects perf_link's current->bpf_ctx context setup.

Making sure that we use BPF_TRACE_KPROBE_MULTI expected_attach_type
only for programs attaching through kprobe_multi link.

Fixes: ca74823c6e16 ("bpf: Add cookie support to programs attached with kprobe multi link")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230618131414.75649-1-jolsa@kernel.org
2023-06-21 10:40:26 +02:00
Florent Revest
9724160b39 bpf/btf: Accept function names that contain dots
When building a kernel with LLVM=1, LLVM_IAS=0 and CONFIG_KASAN=y, LLVM
leaves DWARF tags for the "asan.module_ctor" & co symbols. In turn,
pahole creates BTF_KIND_FUNC entries for these and this makes the BTF
metadata validation fail because they contain a dot.

In a dramatic turn of event, this BTF verification failure can cause
the netfilter_bpf initialization to fail, causing netfilter_core to
free the netfilter_helper hashmap and netfilter_ftp to trigger a
use-after-free. The risk of u-a-f in netfilter will be addressed
separately but the existence of "asan.module_ctor" debug info under some
build conditions sounds like a good enough reason to accept functions
that contain dots in BTF.

Although using only LLVM=1 is the recommended way to compile clang-based
kernels, users can certainly do LLVM=1, LLVM_IAS=0 as well and we still
try to support that combination according to Nick. To clarify:

  - > v5.10 kernel, LLVM=1 (LLVM_IAS=0 is not the default) is recommended,
    but user can still have LLVM=1, LLVM_IAS=0 to trigger the issue

  - <= 5.10 kernel, LLVM=1 (LLVM_IAS=0 is the default) is recommended in
    which case GNU as will be used

Fixes: 1dc92851849c ("bpf: kernel side support for BTF Var and DataSec")
Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Yonghong Song <yhs@meta.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/bpf/20230615145607.3469985-1-revest@chromium.org
2023-06-21 10:32:22 +02:00
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
Thomas Gleixner
13bb06f8dd tick/common: Align tick period during sched_timer setup
The tick period is aligned very early while the first clock_event_device is
registered. At that point the system runs in periodic mode and switches
later to one-shot mode if possible.

The next wake-up event is programmed based on the aligned value
(tick_next_period) but the delta value, that is used to program the
clock_event_device, is computed based on ktime_get().

With the subtracted offset, the device fires earlier than the exact time
frame. With a large enough offset the system programs the timer for the
next wake-up and the remaining time left is too small to make any boot
progress. The system hangs.

Move the alignment later to the setup of tick_sched timer. At this point
the system switches to oneshot mode and a high resolution clocksource is
available. At this point it is safe to align tick_next_period because
ktime_get() will now return accurate (not jiffies based) time.

[bigeasy: Patch description + testing].

Fixes: e9523a0d81899 ("tick/common: Align tick period with the HZ tick.")
Reported-by: Mathias Krause <minipli@grsecurity.net>
Reported-by: "Bhatnagar, Rishabh" <risbhat@amazon.com>
Suggested-by: Mathias Krause <minipli@grsecurity.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Tested-by: Mathias Krause <minipli@grsecurity.net>
Acked-by: SeongJae Park <sj@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/5a56290d-806e-b9a5-f37c-f21958b5a8c0@grsecurity.net
Link: https://lore.kernel.org/12c6f9a3-d087-b824-0d05-0d18c9bc1bf3@amazon.com
Link: https://lore.kernel.org/r/20230615091830.RxMV2xf_@linutronix.de
2023-06-16 20:45:28 +02:00
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
sunliming
6f05dcabe5 tracing/user_events: Fix the incorrect trace record for empty arguments events
The user_events support events that has empty arguments. But the trace event
is discarded and not really committed when the arguments is empty. Fix this
by not attempting to copy in zero-length data.

Link: https://lkml.kernel.org/r/20230606062027.1008398-2-sunliming@kylinos.cn

Acked-by: Beau Belgrave <beaub@linux.microsoft.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: sunliming <sunliming@kylinos.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 12:41:52 -04:00
sunliming
e70bb54d7a tracing: Modify print_fields() for fields output order
Now the print_fields() print trace event fields in reverse order. Modify
it to the positive sequence.

Example outputs for a user event:
	test0 u32 count1; u32 count2

Output before:
	example-2547    [000] .....   325.666387: test0: count2=0x2 (2) count1=0x1 (1)

Output after:
	example-2742    [002] .....   429.769370: test0: count1=0x1 (1) count2=0x2 (2)

Link: https://lore.kernel.org/linux-trace-kernel/20230525085232.5096-1-sunliming@kylinos.cn

Fixes: 80a76994b2d88 ("tracing: Add "fields" option to show raw trace event fields")
Signed-off-by: sunliming <sunliming@kylinos.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 12:41:52 -04:00
sunliming
cfac4ed727 tracing/user_events: Handle matching arguments that is null from dyn_events
When A registering user event from dyn_events has no argments, it will pass the
matching check, regardless of whether there is a user event with the same name
and arguments. Add the matching check when the arguments of registering user
event is null.

Link: https://lore.kernel.org/linux-trace-kernel/20230529065110.303440-1-sunliming@kylinos.cn

Signed-off-by: sunliming <sunliming@kylinos.cn>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 12:41:52 -04:00
sunliming
ba470eebc2 tracing/user_events: Prevent same name but different args event
User processes register name_args for events. If the same name but different
args event are registered. The trace outputs of second event are printed
as the first event. This is incorrect.

Return EADDRINUSE back to the user process if the same name but different args
event has being registered.

Link: https://lore.kernel.org/linux-trace-kernel/20230529032100.286534-1-sunliming@kylinos.cn

Signed-off-by: sunliming <sunliming@kylinos.cn>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-14 12:41:52 -04:00
Krister Johansen
0108a4e9f3 bpf: ensure main program has an extable
When subprograms are in use, the main program is not jit'd after the
subprograms because jit_subprogs sets a value for prog->bpf_func upon
success.  Subsequent calls to the JIT are bypassed when this value is
non-NULL.  This leads to a situation where the main program and its
func[0] counterpart are both in the bpf kallsyms tree, but only func[0]
has an extable.  Extables are only created during JIT.  Now there are
two nearly identical program ksym entries in the tree, but only one has
an extable.  Depending upon how the entries are placed, there's a chance
that a fault will call search_extable on the aux with the NULL entry.

Since jit_subprogs already copies state from func[0] to the main
program, include the extable pointer in this state duplication.
Additionally, ensure that the copy of the main program in func[0] is not
added to the bpf_prog_kallsyms table. Instead, let the main program get
added later in bpf_prog_load().  This ensures there is only a single
copy of the main program in the kallsyms table, and that its tag matches
the tag observed by tooling like bpftool.

Cc: stable@vger.kernel.org
Fixes: 1c2a088a6626 ("bpf: x64: add JIT support for multi-function programs")
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/6de9b2f4b4724ef56efbb0339daaa66c8b68b1e7.1686616663.git.kjlx@templeofstupid.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-13 15:13:52 -07:00
Linus Torvalds
fb054096ae 19 hotfixes. 14 are cc:stable and the remainder address issues which were
introduced during this -rc cycle or which were considered inappropriate
 for a backport.
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Merge tag 'mm-hotfixes-stable-2023-06-12-12-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "19 hotfixes. 14 are cc:stable and the remainder address issues which
  were introduced during this development cycle or which were considered
  inappropriate for a backport"

* tag 'mm-hotfixes-stable-2023-06-12-12-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  zswap: do not shrink if cgroup may not zswap
  page cache: fix page_cache_next/prev_miss off by one
  ocfs2: check new file size on fallocate call
  mailmap: add entry for John Keeping
  mm/damon/core: fix divide error in damon_nr_accesses_to_accesses_bp()
  epoll: ep_autoremove_wake_function should use list_del_init_careful
  mm/gup_test: fix ioctl fail for compat task
  nilfs2: reject devices with insufficient block count
  ocfs2: fix use-after-free when unmounting read-only filesystem
  lib/test_vmalloc.c: avoid garbage in page array
  nilfs2: fix possible out-of-bounds segment allocation in resize ioctl
  riscv/purgatory: remove PGO flags
  powerpc/purgatory: remove PGO flags
  x86/purgatory: remove PGO flags
  kexec: support purgatories with .text.hot sections
  mm/uffd: allow vma to merge as much as possible
  mm/uffd: fix vma operation where start addr cuts part of vma
  radix-tree: move declarations to header
  nilfs2: fix incomplete buffer cleanup in nilfs_btnode_abort_change_key()
2023-06-12 16:14:34 -07:00
Ricardo Ribalda
8652d44f46 kexec: support purgatories with .text.hot sections
Patch series "kexec: Fix kexec_file_load for llvm16 with PGO", v7.

When upreving llvm I realised that kexec stopped working on my test
platform.

The reason seems to be that due to PGO there are multiple .text sections
on the purgatory, and kexec does not supports that.


This patch (of 4):

Clang16 links the purgatory text in two sections when PGO is in use:

  [ 1] .text             PROGBITS         0000000000000000  00000040
       00000000000011a1  0000000000000000  AX       0     0     16
  [ 2] .rela.text        RELA             0000000000000000  00003498
       0000000000000648  0000000000000018   I      24     1     8
  ...
  [17] .text.hot.        PROGBITS         0000000000000000  00003220
       000000000000020b  0000000000000000  AX       0     0     1
  [18] .rela.text.hot.   RELA             0000000000000000  00004428
       0000000000000078  0000000000000018   I      24    17     8

And both of them have their range [sh_addr ... sh_addr+sh_size] on the
area pointed by `e_entry`.

This causes that image->start is calculated twice, once for .text and
another time for .text.hot. The second calculation leaves image->start
in a random location.

Because of this, the system crashes immediately after:

kexec_core: Starting new kernel

Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-0-b05c520b7296@chromium.org
Link: https://lkml.kernel.org/r/20230321-kexec_clang16-v7-1-b05c520b7296@chromium.org
Fixes: 930457057abe ("kernel/kexec_file.c: split up __kexec_load_puragory")
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Ross Zwisler <zwisler@google.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Philipp Rudo <prudo@redhat.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Rix <trix@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-12 11:31:50 -07:00
Xiu Jianfeng
6f363f5aa8 cgroup: Do not corrupt task iteration when rebinding subsystem
We found a refcount UAF bug as follows:

refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 342 at lib/refcount.c:25 refcount_warn_saturate+0xa0/0x148
Workqueue: events cpuset_hotplug_workfn
Call trace:
 refcount_warn_saturate+0xa0/0x148
 __refcount_add.constprop.0+0x5c/0x80
 css_task_iter_advance_css_set+0xd8/0x210
 css_task_iter_advance+0xa8/0x120
 css_task_iter_next+0x94/0x158
 update_tasks_root_domain+0x58/0x98
 rebuild_root_domains+0xa0/0x1b0
 rebuild_sched_domains_locked+0x144/0x188
 cpuset_hotplug_workfn+0x138/0x5a0
 process_one_work+0x1e8/0x448
 worker_thread+0x228/0x3e0
 kthread+0xe0/0xf0
 ret_from_fork+0x10/0x20

then a kernel panic will be triggered as below:

Unable to handle kernel paging request at virtual address 00000000c0000010
Call trace:
 cgroup_apply_control_disable+0xa4/0x16c
 rebind_subsystems+0x224/0x590
 cgroup_destroy_root+0x64/0x2e0
 css_free_rwork_fn+0x198/0x2a0
 process_one_work+0x1d4/0x4bc
 worker_thread+0x158/0x410
 kthread+0x108/0x13c
 ret_from_fork+0x10/0x18

The race that cause this bug can be shown as below:

(hotplug cpu)                | (umount cpuset)
mutex_lock(&cpuset_mutex)    | mutex_lock(&cgroup_mutex)
cpuset_hotplug_workfn        |
 rebuild_root_domains        |  rebind_subsystems
  update_tasks_root_domain   |   spin_lock_irq(&css_set_lock)
   css_task_iter_start       |    list_move_tail(&cset->e_cset_node[ss->id]
   while(css_task_iter_next) |                  &dcgrp->e_csets[ss->id]);
   css_task_iter_end         |   spin_unlock_irq(&css_set_lock)
mutex_unlock(&cpuset_mutex)  | mutex_unlock(&cgroup_mutex)

Inside css_task_iter_start/next/end, css_set_lock is hold and then
released, so when iterating task(left side), the css_set may be moved to
another list(right side), then it->cset_head points to the old list head
and it->cset_pos->next points to the head node of new list, which can't
be used as struct css_set.

To fix this issue, switch from all css_sets to only scgrp's css_sets to
patch in-flight iterators to preserve correct iteration, and then
update it->cset_head as well.

Reported-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Link: https://www.spinics.net/lists/cgroups/msg37935.html
Suggested-by: Michal Koutný <mkoutny@suse.com>
Link: https://lore.kernel.org/all/20230526114139.70274-1-xiujianfeng@huaweicloud.com/
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Fixes: 2d8f243a5e6e ("cgroup: implement cgroup->e_csets[]")
Cc: stable@vger.kernel.org # v3.16+
Signed-off-by: Tejun Heo <tj@kernel.org>
2023-06-12 07:21:57 -10:00
Tetsuo Handa
f0cc749254 cgroup,freezer: hold cpu_hotplug_lock before freezer_mutex in freezer_css_{online,offline}()
syzbot is again reporting circular locking dependency between
cpu_hotplug_lock and freezer_mutex. Do like what we did with
commit 57dcd64c7e036299 ("cgroup,freezer: hold cpu_hotplug_lock
before freezer_mutex").

Reported-by: syzbot <syzbot+2ab700fe1829880a2ec6@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=2ab700fe1829880a2ec6
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+2ab700fe1829880a2ec6@syzkaller.appspotmail.com>
Fixes: f5d39b020809 ("freezer,sched: Rewrite core freezer logic")
Cc: stable@vger.kernel.org # v6.1+
Signed-off-by: Tejun Heo <tj@kernel.org>
2023-06-12 06:39:48 -10:00
Linus Torvalds
dbfa18c5d7 virtio,vhost,vdpa: bugfixes
A bunch of fixes all over the place
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio bug fixes from Michael Tsirkin:
 "A bunch of fixes all over the place"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  tools/virtio: use canonical ftrace path
  vhost_vdpa: support PACKED when setting-getting vring_base
  vhost: support PACKED when setting-getting vring_base
  vhost: Fix worker hangs due to missed wake up calls
  vhost: Fix crash during early vhost_transport_send_pkt calls
  vhost_net: revert upend_idx only on retriable error
  vhost_vdpa: tell vqs about the negotiated
  vdpa/mlx5: Fix hang when cvq commands are triggered during device unregister
  tools/virtio: Add .gitignore for ringtest
  tools/virtio: Fix arm64 ringtest compilation error
  vduse: avoid empty string for dev name
  vhost: use kzalloc() instead of kmalloc() followed by memset()
2023-06-09 11:04:08 -07:00
Linus Torvalds
9cd6357f10 cgroup: Fixes for v6.4-rc5
* Fix css_set reference leaks on fork failures.
 
 * Fix CPU hotplug locking in cgroup_transfer_tasks() which is used by
   cgroup1 cpuset.
 
 * Doc update.
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Merge tag 'cgroup-for-6.4-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup fixes from Tejun Heo:

 - Fix css_set reference leaks on fork failures

 - Fix CPU hotplug locking in cgroup_transfer_tasks() which is used by
   cgroup1 cpuset

 - Doc update

* tag 'cgroup-for-6.4-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: Documentation: Clarify usage of memory limits
  cgroup: always put cset in cgroup_css_set_put_fork
  cgroup: fix missing cpus_read_{lock,unlock}() in cgroup_transfer_tasks()
2023-06-08 18:52:54 -07:00
Mike Christie
4b13cbef79 vhost: Fix worker hangs due to missed wake up calls
We can race where we have added work to the work_list, but
vhost_task_fn has passed that check but not yet set us into
TASK_INTERRUPTIBLE. wake_up_process will see us in TASK_RUNNING and
just return.

This bug was intoduced in commit f9010dbdce91 ("fork, vhost: Use
CLONE_THREAD to fix freezer/ps regression") when I moved the setting
of TASK_INTERRUPTIBLE to simplfy the code and avoid get_signal from
logging warnings about being in the wrong state. This moves the setting
of TASK_INTERRUPTIBLE back to before we test if we need to stop the
task to avoid a possible race there as well. We then have vhost_worker
set TASK_RUNNING if it finds work similar to before.

Fixes: f9010dbdce91 ("fork, vhost: Use CLONE_THREAD to fix freezer/ps regression")
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230607192338.6041-3-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-06-08 15:43:09 -04:00
Linus Torvalds
25041a4c02 Networking fixes for 6.4-rc6, including fixes from can, wifi, netfilter,
bluetooth and ebpf.
 
 Current release - regressions:
 
   - bpf: sockmap: avoid potential NULL dereference in sk_psock_verdict_data_ready()
 
   - wifi: iwlwifi: fix -Warray-bounds bug in iwl_mvm_wait_d3_notif()
 
   - phylink: actually fix ksettings_set() ethtool call
 
   - eth: dwmac-qcom-ethqos: fix a regression on EMAC < 3
 
 Current release - new code bugs:
 
   - wifi: mt76: fix possible NULL pointer dereference in mt7996_mac_write_txwi()
 
 Previous releases - regressions:
 
   - netfilter: fix NULL pointer dereference in nf_confirm_cthelper
 
   - wifi: rtw88/rtw89: correct PS calculation for SUPPORTS_DYNAMIC_PS
 
   - openvswitch: fix upcall counter access before allocation
 
   - bluetooth:
     - fix use-after-free in hci_remove_ltk/hci_remove_irk
     - fix l2cap_disconnect_req deadlock
 
   - nic: bnxt_en: prevent kernel panic when receiving unexpected PHC_UPDATE event
 
 Previous releases - always broken:
 
   - core: annotate rfs lockless accesses
 
   - sched: fq_pie: ensure reasonable TCA_FQ_PIE_QUANTUM values
 
   - netfilter: add null check for nla_nest_start_noflag() in nft_dump_basechain_hook()
 
   - bpf: fix UAF in task local storage
 
   - ipv4: ping_group_range: allow GID from 2147483648 to 4294967294
 
   - ipv6: rpl: fix route of death.
 
   - tcp: gso: really support BIG TCP
 
   - mptcp: fixes for user-space PM address advertisement
 
   - smc: avoid to access invalid RMBs' MRs in SMCRv1 ADD LINK CONT
 
   - can: avoid possible use-after-free when j1939_can_rx_register fails
 
   - batman-adv: fix UaF while rescheduling delayed work
 
   - eth: qede: fix scheduling while atomic
 
   - eth: ice: make writes to /dev/gnssX synchronous
 
 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'net-6.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Paolo Abeni:
 "Including fixes from can, wifi, netfilter, bluetooth and ebpf.

  Current release - regressions:

   - bpf: sockmap: avoid potential NULL dereference in
     sk_psock_verdict_data_ready()

   - wifi: iwlwifi: fix -Warray-bounds bug in iwl_mvm_wait_d3_notif()

   - phylink: actually fix ksettings_set() ethtool call

   - eth: dwmac-qcom-ethqos: fix a regression on EMAC < 3

  Current release - new code bugs:

   - wifi: mt76: fix possible NULL pointer dereference in
     mt7996_mac_write_txwi()

  Previous releases - regressions:

   - netfilter: fix NULL pointer dereference in nf_confirm_cthelper

   - wifi: rtw88/rtw89: correct PS calculation for SUPPORTS_DYNAMIC_PS

   - openvswitch: fix upcall counter access before allocation

   - bluetooth:
      - fix use-after-free in hci_remove_ltk/hci_remove_irk
      - fix l2cap_disconnect_req deadlock

   - nic: bnxt_en: prevent kernel panic when receiving unexpected
     PHC_UPDATE event

  Previous releases - always broken:

   - core: annotate rfs lockless accesses

   - sched: fq_pie: ensure reasonable TCA_FQ_PIE_QUANTUM values

   - netfilter: add null check for nla_nest_start_noflag() in
     nft_dump_basechain_hook()

   - bpf: fix UAF in task local storage

   - ipv4: ping_group_range: allow GID from 2147483648 to 4294967294

   - ipv6: rpl: fix route of death.

   - tcp: gso: really support BIG TCP

   - mptcp: fixes for user-space PM address advertisement

   - smc: avoid to access invalid RMBs' MRs in SMCRv1 ADD LINK CONT

   - can: avoid possible use-after-free when j1939_can_rx_register fails

   - batman-adv: fix UaF while rescheduling delayed work

   - eth: qede: fix scheduling while atomic

   - eth: ice: make writes to /dev/gnssX synchronous"

* tag 'net-6.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits)
  bnxt_en: Implement .set_port / .unset_port UDP tunnel callbacks
  bnxt_en: Prevent kernel panic when receiving unexpected PHC_UPDATE event
  bnxt_en: Skip firmware fatal error recovery if chip is not accessible
  bnxt_en: Query default VLAN before VNIC setup on a VF
  bnxt_en: Don't issue AP reset during ethtool's reset operation
  bnxt_en: Fix bnxt_hwrm_update_rss_hash_cfg()
  net: bcmgenet: Fix EEE implementation
  eth: ixgbe: fix the wake condition
  eth: bnxt: fix the wake condition
  lib: cpu_rmap: Fix potential use-after-free in irq_cpu_rmap_release()
  bpf: Add extra path pointer check to d_path helper
  net: sched: fix possible refcount leak in tc_chain_tmplt_add()
  net: sched: act_police: fix sparse errors in tcf_police_dump()
  net: openvswitch: fix upcall counter access before allocation
  net: sched: move rtm_tca_policy declaration to include file
  ice: make writes to /dev/gnssX synchronous
  net: sched: add rcu annotations around qdisc->qdisc_sleeping
  rfs: annotate lockless accesses to RFS sock flow table
  rfs: annotate lockless accesses to sk->sk_rxhash
  virtio_net: use control_buf for coalesce params
  ...
2023-06-08 09:27:19 -07:00
Maxim Mikityanskiy
713274f1f2 bpf: Fix verifier id tracking of scalars on spill
The following scenario describes a bug in the verifier where it
incorrectly concludes about equivalent scalar IDs which could lead to
verifier bypass in privileged mode:

1. Prepare a 32-bit rogue number.
2. Put the rogue number into the upper half of a 64-bit register, and
   roll a random (unknown to the verifier) bit in the lower half. The
   rest of the bits should be zero (although variations are possible).
3. Assign an ID to the register by MOVing it to another arbitrary
   register.
4. Perform a 32-bit spill of the register, then perform a 32-bit fill to
   another register. Due to a bug in the verifier, the ID will be
   preserved, although the new register will contain only the lower 32
   bits, i.e. all zeros except one random bit.

At this point there are two registers with different values but the same
ID, which means the integrity of the verifier state has been corrupted.

5. Compare the new 32-bit register with 0. In the branch where it's
   equal to 0, the verifier will believe that the original 64-bit
   register is also 0, because it has the same ID, but its actual value
   still contains the rogue number in the upper half.
   Some optimizations of the verifier prevent the actual bypass, so
   extra care is needed: the comparison must be between two registers,
   and both branches must be reachable (this is why one random bit is
   needed). Both branches are still suitable for the bypass.
6. Right shift the original register by 32 bits to pop the rogue number.
7. Use the rogue number as an offset with any pointer. The verifier will
   believe that the offset is 0, while in reality it's the given number.

The fix is similar to the 32-bit BPF_MOV handling in check_alu_op for
SCALAR_VALUE. If the spill is narrowing the actual register value, don't
keep the ID, make sure it's reset to 0.

Fixes: 354e8f1970f8 ("bpf: Support <8-byte scalar spill and refill")
Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Andrii Nakryiko <andrii@kernel.org> # Checked veristat delta
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230607123951.558971-2-maxtram95@gmail.com
2023-06-08 10:27:43 +02:00
Jakub Kicinski
c9d99cfa66 bpf-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2023-06-07

We've added 7 non-merge commits during the last 7 day(s) which contain
a total of 12 files changed, 112 insertions(+), 7 deletions(-).

The main changes are:

1) Fix a use-after-free in BPF's task local storage, from KP Singh.

2) Make struct path handling more robust in bpf_d_path, from Jiri Olsa.

3) Fix a syzbot NULL-pointer dereference in sockmap, from Eric Dumazet.

4) UAPI fix for BPF_NETFILTER before final kernel ships,
   from Florian Westphal.

5) Fix map-in-map array_map_gen_lookup code generation where elem_size was
   not being set for inner maps, from Rhys Rustad-Elliott.

6) Fix sockopt_sk selftest's NETLINK_LIST_MEMBERSHIPS assertion,
   from Yonghong Song.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Add extra path pointer check to d_path helper
  selftests/bpf: Fix sockopt_sk selftest
  bpf: netfilter: Add BPF_NETFILTER bpf_attach_type
  selftests/bpf: Add access_inner_map selftest
  bpf: Fix elem_size not being set for inner maps
  bpf: Fix UAF in task local storage
  bpf, sockmap: Avoid potential NULL dereference in sk_psock_verdict_data_ready()
====================

Link: https://lore.kernel.org/r/20230607220514.29698-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-07 21:47:11 -07:00
Jiri Olsa
f46fab0e36 bpf: Add extra path pointer check to d_path helper
Anastasios reported crash on stable 5.15 kernel with following
BPF attached to lsm hook:

  SEC("lsm.s/bprm_creds_for_exec")
  int BPF_PROG(bprm_creds_for_exec, struct linux_binprm *bprm)
  {
          struct path *path = &bprm->executable->f_path;
          char p[128] = { 0 };

          bpf_d_path(path, p, 128);
          return 0;
  }

But bprm->executable can be NULL, so bpf_d_path call will crash:

  BUG: kernel NULL pointer dereference, address: 0000000000000018
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC NOPTI
  ...
  RIP: 0010:d_path+0x22/0x280
  ...
  Call Trace:
   <TASK>
   bpf_d_path+0x21/0x60
   bpf_prog_db9cf176e84498d9_bprm_creds_for_exec+0x94/0x99
   bpf_trampoline_6442506293_0+0x55/0x1000
   bpf_lsm_bprm_creds_for_exec+0x5/0x10
   security_bprm_creds_for_exec+0x29/0x40
   bprm_execve+0x1c1/0x900
   do_execveat_common.isra.0+0x1af/0x260
   __x64_sys_execve+0x32/0x40

It's problem for all stable trees with bpf_d_path helper, which was
added in 5.9.

This issue is fixed in current bpf code, where we identify and mark
trusted pointers, so the above code would fail even to load.

For the sake of the stable trees and to workaround potentially broken
verifier in the future, adding the code that reads the path object from
the passed pointer and verifies it's valid in kernel space.

Fixes: 6e22ab9da793 ("bpf: Add d_path helper")
Reported-by: Anastasios Papagiannis <tasos.papagiannnis@gmail.com>
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230606181714.532998-1-jolsa@kernel.org
2023-06-07 15:03:43 +02:00
Florian Westphal
132328e8e8 bpf: netfilter: Add BPF_NETFILTER bpf_attach_type
Andrii Nakryiko writes:

 And we currently don't have an attach type for NETLINK BPF link.
 Thankfully it's not too late to add it. I see that link_create() in
 kernel/bpf/syscall.c just bypasses attach_type check. We shouldn't
 have done that. Instead we need to add BPF_NETLINK attach type to enum
 bpf_attach_type. And wire all that properly throughout the kernel and
 libbpf itself.

This adds BPF_NETFILTER and uses it.  This breaks uabi but this
wasn't in any non-rc release yet, so it should be fine.

v2: check link_attack prog type in link_create too

Fixes: 84601d6ee68a ("bpf: add bpf_link support for BPF_NETFILTER programs")
Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/CAEf4BzZ69YgrQW7DHCJUT_X+GqMq_ZQQPBwopaJJVGFD5=d5Vg@mail.gmail.com/
Link: https://lore.kernel.org/bpf/20230605131445.32016-1-fw@strlen.de
2023-06-05 15:01:43 -07:00
Linus Torvalds
51f269a6ec Probes fixes for 6.4-rc4:
- Return NULL if the trace_probe list on trace_probe_event is empty.
 
 - selftests/ftrace: Choose testing symbol name for filtering feature
   from sample data instead of fixed symbol.
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Merge tag 'probes-fixes-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull probes fixes from Masami Hiramatsu:

 - Return NULL if the trace_probe list on trace_probe_event is empty

 - selftests/ftrace: Choose testing symbol name for filtering feature
   from sample data instead of fixed symbol

* tag 'probes-fixes-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  selftests/ftrace: Choose target function for filter test from samples
  tracing/probe: trace_probe_primary_from_call(): checked list_first_entry
2023-06-03 08:23:16 -04:00
Rhys Rustad-Elliott
cba41bb78d bpf: Fix elem_size not being set for inner maps
Commit d937bc3449fa ("bpf: make uniform use of array->elem_size
everywhere in arraymap.c") changed array_map_gen_lookup to use
array->elem_size instead of round_up(map->value_size, 8) as the element
size when generating code to access a value in an array map.

array->elem_size, however, is not set by bpf_map_meta_alloc when
initializing an BPF_MAP_TYPE_ARRAY_OF_MAPS or BPF_MAP_TYPE_HASH_OF_MAPS.
This results in array_map_gen_lookup incorrectly outputting code that
always accesses index 0 in the array (as the index will be calculated
via a multiplication with the element size, which is incorrectly set to
0).

Set elem_size on the bpf_array object when allocating an array or hash
of maps to fix this.

Fixes: d937bc3449fa ("bpf: make uniform use of array->elem_size everywhere in arraymap.c")
Signed-off-by: Rhys Rustad-Elliott <me@rhysre.net>
Link: https://lore.kernel.org/r/20230602190110.47068-2-me@rhysre.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-06-02 16:22:12 -07:00
KP Singh
b0fd1852bc bpf: Fix UAF in task local storage
When task local storage was generalized for tracing programs, the
bpf_task_local_storage callback was moved from a BPF LSM hook
callback for security_task_free LSM hook to it's own callback. But a
failure case in bad_fork_cleanup_security was missed which, when
triggered, led to a dangling task owner pointer and a subsequent
use-after-free. Move the bpf_task_storage_free to the very end of
free_task to handle all failure cases.

This issue was noticed when a BPF LSM program was attached to the
task_alloc hook on a kernel with KASAN enabled. The program used
bpf_task_storage_get to copy the task local storage from the current
task to the new task being created.

Fixes: a10787e6d58c ("bpf: Enable task local storage for tracing programs")
Reported-by: Kuba Piecuch <jpiecuch@google.com>
Signed-off-by: KP Singh <kpsingh@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230602002612.1117381-1-kpsingh@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-06-02 10:18:07 -07:00
Linus Torvalds
c43a6ff9f9 modules-6.4-rc5-second-pull
A zstd fix by lucas as he tested zstd decompression support
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Merge tag 'modules-6.4-rc5-second-pull' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull modules fix from Luis Chamberlain:
 "A zstd fix by lucas as he tested zstd decompression support"

* tag 'modules-6.4-rc5-second-pull' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  module/decompress: Fix error checking on zstd decompression
2023-06-01 20:48:16 -04:00
Lucas De Marchi
fadb74f9f2 module/decompress: Fix error checking on zstd decompression
While implementing support for in-kernel decompression in kmod,
finit_module() was returning a very suspicious value:

	finit_module(3, "", MODULE_INIT_COMPRESSED_FILE) = 18446744072717407296

It turns out the check for module_get_next_page() failing is wrong,
and hence the decompression was not really taking place. Invert
the condition to fix it.

Fixes: 169a58ad824d ("module/decompress: Support zstd in-kernel decompression")
Cc: stable@kernel.org
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-06-01 14:36:46 -07:00
Mike Christie
f9010dbdce fork, vhost: Use CLONE_THREAD to fix freezer/ps regression
When switching from kthreads to vhost_tasks two bugs were added:
1. The vhost worker tasks's now show up as processes so scripts doing
ps or ps a would not incorrectly detect the vhost task as another
process.  2. kthreads disabled freeze by setting PF_NOFREEZE, but
vhost tasks's didn't disable or add support for them.

To fix both bugs, this switches the vhost task to be thread in the
process that does the VHOST_SET_OWNER ioctl, and has vhost_worker call
get_signal to support SIGKILL/SIGSTOP and freeze signals. Note that
SIGKILL/STOP support is required because CLONE_THREAD requires
CLONE_SIGHAND which requires those 2 signals to be supported.

This is a modified version of the patch written by Mike Christie
<michael.christie@oracle.com> which was a modified version of patch
originally written by Linus.

Much of what depended upon PF_IO_WORKER now depends on PF_USER_WORKER.
Including ignoring signals, setting up the register state, and having
get_signal return instead of calling do_group_exit.

Tidied up the vhost_task abstraction so that the definition of
vhost_task only needs to be visible inside of vhost_task.c.  Making
it easier to review the code and tell what needs to be done where.
As part of this the main loop has been moved from vhost_worker into
vhost_task_fn.  vhost_worker now returns true if work was done.

The main loop has been updated to call get_signal which handles
SIGSTOP, freezing, and collects the message that tells the thread to
exit as part of process exit.  This collection clears
__fatal_signal_pending.  This collection is not guaranteed to
clear signal_pending() so clear that explicitly so the schedule()
sleeps.

For now the vhost thread continues to exist and run work until the
last file descriptor is closed and the release function is called as
part of freeing struct file.  To avoid hangs in the coredump
rendezvous and when killing threads in a multi-threaded exec.  The
coredump code and de_thread have been modified to ignore vhost threads.

Remvoing the special case for exec appears to require teaching
vhost_dev_flush how to directly complete transactions in case
the vhost thread is no longer running.

Removing the special case for coredump rendezvous requires either the
above fix needed for exec or moving the coredump rendezvous into
get_signal.

Fixes: 6e890c5d5021 ("vhost: use vhost_tasks for worker threads")
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Co-developed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-06-01 17:15:33 -04:00
Pietro Borrello
81d0fa4cb4 tracing/probe: trace_probe_primary_from_call(): checked list_first_entry
All callers of trace_probe_primary_from_call() check the return
value to be non NULL. However, the function returns
list_first_entry(&tpe->probes, ...) which can never be NULL.
Additionally, it does not check for the list being possibly empty,
possibly causing a type confusion on empty lists.
Use list_first_entry_or_null() which solves both problems.

Link: https://lore.kernel.org/linux-trace-kernel/20230128-list-entry-null-check-v1-1-8bde6a3da2ef@diag.uniroma1.it/

Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe")
Signed-off-by: Pietro Borrello <borrello@diag.uniroma1.it>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Mukesh Ojha <quic_mojha@quicinc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-31 18:47:10 +09:00
Linus Torvalds
6d86b56f54 modules-6.4-rc5
A fix is provided for ia64. Even though ia64 is on life support it helps
 to fix issues if we can. Thanks to Linus for doing tons of the ia64
 debugging.
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Merge tag 'modules-6.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull modules fix from Luis Chamberlain:
 "A fix is provided for ia64. Even though ia64 is on life support it
  helps to fix issues if we can. Thanks to Linus for doing tons of the
  ia64 debugging"

* tag 'modules-6.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  module: fix module load for ia64
2023-05-30 15:49:40 -04:00
Song Liu
db3e33dd8b module: fix module load for ia64
Frank reported boot regression in ia64 as:

ELILO v3.16 for EFI/IA-64
..
Uncompressing Linux... done
Loading file AC100221.initrd.img...done
[    0.000000] Linux version 6.4.0-rc3 (root@x4270) (ia64-linux-gcc
(GCC) 12.2.0, GNU ld (GNU Binutils) 2.39) #1 SMP Thu May 25 15:52:20
CEST 2023
[    0.000000] efi: EFI v1.1 by HP
[    0.000000] efi: SALsystab=0x3ee7a000 ACPI 2.0=0x3fe2a000
ESI=0x3ee7b000 SMBIOS=0x3ee7c000 HCDP=0x3fe28000
[    0.000000] PCDP: v3 at 0x3fe28000
[    0.000000] earlycon: uart8250 at MMIO 0x00000000f4050000 (options
'9600n8')
[    0.000000] printk: bootconsole [uart8250] enabled
[    0.000000] ACPI: Early table checksum verification disabled
[    0.000000] ACPI: RSDP 0x000000003FE2A000 000028 (v02 HP    )
[    0.000000] ACPI: XSDT 0x000000003FE2A02C 0000CC (v01 HP     rx2620
00000000 HP   00000000)
[...]
[    3.793350] Run /init as init process
Loading, please wait...
Starting systemd-udevd version 252.6-1
[    3.951100] ------------[ cut here ]------------
[    3.951100] WARNING: CPU: 6 PID: 140 at kernel/module/main.c:1547
__layout_sections+0x370/0x3c0
[    3.949512] Unable to handle kernel paging request at virtual address
1000000000000000
[    3.951100] Modules linked in:
[    3.951100] CPU: 6 PID: 140 Comm: (udev-worker) Not tainted 6.4.0-rc3 #1
[    3.956161] (udev-worker)[142]: Oops 11003706212352 [1]
[    3.951774] Hardware name: hp server rx2620                   , BIOS
04.29
11/30/2007
[    3.951774]
[    3.951774] Call Trace:
[    3.958339] Unable to handle kernel paging request at virtual address
1000000000000000
[    3.956161] Modules linked in:
[    3.951774]  [<a0000001000156d0>] show_stack.part.0+0x30/0x60
[    3.951774]                                 sp=e000000183a67b20
bsp=e000000183a61628
[    3.956161]
[    3.956161]

which bisect to module_memory change [1].

Debug showed that ia64 uses some special sections:

__layout_sections: section .got (sh_flags 10000002) matched to MOD_INVALID
__layout_sections: section .sdata (sh_flags 10000003) matched to MOD_INVALID
__layout_sections: section .sbss (sh_flags 10000003) matched to MOD_INVALID

All these sections are loaded to module core memory before [1].

Fix ia64 boot by loading these sections to MOD_DATA (core rw data).

[1] commit ac3b43283923 ("module: replace module_layout with module_memory")

Fixes: ac3b43283923 ("module: replace module_layout with module_memory")
Reported-by: Frank Scheiner <frank.scheiner@web.de>
Closes: https://lists.debian.org/debian-ia64/2023/05/msg00010.html
Closes: https://marc.info/?l=linux-ia64&m=168509859125505
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Song Liu <song@kernel.org>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-05-30 09:29:40 -07:00
Linus Torvalds
8b817fded4 Tracing fixes:
User events:
 
  - Use long instead of int for storing the enable set/clear bit, as it was
    found that big endian machines could end up using the wrong bits.
 
  - Split allocating mm and attaching it. This keeps the allocation separate
    from the registration and avoids various races.
 
  - Remove RCU locking around pin_user_pages_remote() as that can schedule. The
    RCU protection is no longer needed with the above split of mm allocation and
    attaching.
 
  - Rename the "link" fields of the various structs to something more
    meaningful.
 
  - Add comments around user_event_mm struct usage and locking requirements.
 
 Timerlat tracer:
 
  - Fix missed wakeup of timerlat thread caused by the timerlat interrupt
    triggering when tracing is off. The timer interrupt handler needs to always
    wake up the timerlat thread regardless if tracing is enabled or not,
    otherwise, it will never wake up.
 
 Histograms:
 
  - Fix regression of breaking the "stacktrace" modifier for variables. That
    modifier cannot be used for values, but can be used for variables that are
    passed from one histogram to the next. This was broken when adding the
    restriction to values as the variable logic used the same code.
 
  - Rename the special field "stacktrace" to "common_stacktrace". Special fields
    (that are not actually part of the event, but can act just like event
    fields, like 'comm' and 'timestamp') should be prefixed with 'common_' for
    consistency. To keep backward compatibility, 'stacktrace' can still be used
    (as with the special field 'cpu'), but can be overridden if the event has a
    field called 'stacktrace'.
 
  - Update the synthetic event selftests to use the new name (synthetic events
    are created by histograms)
 
 Tracing bootup selftests:
 
  - Reorganize the code to keep artifacts of the selftests not compiled in when
    selftests are not configured.
 
  - Add various cond_resched() around the selftest code, as the softlock
    watchdog was triggering much more often. It appears that the kernel runs
    slower now with full debugging enabled.
 
  - While debugging ftrace with ftrace (using an instance ring buffer instead of
    the top level one), I found that the selftests were disabling prints to the
    debug instance. This should not happen, as the selftests only disable
    printing to the main buffer as the selftests examine the main buffer to see
    if it has what it expects, and prints can make the tests fail. Make the
    selftests only disable printing to the toplevel buffer, and leave the
    instance buffers alone.
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Merge tag 'trace-v6.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:
 "User events:

   - Use long instead of int for storing the enable set/clear bit, as it
     was found that big endian machines could end up using the wrong
     bits.

   - Split allocating mm and attaching it. This keeps the allocation
     separate from the registration and avoids various races.

   - Remove RCU locking around pin_user_pages_remote() as that can
     schedule. The RCU protection is no longer needed with the above
     split of mm allocation and attaching.

   - Rename the "link" fields of the various structs to something more
     meaningful.

   - Add comments around user_event_mm struct usage and locking
     requirements.

  Timerlat tracer:

   - Fix missed wakeup of timerlat thread caused by the timerlat
     interrupt triggering when tracing is off. The timer interrupt
     handler needs to always wake up the timerlat thread regardless if
     tracing is enabled or not, otherwise, it will never wake up.

  Histograms:

   - Fix regression of breaking the "stacktrace" modifier for variables.
     That modifier cannot be used for values, but can be used for
     variables that are passed from one histogram to the next. This was
     broken when adding the restriction to values as the variable logic
     used the same code.

   - Rename the special field "stacktrace" to "common_stacktrace".

     Special fields (that are not actually part of the event, but can
     act just like event fields, like 'comm' and 'timestamp') should be
     prefixed with 'common_' for consistency. To keep backward
     compatibility, 'stacktrace' can still be used (as with the special
     field 'cpu'), but can be overridden if the event has a field called
     'stacktrace'.

   - Update the synthetic event selftests to use the new name (synthetic
     events are created by histograms)

  Tracing bootup selftests:

   - Reorganize the code to keep artifacts of the selftests not compiled
     in when selftests are not configured.

   - Add various cond_resched() around the selftest code, as the
     softlock watchdog was triggering much more often. It appears that
     the kernel runs slower now with full debugging enabled.

   - While debugging ftrace with ftrace (using an instance ring buffer
     instead of the top level one), I found that the selftests were
     disabling prints to the debug instance.

     This should not happen, as the selftests only disable printing to
     the main buffer as the selftests examine the main buffer to see if
     it has what it expects, and prints can make the tests fail.

     Make the selftests only disable printing to the toplevel buffer,
     and leave the instance buffers alone"

* tag 'trace-v6.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Have function_graph selftest call cond_resched()
  tracing: Only make selftest conditionals affect the global_trace
  tracing: Make tracing_selftest_running/delete nops when not used
  tracing: Have tracer selftests call cond_resched() before running
  tracing: Move setting of tracing_selftest_running out of register_tracer()
  tracing/selftests: Update synthetic event selftest to use common_stacktrace
  tracing: Rename stacktrace field to common_stacktrace
  tracing/histograms: Allow variables to have some modifiers
  tracing/user_events: Document user_event_mm one-shot list usage
  tracing/user_events: Rename link fields for clarity
  tracing/user_events: Remove RCU lock while pinning pages
  tracing/user_events: Split up mm alloc and attach
  tracing/timerlat: Always wakeup the timerlat thread
  tracing/user_events: Use long vs int for atomic bit ops
2023-05-29 07:20:13 -04:00
Linus Torvalds
ac2263b588 Revert "module: error out early on concurrent load of the same module file"
This reverts commit 9828ed3f695a138f7add89fa2a186ababceb8006.

Sadly, it does seem to cause failures to load modules. Johan Hovold reports:

 "This change breaks module loading during boot on the Lenovo Thinkpad
  X13s (aarch64).

  Specifically it results in indefinite probe deferral of the display
  and USB (ethernet) which makes it a pain to debug. Typing in the dark
  to acquire some logs reveals that other modules are missing as well"

Since this was applied late as a "let's try this", I'm reverting it
asap, and we can try to figure out what goes wrong later.  The excessive
parallel module loading problem is annoying, but not noticeable in
normal situations, and this was only meant as an optimistic workaround
for a user-space bug.

One possible solution may be to do the optimistic exclusive open first,
and then use a lock to serialize loading if that fails.

Reported-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/lkml/ZHRpH-JXAxA6DnzR@hovoldconsulting.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-05-29 06:40:33 -04:00