37788 Commits

Author SHA1 Message Date
Gavrilov Ilia
90962b3b1c relay: fix type mismatch when allocating memory in relay_create_buf()
[ Upstream commit 4d8586e04602fe42f0a782d2005956f8b6302678 ]

The 'padding' field of the 'rchan_buf' structure is an array of 'size_t'
elements, but the memory is allocated for an array of 'size_t *' elements.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Link: https://lkml.kernel.org/r/20221129092002.3538384-1-Ilia.Gavrilov@infotecs.ru
Fixes: b86ff981a825 ("[PATCH] relay: migrate from relayfs to a generic relay API")
Signed-off-by: Ilia.Gavrilov <Ilia.Gavrilov@infotecs.ru>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: wuchi <wuchi.zero@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:05 +01:00
Vincent Donnefort
b73c76c3c4 cpu/hotplug: Do not bail-out in DYING/STARTING sections
[ Upstream commit 6f855b39e4602b6b42a8e5cbcfefb8a1b8b5f0be ]

The DYING/STARTING callbacks are not expected to fail. However, as reported
by Derek, buggy drivers such as tboot are still free to return errors
within those sections, which halts the hot(un)plug and leaves the CPU in an
unrecoverable state.

As there is no rollback possible, only log the failures and proceed with
the following steps.

This restores the hotplug behaviour prior to commit 453e41085183
("cpu/hotplug: Add cpuhp_invoke_callback_range()")

Fixes: 453e41085183 ("cpu/hotplug: Add cpuhp_invoke_callback_range()")
Reported-by: Derek Dolney <z23@posteo.net>
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Derek Dolney <z23@posteo.net>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215867
Link: https://lore.kernel.org/r/20220927101259.1149636-1-vdonnefort@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:04 +01:00
Phil Auld
6eb1802184 cpu/hotplug: Make target_store() a nop when target == state
[ Upstream commit 64ea6e44f85b9b75925ebe1ba0e6e8430cc4e06f ]

Writing the current state back in hotplug/target calls cpu_down()
which will set cpu dying even when it isn't and then nothing will
ever clear it. A stress test that reads values and writes them back
for all cpu device files in sysfs will trigger the BUG() in
select_fallback_rq once all cpus are marked as dying.

kernel/cpu.c::target_store()
	...
        if (st->state < target)
                ret = cpu_up(dev->id, target);
        else
                ret = cpu_down(dev->id, target);

cpu_down() -> cpu_set_state()
	 bool bringup = st->state < target;
	 ...
	 if (cpu_dying(cpu) != !bringup)
		set_cpu_dying(cpu, !bringup);

Fix this by letting state==target fall through in the target_store()
conditional. Also make sure st->target == target in that case.

Fixes: 757c989b9994 ("cpu/hotplug: Make target state writeable")
Signed-off-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lore.kernel.org/r/20221117162329.3164999-2-pauld@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:04 +01:00
Alexey Izbyshev
cd130e2676 futex: Resend potentially swallowed owner death notification
[ Upstream commit 90d758896787048fa3d4209309d4800f3920e66f ]

Commit ca16d5bee598 ("futex: Prevent robust futex exit race") addressed
two cases when tasks waiting on a robust non-PI futex remained blocked
despite the futex not being owned anymore:

* if the owner died after writing zero to the futex word, but before
  waking up a waiter

* if a task waiting on the futex was woken up, but died before updating
  the futex word (effectively swallowing the notification without acting
  on it)

In the second case, the task could be woken up either by the previous
owner (after the futex word was reset to zero) or by the kernel (after
the OWNER_DIED bit was set and the TID part of the futex word was reset
to zero) if the previous owner died without the resetting the futex.

Because the referenced commit wakes up a potential waiter only if the
whole futex word is zero, the latter subcase remains unaddressed.

Fix this by looking only at the TID part of the futex when deciding
whether a wake up is needed.

Fixes: ca16d5bee598 ("futex: Prevent robust futex exit race")
Signed-off-by: Alexey Izbyshev <izbyshev@ispras.ru>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221111215439.248185-1-izbyshev@ispras.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:04 +01:00
Peter Zijlstra
fd8a10d44c futex: Move to kernel/futex/
[ Upstream commit 77e52ae35463521041906c510fe580d15663bb93 ]

In preparation for splitup..

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: André Almeida <andrealmeid@collabora.com>
Link: https://lore.kernel.org/r/20210923171111.300673-2-andrealmeid@collabora.com
Stable-dep-of: 90d758896787 ("futex: Resend potentially swallowed owner death notification")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:04 +01:00
Yang Yingliang
93e3c80338 genirq/irqdesc: Don't try to remove non-existing sysfs files
[ Upstream commit 9049e1ca41983ab773d7ea244bee86d7835ec9f5 ]

Fault injection tests trigger warnings like this:

  kernfs: can not remove 'chip_name', no directory
  WARNING: CPU: 0 PID: 253 at fs/kernfs/dir.c:1616 kernfs_remove_by_name_ns+0xce/0xe0
  RIP: 0010:kernfs_remove_by_name_ns+0xce/0xe0
  Call Trace:
   <TASK>
   remove_files.isra.1+0x3f/0xb0
   sysfs_remove_group+0x68/0xe0
   sysfs_remove_groups+0x41/0x70
   __kobject_del+0x45/0xc0
   kobject_del+0x29/0x40
   free_desc+0x42/0x70
   irq_free_descs+0x5e/0x90

The reason is that the interrupt descriptor sysfs handling does not roll
back on a failing kobject_add() during allocation. If the descriptor is
freed later on, kobject_del() is invoked with a not added kobject resulting
in the above warnings.

A proper rollback in case of a kobject_add() failure would be the straight
forward solution. But this is not possible due to the way how interrupt
descriptor sysfs handling works.

Interrupt descriptors are allocated before sysfs becomes available. So the
sysfs files for the early allocated descriptors are added later in the boot
process. At this point there can be nothing useful done about a failing
kobject_add(). For consistency the interrupt descriptor allocation always
treats kobject_add() failures as non-critical and just emits a warning.

To solve this problem, keep track in the interrupt descriptor whether
kobject_add() was successful or not and make the invocation of
kobject_del() conditional on that.

[ tglx: Massage changelog, comments and use a state bit. ]

Fixes: ecb3f394c5db ("genirq: Expose interrupt information through sysfs")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20221128151612.1786122-1-yangyingliang@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:03 +01:00
Chen Zhongjin
f790dfe816 perf: Fix possible memleak in pmu_dev_alloc()
[ Upstream commit e8d7a90c08ce963c592fb49845f2ccc606a2ac21 ]

In pmu_dev_alloc(), when dev_set_name() failed, it will goto free_dev
and call put_device(pmu->dev) to release it.
However pmu->dev->release is assigned after this, which makes warning
and memleak.
Call dev_set_name() after pmu->dev->release = pmu_dev_release to fix it.

  Device '(null)' does not have a release() function...
  WARNING: CPU: 2 PID: 441 at drivers/base/core.c:2332 device_release+0x1b9/0x240
  ...
  Call Trace:
    <TASK>
    kobject_put+0x17f/0x460
    put_device+0x20/0x30
    pmu_dev_alloc+0x152/0x400
    perf_pmu_register+0x96b/0xee0
    ...
  kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
  unreferenced object 0xffff888014759000 (size 2048):
    comm "modprobe", pid 441, jiffies 4294931444 (age 38.332s)
    backtrace:
      [<0000000005aed3b4>] kmalloc_trace+0x27/0x110
      [<000000006b38f9b8>] pmu_dev_alloc+0x50/0x400
      [<00000000735f17be>] perf_pmu_register+0x96b/0xee0
      [<00000000e38477f1>] 0xffffffffc0ad8603
      [<000000004e162216>] do_one_initcall+0xd0/0x4e0
      ...

Fixes: abe43400579d ("perf: Sysfs enumeration")
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221111103653.91058-1-chenzhongjin@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:01 +01:00
xiongxin
e4d0d13b46 PM: hibernate: Fix mistake in kerneldoc comment
[ Upstream commit 6e5d7300cbe7c3541bc31f16db3e9266e6027b4b ]

The actual maximum image size formula in hibernate_preallocate_memory()
is as follows:

max_size = (count - (size + PAGES_FOR_IO)) / 2
	    - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE);

but the one in the kerneldoc comment of the function is different and
incorrect.

Fixes: ddeb64870810 ("PM / Hibernate: Add sysfs knob to control size of memory for drivers")
Signed-off-by: xiongxin <xiongxin@kylinos.cn>
[ rjw: Subject and changelog rewrite ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:01 +01:00
Qais Yousef
3af4f5cb8a sched/uclamp: Make asym_fits_capacity() use util_fits_cpu()
[ Upstream commit a2e7f03ed28fce26c78b985f87913b6ce3accf9d ]

Use the new util_fits_cpu() to ensure migration margin and capacity
pressure are taken into account correctly when uclamp is being used
otherwise we will fail to consider CPUs as fitting in scenarios where
they should.

s/asym_fits_capacity/asym_fits_cpu/ to better reflect what it does now.

Fixes: b4c9c9f15649 ("sched/fair: Prefer prev cpu in asymmetric wakeup path")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220804143609.515789-6-qais.yousef@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:01 +01:00
Dietmar Eggemann
23cb580e0c sched/core: Introduce sched_asym_cpucap_active()
[ Upstream commit 740cf8a760b73e8375bfb4bedcbe9746183350f9 ]

Create an inline helper for conditional code to be only executed on
asymmetric CPU capacity systems. This makes these (currently ~10 and
future) conditions a lot more readable.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20220729111305.1275158-2-dietmar.eggemann@arm.com
Stable-dep-of: a2e7f03ed28f ("sched/uclamp: Make asym_fits_capacity() use util_fits_cpu()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:01 +01:00
Vincent Guittot
41c2dba388 sched/fair: Removed useless update of p->recent_used_cpu
[ Upstream commit a7ba894821b6ade7bb420455f87020b2838d6180 ]

Since commit 89aafd67f28c ("sched/fair: Use prev instead of new target as recent_used_cpu"),
p->recent_used_cpu is unconditionnaly set with prev.

Fixes: 89aafd67f28c ("sched/fair: Use prev instead of new target as recent_used_cpu")
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Link: https://lkml.kernel.org/r/20210928103544.27489-1-vincent.guittot@linaro.org
Stable-dep-of: a2e7f03ed28f ("sched/uclamp: Make asym_fits_capacity() use util_fits_cpu()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:01 +01:00
Qais Yousef
55ffeab089 sched/uclamp: Make select_idle_capacity() use util_fits_cpu()
[ Upstream commit b759caa1d9f667b94727b2ad12589cbc4ce13a82 ]

Use the new util_fits_cpu() to ensure migration margin and capacity
pressure are taken into account correctly when uclamp is being used
otherwise we will fail to consider CPUs as fitting in scenarios where
they should.

Fixes: b4c9c9f15649 ("sched/fair: Prefer prev cpu in asymmetric wakeup path")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220804143609.515789-5-qais.yousef@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:01 +01:00
Qais Yousef
4639bfbb83 sched/uclamp: Make task_fits_capacity() use util_fits_cpu()
[ Upstream commit b48e16a69792b5dc4a09d6807369d11b2970cc36 ]

So that the new uclamp rules in regard to migration margin and capacity
pressure are taken into account correctly.

Fixes: a7008c07a568 ("sched/fair: Make task_fits_capacity() consider uclamp restrictions")
Co-developed-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220804143609.515789-3-qais.yousef@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:00 +01:00
Qais Yousef
309e50cbfe sched/uclamp: Fix relationship between uclamp and migration margin
[ Upstream commit 48d5e9daa8b767e75ed9421665b037a49ce4bc04 ]

fits_capacity() verifies that a util is within 20% margin of the
capacity of a CPU, which is an attempt to speed up upmigration.

But when uclamp is used, this 20% margin is problematic because for
example if a task is boosted to 1024, then it will not fit on any CPU
according to fits_capacity() logic.

Or if a task is boosted to capacity_orig_of(medium_cpu). The task will
end up on big instead on the desired medium CPU.

Similar corner cases exist for uclamp and usage of capacity_of().
Slightest irq pressure on biggest CPU for example will make a 1024
boosted task look like it can't fit.

What we really want is for uclamp comparisons to ignore the migration
margin and capacity pressure, yet retain them for when checking the
_actual_ util signal.

For example, task p:

	p->util_avg = 300
	p->uclamp[UCLAMP_MIN] = 1024

Will fit a big CPU. But

	p->util_avg = 900
	p->uclamp[UCLAMP_MIN] = 1024

will not, this should trigger overutilized state because the big CPU is
now *actually* being saturated.

Similar reasoning applies to capping tasks with UCLAMP_MAX. For example:

	p->util_avg = 1024
	p->uclamp[UCLAMP_MAX] = capacity_orig_of(medium_cpu)

Should fit the task on medium cpus without triggering overutilized
state.

Inlined comments expand more on desired behavior in more scenarios.

Introduce new util_fits_cpu() function which encapsulates the new logic.
The new function is not used anywhere yet, but will be used to update
various users of fits_capacity() in later patches.

Fixes: af24bde8df202 ("sched/uclamp: Add uclamp support to energy_compute()")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220804143609.515789-2-qais.yousef@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:00 +01:00
Vincent Donnefort
54a766e196 sched/fair: Cleanup task_util and capacity type
[ Upstream commit ef8df9798d469b7c45c66664550e93469749f1e8 ]

task_util and capacity are comparable unsigned long values. There is no
need for an intermidiate implicit signed cast.

Signed-off-by: Vincent Donnefort <vincent.donnefort@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211207095755.859972-1-vincent.donnefort@arm.com
Stable-dep-of: 48d5e9daa8b7 ("sched/uclamp: Fix relationship between uclamp and migration margin")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:00 +01:00
Kuniyuki Iwashima
a31a647a3d seccomp: Move copy_seccomp() to no failure path.
[ Upstream commit a1140cb215fa13dcec06d12ba0c3ee105633b7c4 ]

Our syzbot instance reported memory leaks in do_seccomp() [0], similar
to the report [1].  It shows that we miss freeing struct seccomp_filter
and some objects included in it.

We can reproduce the issue with the program below [2] which calls one
seccomp() and two clone() syscalls.

The first clone()d child exits earlier than its parent and sends a
signal to kill it during the second clone(), more precisely before the
fatal_signal_pending() test in copy_process().  When the parent receives
the signal, it has to destroy the embryonic process and return -EINTR to
user space.  In the failure path, we have to call seccomp_filter_release()
to decrement the filter's refcount.

Initially, we called it in free_task() called from the failure path, but
the commit 3a15fb6ed92c ("seccomp: release filter after task is fully
dead") moved it to release_task() to notify user space as early as possible
that the filter is no longer used.

To keep the change and current seccomp refcount semantics, let's move
copy_seccomp() just after the signal check and add a WARN_ON_ONCE() in
free_task() for future debugging.

[0]:
unreferenced object 0xffff8880063add00 (size 256):
  comm "repro_seccomp", pid 230, jiffies 4294687090 (age 9.914s)
  hex dump (first 32 bytes):
    01 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00  ................
    ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
  backtrace:
    do_seccomp (./include/linux/slab.h:600 ./include/linux/slab.h:733 kernel/seccomp.c:666 kernel/seccomp.c:708 kernel/seccomp.c:1871 kernel/seccomp.c:1991)
    do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
    entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
unreferenced object 0xffffc90000035000 (size 4096):
  comm "repro_seccomp", pid 230, jiffies 4294687090 (age 9.915s)
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 00 00 00 00 05 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    __vmalloc_node_range (mm/vmalloc.c:3226)
    __vmalloc_node (mm/vmalloc.c:3261 (discriminator 4))
    bpf_prog_alloc_no_stats (kernel/bpf/core.c:91)
    bpf_prog_alloc (kernel/bpf/core.c:129)
    bpf_prog_create_from_user (net/core/filter.c:1414)
    do_seccomp (kernel/seccomp.c:671 kernel/seccomp.c:708 kernel/seccomp.c:1871 kernel/seccomp.c:1991)
    do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
    entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
unreferenced object 0xffff888003fa1000 (size 1024):
  comm "repro_seccomp", pid 230, jiffies 4294687090 (age 9.915s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    bpf_prog_alloc_no_stats (./include/linux/slab.h:600 ./include/linux/slab.h:733 kernel/bpf/core.c:95)
    bpf_prog_alloc (kernel/bpf/core.c:129)
    bpf_prog_create_from_user (net/core/filter.c:1414)
    do_seccomp (kernel/seccomp.c:671 kernel/seccomp.c:708 kernel/seccomp.c:1871 kernel/seccomp.c:1991)
    do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
    entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
unreferenced object 0xffff888006360240 (size 16):
  comm "repro_seccomp", pid 230, jiffies 4294687090 (age 9.915s)
  hex dump (first 16 bytes):
    01 00 37 00 76 65 72 6c e0 83 01 06 80 88 ff ff  ..7.verl........
  backtrace:
    bpf_prog_store_orig_filter (net/core/filter.c:1137)
    bpf_prog_create_from_user (net/core/filter.c:1428)
    do_seccomp (kernel/seccomp.c:671 kernel/seccomp.c:708 kernel/seccomp.c:1871 kernel/seccomp.c:1991)
    do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
    entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
unreferenced object 0xffff8880060183e0 (size 8):
  comm "repro_seccomp", pid 230, jiffies 4294687090 (age 9.915s)
  hex dump (first 8 bytes):
    06 00 00 00 00 00 ff 7f                          ........
  backtrace:
    kmemdup (mm/util.c:129)
    bpf_prog_store_orig_filter (net/core/filter.c:1144)
    bpf_prog_create_from_user (net/core/filter.c:1428)
    do_seccomp (kernel/seccomp.c:671 kernel/seccomp.c:708 kernel/seccomp.c:1871 kernel/seccomp.c:1991)
    do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
    entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

[1]: https://syzkaller.appspot.com/bug?id=2809bb0ac77ad9aa3f4afe42d6a610aba594a987

[2]:

void main(void)
{
	struct sock_filter filter[] = {
		BPF_STMT(BPF_RET | BPF_K, SECCOMP_RET_ALLOW),
	};
	struct sock_fprog fprog = {
		.len = sizeof(filter) / sizeof(filter[0]),
		.filter = filter,
	};
	long i, pid;

	syscall(__NR_seccomp, SECCOMP_SET_MODE_FILTER, 0, &fprog);

	for (i = 0; i < 2; i++) {
		pid = syscall(__NR_clone, CLONE_NEWNET | SIGKILL, NULL, NULL, 0);
		if (pid == 0)
			return;
	}
}

Fixes: 3a15fb6ed92c ("seccomp: release filter after task is fully dead")
Reported-by: syzbot+ab17848fe269b573eb71@syzkaller.appspotmail.com
Reported-by: Ayushman Dutta <ayudutta@amazon.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220823154532.82913-1-kuniyu@amazon.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:00 +01:00
Peter Zijlstra
8bffa95ac1 perf: Fix perf_pending_task() UaF
[ Upstream commit 517e6a301f34613bff24a8e35b5455884f2d83d8 ]

Per syzbot it is possible for perf_pending_task() to run after the
event is free()'d. There are two related but distinct cases:

 - the task_work was already queued before destroying the event;
 - destroying the event itself queues the task_work.

The first cannot be solved using task_work_cancel() since
perf_release() itself might be called from a task_work (____fput),
which means the current->task_works list is already empty and
task_work_cancel() won't be able to find the perf_pending_task()
entry.

The simplest alternative is extending the perf_event lifetime to cover
the task_work.

The second is just silly, queueing a task_work while you know the
event is going away makes no sense and is easily avoided by
re-arranging how the event is marked STATE_DEAD and ensuring it goes
through STATE_OFF on the way down.

Reported-by: syzbot+9228d6098455bb209ec8@syzkaller.appspotmail.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Marco Elver <elver@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-19 12:36:43 +01:00
Jens Axboe
f435c66d23 io_uring: move to separate directory
[ Upstream commit ed29b0b4fd835b058ddd151c49d021e28d631ee6 ]

In preparation for splitting io_uring up a bit, move it into its own
top level directory. It didn't really belong in fs/ anyway, as it's
not a file system only API.

This adds io_uring/ and moves the core files in there, and updates the
MAINTAINERS file for the new location.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 998b30c3948e ("io_uring: Fix a null-ptr-deref in io_tctx_exit_cb()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-14 11:37:31 +01:00
Tejun Heo
aad8bbd17a memcg: fix possible use-after-free in memcg_write_event_control()
commit 4a7ba45b1a435e7097ca0f79a847d0949d0eb088 upstream.

memcg_write_event_control() accesses the dentry->d_name of the specified
control fd to route the write call.  As a cgroup interface file can't be
renamed, it's safe to access d_name as long as the specified file is a
regular cgroup file.  Also, as these cgroup interface files can't be
removed before the directory, it's safe to access the parent too.

Prior to 347c4a874710 ("memcg: remove cgroup_event->cft"), there was a
call to __file_cft() which verified that the specified file is a regular
cgroupfs file before further accesses.  The cftype pointer returned from
__file_cft() was no longer necessary and the commit inadvertently dropped
the file type check with it allowing any file to slip through.  With the
invarients broken, the d_name and parent accesses can now race against
renames and removals of arbitrary files and cause use-after-free's.

Fix the bug by resurrecting the file type check in __file_cft().  Now that
cgroupfs is implemented through kernfs, checking the file operations needs
to go through a layer of indirection.  Instead, let's check the superblock
and dentry type.

Link: https://lkml.kernel.org/r/Y5FRm/cfcKPGzWwl@slm.duckdns.org
Fixes: 347c4a874710 ("memcg: remove cgroup_event->cft")
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Jann Horn <jannh@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>	[3.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-14 11:37:19 +01:00
Linus Torvalds
48642f9431 proc: proc_skip_spaces() shouldn't think it is working on C strings
commit bce9332220bd677d83b19d21502776ad555a0e73 upstream.

proc_skip_spaces() seems to think it is working on C strings, and ends
up being just a wrapper around skip_spaces() with a really odd calling
convention.

Instead of basing it on skip_spaces(), it should have looked more like
proc_skip_char(), which really is the exact same function (except it
skips a particular character, rather than whitespace).  So use that as
inspiration, odd coding and all.

Now the calling convention actually makes sense and works for the
intended purpose.

Reported-and-tested-by: Kyle Zeng <zengyhkyle@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:28:45 +01:00
Linus Torvalds
3eb9213f66 proc: avoid integer type confusion in get_proc_long
commit e6cfaf34be9fcd1a8285a294e18986bfc41a409c upstream.

proc_get_long() is passed a size_t, but then assigns it to an 'int'
variable for the length.  Let's not do that, even if our IO paths are
limited to MAX_RW_COUNT (exactly because of these kinds of type errors).

So do the proper test in the rigth type.

Reported-by: Kyle Zeng <zengyhkyle@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:28:45 +01:00
Steven Rostedt (Google)
417d5ea6e7 tracing: Free buffers when a used dynamic event is removed
commit 4313e5a613049dfc1819a6dfb5f94cf2caff9452 upstream.

After 65536 dynamic events have been added and removed, the "type" field
of the event then uses the first type number that is available (not
currently used by other events). A type number is the identifier of the
binary blobs in the tracing ring buffer (known as events) to map them to
logic that can parse the binary blob.

The issue is that if a dynamic event (like a kprobe event) is traced and
is in the ring buffer, and then that event is removed (because it is
dynamic, which means it can be created and destroyed), if another dynamic
event is created that has the same number that new event's logic on
parsing the binary blob will be used.

To show how this can be an issue, the following can crash the kernel:

 # cd /sys/kernel/tracing
 # for i in `seq 65536`; do
     echo 'p:kprobes/foo do_sys_openat2 $arg1:u32' > kprobe_events
 # done

For every iteration of the above, the writing to the kprobe_events will
remove the old event and create a new one (with the same format) and
increase the type number to the next available on until the type number
reaches over 65535 which is the max number for the 16 bit type. After it
reaches that number, the logic to allocate a new number simply looks for
the next available number. When an dynamic event is removed, that number
is then available to be reused by the next dynamic event created. That is,
once the above reaches the max number, the number assigned to the event in
that loop will remain the same.

Now that means deleting one dynamic event and created another will reuse
the previous events type number. This is where bad things can happen.
After the above loop finishes, the kprobes/foo event which reads the
do_sys_openat2 function call's first parameter as an integer.

 # echo 1 > kprobes/foo/enable
 # cat /etc/passwd > /dev/null
 # cat trace
             cat-2211    [005] ....  2007.849603: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196
             cat-2211    [005] ....  2007.849620: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196
             cat-2211    [005] ....  2007.849838: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196
             cat-2211    [005] ....  2007.849880: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196
 # echo 0 > kprobes/foo/enable

Now if we delete the kprobe and create a new one that reads a string:

 # echo 'p:kprobes/foo do_sys_openat2 +0($arg2):string' > kprobe_events

And now we can the trace:

 # cat trace
        sendmail-1942    [002] .....   530.136320: foo: (do_sys_openat2+0x0/0x240) arg1=             cat-2046    [004] .....   530.930817: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������"
             cat-2046    [004] .....   530.930961: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������"
             cat-2046    [004] .....   530.934278: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������"
             cat-2046    [004] .....   530.934563: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������"
            bash-1515    [007] .....   534.299093: foo: (do_sys_openat2+0x0/0x240) arg1="kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk���������@��4Z����;Y�����U

And dmesg has:

==================================================================
BUG: KASAN: use-after-free in string+0xd4/0x1c0
Read of size 1 at addr ffff88805fdbbfa0 by task cat/2049

 CPU: 0 PID: 2049 Comm: cat Not tainted 6.1.0-rc6-test+ #641
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
 Call Trace:
  <TASK>
  dump_stack_lvl+0x5b/0x77
  print_report+0x17f/0x47b
  kasan_report+0xad/0x130
  string+0xd4/0x1c0
  vsnprintf+0x500/0x840
  seq_buf_vprintf+0x62/0xc0
  trace_seq_printf+0x10e/0x1e0
  print_type_string+0x90/0xa0
  print_kprobe_event+0x16b/0x290
  print_trace_line+0x451/0x8e0
  s_show+0x72/0x1f0
  seq_read_iter+0x58e/0x750
  seq_read+0x115/0x160
  vfs_read+0x11d/0x460
  ksys_read+0xa9/0x130
  do_syscall_64+0x3a/0x90
  entry_SYSCALL_64_after_hwframe+0x63/0xcd
 RIP: 0033:0x7fc2e972ade2
 Code: c0 e9 b2 fe ff ff 50 48 8d 3d b2 3f 0a 00 e8 05 f0 01 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24
 RSP: 002b:00007ffc64e687c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
 RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2e972ade2
 RDX: 0000000000020000 RSI: 00007fc2e980d000 RDI: 0000000000000003
 RBP: 00007fc2e980d000 R08: 00007fc2e980c010 R09: 0000000000000000
 R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000020f00
 R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
  </TASK>

 The buggy address belongs to the physical page:
 page:ffffea00017f6ec0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5fdbb
 flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff)
 raw: 000fffffc0000000 0000000000000000 ffffea00017f6ec8 0000000000000000
 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff88805fdbbe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff88805fdbbf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 >ffff88805fdbbf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                ^
  ffff88805fdbc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff88805fdbc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ==================================================================

This was found when Zheng Yejian sent a patch to convert the event type
number assignment to use IDA, which gives the next available number, and
this bug showed up in the fuzz testing by Yujie Liu and the kernel test
robot. But after further analysis, I found that this behavior is the same
as when the event type numbers go past the 16bit max (and the above shows
that).

As modules have a similar issue, but is dealt with by setting a
"WAS_ENABLED" flag when a module event is enabled, and when the module is
freed, if any of its events were enabled, the ring buffer that holds that
event is also cleared, to prevent reading stale events. The same can be
done for dynamic events.

If any dynamic event that is being removed was enabled, then make sure the
buffers they were enabled in are now cleared.

Link: https://lkml.kernel.org/r/20221123171434.545706e3@gandalf.local.home
Link: https://lore.kernel.org/all/20221110020319.1259291-1-zhengyejian1@huawei.com/

Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Depends-on: e18eb8783ec49 ("tracing: Add tracing_reset_all_online_cpus_unlocked() function")
Depends-on: 5448d44c38557 ("tracing: Add unified dynamic event framework")
Depends-on: 6212dd29683ee ("tracing/kprobes: Use dyn_event framework for kprobe events")
Depends-on: 065e63f951432 ("tracing: Only have rmmod clear buffers that its events were active in")
Depends-on: 575380da8b469 ("tracing: Only clear trace buffer on module unload if event was traced")
Fixes: 77b44d1b7c283 ("tracing/kprobes: Rename Kprobe-tracer to kprobe-event")
Reported-by: Zheng Yejian <zhengyejian1@huawei.com>
Reported-by: Yujie Liu <yujie.liu@intel.com>
Reported-by: kernel test robot <yujie.liu@intel.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:28:43 +01:00
Steven Rostedt (Google)
52fc245d15 tracing: Fix race where histograms can be called before the event
commit ef38c79a522b660f7f71d45dad2d6244bc741841 upstream.

commit 94eedf3dded5 ("tracing: Fix race where eprobes can be called before
the event") fixed an issue where if an event is soft disabled, and the
trigger is being added, there's a small window where the event sees that
there's a trigger but does not see that it requires reading the event yet,
and then calls the trigger with the record == NULL.

This could be solved with adding memory barriers in the hot path, or to
make sure that all the triggers requiring a record check for NULL. The
latter was chosen.

Commit 94eedf3dded5 set the eprobe trigger handle to check for NULL, but
the same needs to be done with histograms.

Link: https://lore.kernel.org/linux-trace-kernel/20221118211809.701d40c0f8a757b0df3c025a@kernel.org/
Link: https://lore.kernel.org/linux-trace-kernel/20221123164323.03450c3a@gandalf.local.home

Cc: Tom Zanussi <zanussi@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 7491e2c442781 ("tracing: Add a probe that attaches to trace events")
Reported-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:28:43 +01:00
Daniel Bristot de Oliveira
cb2b0612cd tracing/osnoise: Fix duration type
commit 022632f6c43a86f2135642dccd5686de318e861d upstream.

The duration type is a 64 long value, not an int. This was
causing some long noise to report wrong values.

Change the duration to a 64 bits value.

Link: https://lkml.kernel.org/r/a93d8a8378c7973e9c609de05826533c9e977939.1668692096.git.bristot@kernel.org

Cc: stable@vger.kernel.org
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Fixes: bce29ac9ce0b ("trace: Add osnoise tracer")
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:28:43 +01:00
Xu Kuohai
e376183167 bpf: Do not copy spin lock field from user in bpf_selem_alloc
[ Upstream commit 836e49e103dfeeff670c934b7d563cbd982fce87 ]

bpf_selem_alloc function is used by inode_storage, sk_storage and
task_storage maps to set map value, for these map types, there may
be a spin lock in the map value, so if we use memcpy to copy the whole
map value from user, the spin lock field may be initialized incorrectly.

Since the spin lock field is zeroed by kzalloc, call copy_map_value
instead of memcpy to skip copying the spin lock field to fix it.

Fixes: 6ac99e8f23d4 ("bpf: Introduce bpf sk local storage")
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20221114134720.1057939-2-xukuohai@huawei.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-08 11:28:39 +01:00
Hou Tao
ee3d37d796 bpf, perf: Use subprog name when reporting subprog ksymbol
[ Upstream commit 47df8a2f78bc34ff170d147d05b121f84e252b85 ]

Since commit bfea9a8574f3 ("bpf: Add name to struct bpf_ksym"), when
reporting subprog ksymbol to perf, prog name instead of subprog name is
used. The backtrace of bpf program with subprogs will be incorrect as
shown below:

  ffffffffc02deace bpf_prog_e44a3057dcb151f8_overwrite+0x66
  ffffffffc02de9f7 bpf_prog_e44a3057dcb151f8_overwrite+0x9f
  ffffffffa71d8d4e trace_call_bpf+0xce
  ffffffffa71c2938 perf_call_bpf_enter.isra.0+0x48

overwrite is the entry program and it invokes the overwrite_htab subprog
through bpf_loop, but in above backtrace, overwrite program just jumps
inside itself.

Fixing it by using subprog name when reporting subprog ksymbol. After
the fix, the output of perf script will be correct as shown below:

  ffffffffc031aad2 bpf_prog_37c0bec7d7c764a4_overwrite_htab+0x66
  ffffffffc031a9e7 bpf_prog_c7eb827ef4f23e71_overwrite+0x9f
  ffffffffa3dd8d4e trace_call_bpf+0xce
  ffffffffa3dc2938 perf_call_bpf_enter.isra.0+0x48

Fixes: bfea9a8574f3 ("bpf: Add name to struct bpf_ksym")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20221114095733.158588-1-houtao@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-08 11:28:38 +01:00
Luiz Capitulino
7d0c25b5fe genirq: Take the proposed affinity at face value if force==true
From: Marc Zyngier <maz@kernel.org>

commit c48c8b829d2b966a6649827426bcdba082ccf922 upstream.

Although setting the affinity of an interrupt to a set of CPUs that doesn't
have any online CPU is generally frowned apon, there are a few limited
cases where such affinity is set from a CPUHP notifier, setting the
affinity to a CPU that isn't online yet.

The saving grace is that this is always done using the 'force' attribute,
which gives a hint that the affinity setting can be outside of the online
CPU mask and the callsite set this flag with the knowledge that the
underlying interrupt controller knows to handle it.

This restores the expected behaviour on Marek's system.

Fixes: 33de0aa4bae9 ("genirq: Always limit the affinity to online CPUs")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/4b7fc13c-887b-a664-26e8-45aed13f048a@samsung.com
Link: https://lore.kernel.org/r/20220414140011.541725-1-maz@kernel.org

Signed-off-by: Luiz Capitulino <luizcap@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-02 17:41:12 +01:00
Luiz Capitulino
52a93f2dcf genirq: Always limit the affinity to online CPUs
From: Marc Zyngier <maz@kernel.org>

commit 33de0aa4bae982ed6f7c777f86b5af3e627ac937 upstream.

[ Fixed small conflicts due to the HK_FLAG_MANAGED_IRQ flag been
  renamed on upstream ]

When booting with maxcpus=<small number> (or even loading a driver
while most CPUs are offline), it is pretty easy to observe managed
affinities containing a mix of online and offline CPUs being passed
to the irqchip driver.

This means that the irqchip cannot trust the affinity passed down
from the core code, which is a bit annoying and requires (at least
in theory) all drivers to implement some sort of affinity narrowing.

In order to address this, always limit the cpumask to the set of
online CPUs.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220405185040.206297-3-maz@kernel.org

Signed-off-by: Luiz Capitulino <luizcap@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-02 17:41:11 +01:00
Luiz Capitulino
599cf4b845 genirq/msi: Shutdown managed interrupts with unsatifiable affinities
From: Marc Zyngier <maz@kernel.org>

commit d802057c7c553ad426520a053da9f9fe08e2c35a upstream.

[ This commit is almost a rewrite because it conflicts with Thomas
  Gleixner's refactoring of this code in v5.17-rc1. I wasn't sure if
  I should drop all the s-o-bs (including Mark's), but decided
  to keep as the original commit ]

When booting with maxcpus=<small number>, interrupt controllers
such as the GICv3 ITS may not be able to satisfy the affinity of
some managed interrupts, as some of the HW resources are simply
not available.

The same thing happens when loading a driver using managed interrupts
while CPUs are offline.

In order to deal with this, do not try to activate such interrupt
if there is no online CPU capable of handling it. Instead, place
it in shutdown state. Once a capable CPU shows up, it will be
activated.

Reported-by: John Garry <john.garry@huawei.com>
Reported-by: David Decotigny <ddecotig@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/20220405185040.206297-2-maz@kernel.org

Signed-off-by: Luiz Capitulino <luizcap@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-02 17:41:11 +01:00
Mukesh Ojha
feb2eda5e1 gcov: clang: fix the buffer overflow issue
commit a6f810efabfd789d3bbafeacb4502958ec56c5ce upstream.

Currently, in clang version of gcov code when module is getting removed
gcov_info_add() incorrectly adds the sfn_ptr->counter to all the
dst->functions and it result in the kernel panic in below crash report.
Fix this by properly handling it.

[    8.899094][  T599] Unable to handle kernel write to read-only memory at virtual address ffffff80461cc000
[    8.899100][  T599] Mem abort info:
[    8.899102][  T599]   ESR = 0x9600004f
[    8.899103][  T599]   EC = 0x25: DABT (current EL), IL = 32 bits
[    8.899105][  T599]   SET = 0, FnV = 0
[    8.899107][  T599]   EA = 0, S1PTW = 0
[    8.899108][  T599]   FSC = 0x0f: level 3 permission fault
[    8.899110][  T599] Data abort info:
[    8.899111][  T599]   ISV = 0, ISS = 0x0000004f
[    8.899113][  T599]   CM = 0, WnR = 1
[    8.899114][  T599] swapper pgtable: 4k pages, 39-bit VAs, pgdp=00000000ab8de000
[    8.899116][  T599] [ffffff80461cc000] pgd=18000009ffcde003, p4d=18000009ffcde003, pud=18000009ffcde003, pmd=18000009ffcad003, pte=00600000c61cc787
[    8.899124][  T599] Internal error: Oops: 9600004f [#1] PREEMPT SMP
[    8.899265][  T599] Skip md ftrace buffer dump for: 0x1609e0
....
..,
[    8.899544][  T599] CPU: 7 PID: 599 Comm: modprobe Tainted: G S         OE     5.15.41-android13-8-g38e9b1af6bce #1
[    8.899547][  T599] Hardware name: XXX (DT)
[    8.899549][  T599] pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
[    8.899551][  T599] pc : gcov_info_add+0x9c/0xb8
[    8.899557][  T599] lr : gcov_event+0x28c/0x6b8
[    8.899559][  T599] sp : ffffffc00e733b00
[    8.899560][  T599] x29: ffffffc00e733b00 x28: ffffffc00e733d30 x27: ffffffe8dc297470
[    8.899563][  T599] x26: ffffffe8dc297000 x25: ffffffe8dc297000 x24: ffffffe8dc297000
[    8.899566][  T599] x23: ffffffe8dc0a6200 x22: ffffff880f68bf20 x21: 0000000000000000
[    8.899569][  T599] x20: ffffff880f68bf00 x19: ffffff8801babc00 x18: ffffffc00d7f9058
[    8.899572][  T599] x17: 0000000000088793 x16: ffffff80461cbe00 x15: 9100052952800785
[    8.899575][  T599] x14: 0000000000000200 x13: 0000000000000041 x12: 9100052952800785
[    8.899577][  T599] x11: ffffffe8dc297000 x10: ffffffe8dc297000 x9 : ffffff80461cbc80
[    8.899580][  T599] x8 : ffffff8801babe80 x7 : ffffffe8dc2ec000 x6 : ffffffe8dc2ed000
[    8.899583][  T599] x5 : 000000008020001f x4 : fffffffe2006eae0 x3 : 000000008020001f
[    8.899586][  T599] x2 : ffffff8027c49200 x1 : ffffff8801babc20 x0 : ffffff80461cb3a0
[    8.899589][  T599] Call trace:
[    8.899590][  T599]  gcov_info_add+0x9c/0xb8
[    8.899592][  T599]  gcov_module_notifier+0xbc/0x120
[    8.899595][  T599]  blocking_notifier_call_chain+0xa0/0x11c
[    8.899598][  T599]  do_init_module+0x2a8/0x33c
[    8.899600][  T599]  load_module+0x23cc/0x261c
[    8.899602][  T599]  __arm64_sys_finit_module+0x158/0x194
[    8.899604][  T599]  invoke_syscall+0x94/0x2bc
[    8.899607][  T599]  el0_svc_common+0x1d8/0x34c
[    8.899609][  T599]  do_el0_svc+0x40/0x54
[    8.899611][  T599]  el0_svc+0x94/0x2f0
[    8.899613][  T599]  el0t_64_sync_handler+0x88/0xec
[    8.899615][  T599]  el0t_64_sync+0x1b4/0x1b8
[    8.899618][  T599] Code: f905f56c f86e69ec f86e6a0f 8b0c01ec (f82e6a0c)
[    8.899620][  T599] ---[ end trace ed5218e9e5b6e2e6 ]---

Link: https://lkml.kernel.org/r/1668020497-13142-1-git-send-email-quic_mojha@quicinc.com
Fixes: e178a5beb369 ("gcov: clang support")
Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Tested-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Tom Rix <trix@redhat.com>
Cc: <stable@vger.kernel.org>	[5.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-02 17:41:09 +01:00
Li Huafei
c49cc2c059 kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case
[ Upstream commit 5dd7caf0bdc5d0bae7cf9776b4d739fb09bd5ebb ]

In __unregister_kprobe_top(), if the currently unregistered probe has
post_handler but other child probes of the aggrprobe do not have
post_handler, the post_handler of the aggrprobe is cleared. If this is
a ftrace-based probe, there is a problem. In later calls to
disarm_kprobe(), we will use kprobe_ftrace_ops because post_handler is
NULL. But we're armed with kprobe_ipmodify_ops. This triggers a WARN in
__disarm_kprobe_ftrace() and may even cause use-after-free:

  Failed to disarm kprobe-ftrace at kernel_clone+0x0/0x3c0 (error -2)
  WARNING: CPU: 5 PID: 137 at kernel/kprobes.c:1135 __disarm_kprobe_ftrace.isra.21+0xcf/0xe0
  Modules linked in: testKprobe_007(-)
  CPU: 5 PID: 137 Comm: rmmod Not tainted 6.1.0-rc4-dirty #18
  [...]
  Call Trace:
   <TASK>
   __disable_kprobe+0xcd/0xe0
   __unregister_kprobe_top+0x12/0x150
   ? mutex_lock+0xe/0x30
   unregister_kprobes.part.23+0x31/0xa0
   unregister_kprobe+0x32/0x40
   __x64_sys_delete_module+0x15e/0x260
   ? do_user_addr_fault+0x2cd/0x6b0
   do_syscall_64+0x3a/0x90
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
   [...]

For the kprobe-on-ftrace case, we keep the post_handler setting to
identify this aggrprobe armed with kprobe_ipmodify_ops. This way we
can disarm it correctly.

Link: https://lore.kernel.org/all/20221112070000.35299-1-lihuafei1@huawei.com/

Fixes: 0bc11ed5ab60 ("kprobes: Allow kprobes coexist with livepatch")
Reported-by: Zhao Gongyi <zhaogongyi@huawei.com>
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-26 09:24:50 +01:00
Steven Rostedt (Google)
73cf0ff9a3 ring-buffer: Include dropped pages in counting dirty patches
[ Upstream commit 31029a8b2c7e656a0289194ef16415050ae4c4ac ]

The function ring_buffer_nr_dirty_pages() was created to find out how many
pages are filled in the ring buffer. There's two running counters. One is
incremented whenever a new page is touched (pages_touched) and the other
is whenever a page is read (pages_read). The dirty count is the number
touched minus the number read. This is used to determine if a blocked task
should be woken up if the percentage of the ring buffer it is waiting for
is hit.

The problem is that it does not take into account dropped pages (when the
new writes overwrite pages that were not read). And then the dirty pages
will always be greater than the percentage.

This makes the "buffer_percent" file inaccurate, as the number of dirty
pages end up always being larger than the percentage, event when it's not
and this causes user space to be woken up more than it wants to be.

Add a new counter to keep track of lost pages, and include that in the
accounting of dirty pages so that it is actually accurate.

Link: https://lkml.kernel.org/r/20221021123013.55fb6055@gandalf.local.home

Fixes: 2c2b0a78b3739 ("ring-buffer: Add percentage of ring buffer full to wake up reader")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-26 09:24:49 +01:00
Marco Elver
35c60b4e8c perf: Improve missing SIGTRAP checking
[ Upstream commit bb88f9695460bec25aa30ba9072595025cf6c8af ]

To catch missing SIGTRAP we employ a WARN in __perf_event_overflow(),
which fires if pending_sigtrap was already set: returning to user space
without consuming pending_sigtrap, and then having the event fire again
would re-enter the kernel and trigger the WARN.

This, however, seemed to miss the case where some events not associated
with progress in the user space task can fire and the interrupt handler
runs before the IRQ work meant to consume pending_sigtrap (and generate
the SIGTRAP).

syzbot gifted us this stack trace:

 | WARNING: CPU: 0 PID: 3607 at kernel/events/core.c:9313 __perf_event_overflow
 | Modules linked in:
 | CPU: 0 PID: 3607 Comm: syz-executor100 Not tainted 6.1.0-rc2-syzkaller-00073-g88619e77b33d #0
 | Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
 | RIP: 0010:__perf_event_overflow+0x498/0x540 kernel/events/core.c:9313
 | <...>
 | Call Trace:
 |  <TASK>
 |  perf_swevent_hrtimer+0x34f/0x3c0 kernel/events/core.c:10729
 |  __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 |  __hrtimer_run_queues+0x1c6/0xfb0 kernel/time/hrtimer.c:1749
 |  hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 |  local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 |  __sysvec_apic_timer_interrupt+0x17c/0x640 arch/x86/kernel/apic/apic.c:1113
 |  sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1107
 |  asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
 | <...>
 |  </TASK>

In this case, syzbot produced a program with event type
PERF_TYPE_SOFTWARE and config PERF_COUNT_SW_CPU_CLOCK. The hrtimer
manages to fire again before the IRQ work got a chance to run, all while
never having returned to user space.

Improve the WARN to check for real progress in user space: approximate
this by storing a 32-bit hash of the current IP into pending_sigtrap,
and if an event fires while pending_sigtrap still matches the previous
IP, we assume no progress (false negatives are possible given we could
return to user space and trigger again on the same IP).

Fixes: ca6c21327c6a ("perf: Fix missing SIGTRAPs")
Reported-by: syzbot+b8ded3e2e2c6adde4990@syzkaller.appspotmail.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221031093513.3032814-1-elver@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-26 09:24:49 +01:00
Shang XiaoJing
e57daa7503 tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit()
commit 22ea4ca9631eb137e64e5ab899e9c89cb6670959 upstream.

When test_gen_kprobe_cmd() failed after kprobe_event_gen_cmd_end(), it
will goto delete, which will call kprobe_event_delete() and release the
corresponding resource. However, the trace_array in gen_kretprobe_test
will point to the invalid resource. Set gen_kretprobe_test to NULL
after called kprobe_event_delete() to prevent null-ptr-deref.

BUG: kernel NULL pointer dereference, address: 0000000000000070
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 0 PID: 246 Comm: modprobe Tainted: G        W
6.1.0-rc1-00174-g9522dc5c87da-dirty #248
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
RIP: 0010:__ftrace_set_clr_event_nolock+0x53/0x1b0
Code: e8 82 26 fc ff 49 8b 1e c7 44 24 0c ea ff ff ff 49 39 de 0f 84 3c
01 00 00 c7 44 24 18 00 00 00 00 e8 61 26 fc ff 48 8b 6b 10 <44> 8b 65
70 4c 8b 6d 18 41 f7 c4 00 02 00 00 75 2f
RSP: 0018:ffffc9000159fe00 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88810971d268 RCX: 0000000000000000
RDX: ffff8881080be600 RSI: ffffffff811b48ff RDI: ffff88810971d058
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001
R10: ffffc9000159fe58 R11: 0000000000000001 R12: ffffffffa0001064
R13: ffffffffa000106c R14: ffff88810971d238 R15: 0000000000000000
FS:  00007f89eeff6540(0000) GS:ffff88813b600000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000070 CR3: 000000010599e004 CR4: 0000000000330ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __ftrace_set_clr_event+0x3e/0x60
 trace_array_set_clr_event+0x35/0x50
 ? 0xffffffffa0000000
 kprobe_event_gen_test_exit+0xcd/0x10b [kprobe_event_gen_test]
 __x64_sys_delete_module+0x206/0x380
 ? lockdep_hardirqs_on_prepare+0xd8/0x190
 ? syscall_enter_from_user_mode+0x1c/0x50
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f89eeb061b7

Link: https://lore.kernel.org/all/20221108015130.28326-3-shangxiaojing@huawei.com/

Fixes: 64836248dda2 ("tracing: Add kprobe event command generation test module")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:43 +01:00
Shang XiaoJing
3a41c0f2a5 tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit()
commit e0d75267f59d7084e0468bd68beeb1bf9c71d7c0 upstream.

When trace_get_event_file() failed, gen_kretprobe_test will be assigned
as the error code. If module kprobe_event_gen_test is removed now, the
null pointer dereference will happen in kprobe_event_gen_test_exit().
Check if gen_kprobe_test or gen_kretprobe_test is error code or NULL
before dereference them.

BUG: kernel NULL pointer dereference, address: 0000000000000012
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 3 PID: 2210 Comm: modprobe Not tainted
6.1.0-rc1-00171-g2159299a3b74-dirty #217
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
RIP: 0010:kprobe_event_gen_test_exit+0x1c/0xb5 [kprobe_event_gen_test]
Code: Unable to access opcode bytes at 0xffffffff9ffffff2.
RSP: 0018:ffffc900015bfeb8 EFLAGS: 00010246
RAX: ffffffffffffffea RBX: ffffffffa0002080 RCX: 0000000000000000
RDX: ffffffffa0001054 RSI: ffffffffa0001064 RDI: ffffffffdfc6349c
RBP: ffffffffa0000000 R08: 0000000000000004 R09: 00000000001e95c0
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000800
R13: ffffffffa0002420 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f56b75be540(0000) GS:ffff88813bc00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff9ffffff2 CR3: 000000010874a006 CR4: 0000000000330ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __x64_sys_delete_module+0x206/0x380
 ? lockdep_hardirqs_on_prepare+0xd8/0x190
 ? syscall_enter_from_user_mode+0x1c/0x50
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Link: https://lore.kernel.org/all/20221108015130.28326-2-shangxiaojing@huawei.com/

Fixes: 64836248dda2 ("tracing: Add kprobe event command generation test module")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:43 +01:00
Steven Rostedt (Google)
7291dec4f2 tracing: Fix race where eprobes can be called before the event
commit 94eedf3dded5fb472ce97bfaf3ac1c6c29c35d26 upstream.

The flag that tells the event to call its triggers after reading the event
is set for eprobes after the eprobe is enabled. This leads to a race where
the eprobe may be triggered at the beginning of the event where the record
information is NULL. The eprobe then dereferences the NULL record causing
a NULL kernel pointer bug.

Test for a NULL record to keep this from happening.

Link: https://lore.kernel.org/linux-trace-kernel/20221116192552.1066630-1-rafaelmendsr@gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20221117214249.2addbe10@gandalf.local.home

Cc: Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 7491e2c442781 ("tracing: Add a probe that attaches to trace events")
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reported-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:43 +01:00
Shang XiaoJing
6517b97134 tracing: Fix wild-memory-access in register_synth_event()
commit 1b5f1c34d3f5a664a57a5a7557a50e4e3cc2505c upstream.

In register_synth_event(), if set_synth_event_print_fmt() failed, then
both trace_remove_event_call() and unregister_trace_event() will be
called, which means the trace_event_call will call
__unregister_trace_event() twice. As the result, the second unregister
will causes the wild-memory-access.

register_synth_event
    set_synth_event_print_fmt failed
    trace_remove_event_call
        event_remove
            if call->event.funcs then
            __unregister_trace_event (first call)
    unregister_trace_event
        __unregister_trace_event (second call)

Fix the bug by avoiding to call the second __unregister_trace_event() by
checking if the first one is called.

general protection fault, probably for non-canonical address
	0xfbd59c0000000024: 0000 [#1] SMP KASAN PTI
KASAN: maybe wild-memory-access in range
[0xdead000000000120-0xdead000000000127]
CPU: 0 PID: 3807 Comm: modprobe Not tainted
6.1.0-rc1-00186-g76f33a7eedb4 #299
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
RIP: 0010:unregister_trace_event+0x6e/0x280
Code: 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 0e 02 00 00 48
b8 00 00 00 00 00 fc ff df 4c 8b 63 08 4c 89 e2 48 c1 ea 03 <80> 3c 02
00 0f 85 e2 01 00 00 49 89 2c 24 48 85 ed 74 28 e8 7a 9b
RSP: 0018:ffff88810413f370 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: ffff888105d050b0 RCX: 0000000000000000
RDX: 1bd5a00000000024 RSI: ffff888119e276e0 RDI: ffffffff835a8b20
RBP: dead000000000100 R08: 0000000000000000 R09: fffffbfff0913481
R10: ffffffff8489a407 R11: fffffbfff0913480 R12: dead000000000122
R13: ffff888105d050b8 R14: 0000000000000000 R15: ffff888105d05028
FS:  00007f7823e8d540(0000) GS:ffff888119e00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7823e7ebec CR3: 000000010a058002 CR4: 0000000000330ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __create_synth_event+0x1e37/0x1eb0
 create_or_delete_synth_event+0x110/0x250
 synth_event_run_command+0x2f/0x110
 test_gen_synth_cmd+0x170/0x2eb [synth_event_gen_test]
 synth_event_gen_test_init+0x76/0x9bc [synth_event_gen_test]
 do_one_initcall+0xdb/0x480
 do_init_module+0x1cf/0x680
 load_module+0x6a50/0x70a0
 __do_sys_finit_module+0x12f/0x1c0
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Link: https://lkml.kernel.org/r/20221117012346.22647-3-shangxiaojing@huawei.com

Fixes: 4b147936fa50 ("tracing: Add support for 'synthetic' events")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Cc: stable@vger.kernel.org
Cc: <mhiramat@kernel.org>
Cc: <zanussi@kernel.org>
Cc: <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:43 +01:00
Shang XiaoJing
07ba4f0603 tracing: Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event()
commit a4527fef9afe5c903c718d0cd24609fe9c754250 upstream.

test_gen_synth_cmd() only free buf in fail path, hence buf will leak
when there is no failure. Add kfree(buf) to prevent the memleak. The
same reason and solution in test_empty_synth_event().

unreferenced object 0xffff8881127de000 (size 2048):
  comm "modprobe", pid 247, jiffies 4294972316 (age 78.756s)
  hex dump (first 32 bytes):
    20 67 65 6e 5f 73 79 6e 74 68 5f 74 65 73 74 20   gen_synth_test
    20 70 69 64 5f 74 20 6e 65 78 74 5f 70 69 64 5f   pid_t next_pid_
  backtrace:
    [<000000004254801a>] kmalloc_trace+0x26/0x100
    [<0000000039eb1cf5>] 0xffffffffa00083cd
    [<000000000e8c3bc8>] 0xffffffffa00086ba
    [<00000000c293d1ea>] do_one_initcall+0xdb/0x480
    [<00000000aa189e6d>] do_init_module+0x1cf/0x680
    [<00000000d513222b>] load_module+0x6a50/0x70a0
    [<000000001fd4d529>] __do_sys_finit_module+0x12f/0x1c0
    [<00000000b36c4c0f>] do_syscall_64+0x3f/0x90
    [<00000000bbf20cf3>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
unreferenced object 0xffff8881127df000 (size 2048):
  comm "modprobe", pid 247, jiffies 4294972324 (age 78.728s)
  hex dump (first 32 bytes):
    20 65 6d 70 74 79 5f 73 79 6e 74 68 5f 74 65 73   empty_synth_tes
    74 20 20 70 69 64 5f 74 20 6e 65 78 74 5f 70 69  t  pid_t next_pi
  backtrace:
    [<000000004254801a>] kmalloc_trace+0x26/0x100
    [<00000000d4db9a3d>] 0xffffffffa0008071
    [<00000000c31354a5>] 0xffffffffa00086ce
    [<00000000c293d1ea>] do_one_initcall+0xdb/0x480
    [<00000000aa189e6d>] do_init_module+0x1cf/0x680
    [<00000000d513222b>] load_module+0x6a50/0x70a0
    [<000000001fd4d529>] __do_sys_finit_module+0x12f/0x1c0
    [<00000000b36c4c0f>] do_syscall_64+0x3f/0x90
    [<00000000bbf20cf3>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Link: https://lkml.kernel.org/r/20221117012346.22647-2-shangxiaojing@huawei.com

Cc: <mhiramat@kernel.org>
Cc: <zanussi@kernel.org>
Cc: <fengguang.wu@intel.com>
Cc: stable@vger.kernel.org
Fixes: 9fe41efaca08 ("tracing: Add synth event generation test module")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:43 +01:00
Steven Rostedt (Google)
8b318f3032 tracing/ring-buffer: Have polling block on watermark
commit 42fb0a1e84ff525ebe560e2baf9451ab69127e2b upstream.

Currently the way polling works on the ring buffer is broken. It will
return immediately if there's any data in the ring buffer whereas a read
will block until the watermark (defined by the tracefs buffer_percent file)
is hit.

That is, a select() or poll() will return as if there's data available,
but then the following read will block. This is broken for the way
select()s and poll()s are supposed to work.

Have the polling on the ring buffer also block the same way reads and
splice does on the ring buffer.

Link: https://lkml.kernel.org/r/20221020231427.41be3f26@gandalf.local.home

Cc: Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Primiano Tucci <primiano@google.com>
Cc: stable@vger.kernel.org
Fixes: 1e0d6714aceb7 ("ring-buffer: Do not wake up a splice waiter when page is not full")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:42 +01:00
Wang Yufen
2c21ee020c tracing: Fix memory leak in tracing_read_pipe()
commit 649e72070cbbb8600eb823833e4748f5a0815116 upstream.

kmemleak reports this issue:

unreferenced object 0xffff888105a18900 (size 128):
  comm "test_progs", pid 18933, jiffies 4336275356 (age 22801.766s)
  hex dump (first 32 bytes):
    25 73 00 90 81 88 ff ff 26 05 00 00 42 01 58 04  %s......&...B.X.
    03 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000560143a1>] __kmalloc_node_track_caller+0x4a/0x140
    [<000000006af00822>] krealloc+0x8d/0xf0
    [<00000000c309be6a>] trace_iter_expand_format+0x99/0x150
    [<000000005a53bdb6>] trace_check_vprintf+0x1e0/0x11d0
    [<0000000065629d9d>] trace_event_printf+0xb6/0xf0
    [<000000009a690dc7>] trace_raw_output_bpf_trace_printk+0x89/0xc0
    [<00000000d22db172>] print_trace_line+0x73c/0x1480
    [<00000000cdba76ba>] tracing_read_pipe+0x45c/0x9f0
    [<0000000015b58459>] vfs_read+0x17b/0x7c0
    [<000000004aeee8ed>] ksys_read+0xed/0x1c0
    [<0000000063d3d898>] do_syscall_64+0x3b/0x90
    [<00000000a06dda7f>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

iter->fmt alloced in
  tracing_read_pipe() -> .. ->trace_iter_expand_format(), but not
freed, to fix, add free in tracing_release_pipe()

Link: https://lkml.kernel.org/r/1667819090-4643-1-git-send-email-wangyufen@huawei.com

Cc: stable@vger.kernel.org
Fixes: efbbdaa22bb7 ("tracing: Show real address for trace event arguments")
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:42 +01:00
Daniil Tatianin
00f74b1a98 ring_buffer: Do not deactivate non-existant pages
commit 56f4ca0a79a9f1af98f26c54b9b89ba1f9bcc6bd upstream.

rb_head_page_deactivate() expects cpu_buffer to contain a valid list of
->pages, so verify that the list is actually present before calling it.

Found by Linux Verification Center (linuxtesting.org) with the SVACE
static analysis tool.

Link: https://lkml.kernel.org/r/20221114143129.3534443-1-d-tatianin@yandex-team.ru

Cc: stable@vger.kernel.org
Fixes: 77ae365eca895 ("ring-buffer: make lockless")
Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:42 +01:00
Xiu Jianfeng
1bea037a1a ftrace: Fix null pointer dereference in ftrace_add_mod()
commit 19ba6c8af9382c4c05dc6a0a79af3013b9a35cd0 upstream.

The @ftrace_mod is allocated by kzalloc(), so both the members {prev,next}
of @ftrace_mode->list are NULL, it's not a valid state to call list_del().
If kstrdup() for @ftrace_mod->{func|module} fails, it goes to @out_free
tag and calls free_ftrace_mod() to destroy @ftrace_mod, then list_del()
will write prev->next and next->prev, where null pointer dereference
happens.

BUG: kernel NULL pointer dereference, address: 0000000000000008
Oops: 0002 [#1] PREEMPT SMP NOPTI
Call Trace:
 <TASK>
 ftrace_mod_callback+0x20d/0x220
 ? do_filp_open+0xd9/0x140
 ftrace_process_regex.isra.51+0xbf/0x130
 ftrace_regex_write.isra.52.part.53+0x6e/0x90
 vfs_write+0xee/0x3a0
 ? __audit_filter_op+0xb1/0x100
 ? auditd_test_task+0x38/0x50
 ksys_write+0xa5/0xe0
 do_syscall_64+0x3a/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
Kernel panic - not syncing: Fatal exception

So call INIT_LIST_HEAD() to initialize the list member to fix this issue.

Link: https://lkml.kernel.org/r/20221116015207.30858-1-xiujianfeng@huawei.com

Cc: stable@vger.kernel.org
Fixes: 673feb9d76ab ("ftrace: Add :mod: caching infrastructure to trace_array")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:42 +01:00
Wang Wensheng
fadfcf39fb ftrace: Optimize the allocation for mcount entries
commit bcea02b096333dc74af987cb9685a4dbdd820840 upstream.

If we can't allocate this size, try something smaller with half of the
size. Its order should be decreased by one instead of divided by two.

Link: https://lkml.kernel.org/r/20221109094434.84046-3-wangwensheng4@huawei.com

Cc: <mhiramat@kernel.org>
Cc: <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Fixes: a79008755497d ("ftrace: Allocate the mcount record pages as groups")
Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:42 +01:00
Wang Wensheng
5c5f264289 ftrace: Fix the possible incorrect kernel message
commit 08948caebe93482db1adfd2154eba124f66d161d upstream.

If the number of mcount entries is an integer multiple of
ENTRIES_PER_PAGE, the page count showing on the console would be wrong.

Link: https://lkml.kernel.org/r/20221109094434.84046-2-wangwensheng4@huawei.com

Cc: <mhiramat@kernel.org>
Cc: <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Fixes: 5821e1b74f0d0 ("function tracing: fix wrong pos computing when read buffer has been fulfilled")
Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-26 09:24:42 +01:00
Xu Kuohai
7ff4fa179e bpf: Initialize same number of free nodes for each pcpu_freelist
[ Upstream commit 4b45cd81f737d79d0fbfc0d320a1e518e7f0bbf0 ]

pcpu_freelist_populate() initializes nr_elems / num_possible_cpus() + 1
free nodes for some CPUs, and then possibly one CPU with fewer nodes,
followed by remaining cpus with 0 nodes. For example, when nr_elems == 256
and num_possible_cpus() == 32, CPU 0~27 each gets 9 free nodes, CPU 28 gets
4 free nodes, CPU 29~31 get 0 free nodes, while in fact each CPU should get
8 nodes equally.

This patch initializes nr_elems / num_possible_cpus() free nodes for each
CPU firstly, then allocates the remaining free nodes by one for each CPU
until no free nodes left.

Fixes: e19494edab82 ("bpf: introduce percpu_freelist")
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221110122128.105214-1-xukuohai@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-26 09:24:38 +01:00
Wang Yufen
d494449782 bpf: Fix memory leaks in __check_func_call
[ Upstream commit eb86559a691cea5fa63e57a03ec3dc9c31e97955 ]

kmemleak reports this issue:

unreferenced object 0xffff88817139d000 (size 2048):
  comm "test_progs", pid 33246, jiffies 4307381979 (age 45851.820s)
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000045f075f0>] kmalloc_trace+0x27/0xa0
    [<0000000098b7c90a>] __check_func_call+0x316/0x1230
    [<00000000b4c3c403>] check_helper_call+0x172e/0x4700
    [<00000000aa3875b7>] do_check+0x21d8/0x45e0
    [<000000001147357b>] do_check_common+0x767/0xaf0
    [<00000000b5a595b4>] bpf_check+0x43e3/0x5bc0
    [<0000000011e391b1>] bpf_prog_load+0xf26/0x1940
    [<0000000007f765c0>] __sys_bpf+0xd2c/0x3650
    [<00000000839815d6>] __x64_sys_bpf+0x75/0xc0
    [<00000000946ee250>] do_syscall_64+0x3b/0x90
    [<0000000000506b7f>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

The root case here is: In function prepare_func_exit(), the callee is
not released in the abnormal scenario after "state->curframe--;". To
fix, move "state->curframe--;" to the very bottom of the function,
right when we free callee and reset frame[] pointer to NULL, as Andrii
suggested.

In addition, function __check_func_call() has a similar problem. In
the abnormal scenario before "state->curframe++;", the callee also
should be released by free_func_state().

Fixes: 69c087ba6225 ("bpf: Add bpf_for_each_map_elem() helper")
Fixes: fd978bf7fd31 ("bpf: Add reference tracking to verifier")
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Link: https://lore.kernel.org/r/1667884291-15666-1-git-send-email-wangyufen@huawei.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-26 09:24:36 +01:00
Youlin Li
466ce46f25 bpf: Fix wrong reg type conversion in release_reference()
[ Upstream commit f1db20814af532f85e091231223e5e4818e8464b ]

Some helper functions will allocate memory. To avoid memory leaks, the
verifier requires the eBPF program to release these memories by calling
the corresponding helper functions.

When a resource is released, all pointer registers corresponding to the
resource should be invalidated. The verifier use release_references() to
do this job, by apply  __mark_reg_unknown() to each relevant register.

It will give these registers the type of SCALAR_VALUE. A register that
will contain a pointer value at runtime, but of type SCALAR_VALUE, which
may allow the unprivileged user to get a kernel pointer by storing this
register into a map.

Using __mark_reg_not_init() while NOT allow_ptr_leaks can mitigate this
problem.

Fixes: fd978bf7fd31 ("bpf: Add reference tracking to verifier")
Signed-off-by: Youlin Li <liulin063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221103093440.3161-1-liulin063@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:15 +01:00
Kumar Kartikeya Dwivedi
35d8130f2a bpf: Add helper macro bpf_for_each_reg_in_vstate
[ Upstream commit b239da34203f49c40b5d656220c39647c3ff0b3c ]

For a lot of use cases in future patches, we will want to modify the
state of registers part of some same 'group' (e.g. same ref_obj_id). It
won't just be limited to releasing reference state, but setting a type
flag dynamically based on certain actions, etc.

Hence, we need a way to easily pass a callback to the function that
iterates over all registers in current bpf_verifier_state in all frames
upto (and including) the curframe.

While in C++ we would be able to easily use a lambda to pass state and
the callback together, sadly we aren't using C++ in the kernel. The next
best thing to avoid defining a function for each case seems like
statement expressions in GNU C. The kernel already uses them heavily,
hence they can passed to the macro in the style of a lambda. The
statement expression will then be substituted in the for loop bodies.

Variables __state and __reg are set to current bpf_func_state and reg
for each invocation of the expression inside the passed in verifier
state.

Then, convert mark_ptr_or_null_regs, clear_all_pkt_pointers,
release_reference, find_good_pkt_pointers, find_equal_scalars to
use bpf_for_each_reg_in_vstate.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220904204145.3089-16-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Stable-dep-of: f1db20814af5 ("bpf: Fix wrong reg type conversion in release_reference()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:15 +01:00
Kees Cook
06615967d4 bpf, verifier: Fix memory leak in array reallocation for stack state
[ Upstream commit 42378a9ca55347102bbf86708776061d8fe3ece2 ]

If an error (NULL) is returned by krealloc(), callers of realloc_array()
were setting their allocation pointers to NULL, but on error krealloc()
does not touch the original allocation. This would result in a memory
resource leak. Instead, free the old allocation on the error handling
path.

The memory leak information is as follows as also reported by Zhengchao:

  unreferenced object 0xffff888019801800 (size 256):
  comm "bpf_repo", pid 6490, jiffies 4294959200 (age 17.170s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000b211474b>] __kmalloc_node_track_caller+0x45/0xc0
    [<0000000086712a0b>] krealloc+0x83/0xd0
    [<00000000139aab02>] realloc_array+0x82/0xe2
    [<00000000b1ca41d1>] grow_stack_state+0xfb/0x186
    [<00000000cd6f36d2>] check_mem_access.cold+0x141/0x1341
    [<0000000081780455>] do_check_common+0x5358/0xb350
    [<0000000015f6b091>] bpf_check.cold+0xc3/0x29d
    [<000000002973c690>] bpf_prog_load+0x13db/0x2240
    [<00000000028d1644>] __sys_bpf+0x1605/0x4ce0
    [<00000000053f29bd>] __x64_sys_bpf+0x75/0xb0
    [<0000000056fedaf5>] do_syscall_64+0x35/0x80
    [<000000002bd58261>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: c69431aab67a ("bpf: verifier: Improve function state reallocation")
Reported-by: Zhengchao Shao <shaozhengchao@huawei.com>
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Bill Wendling <morbo@google.com>
Cc: Lorenz Bauer <oss@lmb.io>
Link: https://lore.kernel.org/bpf/20221029025433.2533810-1-keescook@chromium.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:14 +01:00
Steven Rostedt (Google)
b5074df412 ring-buffer: Check for NULL cpu_buffer in ring_buffer_wake_waiters()
commit 7433632c9ff68a991bd0bc38cabf354e9d2de410 upstream.

On some machines the number of listed CPUs may be bigger than the actual
CPUs that exist. The tracing subsystem allocates a per_cpu directory with
access to the per CPU ring buffer via a cpuX file. But to save space, the
ring buffer will only allocate buffers for online CPUs, even though the
CPU array will be as big as the nr_cpu_ids.

With the addition of waking waiters on the ring buffer when closing the
file, the ring_buffer_wake_waiters() now needs to make sure that the
buffer is allocated (with the irq_work allocated with it) before trying to
wake waiters, as it will cause a NULL pointer dereference.

While debugging this, I added a NULL check for the buffer itself (which is
OK to do), and also NULL pointer checks against buffer->buffers (which is
not fine, and will WARN) as well as making sure the CPU number passed in
is within the nr_cpu_ids (which is also not fine if it isn't).

Link: https://lore.kernel.org/all/87h6zklb6n.wl-tiwai@suse.de/
Link: https://lore.kernel.org/all/CAM6Wdxc0KRJMXVAA0Y=u6Jh2V=uWB-_Fn6M4xRuNppfXzL1mUg@mail.gmail.com/
Link: https://lkml.kernel.org/linux-trace-kernel/20221101191009.1e7378c8@rorschach.local.home

Cc: stable@vger.kernel.org
Cc: Steven Noonan <steven.noonan@gmail.com>
Bugzilla: https://bugzilla.opensuse.org/show_bug.cgi?id=1204705
Reported-by: Takashi Iwai <tiwai@suse.de>
Reported-by: Roland Ruckerbauer <roland.rucky@gmail.com>
Fixes: f3ddb74ad079 ("tracing: Wake up ring buffer waiters on closing of the file")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:15:38 +01:00