* [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
@ 2020-08-31 15:12 Masami Hiramatsu
2020-08-31 15:47 ` [External] " Muchun Song
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Masami Hiramatsu @ 2020-08-31 15:12 UTC (permalink / raw)
To: Ingo Molnar, Steven Rostedt
Cc: mhiramat, linux-kernel, Naveen N . Rao, Anil S Keshavamurthy,
David Miller, Muchun Song, Chengming Zhou
Commit 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at
kprobe_ftrace_handler") fixed one bug but not completely fixed yet.
If we run a kprobe_module.tc of ftracetest, kernel showed a warning
as below.
# ./ftracetest test.d/kprobe/kprobe_module.tc
=== Ftrace unit tests ===
[1] Kprobe dynamic event - probing module
...
[ 22.400215] ------------[ cut here ]------------
[ 22.400962] Failed to disarm kprobe-ftrace at trace_printk_irq_work+0x0/0x7e [trace_printk] (-2)
[ 22.402139] WARNING: CPU: 7 PID: 200 at kernel/kprobes.c:1091 __disarm_kprobe_ftrace.isra.0+0x7e/0xa0
[ 22.403358] Modules linked in: trace_printk(-)
[ 22.404028] CPU: 7 PID: 200 Comm: rmmod Not tainted 5.9.0-rc2+ #66
[ 22.404870] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014
[ 22.406139] RIP: 0010:__disarm_kprobe_ftrace.isra.0+0x7e/0xa0
[ 22.406947] Code: 30 8b 03 eb c9 80 3d e5 09 1f 01 00 75 dc 49 8b 34 24 89 c2 48 c7 c7 a0 c2 05 82 89 45 e4 c6 05 cc 09 1f 01 01 e8 a9 c7 f0 ff <0f> 0b 8b 45 e4 eb b9 89 c6 48 c7 c7 70 c2 05 82 89 45 e4 e8 91 c7
[ 22.409544] RSP: 0018:ffffc90000237df0 EFLAGS: 00010286
[ 22.410385] RAX: 0000000000000000 RBX: ffffffff83066024 RCX: 0000000000000000
[ 22.411434] RDX: 0000000000000001 RSI: ffffffff810de8d3 RDI: ffffffff810de8d3
[ 22.412687] RBP: ffffc90000237e10 R08: 0000000000000001 R09: 0000000000000001
[ 22.413762] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88807c478640
[ 22.414852] R13: ffffffff8235ebc0 R14: ffffffffa00060c0 R15: 0000000000000000
[ 22.415941] FS: 00000000019d48c0(0000) GS:ffff88807d7c0000(0000) knlGS:0000000000000000
[ 22.417264] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 22.418176] CR2: 00000000005bb7e3 CR3: 0000000078f7a000 CR4: 00000000000006a0
[ 22.419309] Call Trace:
[ 22.419990] kill_kprobe+0x94/0x160
[ 22.420652] kprobes_module_callback+0x64/0x230
[ 22.421470] notifier_call_chain+0x4f/0x70
[ 22.422184] blocking_notifier_call_chain+0x49/0x70
[ 22.422979] __x64_sys_delete_module+0x1ac/0x240
[ 22.423733] do_syscall_64+0x38/0x50
[ 22.424366] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 22.425176] RIP: 0033:0x4bb81d
[ 22.425741] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e0 ff ff ff f7 d8 64 89 01 48
[ 22.428726] RSP: 002b:00007ffc70fef008 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0
[ 22.430169] RAX: ffffffffffffffda RBX: 00000000019d48a0 RCX: 00000000004bb81d
[ 22.431375] RDX: 0000000000000000 RSI: 0000000000000880 RDI: 00007ffc70fef028
[ 22.432543] RBP: 0000000000000880 R08: 00000000ffffffff R09: 00007ffc70fef320
[ 22.433692] R10: 0000000000656300 R11: 0000000000000246 R12: 00007ffc70fef028
[ 22.434635] R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000
[ 22.435682] irq event stamp: 1169
[ 22.436240] hardirqs last enabled at (1179): [<ffffffff810df542>] console_unlock+0x422/0x580
[ 22.437466] hardirqs last disabled at (1188): [<ffffffff810df19b>] console_unlock+0x7b/0x580
[ 22.438608] softirqs last enabled at (866): [<ffffffff81c0038e>] __do_softirq+0x38e/0x490
[ 22.439637] softirqs last disabled at (859): [<ffffffff81a00f42>] asm_call_on_stack+0x12/0x20
[ 22.440690] ---[ end trace 1e7ce7e1e4567276 ]---
[ 22.472832] trace_kprobe: This probe might be able to register after target module is loaded. Continue.
This is because the kill_kprobe() calls disarm_kprobe_ftrace() even
if the given probe is not enabled. In that case, ftrace_set_filter_ip()
fails because the given probe point is not registered to ftrace.
Fix to check the given (going) probe is enabled before invoking
disarm_kprobe_ftrace().
Fixes: 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
kernel/kprobes.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 287b263c9cb9..d43b48ecdb4f 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2159,9 +2159,10 @@ static void kill_kprobe(struct kprobe *p)
/*
* The module is going away. We should disarm the kprobe which
- * is using ftrace.
+ * is using ftrace, because ftrace framework is still available at
+ * MODULE_STATE_GOING notification.
*/
- if (kprobe_ftrace(p))
+ if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed)
disarm_kprobe_ftrace(p);
}
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [External] [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
2020-08-31 15:12 [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace() Masami Hiramatsu
@ 2020-08-31 15:47 ` Muchun Song
2020-08-31 22:24 ` Masami Hiramatsu
2020-09-12 2:27 ` Masami Hiramatsu
2020-09-14 17:16 ` [tip: perf/kprobes] " tip-bot2 for Masami Hiramatsu
2 siblings, 1 reply; 6+ messages in thread
From: Muchun Song @ 2020-08-31 15:47 UTC (permalink / raw)
To: Masami Hiramatsu
Cc: Ingo Molnar, Steven Rostedt, LKML, Naveen N . Rao,
Anil S Keshavamurthy, David Miller, Chengming Zhou
On Mon, Aug 31, 2020 at 11:12 PM Masami Hiramatsu <mhiramat@kernel.org> wrote:
>
> Commit 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at
> kprobe_ftrace_handler") fixed one bug but not completely fixed yet.
> If we run a kprobe_module.tc of ftracetest, kernel showed a warning
> as below.
>
>
> # ./ftracetest test.d/kprobe/kprobe_module.tc
> === Ftrace unit tests ===
> [1] Kprobe dynamic event - probing module
> ...
> [ 22.400215] ------------[ cut here ]------------
> [ 22.400962] Failed to disarm kprobe-ftrace at trace_printk_irq_work+0x0/0x7e [trace_printk] (-2)
> [ 22.402139] WARNING: CPU: 7 PID: 200 at kernel/kprobes.c:1091 __disarm_kprobe_ftrace.isra.0+0x7e/0xa0
> [ 22.403358] Modules linked in: trace_printk(-)
> [ 22.404028] CPU: 7 PID: 200 Comm: rmmod Not tainted 5.9.0-rc2+ #66
> [ 22.404870] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014
> [ 22.406139] RIP: 0010:__disarm_kprobe_ftrace.isra.0+0x7e/0xa0
> [ 22.406947] Code: 30 8b 03 eb c9 80 3d e5 09 1f 01 00 75 dc 49 8b 34 24 89 c2 48 c7 c7 a0 c2 05 82 89 45 e4 c6 05 cc 09 1f 01 01 e8 a9 c7 f0 ff <0f> 0b 8b 45 e4 eb b9 89 c6 48 c7 c7 70 c2 05 82 89 45 e4 e8 91 c7
> [ 22.409544] RSP: 0018:ffffc90000237df0 EFLAGS: 00010286
> [ 22.410385] RAX: 0000000000000000 RBX: ffffffff83066024 RCX: 0000000000000000
> [ 22.411434] RDX: 0000000000000001 RSI: ffffffff810de8d3 RDI: ffffffff810de8d3
> [ 22.412687] RBP: ffffc90000237e10 R08: 0000000000000001 R09: 0000000000000001
> [ 22.413762] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88807c478640
> [ 22.414852] R13: ffffffff8235ebc0 R14: ffffffffa00060c0 R15: 0000000000000000
> [ 22.415941] FS: 00000000019d48c0(0000) GS:ffff88807d7c0000(0000) knlGS:0000000000000000
> [ 22.417264] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 22.418176] CR2: 00000000005bb7e3 CR3: 0000000078f7a000 CR4: 00000000000006a0
> [ 22.419309] Call Trace:
> [ 22.419990] kill_kprobe+0x94/0x160
> [ 22.420652] kprobes_module_callback+0x64/0x230
> [ 22.421470] notifier_call_chain+0x4f/0x70
> [ 22.422184] blocking_notifier_call_chain+0x49/0x70
> [ 22.422979] __x64_sys_delete_module+0x1ac/0x240
> [ 22.423733] do_syscall_64+0x38/0x50
> [ 22.424366] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [ 22.425176] RIP: 0033:0x4bb81d
> [ 22.425741] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e0 ff ff ff f7 d8 64 89 01 48
> [ 22.428726] RSP: 002b:00007ffc70fef008 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0
> [ 22.430169] RAX: ffffffffffffffda RBX: 00000000019d48a0 RCX: 00000000004bb81d
> [ 22.431375] RDX: 0000000000000000 RSI: 0000000000000880 RDI: 00007ffc70fef028
> [ 22.432543] RBP: 0000000000000880 R08: 00000000ffffffff R09: 00007ffc70fef320
> [ 22.433692] R10: 0000000000656300 R11: 0000000000000246 R12: 00007ffc70fef028
> [ 22.434635] R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000
> [ 22.435682] irq event stamp: 1169
> [ 22.436240] hardirqs last enabled at (1179): [<ffffffff810df542>] console_unlock+0x422/0x580
> [ 22.437466] hardirqs last disabled at (1188): [<ffffffff810df19b>] console_unlock+0x7b/0x580
> [ 22.438608] softirqs last enabled at (866): [<ffffffff81c0038e>] __do_softirq+0x38e/0x490
> [ 22.439637] softirqs last disabled at (859): [<ffffffff81a00f42>] asm_call_on_stack+0x12/0x20
> [ 22.440690] ---[ end trace 1e7ce7e1e4567276 ]---
> [ 22.472832] trace_kprobe: This probe might be able to register after target module is loaded. Continue.
>
>
> This is because the kill_kprobe() calls disarm_kprobe_ftrace() even
> if the given probe is not enabled. In that case, ftrace_set_filter_ip()
> fails because the given probe point is not registered to ftrace.
Does the following patch solve this issue? Thanks.
kprobes: Fix kill kprobe which has been marked as gone
https://lkml.org/lkml/2020/8/19/1496
>
> Fix to check the given (going) probe is enabled before invoking
> disarm_kprobe_ftrace().
>
> Fixes: 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler")
> Cc: stable@vger.kernel.org
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> kernel/kprobes.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index 287b263c9cb9..d43b48ecdb4f 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -2159,9 +2159,10 @@ static void kill_kprobe(struct kprobe *p)
>
> /*
> * The module is going away. We should disarm the kprobe which
> - * is using ftrace.
> + * is using ftrace, because ftrace framework is still available at
> + * MODULE_STATE_GOING notification.
> */
> - if (kprobe_ftrace(p))
> + if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed)
> disarm_kprobe_ftrace(p);
> }
>
>
--
Yours,
Muchun
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [External] [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
2020-08-31 15:47 ` [External] " Muchun Song
@ 2020-08-31 22:24 ` Masami Hiramatsu
0 siblings, 0 replies; 6+ messages in thread
From: Masami Hiramatsu @ 2020-08-31 22:24 UTC (permalink / raw)
To: Muchun Song
Cc: Ingo Molnar, Steven Rostedt, LKML, Naveen N . Rao,
Anil S Keshavamurthy, David Miller, Chengming Zhou
Hi Muchun,
On Mon, 31 Aug 2020 23:47:14 +0800
Muchun Song <songmuchun@bytedance.com> wrote:
> On Mon, Aug 31, 2020 at 11:12 PM Masami Hiramatsu <mhiramat@kernel.org> wrote:
> >
> > Commit 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at
> > kprobe_ftrace_handler") fixed one bug but not completely fixed yet.
> > If we run a kprobe_module.tc of ftracetest, kernel showed a warning
> > as below.
> >
> >
> > # ./ftracetest test.d/kprobe/kprobe_module.tc
> > === Ftrace unit tests ===
> > [1] Kprobe dynamic event - probing module
> > ...
> > [ 22.400215] ------------[ cut here ]------------
> > [ 22.400962] Failed to disarm kprobe-ftrace at trace_printk_irq_work+0x0/0x7e [trace_printk] (-2)
> > [ 22.402139] WARNING: CPU: 7 PID: 200 at kernel/kprobes.c:1091 __disarm_kprobe_ftrace.isra.0+0x7e/0xa0
> > [ 22.403358] Modules linked in: trace_printk(-)
> > [ 22.404028] CPU: 7 PID: 200 Comm: rmmod Not tainted 5.9.0-rc2+ #66
> > [ 22.404870] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014
> > [ 22.406139] RIP: 0010:__disarm_kprobe_ftrace.isra.0+0x7e/0xa0
> > [ 22.406947] Code: 30 8b 03 eb c9 80 3d e5 09 1f 01 00 75 dc 49 8b 34 24 89 c2 48 c7 c7 a0 c2 05 82 89 45 e4 c6 05 cc 09 1f 01 01 e8 a9 c7 f0 ff <0f> 0b 8b 45 e4 eb b9 89 c6 48 c7 c7 70 c2 05 82 89 45 e4 e8 91 c7
> > [ 22.409544] RSP: 0018:ffffc90000237df0 EFLAGS: 00010286
> > [ 22.410385] RAX: 0000000000000000 RBX: ffffffff83066024 RCX: 0000000000000000
> > [ 22.411434] RDX: 0000000000000001 RSI: ffffffff810de8d3 RDI: ffffffff810de8d3
> > [ 22.412687] RBP: ffffc90000237e10 R08: 0000000000000001 R09: 0000000000000001
> > [ 22.413762] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88807c478640
> > [ 22.414852] R13: ffffffff8235ebc0 R14: ffffffffa00060c0 R15: 0000000000000000
> > [ 22.415941] FS: 00000000019d48c0(0000) GS:ffff88807d7c0000(0000) knlGS:0000000000000000
> > [ 22.417264] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > [ 22.418176] CR2: 00000000005bb7e3 CR3: 0000000078f7a000 CR4: 00000000000006a0
> > [ 22.419309] Call Trace:
> > [ 22.419990] kill_kprobe+0x94/0x160
> > [ 22.420652] kprobes_module_callback+0x64/0x230
> > [ 22.421470] notifier_call_chain+0x4f/0x70
> > [ 22.422184] blocking_notifier_call_chain+0x49/0x70
> > [ 22.422979] __x64_sys_delete_module+0x1ac/0x240
> > [ 22.423733] do_syscall_64+0x38/0x50
> > [ 22.424366] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> > [ 22.425176] RIP: 0033:0x4bb81d
> > [ 22.425741] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e0 ff ff ff f7 d8 64 89 01 48
> > [ 22.428726] RSP: 002b:00007ffc70fef008 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0
> > [ 22.430169] RAX: ffffffffffffffda RBX: 00000000019d48a0 RCX: 00000000004bb81d
> > [ 22.431375] RDX: 0000000000000000 RSI: 0000000000000880 RDI: 00007ffc70fef028
> > [ 22.432543] RBP: 0000000000000880 R08: 00000000ffffffff R09: 00007ffc70fef320
> > [ 22.433692] R10: 0000000000656300 R11: 0000000000000246 R12: 00007ffc70fef028
> > [ 22.434635] R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000
> > [ 22.435682] irq event stamp: 1169
> > [ 22.436240] hardirqs last enabled at (1179): [<ffffffff810df542>] console_unlock+0x422/0x580
> > [ 22.437466] hardirqs last disabled at (1188): [<ffffffff810df19b>] console_unlock+0x7b/0x580
> > [ 22.438608] softirqs last enabled at (866): [<ffffffff81c0038e>] __do_softirq+0x38e/0x490
> > [ 22.439637] softirqs last disabled at (859): [<ffffffff81a00f42>] asm_call_on_stack+0x12/0x20
> > [ 22.440690] ---[ end trace 1e7ce7e1e4567276 ]---
> > [ 22.472832] trace_kprobe: This probe might be able to register after target module is loaded. Continue.
> >
> >
> > This is because the kill_kprobe() calls disarm_kprobe_ftrace() even
> > if the given probe is not enabled. In that case, ftrace_set_filter_ip()
> > fails because the given probe point is not registered to ftrace.
>
> Does the following patch solve this issue? Thanks.
>
> kprobes: Fix kill kprobe which has been marked as gone
> https://lkml.org/lkml/2020/8/19/1496
No, your patch skips all gone probes, but this one disabled ftrace
probes (not gone yet).
Thank you,
--
Masami Hiramatsu <mhiramat@kernel.org>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
2020-08-31 15:12 [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace() Masami Hiramatsu
2020-08-31 15:47 ` [External] " Muchun Song
@ 2020-09-12 2:27 ` Masami Hiramatsu
2020-09-18 15:52 ` Steven Rostedt
2020-09-14 17:16 ` [tip: perf/kprobes] " tip-bot2 for Masami Hiramatsu
2 siblings, 1 reply; 6+ messages in thread
From: Masami Hiramatsu @ 2020-09-12 2:27 UTC (permalink / raw)
To: Masami Hiramatsu, Ingo Molnar
Cc: Ingo Molnar, Steven Rostedt, linux-kernel, Naveen N . Rao,
Anil S Keshavamurthy, David Miller, Muchun Song, Chengming Zhou,
Peter Zijlstra, x86
Hi Ingo,
Could you also pick this fix to fix the reproducible warning?
Thank you,
On Tue, 1 Sep 2020 00:12:07 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:
> Commit 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at
> kprobe_ftrace_handler") fixed one bug but not completely fixed yet.
> If we run a kprobe_module.tc of ftracetest, kernel showed a warning
> as below.
>
>
> # ./ftracetest test.d/kprobe/kprobe_module.tc
> === Ftrace unit tests ===
> [1] Kprobe dynamic event - probing module
> ...
> [ 22.400215] ------------[ cut here ]------------
> [ 22.400962] Failed to disarm kprobe-ftrace at trace_printk_irq_work+0x0/0x7e [trace_printk] (-2)
> [ 22.402139] WARNING: CPU: 7 PID: 200 at kernel/kprobes.c:1091 __disarm_kprobe_ftrace.isra.0+0x7e/0xa0
> [ 22.403358] Modules linked in: trace_printk(-)
> [ 22.404028] CPU: 7 PID: 200 Comm: rmmod Not tainted 5.9.0-rc2+ #66
> [ 22.404870] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014
> [ 22.406139] RIP: 0010:__disarm_kprobe_ftrace.isra.0+0x7e/0xa0
> [ 22.406947] Code: 30 8b 03 eb c9 80 3d e5 09 1f 01 00 75 dc 49 8b 34 24 89 c2 48 c7 c7 a0 c2 05 82 89 45 e4 c6 05 cc 09 1f 01 01 e8 a9 c7 f0 ff <0f> 0b 8b 45 e4 eb b9 89 c6 48 c7 c7 70 c2 05 82 89 45 e4 e8 91 c7
> [ 22.409544] RSP: 0018:ffffc90000237df0 EFLAGS: 00010286
> [ 22.410385] RAX: 0000000000000000 RBX: ffffffff83066024 RCX: 0000000000000000
> [ 22.411434] RDX: 0000000000000001 RSI: ffffffff810de8d3 RDI: ffffffff810de8d3
> [ 22.412687] RBP: ffffc90000237e10 R08: 0000000000000001 R09: 0000000000000001
> [ 22.413762] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88807c478640
> [ 22.414852] R13: ffffffff8235ebc0 R14: ffffffffa00060c0 R15: 0000000000000000
> [ 22.415941] FS: 00000000019d48c0(0000) GS:ffff88807d7c0000(0000) knlGS:0000000000000000
> [ 22.417264] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 22.418176] CR2: 00000000005bb7e3 CR3: 0000000078f7a000 CR4: 00000000000006a0
> [ 22.419309] Call Trace:
> [ 22.419990] kill_kprobe+0x94/0x160
> [ 22.420652] kprobes_module_callback+0x64/0x230
> [ 22.421470] notifier_call_chain+0x4f/0x70
> [ 22.422184] blocking_notifier_call_chain+0x49/0x70
> [ 22.422979] __x64_sys_delete_module+0x1ac/0x240
> [ 22.423733] do_syscall_64+0x38/0x50
> [ 22.424366] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [ 22.425176] RIP: 0033:0x4bb81d
> [ 22.425741] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e0 ff ff ff f7 d8 64 89 01 48
> [ 22.428726] RSP: 002b:00007ffc70fef008 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0
> [ 22.430169] RAX: ffffffffffffffda RBX: 00000000019d48a0 RCX: 00000000004bb81d
> [ 22.431375] RDX: 0000000000000000 RSI: 0000000000000880 RDI: 00007ffc70fef028
> [ 22.432543] RBP: 0000000000000880 R08: 00000000ffffffff R09: 00007ffc70fef320
> [ 22.433692] R10: 0000000000656300 R11: 0000000000000246 R12: 00007ffc70fef028
> [ 22.434635] R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000
> [ 22.435682] irq event stamp: 1169
> [ 22.436240] hardirqs last enabled at (1179): [<ffffffff810df542>] console_unlock+0x422/0x580
> [ 22.437466] hardirqs last disabled at (1188): [<ffffffff810df19b>] console_unlock+0x7b/0x580
> [ 22.438608] softirqs last enabled at (866): [<ffffffff81c0038e>] __do_softirq+0x38e/0x490
> [ 22.439637] softirqs last disabled at (859): [<ffffffff81a00f42>] asm_call_on_stack+0x12/0x20
> [ 22.440690] ---[ end trace 1e7ce7e1e4567276 ]---
> [ 22.472832] trace_kprobe: This probe might be able to register after target module is loaded. Continue.
>
>
> This is because the kill_kprobe() calls disarm_kprobe_ftrace() even
> if the given probe is not enabled. In that case, ftrace_set_filter_ip()
> fails because the given probe point is not registered to ftrace.
>
> Fix to check the given (going) probe is enabled before invoking
> disarm_kprobe_ftrace().
>
> Fixes: 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler")
> Cc: stable@vger.kernel.org
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> kernel/kprobes.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index 287b263c9cb9..d43b48ecdb4f 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -2159,9 +2159,10 @@ static void kill_kprobe(struct kprobe *p)
>
> /*
> * The module is going away. We should disarm the kprobe which
> - * is using ftrace.
> + * is using ftrace, because ftrace framework is still available at
> + * MODULE_STATE_GOING notification.
> */
> - if (kprobe_ftrace(p))
> + if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed)
> disarm_kprobe_ftrace(p);
> }
>
>
--
Masami Hiramatsu <mhiramat@kernel.org>
^ permalink raw reply [flat|nested] 6+ messages in thread
* [tip: perf/kprobes] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
2020-08-31 15:12 [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace() Masami Hiramatsu
2020-08-31 15:47 ` [External] " Muchun Song
2020-09-12 2:27 ` Masami Hiramatsu
@ 2020-09-14 17:16 ` tip-bot2 for Masami Hiramatsu
2 siblings, 0 replies; 6+ messages in thread
From: tip-bot2 for Masami Hiramatsu @ 2020-09-14 17:16 UTC (permalink / raw)
To: linux-tip-commits; +Cc: Masami Hiramatsu, Ingo Molnar, stable, x86, LKML
The following commit has been merged into the perf/kprobes branch of tip:
Commit-ID: bcb53209be5cb32d485507452edda19b78f31d84
Gitweb: https://git.kernel.org/tip/bcb53209be5cb32d485507452edda19b78f31d84
Author: Masami Hiramatsu <mhiramat@kernel.org>
AuthorDate: Tue, 01 Sep 2020 00:12:07 +09:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Mon, 14 Sep 2020 11:20:03 +02:00
kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
Commit:
0cb2f1372baa ("kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler")
fixed one bug but the underlying bugs are not completely fixed yet.
If we run a kprobe_module.tc of ftracetest, a warning triggers:
# ./ftracetest test.d/kprobe/kprobe_module.tc
=== Ftrace unit tests ===
[1] Kprobe dynamic event - probing module
...
------------[ cut here ]------------
Failed to disarm kprobe-ftrace at trace_printk_irq_work+0x0/0x7e [trace_printk] (-2)
WARNING: CPU: 7 PID: 200 at kernel/kprobes.c:1091 __disarm_kprobe_ftrace.isra.0+0x7e/0xa0
This is because the kill_kprobe() calls disarm_kprobe_ftrace() even
if the given probe is not enabled. In that case, ftrace_set_filter_ip()
fails because the given probe point is not registered to ftrace.
Fix to check the given (going) probe is enabled before invoking
disarm_kprobe_ftrace().
Fixes: 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/159888672694.1411785.5987998076694782591.stgit@devnote2
---
kernel/kprobes.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 732a701..3b61ae8 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2235,9 +2235,10 @@ static void kill_kprobe(struct kprobe *p)
/*
* The module is going away. We should disarm the kprobe which
- * is using ftrace.
+ * is using ftrace, because ftrace framework is still available at
+ * MODULE_STATE_GOING notification.
*/
- if (kprobe_ftrace(p))
+ if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed)
disarm_kprobe_ftrace(p);
}
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
2020-09-12 2:27 ` Masami Hiramatsu
@ 2020-09-18 15:52 ` Steven Rostedt
0 siblings, 0 replies; 6+ messages in thread
From: Steven Rostedt @ 2020-09-18 15:52 UTC (permalink / raw)
To: Masami Hiramatsu
Cc: Ingo Molnar, Ingo Molnar, linux-kernel, Naveen N . Rao,
Anil S Keshavamurthy, David Miller, Muchun Song, Chengming Zhou,
Peter Zijlstra, x86
On Sat, 12 Sep 2020 11:27:49 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:
> Hi Ingo,
>
> Could you also pick this fix to fix the reproducible warning?
>
>
If Ingo hasn't done this already, I'll pick it up now and start putting it
through my tests.
Thanks Masami!
-- Steve
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-09-18 15:52 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-31 15:12 [BUGFIX PATCH] kprobes: Fix to check probe enabled before disarm_kprobe_ftrace() Masami Hiramatsu
2020-08-31 15:47 ` [External] " Muchun Song
2020-08-31 22:24 ` Masami Hiramatsu
2020-09-12 2:27 ` Masami Hiramatsu
2020-09-18 15:52 ` Steven Rostedt
2020-09-14 17:16 ` [tip: perf/kprobes] " tip-bot2 for Masami Hiramatsu
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).