From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Kuniyuki Iwashima <kuniyu@amazon.com>,
Ayushman Dutta <ayudutta@amazon.com>,
"Naveen N. Rao" <naveen.n.rao@linux.ibm.com>,
Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>,
"David S. Miller" <davem@davemloft.net>,
Masami Hiramatsu <mhiramat@kernel.org>,
Wang Nan <wangnan0@huawei.com>,
Kuniyuki Iwashima <kuni1840@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH 5.10 29/37] kprobes: dont call disarm_kprobe() for disabled kprobes
Date: Fri, 2 Sep 2022 14:19:51 +0200 [thread overview]
Message-ID: <20220902121400.082172669@linuxfoundation.org> (raw)
In-Reply-To: <20220902121359.177846782@linuxfoundation.org>
From: Kuniyuki Iwashima <kuniyu@amazon.com>
commit 9c80e79906b4ca440d09e7f116609262bb747909 upstream.
The assumption in __disable_kprobe() is wrong, and it could try to disarm
an already disarmed kprobe and fire the WARN_ONCE() below. [0] We can
easily reproduce this issue.
1. Write 0 to /sys/kernel/debug/kprobes/enabled.
# echo 0 > /sys/kernel/debug/kprobes/enabled
2. Run execsnoop. At this time, one kprobe is disabled.
# /usr/share/bcc/tools/execsnoop &
[1] 2460
PCOMM PID PPID RET ARGS
# cat /sys/kernel/debug/kprobes/list
ffffffff91345650 r __x64_sys_execve+0x0 [FTRACE]
ffffffff91345650 k __x64_sys_execve+0x0 [DISABLED][FTRACE]
3. Write 1 to /sys/kernel/debug/kprobes/enabled, which changes
kprobes_all_disarmed to false but does not arm the disabled kprobe.
# echo 1 > /sys/kernel/debug/kprobes/enabled
# cat /sys/kernel/debug/kprobes/list
ffffffff91345650 r __x64_sys_execve+0x0 [FTRACE]
ffffffff91345650 k __x64_sys_execve+0x0 [DISABLED][FTRACE]
4. Kill execsnoop, when __disable_kprobe() calls disarm_kprobe() for the
disabled kprobe and hits the WARN_ONCE() in __disarm_kprobe_ftrace().
# fg
/usr/share/bcc/tools/execsnoop
^C
Actually, WARN_ONCE() is fired twice, and __unregister_kprobe_top() misses
some cleanups and leaves the aggregated kprobe in the hash table. Then,
__unregister_trace_kprobe() initialises tk->rp.kp.list and creates an
infinite loop like this.
aggregated kprobe.list -> kprobe.list -.
^ |
'.__.'
In this situation, these commands fall into the infinite loop and result
in RCU stall or soft lockup.
cat /sys/kernel/debug/kprobes/list : show_kprobe_addr() enters into the
infinite loop with RCU.
/usr/share/bcc/tools/execsnoop : warn_kprobe_rereg() holds kprobe_mutex,
and __get_valid_kprobe() is stuck in
the loop.
To avoid the issue, make sure we don't call disarm_kprobe() for disabled
kprobes.
[0]
Failed to disarm kprobe-ftrace at __x64_sys_execve+0x0/0x40 (error -2)
WARNING: CPU: 6 PID: 2460 at kernel/kprobes.c:1130 __disarm_kprobe_ftrace.isra.19 (kernel/kprobes.c:1129)
Modules linked in: ena
CPU: 6 PID: 2460 Comm: execsnoop Not tainted 5.19.0+ #28
Hardware name: Amazon EC2 c5.2xlarge/, BIOS 1.0 10/16/2017
RIP: 0010:__disarm_kprobe_ftrace.isra.19 (kernel/kprobes.c:1129)
Code: 24 8b 02 eb c1 80 3d c4 83 f2 01 00 75 d4 48 8b 75 00 89 c2 48 c7 c7 90 fa 0f 92 89 04 24 c6 05 ab 83 01 e8 e4 94 f0 ff <0f> 0b 8b 04 24 eb b1 89 c6 48 c7 c7 60 fa 0f 92 89 04 24 e8 cc 94
RSP: 0018:ffff9e6ec154bd98 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffffff930f7b00 RCX: 0000000000000001
RDX: 0000000080000001 RSI: ffffffff921461c5 RDI: 00000000ffffffff
RBP: ffff89c504286da8 R08: 0000000000000000 R09: c0000000fffeffff
R10: 0000000000000000 R11: ffff9e6ec154bc28 R12: ffff89c502394e40
R13: ffff89c502394c00 R14: ffff9e6ec154bc00 R15: 0000000000000000
FS: 00007fe800398740(0000) GS:ffff89c812d80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00057f010 CR3: 0000000103b54006 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
__disable_kprobe (kernel/kprobes.c:1716)
disable_kprobe (kernel/kprobes.c:2392)
__disable_trace_kprobe (kernel/trace/trace_kprobe.c:340)
disable_trace_kprobe (kernel/trace/trace_kprobe.c:429)
perf_trace_event_unreg.isra.2 (./include/linux/tracepoint.h:93 kernel/trace/trace_event_perf.c:168)
perf_kprobe_destroy (kernel/trace/trace_event_perf.c:295)
_free_event (kernel/events/core.c:4971)
perf_event_release_kernel (kernel/events/core.c:5176)
perf_release (kernel/events/core.c:5186)
__fput (fs/file_table.c:321)
task_work_run (./include/linux/sched.h:2056 (discriminator 1) kernel/task_work.c:179 (discriminator 1))
exit_to_user_mode_prepare (./include/linux/resume_user_mode.h:49 kernel/entry/common.c:169 kernel/entry/common.c:201)
syscall_exit_to_user_mode (./arch/x86/include/asm/jump_label.h:55 ./arch/x86/include/asm/nospec-branch.h:384 ./arch/x86/include/asm/entry-common.h:94 kernel/entry/common.c:133 kernel/entry/common.c:296)
do_syscall_64 (arch/x86/entry/common.c:87)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
RIP: 0033:0x7fe7ff210654
Code: 15 79 89 20 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb be 0f 1f 00 8b 05 9a cd 20 00 48 63 ff 85 c0 75 11 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 3a f3 c3 48 83 ec 18 48 89 7c 24 08 e8 34 fc
RSP: 002b:00007ffdbd1d3538 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 00007fe7ff210654
RDX: 0000000000000000 RSI: 0000000000002401 RDI: 0000000000000008
RBP: 0000000000000000 R08: 94ae31d6fda838a4 R0900007fe8001c9d30
R10: 00007ffdbd1d34b0 R11: 0000000000000246 R12: 00007ffdbd1d3600
R13: 0000000000000000 R14: fffffffffffffffc R15: 00007ffdbd1d3560
</TASK>
Link: https://lkml.kernel.org/r/20220813020509.90805-1-kuniyu@amazon.com
Fixes: 69d54b916d83 ("kprobes: makes kprobes/enabled works correctly for optimized kprobes.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reported-by: Ayushman Dutta <ayudutta@amazon.com>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: Kuniyuki Iwashima <kuni1840@gmail.com>
Cc: Ayushman Dutta <ayudutta@amazon.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/kprobes.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1786,11 +1786,12 @@ static struct kprobe *__disable_kprobe(s
/* Try to disarm and disable this/parent probe */
if (p == orig_p || aggr_kprobe_disabled(orig_p)) {
/*
- * If kprobes_all_disarmed is set, orig_p
- * should have already been disarmed, so
- * skip unneed disarming process.
+ * Don't be lazy here. Even if 'kprobes_all_disarmed'
+ * is false, 'orig_p' might not have been armed yet.
+ * Note arm_all_kprobes() __tries__ to arm all kprobes
+ * on the best effort basis.
*/
- if (!kprobes_all_disarmed) {
+ if (!kprobes_all_disarmed && !kprobe_disabled(orig_p)) {
ret = disarm_kprobe(orig_p, true);
if (ret) {
p->flags &= ~KPROBE_FLAG_DISABLED;
next prev parent reply other threads:[~2022-09-02 12:59 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-02 12:19 [PATCH 5.10 00/37] 5.10.141-rc1 review Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 01/37] mm: Force TLB flush for PFNMAP mappings before unlink_file_vma() Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 02/37] x86/nospec: Unwreck the RSB stuffing Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 03/37] x86/nospec: Fix i386 " Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 04/37] crypto: lib - remove unneeded selection of XOR_BLOCKS Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 05/37] s390/mm: do not trigger write fault when vma does not allow VM_WRITE Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 06/37] kbuild: Fix include path in scripts/Makefile.modpost Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 07/37] Bluetooth: L2CAP: Fix build errors in some archs Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 08/37] Revert "PCI/portdrv: Dont disable AER reporting in get_port_device_capability()" Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 09/37] HID: steam: Prevent NULL pointer dereference in steam_{recv,send}_report Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 10/37] udmabuf: Set the DMA mask for the udmabuf device (v2) Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 11/37] media: pvrusb2: fix memory leak in pvr_probe Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 12/37] HID: hidraw: fix memory leak in hidraw_release() Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 13/37] net: fix refcount bug in sk_psock_get (2) Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 14/37] fbdev: fb_pm2fb: Avoid potential divide by zero error Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 15/37] ftrace: Fix NULL pointer dereference in is_ftrace_trampoline when ftrace is dead Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 16/37] bpf: Dont redirect packets with invalid pkt_len Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 17/37] mm/rmap: Fix anon_vma->degree ambiguity leading to double-reuse Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 18/37] mmc: mtk-sd: Clear interrupts when cqe off/disable Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 19/37] drm/amd/display: Avoid MPC infinite loop Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 20/37] drm/amd/display: For stereo keep "FLIP_ANY_FRAME" Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 21/37] drm/amd/display: clear optc underflow before turn off odm clock Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 22/37] neigh: fix possible DoS due to net iface start/stop loop Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 23/37] s390/hypfs: avoid error message under KVM Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 24/37] drm/amd/pm: add missing ->fini_microcode interface for Sienna Cichlid Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 25/37] drm/amd/display: Fix pixel clock programming Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 26/37] drm/amdgpu: Increase tlb flush timeout for sriov Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 27/37] netfilter: conntrack: NF_CONNTRACK_PROCFS should no longer default to y Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 28/37] lib/vdso: Mark do_hres_timens() and do_coarse_timens() __always_inline() Greg Kroah-Hartman
2022-09-02 12:19 ` Greg Kroah-Hartman [this message]
2022-09-02 12:19 ` [PATCH 5.10 30/37] io_uring: disable polling pollfree files Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 31/37] xfs: remove infinite loop when reserving free block pool Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 32/37] xfs: always succeed at setting the reserve pool size Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 33/37] xfs: fix overfilling of reserve pool Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 34/37] xfs: fix soft lockup via spinning in filestream ag selection loop Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 35/37] xfs: revert "xfs: actually bump warning counts when we send warnings" Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 36/37] net/af_packet: check len when min_header_len equals to 0 Greg Kroah-Hartman
2022-09-02 12:19 ` [PATCH 5.10 37/37] net: neigh: dont call kfree_skb() under spin_lock_irqsave() Greg Kroah-Hartman
2022-09-02 16:36 ` [PATCH 5.10 00/37] 5.10.141-rc1 review Jon Hunter
2022-09-02 17:36 ` Florian Fainelli
2022-09-02 22:16 ` Shuah Khan
2022-09-03 0:36 ` Guenter Roeck
2022-09-03 3:15 ` Rudi Heitbaum
2022-09-03 6:06 ` Naresh Kamboju
2022-09-03 10:43 ` Sudip Mukherjee
2022-09-05 7:44 ` Pavel Machek
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220902121400.082172669@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=akpm@linux-foundation.org \
--cc=anil.s.keshavamurthy@intel.com \
--cc=ayudutta@amazon.com \
--cc=davem@davemloft.net \
--cc=kuni1840@gmail.com \
--cc=kuniyu@amazon.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mhiramat@kernel.org \
--cc=naveen.n.rao@linux.ibm.com \
--cc=stable@vger.kernel.org \
--cc=wangnan0@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox