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 4.9 31/31] kprobes: dont call disarm_kprobe() for disabled kprobes
Date: Fri, 2 Sep 2022 14:18:57 +0200 [thread overview]
Message-ID: <20220902121357.880910913@linuxfoundation.org> (raw)
In-Reply-To: <20220902121356.732130937@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 | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1616,12 +1616,14 @@ 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))
disarm_kprobe(orig_p, true);
+
orig_p->flags |= KPROBE_FLAG_DISABLED;
}
}
next prev parent reply other threads:[~2022-09-02 12:23 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-02 12:18 [PATCH 4.9 00/31] 4.9.327-rc1 review Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 01/31] parisc: Fix exception handler for fldw and fstw instructions Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 02/31] xfrm: fix refcount leak in __xfrm_policy_check() Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 03/31] af_key: Do not call xfrm_probe_algs in parallel Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 04/31] rose: check NULL rose_loopback_neigh->loopback Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 05/31] bonding: 802.3ad: fix no transmission of LACPDUs Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 06/31] netfilter: nft_payload: report ERANGE for too long offset and length Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 07/31] ratelimit: Fix data-races in ___ratelimit() Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 08/31] net: Fix a data-race around sysctl_tstamp_allow_data Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 09/31] net: Fix a data-race around sysctl_net_busy_poll Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 10/31] net: Fix a data-race around sysctl_net_busy_read Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 11/31] net: Fix a data-race around sysctl_somaxconn Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 12/31] ixgbe: stop resetting SYSTIME in ixgbe_ptp_start_cyclecounter Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 13/31] btrfs: check if root is readonly while setting security xattr Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 14/31] loop: Check for overflow while configuring loop Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 15/31] asm-generic: sections: refactor memory_intersects Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 16/31] mm/hugetlb: fix hugetlb not supporting softdirty tracking Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 17/31] mm: Force TLB flush for PFNMAP mappings before unlink_file_vma() Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 18/31] s390/mm: do not trigger write fault when vma does not allow VM_WRITE Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 19/31] x86/cpu: Add Tiger Lake to Intel family Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 20/31] x86/bugs: Add "unknown" reporting for MMIO Stale Data Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 21/31] kbuild: Fix include path in scripts/Makefile.modpost Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 22/31] Bluetooth: L2CAP: Fix build errors in some archs Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 23/31] media: pvrusb2: fix memory leak in pvr_probe Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 24/31] HID: hidraw: fix memory leak in hidraw_release() Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 25/31] fbdev: fb_pm2fb: Avoid potential divide by zero error Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 26/31] ftrace: Fix NULL pointer dereference in is_ftrace_trampoline when ftrace is dead Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 27/31] arm64: map FDT as RW for early_init_dt_scan() Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 28/31] s390/hypfs: avoid error message under KVM Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 29/31] netfilter: conntrack: NF_CONNTRACK_PROCFS should no longer default to y Greg Kroah-Hartman
2022-09-02 12:18 ` [PATCH 4.9 30/31] mm/rmap: Fix anon_vma->degree ambiguity leading to double-reuse Greg Kroah-Hartman
2022-09-02 12:18 ` Greg Kroah-Hartman [this message]
2022-09-02 16:45 ` [PATCH 4.9 00/31] 4.9.327-rc1 review Florian Fainelli
2022-09-02 22:21 ` Shuah Khan
2022-09-03 0:34 ` Guenter Roeck
2022-09-03 13:16 ` Naresh Kamboju
2022-09-05 7:42 ` Pavel Machek
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