From: syzbot <syzbot+ec941d6e24f633a59172@syzkaller.appspotmail.com>
To: andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org,
daniel@iogearbox.net, davem@davemloft.net, edumazet@google.com,
jakub@cloudflare.com, john.fastabend@gmail.com, kuba@kernel.org,
linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
pabeni@redhat.com, syzkaller-bugs@googlegroups.com,
xrivendell7@gmail.com
Subject: Re: [syzbot] [net?] [bpf?] possible deadlock in sock_hash_delete_elem (2)
Date: Fri, 26 Apr 2024 23:08:19 -0700 [thread overview]
Message-ID: <000000000000d0b87206170dd88f@google.com> (raw)
In-Reply-To: <0000000000000d7c8f0614076733@google.com>
syzbot has found a reproducer for the following issue on:
HEAD commit: b2ff42c6d3ab Merge tag 'for-netdev' of https://git.kernel...
git tree: bpf
console+strace: https://syzkaller.appspot.com/x/log.txt?x=157ea5e8980000
kernel config: https://syzkaller.appspot.com/x/.config?x=98d5a8e00ed1044a
dashboard link: https://syzkaller.appspot.com/bug?extid=ec941d6e24f633a59172
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=145682f8980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13c06aa0980000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bbdf1d091619/disk-b2ff42c6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4bf7c5b24257/vmlinux-b2ff42c6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/41fcb792fc43/bzImage-b2ff42c6.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ec941d6e24f633a59172@syzkaller.appspotmail.com
============================================
WARNING: possible recursive locking detected
6.9.0-rc5-syzkaller-00171-gb2ff42c6d3ab #0 Not tainted
--------------------------------------------
syz-executor361/5090 is trying to acquire lock:
ffff888022c83260 (&htab->buckets[i].lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff888022c83260 (&htab->buckets[i].lock){+...}-{2:2}, at: sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:945
but task is already holding lock:
ffff88807b2af8f8 (&htab->buckets[i].lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88807b2af8f8 (&htab->buckets[i].lock){+...}-{2:2}, at: sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:945
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&htab->buckets[i].lock);
lock(&htab->buckets[i].lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by syz-executor361/5090:
#0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
#0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: map_delete_elem+0x388/0x5e0 kernel/bpf/syscall.c:1695
#1: ffff88807b2af8f8 (&htab->buckets[i].lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#1: ffff88807b2af8f8 (&htab->buckets[i].lock){+...}-{2:2}, at: sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:945
#2: ffff88801c2a4290 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#2: ffff88801c2a4290 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:145 [inline]
#2: ffff88801c2a4290 (&psock->link_lock){+...}-{2:2}, at: sock_map_unref+0xcc/0x5e0 net/core/sock_map.c:180
#3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
#3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline]
#3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 kernel/trace/bpf_trace.c:2420
stack backtrace:
CPU: 1 PID: 5090 Comm: syz-executor361 Not tainted 6.9.0-rc5-syzkaller-00171-gb2ff42c6d3ab #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
check_deadlock kernel/locking/lockdep.c:3062 [inline]
validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856
__lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:945
bpf_prog_174bfe9d52de9121+0x4f/0x53
bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
__bpf_prog_run include/linux/filter.h:657 [inline]
bpf_prog_run include/linux/filter.h:664 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
bpf_trace_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420
trace_kfree include/trace/events/kmem.h:94 [inline]
kfree+0x2af/0x3a0 mm/slub.c:4377
sk_psock_free_link include/linux/skmsg.h:421 [inline]
sock_map_del_link net/core/sock_map.c:158 [inline]
sock_map_unref+0x3ac/0x5e0 net/core/sock_map.c:180
sock_hash_delete_elem+0x392/0x400 net/core/sock_map.c:949
map_delete_elem+0x464/0x5e0 kernel/bpf/syscall.c:1696
__sys_bpf+0x598/0x810 kernel/bpf/syscall.c:5651
__do_sys_bpf kernel/bpf/syscall.c:5767 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5765 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1dbe94ce29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffff608ae88 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1dbe94ce29
RDX: 0000000000000020 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0
R10: 00000000000000a0 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
next prev parent reply other threads:[~2024-04-27 6:08 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-19 18:11 [syzbot] [bpf?] [net?] possible deadlock in sock_hash_delete_elem (2) syzbot
2024-04-27 6:08 ` syzbot [this message]
2024-04-27 8:15 ` [syzbot] [net?] [bpf?] " Hillf Danton
2024-04-27 8:45 ` syzbot
2024-05-12 6:29 ` Tetsuo Handa
2024-05-12 6:54 ` syzbot
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=000000000000d0b87206170dd88f@google.com \
--to=syzbot+ec941d6e24f633a59172@syzkaller.appspotmail.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=jakub@cloudflare.com \
--cc=john.fastabend@gmail.com \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=syzkaller-bugs@googlegroups.com \
--cc=xrivendell7@gmail.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.