| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <67f11c33.050a0220.0a13.0237.GAE@google.com>
Date: Sat, 05 Apr 2025 05:04:03 -0700
From: syzbot <syzbot+827ae2bfb3a3529333e9@...kaller.appspotmail.com>
To: linux-kernel@...r.kernel.org, richard120310@...il.com,
syzkaller-bugs@...glegroups.com
Subject: Re: [syzbot] [rdma?] [s390?] [net?] KASAN: null-ptr-deref Read in smc_tcp_syn_recv_sock
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
possible deadlock in smc_release
======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc4-syzkaller-00261-g850925a8133c-dirty #0 Not tainted
------------------------------------------------------
syz.1.6963/21920 is trying to acquire lock:
ffff888033c0b750 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: touch_work_lockdep_map kernel/workqueue.c:3895 [inline]
ffff888033c0b750 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: start_flush_work kernel/workqueue.c:4149 [inline]
ffff888033c0b750 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: __flush_work+0x46d/0xc30 kernel/workqueue.c:4181
but task is already holding lock:
ffff88805fe88dd8 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x378/0x5f0 net/smc/af_smc.c:338
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (sk_lock-AF_SMC/1){+.+.}-{0:0}:
lock_sock_nested+0x3a/0xf0 net/core/sock.c:3611
smc_listen_out+0x1fa/0x490 net/smc/af_smc.c:1907
smc_listen_out_connected net/smc/af_smc.c:1927 [inline]
smc_listen_work+0x571/0x50c0 net/smc/af_smc.c:2441
process_one_work+0x9c8/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain kernel/locking/lockdep.c:3904 [inline]
__lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5202
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825
touch_work_lockdep_map kernel/workqueue.c:3895 [inline]
start_flush_work kernel/workqueue.c:4149 [inline]
__flush_work+0x477/0xc30 kernel/workqueue.c:4181
__cancel_work_sync+0x10c/0x130 kernel/workqueue.c:4337
smc_clcsock_release+0x5f/0xe0 net/smc/smc_close.c:29
__smc_release+0x5c2/0x880 net/smc/af_smc.c:303
smc_close_non_accepted+0xda/0x200 net/smc/af_smc.c:1839
smc_close_cleanup_listen net/smc/smc_close.c:45 [inline]
smc_close_active+0xc3c/0x1070 net/smc/smc_close.c:225
__smc_release+0x634/0x880 net/smc/af_smc.c:279
smc_release+0x1fc/0x5f0 net/smc/af_smc.c:346
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(sk_lock-AF_SMC/1);
lock((work_completion)(&new_smc->smc_listen_work));
lock(sk_lock-AF_SMC/1);
lock((work_completion)(&new_smc->smc_listen_work));
*** DEADLOCK ***
3 locks held by syz.1.6963/21920:
#0: ffff8880746ea008 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline]
#0: ffff8880746ea008 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release+0x86/0x270 net/socket.c:657
#1: ffff88805fe88dd8 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x378/0x5f0 net/smc/af_smc.c:338
#2: ffffffff8e1b8380 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#2: ffffffff8e1b8380 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#2: ffffffff8e1b8380 (rcu_read_lock){....}-{1:2}, at: start_flush_work kernel/workqueue.c:4123 [inline]
#2: ffffffff8e1b8380 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x103/0xc30 kernel/workqueue.c:4181
stack backtrace:
CPU: 0 UID: 0 PID: 21920 Comm: syz.1.6963 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_circular_bug+0x41c/0x610 kernel/locking/lockdep.c:2074
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain kernel/locking/lockdep.c:3904 [inline]
__lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5202
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825
touch_work_lockdep_map kernel/workqueue.c:3895 [inline]
start_flush_work kernel/workqueue.c:4149 [inline]
__flush_work+0x477/0xc30 kernel/workqueue.c:4181
__cancel_work_sync+0x10c/0x130 kernel/workqueue.c:4337
smc_clcsock_release+0x5f/0xe0 net/smc/smc_close.c:29
__smc_release+0x5c2/0x880 net/smc/af_smc.c:303
smc_close_non_accepted+0xda/0x200 net/smc/af_smc.c:1839
smc_close_cleanup_listen net/smc/smc_close.c:45 [inline]
smc_close_active+0xc3c/0x1070 net/smc/smc_close.c:225
__smc_release+0x634/0x880 net/smc/af_smc.c:279
smc_release+0x1fc/0x5f0 net/smc/af_smc.c:346
__sock_release+0xb3/0x270 net/socket.c:658
sock_close+0x1c/0x30 net/socket.c:1426
__fput+0x3f9/0xb60 fs/file_table.c:431
task_work_run+0x151/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f851fb7e719
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f85208c6038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f851fd35f80 RCX: 00007f851fb7e719
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000003
RBP: 00007f851fbf132e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f851fd35f80 R15: 00007ffea8200be8
</TASK>
Tested on:
commit: 850925a8 Merge tag '9p-for-6.12-rc5' of https://github..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=114cefb0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=17c0d505695d6b0
dashboard link: https://syzkaller.appspot.com/bug?extid=827ae2bfb3a3529333e9
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=155d294c580000
Powered by blists - more mailing lists