Messages in this thread | ![/](/images/icornerl.gif) | | Date | Sun, 15 Jan 2023 23:31:38 -0800 | Subject | [syzbot] WARNING: refcount bug in mm_update_next_owner | From | syzbot <> |
| |
Hello,
syzbot found the following issue on:
HEAD commit: 0a093b2893c7 Add linux-next specific files for 20230112 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=16a8e102480000 kernel config: https://syzkaller.appspot.com/x/.config?x=835f3591019836d5 dashboard link: https://syzkaller.appspot.com/bug?extid=1d4c86ac0fed92e3fc78 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/8111a570d6cb/disk-0a093b28.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/ecc135b7fc9a/vmlinux-0a093b28.xz kernel image: https://storage.googleapis.com/syzbot-assets/ca8d73b446ea/bzImage-0a093b28.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1d4c86ac0fed92e3fc78@syzkaller.appspotmail.com
------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 0 PID: 5316 at lib/refcount.c:25 refcount_warn_saturate+0x17c/0x1f0 lib/refcount.c:25 Modules linked in: CPU: 0 PID: 5316 Comm: syz-executor.4 Not tainted 6.2.0-rc3-next-20230112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:refcount_warn_saturate+0x17c/0x1f0 lib/refcount.c:25 Code: 0a 31 ff 89 de e8 d4 13 78 fd 84 db 0f 85 2e ff ff ff e8 57 17 78 fd 48 c7 c7 60 87 a6 8a c6 05 e0 ce 54 0a 01 e8 98 a7 b2 05 <0f> 0b e9 0f ff ff ff e8 38 17 78 fd 0f b6 1d ca ce 54 0a 31 ff 89 RSP: 0018:ffffc90005967d80 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff8880829f3a80 RSI: ffffffff8166972c RDI: fffff52000b2cfa2 RBP: ffff888082ae3aa8 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88807e520900 R13: ffff888082ae3fa8 R14: 0000000000000000 R15: ffff888082ae3aa8 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32f23000 CR3: 000000007716c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __refcount_add include/linux/refcount.h:199 [inline] __refcount_inc include/linux/refcount.h:250 [inline] refcount_inc include/linux/refcount.h:267 [inline] get_task_struct include/linux/sched/task.h:110 [inline] mm_update_next_owner+0x585/0x7b0 kernel/exit.c:504 exit_mm kernel/exit.c:562 [inline] do_exit+0x9a4/0x2a90 kernel/exit.c:854 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012 __do_sys_exit_group kernel/exit.c:1023 [inline] __se_sys_exit_group kernel/exit.c:1021 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1021 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f51f5a8c0c9 Code: Unable to access opcode bytes at 0x7f51f5a8c09f. RSP: 002b:00007ffe3c730ad8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000001e RCX: 00007f51f5a8c0c9 RDX: 00007f51f5a3df7b RSI: ffffffffffffffb8 RDI: 0000000000000000 RBP: 0000000000000000 R08: 000000002ed3101e R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffe3c730bc0 </TASK>
--- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
| ![\](/images/icornerr.gif) |