syzbot


KCSAN: data-race in data_alloc / data_push_tail (3)

Status: moderation: reported on 2024/09/08 06:11
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+faa791a3223590f7f155@syzkaller.appspotmail.com
First crash: 201d, last: 3d15h
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in data_alloc / data_push_tail (2) batman 44 247d 390d 0/28 auto-obsoleted due to no activity on 2024/08/28 06:32
upstream KCSAN: data-race in data_alloc / data_push_tail ext4 94 701d 1164d 0/28 auto-obsoleted due to no activity on 2023/05/31 17:30

Sample crash report:
program syz.2.10591 is using a deprecated SCSI ioctl, please convert it to SG_IO
==================================================================
BUG: KCSAN: data-race in data_alloc / data_push_tail

write to 0xffffffff88bf0af0 of 8 bytes by task 29 on cpu 1:
 data_alloc+0x216/0x2c0 kernel/printk/printk_ringbuffer.c:1082
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326
 vprintk_emit+0x168/0x690 kernel/printk/printk.c:2408
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x7a/0xa0 kernel/printk/printk.c:2457
 kauditd_printk_skb kernel/audit.c:546 [inline]
 kauditd_hold_skb+0x1a3/0x1b0 kernel/audit.c:581
 kauditd_send_queue+0x288/0x2e0 kernel/audit.c:766
 kauditd_thread+0x42a/0x650 kernel/audit.c:890
 kthread+0x4ae/0x520 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffffffff88bf0af0 of 8 bytes by task 27596 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:679
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1054
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326
 vprintk_emit+0x168/0x690 kernel/printk/printk.c:2408
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x7a/0xa0 kernel/printk/printk.c:2457
 scsi_ioctl+0x452/0x1540 drivers/scsi/scsi_ioctl.c:896
 sg_ioctl_common drivers/scsi/sg.c:1102 [inline]
 sg_ioctl+0xda4/0x1870 drivers/scsi/sg.c:1156
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xc9/0x140 fs/ioctl.c:892
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:892
 x64_sys_call+0x1690/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000fffff1b1 -> 0x00000000fffffca1

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 27596 Comm: syz.2.10591 Tainted: G        W          6.14.0-syzkaller #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================

Crashes (21):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/24 15:45 upstream 38fec10eb60d 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/03/20 03:04 upstream a7f2e10ecd8f e20d7b13 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/03/13 15:04 upstream b7f94fcf5546 44be8b44 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/03/08 04:59 upstream 21e4543a2e2f 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/03/06 15:50 upstream 848e07631744 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/03/02 10:46 upstream ece144f151ac c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/02/28 19:25 upstream 76544811c850 67cf5345 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/02/25 20:55 upstream 2a1944bff549 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/02/20 08:30 upstream 87a132e73910 50668798 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/02/12 23:24 upstream 4dc1d1bec898 b27c2402 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/02/06 19:11 upstream 92514ef226f5 8002dd28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/01/08 08:35 upstream 09a0fa92e5b4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/01/06 00:32 upstream 9244696b34f2 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2025/01/03 10:02 upstream 0bc21e701a6f d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2024/12/21 04:03 upstream e9b8ffafd20a d7f584ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2024/12/07 14:13 upstream b5f217084ab3 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2024/10/31 20:58 upstream 0fc810ae3ae1 96eb609f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2024/09/30 07:01 upstream 9852d85ec9d4 ba29ff75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2024/09/19 04:05 upstream 4a39ac5b7d62 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2024/09/17 10:28 upstream a430d95c5efa c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
2024/09/08 06:10 upstream d1f2d51b711a 9750182a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_alloc / data_push_tail
* Struck through repros no longer work on HEAD.