syzbot


KCSAN: data-race in _prb_read_valid / prb_reserve

Status: moderation: reported on 2020/11/09 13:24
Subsystems: ext4 batman
[Documentation on labels]
Reported-by: syzbot+615128043c250cbd858b@syzkaller.appspotmail.com
First crash: 1682d, last: 21h56m

Sample crash report:
loop7: p3 start 18548 is beyond EOD, 
==================================================================
BUG: KCSAN: data-race in _prb_read_valid / prb_reserve

write to 0xffffffff86909b80 of 88 bytes by task 19101 on cpu 0:
 prb_reserve+0x696/0xaf0 kernel/printk/printk_ringbuffer.c:1635
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326
 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2475
 blk_add_partition block/partitions/core.c:540 [inline]
 blk_add_partitions block/partitions/core.c:633 [inline]
 bdev_disk_changed+0x821/0xcb0 block/partitions/core.c:693
 loop_reread_partitions drivers/block/loop.c:436 [inline]
 loop_set_status+0x516/0x5c0 drivers/block/loop.c:1263
 lo_ioctl+0x75b/0x15d0 drivers/block/loop.c:-1
 blkdev_ioctl+0x352/0x440 block/ioctl.c:704
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:892
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:892
 x64_sys_call+0x19a8/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff86909b80 of 8 bytes by task 19108 on cpu 1:
 desc_read kernel/printk/printk_ringbuffer.c:486 [inline]
 prb_first_seq kernel/printk/printk_ringbuffer.c:1957 [inline]
 _prb_read_valid+0x383/0x920 kernel/printk/printk_ringbuffer.c:2114
 prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2185
 __console_flush_and_unlock kernel/printk/printk.c:3304 [inline]
 console_unlock+0x164/0x330 kernel/printk/printk.c:3325
 vprintk_emit+0x388/0x650 kernel/printk/printk.c:2450
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2475
 blk_add_partition block/partitions/core.c:540 [inline]
 blk_add_partitions block/partitions/core.c:633 [inline]
 bdev_disk_changed+0x821/0xcb0 block/partitions/core.c:693
 loop_reread_partitions drivers/block/loop.c:436 [inline]
 loop_set_status+0x516/0x5c0 drivers/block/loop.c:1263
 lo_ioctl+0x75b/0x15d0 drivers/block/loop.c:-1
 blkdev_ioctl+0x352/0x440 block/ioctl.c:704
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:892
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:892
 x64_sys_call+0x19a8/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000000034b8 -> 0x00000000000054b8

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 19108 Comm: syz.7.11695 Not tainted 6.15.0-rc7-syzkaller-00099-g94305e83eccb #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================
truncated

Crashes (3641):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/23 09:54 upstream 94305e83eccb fa44301a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/19 12:06 upstream a5806cd506af b84f0537 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/18 05:54 upstream 5723cc3450bc f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/17 01:52 upstream 3c21441eeffc f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/14 11:32 upstream 9f35e33144ae 7344edeb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/13 16:33 upstream e9565e23cd89 7344edeb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/12 19:07 upstream 82f2b0b97b36 f6671af7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/11 09:05 upstream 3ce9925823c7 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/10 08:59 upstream 0e1329d4045c 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/08 21:10 upstream 2c89c1b655c0 dbf35fa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/02 21:01 upstream 2bfcee565c3a b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/05/02 05:21 upstream ebd297a2affa 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/30 00:04 upstream ca91b9500108 85a5a23f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/28 01:38 upstream b4432656b36e c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/26 23:54 upstream 5bc1018675ec c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/25 07:55 upstream 02ddfb981de8 e3715315 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/25 00:07 upstream e72e9e693307 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/24 13:04 upstream a79be02bba5c 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/23 07:36 upstream bc3372351d0c 53a8b9bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/22 05:58 upstream a33b5a08cbbd 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/21 15:40 upstream 9d7a0577c9db 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/20 19:53 upstream 6fea5fabd332 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/20 07:36 upstream 119009db2674 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/20 00:56 upstream 8560697b23dc 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/19 03:55 upstream 3088d26962e8 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/18 14:34 upstream fc96b232f8e7 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/18 09:33 upstream b5c6891b2c5b 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/17 11:46 upstream cfb2e2c57aef 229db4cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/16 18:47 upstream c62f4b82d571 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/16 07:46 upstream 1a1d569a75f3 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/15 16:34 upstream 834a4a689699 23b969b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/14 07:18 upstream 8ffd015db85f 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/13 17:11 upstream 5aaaedb0cb54 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/13 03:44 upstream 7cdabafc0012 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/12 14:54 upstream 3bde70a2c827 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/12 01:07 upstream e618ee89561b 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/11 08:00 upstream 900241a5cc15 94486846 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/11 00:15 upstream 2eb959eeecc6 1ef3ab4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/09 16:17 upstream a24588245776 47d015b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/08 22:57 upstream bec7dcbc242c a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/08 16:33 upstream 0af2f6be1b42 a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2025/04/07 18:45 upstream 0af2f6be1b42 a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _prb_read_valid / prb_reserve
2021/01/17 12:41 upstream 0da0a8a0a0e1 813be542 .config console log report info ci2-upstream-kcsan-gce
2020/11/09 09:54 upstream f8394f232b1e cba33199 .config console log report info ci2-upstream-kcsan-gce
2020/11/07 20:52 upstream 659caaf65dc9 cba33199 .config console log report info ci2-upstream-kcsan-gce
2020/10/14 17:14 upstream b5fc7a89e58b fc7735a2 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.