syzbot


KCSAN: data-race in data_push_tail / uuid_string

Status: auto-obsoleted due to no activity on 2023/10/28 05:07
Subsystems: ext4
[Documentation on labels]
First crash: 345d, last: 267d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in data_push_tail / uuid_string (3) ext4 1 58d 58d 0/27 auto-obsoleted due to no activity on 2024/05/24 03:21
upstream KCSAN: data-race in data_push_tail / uuid_string (2) ext4 1 196d 192d 0/27 auto-obsoleted due to no activity on 2024/01/09 18:19

Sample crash report:
loop0: detected capacity change from 0 to 512
EXT4-fs: Quota format mount options ignored when QUOTA feature is enabled
==================================================================
BUG: KCSAN: data-race in data_push_tail / uuid_string

write to 0xffffffff86ec3d80 of 1 bytes by task 5610 on cpu 1:
 string_nocheck lib/vsprintf.c:649 [inline]
 uuid_string+0x435/0x4b0 lib/vsprintf.c:1730
 pointer+0x3ee/0xd10 lib/vsprintf.c:2447
 vsnprintf+0x861/0xe20 lib/vsprintf.c:2822
 va_format lib/vsprintf.c:1682 [inline]
 pointer+0x8a1/0xd10 lib/vsprintf.c:2449
 vsnprintf+0x861/0xe20 lib/vsprintf.c:2822
 vscnprintf+0x42/0x80 lib/vsprintf.c:2924
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2128
 vprintk_store+0x56f/0x800 kernel/printk/printk.c:2242
 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2288
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2322
 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2332
 __ext4_msg+0x18a/0x1a0 fs/ext4/super.c:998
 ext4_fill_super+0x1985/0x3940 fs/ext4/super.c:5718
 get_tree_bdev+0x272/0x300 fs/super.c:1577
 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5735
 vfs_get_tree+0x51/0x1b0 fs/super.c:1750
 do_new_mount+0x203/0x660 fs/namespace.c:3335
 path_mount+0x496/0xb30 fs/namespace.c:3662
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffffff86ec3d80 of 8 bytes by task 5626 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:590 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:675
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1046
 prb_reserve+0x893/0xbc0 kernel/printk/printk_ringbuffer.c:1555
 vprintk_store+0x53e/0x800 kernel/printk/printk.c:2232
 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2288
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2322
 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2332
 __ext4_msg+0x130/0x1a0 fs/ext4/super.c:1000
 ext4_check_opt_consistency+0xaf0/0xb00 fs/ext4/super.c:2841
 __ext4_fill_super fs/ext4/super.c:5263 [inline]
 ext4_fill_super+0x1edb/0x3940 fs/ext4/super.c:5703
 get_tree_bdev+0x272/0x300 fs/super.c:1577
 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5735
 vfs_get_tree+0x51/0x1b0 fs/super.c:1750
 do_new_mount+0x203/0x660 fs/namespace.c:3335
 path_mount+0x496/0xb30 fs/namespace.c:3662
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000100015ece -> 0x302d303030303030

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5626 Comm: syz-executor.0 Not tainted 6.6.0-rc2-syzkaller-00309-g8018e02a8703 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
==================================================================
EXT4-fs (loop0): feature flags set on rev 0 fs, running e2fsck is recommended
EXT4-fs (loop0): orphan cleanup on readonly fs
EXT4-fs warning (device loop0): ext4_enable_quotas:7082: Failed to enable quota tracking (type=0, err=-22, ino=3). Please run e2fsck to fix.
EXT4-fs (loop0): Cannot turn on quotas: error -22
EXT4-fs (loop0): 1 truncate cleaned up
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 ro without journal. Quota mode: writeback.

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/23 05:03 upstream 8018e02a8703 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / uuid_string
2023/09/06 01:34 upstream 7733171926cc 0b6286dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / uuid_string
2023/08/07 17:29 upstream 52a93d39b17d b1b6ae3d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / uuid_string
2023/07/06 19:06 upstream c17414a273b8 1a2f6297 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / uuid_string
* Struck through repros no longer work on HEAD.