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KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit (3)

Status: moderation: reported on 2024/02/01 09:39
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+5a6d27fe82de9894417a@syzkaller.appspotmail.com
First crash: 79d, last: 8d02h
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit (2) ext4 20 131d 135d 0/26 auto-obsoleted due to no activity on 2024/01/15 09:22
upstream KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit ext4 9 458d 557d 0/26 auto-obsoleted due to no activity on 2023/04/11 07:35

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit

read-write to 0xffff888237c4f0f0 of 8 bytes by task 15728 on cpu 1:
 instrument_read_write include/linux/instrumented.h:55 [inline]
 __instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:84 [inline]
 ___test_and_clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:114 [inline]
 __test_and_clear_bit_le+0x31/0x60 include/asm-generic/bitops/le.h:61
 ext4_free_inode+0x3f0/0x810 fs/ext4/ialloc.c:316
 ext4_evict_inode+0xb25/0xdd0 fs/ext4/inode.c:303
 evict+0x1ae/0x420 fs/inode.c:667
 iput_final fs/inode.c:1741 [inline]
 iput+0x432/0x5c0 fs/inode.c:1767
 do_unlinkat+0x282/0x4c0 fs/namei.c:4406
 __do_sys_unlink fs/namei.c:4447 [inline]
 __se_sys_unlink fs/namei.c:4445 [inline]
 __x64_sys_unlink+0x30/0x40 fs/namei.c:4445
 x64_sys_call+0x286b/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c4f0f0 of 8 bytes by task 16407 on cpu 0:
 _find_next_zero_bit+0x94/0xf0 lib/find_bit.c:198
 find_next_zero_bit include/linux/find.h:186 [inline]
 find_next_zero_bit_le include/linux/find.h:485 [inline]
 find_inode_bit+0xae/0x320 fs/ext4/ialloc.c:724
 __ext4_new_inode+0xce1/0x2270 fs/ext4/ialloc.c:1064
 ext4_symlink+0x242/0x5a0 fs/ext4/namei.c:3395
 vfs_symlink+0xca/0x1b0 fs/namei.c:4481
 do_symlinkat+0xe3/0x350 fs/namei.c:4507
 __do_sys_symlinkat fs/namei.c:4523 [inline]
 __se_sys_symlinkat fs/namei.c:4520 [inline]
 __x64_sys_symlinkat+0x62/0x70 fs/namei.c:4520
 x64_sys_call+0x2a2d/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:267
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0003ffffffffffff -> 0x0003f7f7ffffffff

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 16407 Comm: syz-executor.4 Not tainted 6.9.0-rc3-syzkaller-00344-g8f2c057754b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/13 06:56 upstream 8f2c057754b2 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/03/25 02:23 upstream 5e74df2f8f15 0ea90952 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/03/24 06:53 upstream 484193fecd2b 0ea90952 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/03/22 15:28 upstream 8e938e398669 4b6cdce6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/03/16 22:11 upstream 66a27abac311 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/03/08 13:44 upstream 3aaa8ce7a335 cf82cde1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/02/29 13:50 upstream 805d849d7c3c 352ab904 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/02/12 02:20 upstream 841c35169323 77b23aa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/02/10 07:23 upstream e6f39a90de92 77b23aa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/02/07 06:51 upstream 99bd3cb0d12e 6404acf9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/02/03 01:18 upstream 021533194476 60bf9982 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
2024/02/01 09:38 upstream 6764c317b6bb 373b66cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __test_and_clear_bit_le / _find_next_zero_bit
* Struck through repros no longer work on HEAD.