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KCSAN: data-race in _copy_to_iter / fat_set_state (2)

Status: auto-obsoleted due to no activity on 2022/12/15 10:49
Subsystems: exfat
[Documentation on labels]
First crash: 649d, last: 622d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (6) exfat 4 278d 300d 0/27 auto-obsoleted due to no activity on 2023/11/24 07:27
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (5) exfat 1 344d 344d 0/27 auto-obsoleted due to no activity on 2023/09/19 09:04
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (4) exfat 1 401d 401d 0/27 auto-obsoleted due to no activity on 2023/07/24 15:00
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (7) exfat 6 145d 205d 0/27 auto-obsoleted due to no activity on 2024/04/05 03:03
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (8) exfat 2 17d 51d 0/27 moderation: reported on 2024/06/03 14:41
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (3) exfat 1 494d 494d 0/27 auto-obsoleted due to no activity on 2023/04/29 03:39
upstream KCSAN: data-race in _copy_to_iter / fat_set_state exfat 1 720d 720d 0/27 auto-closed as invalid on 2022/09/08 00:15

Sample crash report:
==================================================================
BUG: KCSAN: data-race in _copy_to_iter / fat_set_state

write to 0xffff888118f69025 of 1 bytes by task 29801 on cpu 1:
 fat_set_state+0x16a/0x1d0
 fat_fill_super+0x2238/0x26c0 fs/fat/inode.c:1882
 vfat_fill_super+0x2c/0x40 fs/fat/namei_vfat.c:1200
 mount_bdev+0x1e2/0x280 fs/super.c:1401
 vfat_mount+0x2d/0x40 fs/fat/namei_vfat.c:1207
 legacy_get_tree+0x70/0xc0 fs/fs_context.c:610
 vfs_get_tree+0x49/0x190 fs/super.c:1531
 do_new_mount+0x200/0x650 fs/namespace.c:3040
 path_mount+0x4aa/0xb70 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x281/0x2d0 fs/namespace.c:3568
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888118f69000 of 1024 bytes by task 12107 on cpu 0:
 instrument_copy_to_user include/linux/instrumented.h:120 [inline]
 copyout lib/iov_iter.c:169 [inline]
 _copy_to_iter+0x116/0x8e0 lib/iov_iter.c:527
 copy_page_to_iter+0x333/0x3f0 lib/iov_iter.c:725
 copy_folio_to_iter include/linux/uio.h:169 [inline]
 filemap_read+0x11db/0x1510 mm/filemap.c:2726
 blkdev_read_iter+0x2c6/0x370 block/fops.c:598
 call_read_iter include/linux/fs.h:2185 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x3a5/0x560 fs/read_write.c:470
 ksys_read+0xe8/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12107 Comm: udevd Not tainted 6.1.0-rc4-syzkaller-00020-gf67dd6ce0723-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================
I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2
I/O error, dev loop1, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/10 10:39 upstream f67dd6ce0723 b2488a87 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat_set_state
2022/10/14 13:16 upstream 6d84c258e804 4954e4b2 .config console log report info [disk image] [vmlinux] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat_set_state
* Struck through repros no longer work on HEAD.