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KCSAN: data-race in _copy_to_iter / fat_set_state (6)

Status: auto-obsoleted due to no activity on 2023/11/24 07:27
Subsystems: exfat
[Documentation on labels]
First crash: 220d, last: 198d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (5) exfat 1 264d 264d 0/26 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 321d 321d 0/26 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 66d 125d 0/26 auto-obsoleted due to no activity on 2024/04/05 03:03
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (3) exfat 1 415d 415d 0/26 auto-obsoleted due to no activity on 2023/04/29 03:39
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (2) exfat 2 542d 569d 0/26 auto-obsoleted due to no activity on 2022/12/15 10:49
upstream KCSAN: data-race in _copy_to_iter / fat_set_state exfat 1 641d 641d 0/26 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 0xffff888161fb1025 of 1 bytes by task 3107 on cpu 1:
 fat_set_state+0x16e/0x1d0
 fat_put_super+0x2e/0x80 fs/fat/inode.c:732
 generic_shutdown_super+0xdb/0x210 fs/super.c:693
 kill_block_super+0x2a/0x60 fs/super.c:1646
 deactivate_locked_super+0x73/0x1c0 fs/super.c:481
 deactivate_super+0x9b/0xb0 fs/super.c:514
 cleanup_mnt+0x272/0x2e0 fs/namespace.c:1254
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1261
 task_work_run+0x135/0x1a0 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd6/0xe0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:296
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888161fb1000 of 1024 bytes by task 3143 on cpu 0:
 instrument_copy_to_user include/linux/instrumented.h:113 [inline]
 copyout lib/iov_iter.c:167 [inline]
 _copy_to_iter+0x12b/0x950 lib/iov_iter.c:316
 copy_page_to_iter+0x171/0x2b0 lib/iov_iter.c:481
 copy_folio_to_iter include/linux/uio.h:185 [inline]
 filemap_read+0x424/0x680 mm/filemap.c:2703
 blkdev_read_iter+0x217/0x2c0 block/fops.c:730
 call_read_iter include/linux/fs.h:1950 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x3da/0x5c0 fs/read_write.c:470
 ksys_read+0xeb/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+0x42/0x50 fs/read_write.c:621
 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

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3143 Comm: udevd Not tainted 6.6.0-rc6-syzkaller-00182-gce55c22ec8b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
==================================================================
I/O error, dev loop1, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2
I/O error, dev loop5, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2
I/O error, dev loop5, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/10/20 07:25 upstream ce55c22ec8b2 a42250d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat_set_state
2023/10/17 04:40 upstream 213f891525c2 342b9c55 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat_set_state
2023/09/30 19:01 upstream 9f3ebbef746f 8e26a358 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat_set_state
2023/09/28 19:58 upstream 9ed22ae6be81 d265efd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat_set_state
* Struck through repros no longer work on HEAD.