syzbot


KCSAN: data-race in _copy_to_iter / fat12_ent_put

Status: auto-obsoleted due to no activity on 2022/10/14 22:33
Subsystems: exfat
[Documentation on labels]
First crash: 654d, last: 624d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in _copy_to_iter / fat12_ent_put (4) exfat 5 363d 393d 0/26 auto-obsoleted due to no activity on 2023/07/02 02:14
upstream KCSAN: data-race in _copy_to_iter / fat12_ent_put (5) exfat 21 184d 169d 0/26 auto-obsoleted due to no activity on 2023/12/28 22:56
upstream KCSAN: data-race in _copy_to_iter / fat12_ent_put (6) exfat 1 86d 86d 0/26 auto-obsoleted due to no activity on 2024/04/04 01:15
upstream KCSAN: data-race in _copy_to_iter / fat12_ent_put (3) exfat 3 437d 453d 0/26 auto-obsoleted due to no activity on 2023/04/24 07:39
upstream KCSAN: data-race in _copy_to_iter / fat12_ent_put (2) exfat 3 553d 587d 0/26 auto-obsoleted due to no activity on 2022/12/31 00:12

Sample crash report:
==================================================================
BUG: KCSAN: data-race in _copy_to_iter / fat12_ent_put

write to 0xffff88812883d20c of 1 bytes by task 14641 on cpu 0:
 fat12_ent_put+0x76/0x180 fs/fat/fatent.c:168
 fat_alloc_clusters+0x47d/0xa80 fs/fat/fatent.c:503
 fat_add_cluster fs/fat/inode.c:108 [inline]
 __fat_get_block fs/fat/inode.c:155 [inline]
 fat_get_block+0x263/0x600 fs/fat/inode.c:190
 __block_write_begin_int+0x33d/0xc70 fs/buffer.c:2006
 __block_write_begin fs/buffer.c:2056 [inline]
 block_write_begin+0x73/0x170 fs/buffer.c:2117
 cont_write_begin+0x3f1/0x520 fs/buffer.c:2471
 fat_write_begin+0x5d/0xe0 fs/fat/inode.c:235
 generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3738
 __generic_file_write_iter+0xe3/0x280 mm/filemap.c:3866
 generic_file_write_iter+0x79/0x1c0 mm/filemap.c:3898
 call_write_iter include/linux/fs.h:2187 [inline]
 aio_write+0x2e0/0x3c0 fs/aio.c:1603
 io_submit_one+0x89b/0x1190 fs/aio.c:2022
 __do_sys_io_submit fs/aio.c:2081 [inline]
 __se_sys_io_submit+0x105/0x280 fs/aio.c:2051
 __x64_sys_io_submit+0x3f/0x50 fs/aio.c:2051
 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 0xffff88812883d000 of 1024 bytes by task 1910 on cpu 1:
 instrument_copy_to_user include/linux/instrumented.h:119 [inline]
 copyout lib/iov_iter.c:169 [inline]
 _copy_to_iter+0x11d/0x8b0 lib/iov_iter.c:524
 copy_page_to_iter+0x333/0x3f0 lib/iov_iter.c:722
 copy_folio_to_iter include/linux/uio.h:169 [inline]
 filemap_read+0x119b/0x1430 mm/filemap.c:2711
 blkdev_read_iter+0x2c6/0x370 block/fops.c:598
 call_read_iter include/linux/fs.h:2181 [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:607
 __do_sys_read fs/read_write.c:617 [inline]
 __se_sys_read fs/read_write.c:615 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:615
 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: 1 PID: 1910 Comm: udevd Not tainted 6.0.0-rc4-syzkaller-00204-g9b4509495418-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
==================================================================

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/09/09 22:32 upstream 9b4509495418 90058bdc .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat12_ent_put
2022/09/01 21:26 upstream 2880e1a175b9 86c46e46 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat12_ent_put
2022/08/26 16:04 upstream 4c612826bec1 e5a303f1 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat12_ent_put
2022/08/23 14:19 upstream 072e51356cd5 cea8b0f7 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat12_ent_put
2022/08/13 14:20 upstream 7ebfc85e2cd7 8dfcaa3d .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat12_ent_put
2022/08/10 03:53 upstream 426b4ca2d6a5 c2a623d6 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat12_ent_put
* Struck through repros no longer work on HEAD.