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KCSAN: data-race in __es_find_extent_range / __es_find_extent_range (4)

Status: auto-obsoleted due to no activity on 2022/12/10 23:58
Subsystems: ext4
[Documentation on labels]
First crash: 509d, last: 509d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __es_find_extent_range / __es_find_extent_range ext4 2 1071d 1076d 0/26 auto-closed as invalid on 2021/05/27 20:25
upstream KCSAN: data-race in __es_find_extent_range / __es_find_extent_range (5) ext4 1 472d 472d 0/26 auto-obsoleted due to no activity on 2023/01/17 15:46
upstream KCSAN: data-race in __es_find_extent_range / __es_find_extent_range (3) ext4 1 864d 864d 0/26 auto-closed as invalid on 2021/12/20 16:23
upstream KCSAN: data-race in __es_find_extent_range / __es_find_extent_range (2) ext4 4 944d 1013d 0/26 auto-closed as invalid on 2021/10/01 16:26
upstream KCSAN: data-race in __es_find_extent_range / __es_find_extent_range (6) ext4 4 349d 339d 22/26 fixed on 2023/07/01 16:05

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

write to 0xffff88810a945d78 of 8 bytes by task 19631 on cpu 0:
 __es_find_extent_range+0x28e/0x330 fs/ext4/extents_status.c:298
 ext4_es_find_extent_range+0x87/0x200 fs/ext4/extents_status.c:320
 ext4_ext_put_gap_in_cache fs/ext4/extents.c:2284 [inline]
 ext4_ext_map_blocks+0x117d/0x1bf0 fs/ext4/extents.c:4192
 ext4_da_map_blocks fs/ext4/inode.c:1783 [inline]
 ext4_da_get_block_prep+0x43a/0x9e0 fs/ext4/inode.c:1860
 __block_write_begin_int+0x33d/0xc50 fs/buffer.c:1991
 __block_write_begin fs/buffer.c:2041 [inline]
 block_page_mkwrite+0x17d/0x310 fs/buffer.c:2510
 ext4_page_mkwrite+0x7c6/0xfa0 fs/ext4/inode.c:6149
 do_page_mkwrite mm/memory.c:2978 [inline]
 do_shared_fault mm/memory.c:4619 [inline]
 do_fault+0x725/0xaf0 mm/memory.c:4687
 handle_pte_fault mm/memory.c:4955 [inline]
 __handle_mm_fault mm/memory.c:5097 [inline]
 handle_mm_fault+0x877/0xa80 mm/memory.c:5218
 faultin_page mm/gup.c:1009 [inline]
 __get_user_pages+0x32a/0xbf0 mm/gup.c:1230
 __get_user_pages_locked mm/gup.c:1434 [inline]
 __get_user_pages_remote+0x431/0x600 mm/gup.c:2187
 pin_user_pages_remote+0x5d/0x90 mm/gup.c:3245
 process_vm_rw_single_vec+0x168/0x440 mm/process_vm_access.c:105
 process_vm_rw_core mm/process_vm_access.c:215 [inline]
 process_vm_rw+0x3e1/0x570 mm/process_vm_access.c:283
 __do_sys_process_vm_writev mm/process_vm_access.c:303 [inline]
 __se_sys_process_vm_writev mm/process_vm_access.c:298 [inline]
 __x64_sys_process_vm_writev+0x76/0x90 mm/process_vm_access.c:298
 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 0xffff88810a945d78 of 8 bytes by task 19615 on cpu 1:
 __es_find_extent_range+0x79/0x330 fs/ext4/extents_status.c:272
 ext4_es_find_extent_range+0x87/0x200 fs/ext4/extents_status.c:320
 ext4_ext_put_gap_in_cache fs/ext4/extents.c:2284 [inline]
 ext4_ext_map_blocks+0x117d/0x1bf0 fs/ext4/extents.c:4192
 ext4_map_blocks+0x296/0x1040 fs/ext4/inode.c:570
 ext4_mpage_readpages+0x6b3/0x11a0 fs/ext4/readpage.c:305
 ext4_readahead+0x99/0xa0 fs/ext4/inode.c:3243
 read_pages+0xa6/0x560 mm/readahead.c:161
 page_cache_ra_unbounded+0x2de/0x320 mm/readahead.c:270
 do_page_cache_ra mm/readahead.c:300 [inline]
 page_cache_ra_order mm/readahead.c:560 [inline]
 ondemand_readahead+0x541/0x6d0 mm/readahead.c:682
 page_cache_async_ra+0x8b/0xa0 mm/readahead.c:731
 do_async_mmap_readahead+0x206/0x240 mm/filemap.c:3071
 filemap_fault+0xf6/0x6a0 mm/filemap.c:3125
 __do_fault mm/memory.c:4203 [inline]
 do_read_fault mm/memory.c:4554 [inline]
 do_fault+0x4e8/0xaf0 mm/memory.c:4683
 handle_pte_fault mm/memory.c:4955 [inline]
 __handle_mm_fault mm/memory.c:5097 [inline]
 handle_mm_fault+0x877/0xa80 mm/memory.c:5218
 do_user_addr_fault+0x4a1/0x980 arch/x86/mm/fault.c:1428
 handle_page_fault arch/x86/mm/fault.c:1519 [inline]
 exc_page_fault+0x60/0x160 arch/x86/mm/fault.c:1575
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
 fault_in_readable+0x115/0x1a0
 fault_in_iov_iter_readable+0x86/0x1b0 lib/iov_iter.c:356
 generic_perform_write+0x116/0x3f0 mm/filemap.c:3743
 ext4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:285
 ext4_file_write_iter+0x2c7/0x1170
 call_write_iter include/linux/fs.h:2191 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x468/0x760 fs/read_write.c:584
 ksys_write+0xe8/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:646
 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

value changed: 0xffff888106315870 -> 0xffff88810269d9d8

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19615 Comm: syz-executor.1 Not tainted 6.1.0-rc3-syzkaller-00288-gb208b9fbbcba-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/05 23:49 upstream b208b9fbbcba 6d752409 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __es_find_extent_range / __es_find_extent_range
* Struck through repros no longer work on HEAD.