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KCSAN: data-race in filemap_fault / generic_write_end (9)

Status: auto-obsoleted due to no activity on 2023/06/12 19:56
Subsystems: ext4
[Documentation on labels]
First crash: 297d, last: 295d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in filemap_fault / generic_write_end (3) ext4 2 1256d 1257d 0/26 auto-closed as invalid on 2020/10/24 13:06
upstream KCSAN: data-race in filemap_fault / generic_write_end (8) ext4 2 400d 403d 0/26 auto-obsoleted due to no activity on 2023/03/17 09:30
upstream KCSAN: data-race in filemap_fault / generic_write_end (10) exfat 2 115d 78d 0/26 auto-obsoleted due to no activity on 2023/12/25 00:01
upstream KCSAN: data-race in filemap_fault / generic_write_end (4) ext4 3 999d 1082d 0/26 auto-closed as invalid on 2021/07/08 19:40
upstream KCSAN: data-race in filemap_fault / generic_write_end (6) ext4 43 644d 749d 0/26 auto-closed as invalid on 2022/06/28 10:53
upstream KCSAN: data-race in filemap_fault / generic_write_end (7) ext4 1 514d 514d 0/26 auto-obsoleted due to no activity on 2022/11/05 12:50
upstream KCSAN: data-race in filemap_fault / generic_write_end (2) ext4 1 1315d 1315d 0/26 auto-closed as invalid on 2020/08/26 18:57
upstream KCSAN: data-race in filemap_fault / generic_write_end ext4 1 1486d 1425d 0/26 auto-closed as invalid on 2020/04/17 11:16
upstream KCSAN: data-race in filemap_fault / generic_write_end (5) ext4 3 922d 957d 0/26 auto-closed as invalid on 2021/09/23 14:23

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

write to 0xffff888109e18800 of 8 bytes by task 5510 on cpu 1:
 i_size_write include/linux/fs.h:905 [inline]
 generic_write_end+0xb4/0x360 fs/buffer.c:2241
 ext4_da_write_end+0x4df/0x690 fs/ext4/inode.c:3010
 generic_perform_write+0x253/0x3d0 mm/filemap.c:3934
 ext4_buffered_write_iter+0x234/0x3e0 fs/ext4/file.c:289
 ext4_file_write_iter+0xd7/0x10e0
 call_write_iter include/linux/fs.h:1868 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x47b/0x780 fs/read_write.c:584
 ksys_write+0xeb/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+0x42/0x50 fs/read_write.c:646
 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

read to 0xffff888109e18800 of 8 bytes by task 5520 on cpu 0:
 i_size_read include/linux/fs.h:883 [inline]
 filemap_fault+0x94/0xb70 mm/filemap.c:3255
 __do_fault mm/memory.c:4176 [inline]
 do_cow_fault mm/memory.c:4560 [inline]
 do_fault mm/memory.c:4661 [inline]
 do_pte_missing mm/memory.c:3647 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault mm/memory.c:5089 [inline]
 handle_mm_fault+0x1b38/0x2c60 mm/memory.c:5243
 faultin_page mm/gup.c:925 [inline]
 __get_user_pages+0x363/0xc30 mm/gup.c:1147
 populate_vma_page_range mm/gup.c:1543 [inline]
 __mm_populate+0x23d/0x370 mm/gup.c:1652
 mm_populate include/linux/mm.h:3153 [inline]
 vm_mmap_pgoff+0x1a3/0x240 mm/util.c:548
 ksys_mmap_pgoff+0x2ac/0x320 mm/mmap.c:1440
 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

value changed: 0x0000000000fdb000 -> 0x0000000000fdc000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5520 Comm: syz-executor.5 Not tainted 6.4.0-rc1-syzkaller-00001-gba0ad6ed89fd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/08 19:53 upstream ba0ad6ed89fd c7a5e2a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in filemap_fault / generic_write_end
2023/05/07 02:48 upstream fc4354c6e5c2 90c93c40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in filemap_fault / generic_write_end
2023/05/06 09:55 upstream 2e1e1337881b de870ca5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in filemap_fault / generic_write_end
* Struck through repros no longer work on HEAD.