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KCSAN: data-race in ext4_setattr / next_uptodate_page (3)

Status: auto-closed as invalid on 2022/01/14 12:58
Subsystems: ext4
[Documentation on labels]
First crash: 882d, last: 882d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_setattr / next_uptodate_page ext4 5 1089d 1121d 0/26 auto-closed as invalid on 2021/06/20 22:51
upstream KCSAN: data-race in ext4_setattr / next_uptodate_page (2) ext4 1 1049d 1049d 0/26 auto-closed as invalid on 2021/09/03 10:03

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_setattr / next_uptodate_page

write to 0xffff8881371f5268 of 8 bytes by task 9318 on cpu 0:
 i_size_write include/linux/fs.h:913 [inline]
 ext4_setattr+0xd7e/0xf20 fs/ext4/inode.c:5451
 notify_change+0x8a3/0xac0 fs/attr.c:410
 do_truncate fs/open.c:64 [inline]
 do_sys_ftruncate+0x323/0x430 fs/open.c:192
 __do_sys_ftruncate fs/open.c:203 [inline]
 __se_sys_ftruncate fs/open.c:201 [inline]
 __x64_sys_ftruncate+0x2f/0x40 fs/open.c:201
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881371f5268 of 8 bytes by task 9330 on cpu 1:
 i_size_read include/linux/fs.h:891 [inline]
 next_uptodate_page+0x334/0x630 mm/filemap.c:3264
 next_map_page mm/filemap.c:3289 [inline]
 filemap_map_pages+0x531/0x5f0 mm/filemap.c:3345
 do_fault_around mm/memory.c:4143 [inline]
 do_read_fault mm/memory.c:4158 [inline]
 do_fault mm/memory.c:4293 [inline]
 handle_pte_fault mm/memory.c:4551 [inline]
 __handle_mm_fault mm/memory.c:4686 [inline]
 handle_mm_fault+0xaf7/0x1590 mm/memory.c:4784
 faultin_page mm/gup.c:939 [inline]
 __get_user_pages+0x388/0xc80 mm/gup.c:1160
 populate_vma_page_range mm/gup.c:1492 [inline]
 __mm_populate+0x24d/0x370 mm/gup.c:1601
 mm_populate include/linux/mm.h:2734 [inline]
 vm_mmap_pgoff+0x160/0x1f0 mm/util.c:524
 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1623
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x000000000073f000 -> 0x0000000000003f00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9330 Comm: syz-executor.0 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/10 12:51 upstream ded746bfc943 4d4ce9bc .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_setattr / next_uptodate_page
* Struck through repros no longer work on HEAD.