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KCSAN: data-race in handle_mm_fault / loop_configure (2)

Status: auto-closed as invalid on 2022/10/01 14:20
Subsystems: block
[Documentation on labels]
First crash: 606d, last: 606d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in handle_mm_fault / loop_configure block 1 712d 712d 0/26 auto-closed as invalid on 2022/06/18 04:50

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

write to 0xffff888105ef73e0 of 4 bytes by task 7630 on cpu 1:
 mapping_set_gfp_mask include/linux/pagemap.h:290 [inline]
 loop_configure+0x7f5/0xc30 drivers/block/loop.c:1077
 lo_ioctl+0x641/0x1290
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:614
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:856
 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 0xffff888105ef73e0 of 4 bytes by task 7633 on cpu 0:
 mapping_gfp_mask include/linux/pagemap.h:274 [inline]
 __get_fault_gfp_mask mm/memory.c:2944 [inline]
 __handle_mm_fault mm/memory.c:4970 [inline]
 handle_mm_fault+0x24e/0xa90 mm/memory.c:5151
 do_user_addr_fault+0x4a1/0x980 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1488 [inline]
 exc_page_fault+0x60/0x160 arch/x86/mm/fault.c:1544
 asm_exc_page_fault+0x22/0x30

value changed: 0x00100cca -> 0x00100c0a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7633 Comm: syz-executor.5 Not tainted 6.0.0-rc2-syzkaller-00248-ge022620b5d05-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/08/27 14:12 upstream e022620b5d05 07177916 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in handle_mm_fault / loop_configure
* Struck through repros no longer work on HEAD.