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KCSAN: data-race in __anon_vma_prepare / do_wp_page (2)

Status: auto-obsoleted due to no activity on 2023/12/25 00:10
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+c4aac2a661780cb555c1@syzkaller.appspotmail.com
First crash: 109d, last: 109d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __anon_vma_prepare / do_wp_page mm 1 157d 157d 0/26 auto-obsoleted due to no activity on 2023/11/02 18:12

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

write to 0xffff88813aea4460 of 8 bytes by task 5835 on cpu 0:
 __anon_vma_prepare+0x147/0x2b0 mm/rmap.c:214
 anon_vma_prepare include/linux/rmap.h:159 [inline]
 do_anonymous_page mm/memory.c:4169 [inline]
 do_pte_missing mm/memory.c:3728 [inline]
 handle_pte_fault mm/memory.c:5038 [inline]
 __handle_mm_fault mm/memory.c:5179 [inline]
 handle_mm_fault+0x224c/0x2dd0 mm/memory.c:5344
 do_user_addr_fault arch/x86/mm/fault.c:1413 [inline]
 handle_page_fault arch/x86/mm/fault.c:1505 [inline]
 exc_page_fault+0x2f7/0x6c0 arch/x86/mm/fault.c:1561
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

read to 0xffff88813aea4460 of 8 bytes by task 5838 on cpu 1:
 vmf_anon_prepare mm/memory.c:3065 [inline]
 wp_page_copy mm/memory.c:3109 [inline]
 do_wp_page+0x55b/0x1f40 mm/memory.c:3510
 handle_pte_fault mm/memory.c:5054 [inline]
 __handle_mm_fault mm/memory.c:5179 [inline]
 handle_mm_fault+0xe5d/0x2dd0 mm/memory.c:5344
 do_user_addr_fault arch/x86/mm/fault.c:1413 [inline]
 handle_page_fault arch/x86/mm/fault.c:1505 [inline]
 exc_page_fault+0x2f7/0x6c0 arch/x86/mm/fault.c:1561
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

value changed: 0x0000000000000000 -> 0xffff8881339c3c30

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5838 Comm: syz-executor.2 Not tainted 6.7.0-rc1-syzkaller-00019-gc42d9eeef8e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================
loop2: detected capacity change from 0 to 512

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/15 09:55 upstream c42d9eeef8e5 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __anon_vma_prepare / do_wp_page
* Struck through repros no longer work on HEAD.