syzbot


KCSAN: data-race in __anon_vma_prepare / wp_page_copy (3)

Status: auto-closed as invalid on 2022/02/12 08:56
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 325d, last: 325d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __anon_vma_prepare / wp_page_copy (2) 1 448d 448d 0/24 auto-closed as invalid on 2021/10/12 00:20
upstream KCSAN: data-race in __anon_vma_prepare / wp_page_copy 7 484d 581d 0/24 auto-closed as invalid on 2021/09/06 09:04

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

write to 0xffff888100bbf088 of 8 bytes by task 11630 on cpu 1:
 __anon_vma_prepare+0x130/0x2c0 mm/rmap.c:208
 anon_vma_prepare include/linux/rmap.h:149 [inline]
 wp_page_copy+0xa5a/0x10e0 mm/memory.c:2980
 do_wp_page+0x4fb/0xa80
 handle_pte_fault mm/memory.c:4569 [inline]
 __handle_mm_fault mm/memory.c:4686 [inline]
 handle_mm_fault+0x975/0x1590 mm/memory.c:4784
 do_user_addr_fault+0x609/0xbe0 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1485 [inline]
 exc_page_fault+0x91/0x290 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x1e/0x30

read to 0xffff888100bbf088 of 8 bytes by task 11633 on cpu 0:
 anon_vma_prepare include/linux/rmap.h:146 [inline]
 wp_page_copy+0x74/0x10e0 mm/memory.c:2980
 do_wp_page+0x4fb/0xa80
 handle_pte_fault mm/memory.c:4569 [inline]
 __handle_mm_fault mm/memory.c:4686 [inline]
 handle_mm_fault+0x975/0x1590 mm/memory.c:4784
 do_user_addr_fault+0x609/0xbe0 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1485 [inline]
 exc_page_fault+0x91/0x290 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x1e/0x30
 __put_user_nocheck_8+0x3/0x21
 __do_sys_io_setup fs/aio.c:1331 [inline]
 __se_sys_io_setup+0x91/0x1a0 fs/aio.c:1311
 __x64_sys_io_setup+0x2d/0x40 fs/aio.c:1311
 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: 0x0000000000000000 -> 0xffff888102b745f0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11633 Comm: syz-executor.0 Not tainted 5.16.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2022/01/08 08:56 upstream d1587f7bfe9a 2ca0d385 .config log report info KCSAN: data-race in __anon_vma_prepare / wp_page_copy
* Struck through repros no longer work on HEAD.