syzbot


KCSAN: data-race in mas_replace_node / mas_state_walk (2)

Status: moderation: reported on 2025/04/29 11:19
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+b737e61fbcac97053f96@syzkaller.appspotmail.com
First crash: 89d, last: 2d01h
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in mas_replace_node / mas_state_walk mm 6 155 565d 597d 0/29 auto-obsoleted due to no activity on 2024/02/06 14:39

Sample crash report:
==================================================================
BUG: KCSAN: data-race in mas_replace_node / mas_state_walk

write to 0xffff888139c0da00 of 8 bytes by task 21686 on cpu 0:
 mte_set_node_dead lib/maple_tree.c:337 [inline]
 mas_put_in_tree lib/maple_tree.c:1736 [inline]
 mas_replace_node+0x1a6/0x410 lib/maple_tree.c:1751
 mas_wr_node_store lib/maple_tree.c:3887 [inline]
 mas_wr_store_entry+0x2406/0x2b50 lib/maple_tree.c:4098
 mas_store_prealloc+0x74d/0x9e0 lib/maple_tree.c:5507
 vma_iter_store_overwrite mm/vma.h:502 [inline]
 vma_iter_store_new+0x1c5/0x200 mm/vma.h:509
 vma_complete+0x125/0x580 mm/vma.c:351
 __split_vma+0x591/0x650 mm/vma.c:565
 split_vma mm/vma.c:595 [inline]
 vma_modify+0x21e/0xc80 mm/vma.c:1618
 vma_modify_flags+0x101/0x130 mm/vma.c:1644
 mprotect_fixup+0x2cc/0x570 mm/mprotect.c:658
 do_mprotect_pkey+0x6d6/0x980 mm/mprotect.c:832
 __do_sys_mprotect mm/mprotect.c:853 [inline]
 __se_sys_mprotect mm/mprotect.c:850 [inline]
 __x64_sys_mprotect+0x48/0x60 mm/mprotect.c:850
 x64_sys_call+0x2794/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:11
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888139c0da00 of 8 bytes by task 21747 on cpu 1:
 ma_dead_node lib/maple_tree.c:575 [inline]
 mtree_range_walk lib/maple_tree.c:2792 [inline]
 mas_state_walk+0x485/0x650 lib/maple_tree.c:3630
 mas_walk+0x30/0x120 lib/maple_tree.c:4936
 lock_vma_under_rcu+0xa2/0x2f0 mm/mmap_lock.c:143
 do_user_addr_fault+0x233/0x1090 arch/x86/mm/fault.c:1327
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0xffff888103d51606 -> 0xffff888139c0da00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 21747 Comm: syz.5.3670 Tainted: G        W           6.16.0-rc7-syzkaller-00105-g2942242dde89 #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================

Crashes (21):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/25 16:49 upstream 2942242dde89 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/07/13 09:04 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/07/10 07:51 upstream 8c2e52ebbe88 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/07/05 11:30 upstream a79a588fc176 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/07/04 05:37 upstream 17bbde2e1716 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/29 14:36 upstream dfba48a70cb6 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/28 10:01 upstream 67a993863163 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/20 17:18 upstream 75f5f23f8787 804b3919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/19 21:05 upstream 24770983ccfe ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/16 03:31 upstream 08215f5486ec 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/13 07:51 upstream 27605c8c0f69 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/12 13:51 upstream 2c4a1f3fe03e 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/09 01:12 upstream 939f15e640f1 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/01 23:55 upstream bb1556ec9464 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/06/01 04:52 upstream 4cb6c8af8591 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/05/31 21:31 upstream 0f70f5b08a47 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/05/18 07:21 upstream 5723cc3450bc f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/05/17 15:13 upstream 172a9d94339c f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/05/06 04:51 upstream 01f95500a162 ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/05/01 07:35 upstream 7a13c14ee59d ce7952f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
2025/04/29 11:19 upstream ca91b9500108 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace_node / mas_state_walk
* Struck through repros no longer work on HEAD.