syzbot


KCSAN: data-race in mas_state_walk / mast_ascend_free

Status: auto-obsoleted due to no activity on 2023/08/14 12:09
Subsystems: mm
[Documentation on labels]
First crash: 629d, last: 567d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in mas_state_walk / mast_ascend_free (2) mm 1 518d 518d 0/28 auto-obsoleted due to no activity on 2023/10/02 23:00

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

write to 0xffff8881a5bb5f00 of 8 bytes by task 4881 on cpu 1:
 mte_set_node_dead lib/maple_tree.c:303 [inline]
 mat_add lib/maple_tree.c:994 [inline]
 mast_ascend_free+0x10d/0x6b0 lib/maple_tree.c:2592
 mas_spanning_rebalance+0x1428/0x3040 lib/maple_tree.c:3075
 mas_wr_spanning_store+0x19ad/0x1db0 lib/maple_tree.c:4066
 mas_wr_store_entry+0x748/0x810 lib/maple_tree.c:4374
 mas_store_prealloc+0xe9/0x250 lib/maple_tree.c:5529
 vma_iter_store+0xcb/0xe0 mm/internal.h:1073
 vma_merge+0x84f/0xc50 mm/mmap.c:1016
 mprotect_fixup+0x2e0/0x650 mm/mprotect.c:631
 do_mprotect_pkey+0x641/0x920 mm/mprotect.c:817
 __do_sys_mprotect mm/mprotect.c:838 [inline]
 __se_sys_mprotect mm/mprotect.c:835 [inline]
 __x64_sys_mprotect+0x48/0x50 mm/mprotect.c:835
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881a5bb5f00 of 8 bytes by task 4924 on cpu 0:
 ma_dead_node lib/maple_tree.c:538 [inline]
 mtree_range_walk lib/maple_tree.c:2954 [inline]
 mas_state_walk+0x267/0x5d0 lib/maple_tree.c:3868
 mas_walk+0x7e/0x160 lib/maple_tree.c:4980
 lock_vma_under_rcu+0x8d/0x2b0 mm/memory.c:5388
 do_user_addr_fault arch/x86/mm/fault.c:1335 [inline]
 handle_page_fault arch/x86/mm/fault.c:1486 [inline]
 exc_page_fault+0x160/0x650 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

value changed: 0xffff8881a5bb590e -> 0xffff8881a5bb5f00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4924 Comm: syz-executor.1 Tainted: G        W          6.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/07/10 12:07 upstream 06c2afb862f9 d47e94ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_state_walk / mast_ascend_free
2023/07/02 03:47 upstream dfab92f27c60 bfc47836 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_state_walk / mast_ascend_free
2023/06/03 14:07 upstream 4ecd704a4c51 a4ae4f42 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in mas_state_walk / mast_ascend_free
2023/05/14 21:42 upstream bb7c241fae62 2b9ba477 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_state_walk / mast_ascend_free
2023/05/10 02:46 upstream 1dc3731daf1f 30aa2a7e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_state_walk / mast_ascend_free
* Struck through repros no longer work on HEAD.