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KCSAN: data-race in mas_state_walk / mas_wmb_replace

Status: auto-obsoleted due to no activity on 2023/07/03 09:03
Subsystems: mm
[Documentation on labels]
First crash: 324d, last: 324d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in mas_state_walk / mas_wmb_replace (2) mm 199 99d 132d 0/26 auto-obsoleted due to no activity on 2024/02/06 14:42

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

write to 0xffff888104fff400 of 8 bytes by task 10744 on cpu 1:
 mte_set_parent lib/maple_tree.c:499 [inline]
 mas_adopt_children lib/maple_tree.c:1746 [inline]
 mas_descend_adopt lib/maple_tree.c:2136 [inline]
 mas_wmb_replace+0x8f6/0xfc0 lib/maple_tree.c:2800
 mas_split lib/maple_tree.c:3588 [inline]
 mas_commit_b_node lib/maple_tree.c:3639 [inline]
 mas_wr_bnode lib/maple_tree.c:4358 [inline]
 mas_wr_modify+0x1b89/0x39e0 lib/maple_tree.c:4401
 mas_wr_store_entry+0x701/0x840 lib/maple_tree.c:4439
 mas_store_prealloc+0xe9/0x250 lib/maple_tree.c:5758
 vma_iter_store+0xcb/0xe0 mm/internal.h:1070
 mmap_region+0xcd2/0x1490 mm/mmap.c:2717
 do_mmap+0x67c/0xaa0 mm/mmap.c:1394
 vm_mmap_pgoff+0x12f/0x240 mm/util.c:543
 ksys_mmap_pgoff+0xc5/0x320 mm/mmap.c:1440
 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 0xffff888104fff400 of 8 bytes by task 10745 on cpu 0:
 ma_dead_node lib/maple_tree.c:546 [inline]
 mtree_range_walk lib/maple_tree.c:2955 [inline]
 mas_state_walk+0x267/0x5d0 lib/maple_tree.c:3881
 mas_walk+0x1f/0xd0 lib/maple_tree.c:5109
 lock_vma_under_rcu+0x89/0x290 mm/memory.c:5279
 do_user_addr_fault arch/x86/mm/fault.c:1341 [inline]
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x16e/0x780 arch/x86/mm/fault.c:1590
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

value changed: 0xffff8881048cd60e -> 0xffff888104fff400

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10745 Comm: syz-executor.0 Not tainted 6.4.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
==================================================================
loop0: detected capacity change from 0 to 512
ext4: Unknown parameter 'syz"'

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/29 08:56 upstream 7877cb91f108 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_state_walk / mas_wmb_replace
* Struck through repros no longer work on HEAD.