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

Status: auto-obsoleted due to no activity on 2023/10/02 23:00
Subsystems: mm
[Documentation on labels]
First crash: 518d, last: 518d
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 mm 5 567d 628d 0/28 auto-obsoleted due to no activity on 2023/08/14 12:09

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

write to 0xffff88814f730900 of 8 bytes by task 27592 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:4067
 mas_wr_store_entry+0x748/0x810 lib/maple_tree.c:4382
 mas_store_prealloc+0xe9/0x250 lib/maple_tree.c:5537
 vma_iter_store+0xcb/0xe0 mm/internal.h:1090
 vma_merge+0x7b7/0xeb0 mm/mmap.c:1017
 mprotect_fixup+0x2e0/0x650 mm/mprotect.c:632
 do_mprotect_pkey+0x641/0x920 mm/mprotect.c:818
 __do_sys_mprotect mm/mprotect.c:839 [inline]
 __se_sys_mprotect mm/mprotect.c:836 [inline]
 __x64_sys_mprotect+0x48/0x50 mm/mprotect.c:836
 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 0xffff88814f730900 of 8 bytes by task 27593 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:3869
 mas_walk+0x7e/0x160 lib/maple_tree.c:4988
 lock_vma_under_rcu+0x8d/0x2d0 mm/memory.c:5385
 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: 0xffff88814f73010e -> 0xffff88814f730900

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 27593 Comm: syz-executor.3 Not tainted 6.5.0-syzkaller-00453-g727dbda16b83 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/28 22:51 upstream 727dbda16b83 7ba13a15 .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.