syzbot


KCSAN: data-race in mas_replace / mas_state_walk

Status: auto-obsoleted due to no activity on 2023/07/31 17:30
Subsystems: mm
[Documentation on labels]
First crash: 836d, last: 787d

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

write to 0xffff888104ae9100 of 8 bytes by task 7659 on cpu 0:
 mte_set_node_dead lib/maple_tree.c:303 [inline]
 mas_replace+0x5af/0x890 lib/maple_tree.c:1787
 mas_commit_b_node lib/maple_tree.c:3652 [inline]
 mas_wr_bnode lib/maple_tree.c:4358 [inline]
 mas_wr_modify+0x2b28/0x39e0 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 mm/internal.h:1070 [inline]
 vma_expand+0x2e7/0x340 mm/mmap.c:710
 mmap_region+0x7b6/0x1490 mm/mmap.c:2617
 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 0xffff888104ae9100 of 8 bytes by task 7677 on cpu 1:
 ma_dead_node lib/maple_tree.c:546 [inline]
 mtree_range_walk lib/maple_tree.c:2978 [inline]
 mas_state_walk+0x43d/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: 0xffff888104cb0c06 -> 0xffff888104ae9100

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7677 Comm: syz-executor.2 Not tainted 6.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
==================================================================

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/26 17:21 upstream 6995e2de6891 4cd5bb25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/06/15 22:11 upstream b6dad5178cea f3921d4d .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/06/14 07:48 upstream 15adb51c04cc d2ee9228 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/06/09 08:38 upstream 25041a4c02c7 058b3a5a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/06/06 01:35 upstream f8dba31b0a82 a4ae4f42 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/06/01 05:33 upstream 48b1320a674e babc4389 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/05/31 14:56 upstream afead42fdfca 09898419 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/05/20 19:06 upstream d635f6cc934b 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/05/20 04:08 upstream cbd6ac3837cd 96689200 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/05/16 13:42 upstream f1fcbaa18b28 71b00cfb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/05/11 17:26 upstream d295b66a7b66 0fbd49f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
2023/05/08 12:22 upstream ac9a78681b92 90c93c40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in mas_replace / mas_state_walk
* Struck through repros no longer work on HEAD.