syzbot


KCSAN: data-race in truncate_inode_pages_final / xas_store

Status: auto-obsoleted due to no activity on 2024/01/01 23:57
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+b88954a0353baf7b5fe8@syzkaller.appspotmail.com
First crash: 359d, last: 359d

Sample crash report:
EXT4-fs error (device loop2): ext4_do_update_inode:5105: inode #16: comm syz-executor.2: corrupted inode contents
EXT4-fs error (device loop2): ext4_truncate:4192: inode #16: comm syz-executor.2: mark_inode_dirty error
EXT4-fs error (device loop2) in ext4_process_orphan:347: Corrupt filesystem
==================================================================
BUG: KCSAN: data-race in truncate_inode_pages_final / xas_store

write to 0xffff888106dfb050 of 8 bytes by task 29982 on cpu 0:
 xas_delete_node lib/xarray.c:498 [inline]
 update_node lib/xarray.c:759 [inline]
 xas_store+0xc2c/0xc90 lib/xarray.c:844
 page_cache_delete mm/filemap.c:139 [inline]
 __filemap_remove_folio+0x1a8/0x2d0 mm/filemap.c:222
 __remove_mapping+0x341/0x460 mm/vmscan.c:756
 shrink_folio_list+0x16b7/0x2540 mm/vmscan.c:1402
 shrink_inactive_list mm/vmscan.c:1913 [inline]
 shrink_list mm/vmscan.c:2154 [inline]
 shrink_lruvec+0xd80/0x17a0 mm/vmscan.c:5626
 shrink_node_memcgs mm/vmscan.c:5812 [inline]
 shrink_node+0xab3/0x15c0 mm/vmscan.c:5847
 shrink_zones mm/vmscan.c:6086 [inline]
 do_try_to_free_pages+0x43d/0xce0 mm/vmscan.c:6148
 try_to_free_mem_cgroup_pages+0x1e2/0x480 mm/vmscan.c:6463
 try_charge_memcg+0x280/0xd30 mm/memcontrol.c:2742
 obj_cgroup_charge_pages+0xab/0x130 mm/memcontrol.c:3255
 __memcg_kmem_charge_page+0x9c/0x170 mm/memcontrol.c:3281
 __alloc_pages+0x1bb/0x340 mm/page_alloc.c:4585
 alloc_pages_mpol+0xb1/0x1d0 mm/mempolicy.c:2133
 alloc_pages+0xe0/0x100 mm/mempolicy.c:2204
 vm_area_alloc_pages mm/vmalloc.c:3063 [inline]
 __vmalloc_area_node mm/vmalloc.c:3139 [inline]
 __vmalloc_node_range+0x6d2/0xea0 mm/vmalloc.c:3320
 kvmalloc_node+0x121/0x160 mm/util.c:642
 kvmalloc include/linux/slab.h:738 [inline]
 xt_alloc_table_info+0x3d/0x80 net/netfilter/x_tables.c:1192
 do_replace net/ipv4/netfilter/arp_tables.c:970 [inline]
 do_arpt_set_ctl+0x634/0x13b0 net/ipv4/netfilter/arp_tables.c:1421
 nf_setsockopt+0x18d/0x1b0 net/netfilter/nf_sockopt.c:101
 ip_setsockopt+0xe6/0x100 net/ipv4/ip_sockglue.c:1426
 tcp_setsockopt+0x90/0xa0 net/ipv4/tcp.c:3704
 sock_common_setsockopt+0x61/0x70 net/core/sock.c:3711
 do_sock_setsockopt net/socket.c:2311 [inline]
 __sys_setsockopt+0x1d4/0x240 net/socket.c:2334
 __do_sys_setsockopt net/socket.c:2343 [inline]
 __se_sys_setsockopt net/socket.c:2340 [inline]
 __x64_sys_setsockopt+0x66/0x80 net/socket.c:2340
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888106dfb050 of 8 bytes by task 29986 on cpu 1:
 xa_empty include/linux/xarray.h:407 [inline]
 mapping_empty include/linux/pagemap.h:141 [inline]
 truncate_inode_pages_final+0x1d/0x60 mm/truncate.c:472
 ext4_evict_inode+0xb3/0xdc0 fs/ext4/inode.c:182
 evict+0x1aa/0x410 fs/inode.c:666
 iput_final fs/inode.c:1777 [inline]
 iput+0x42c/0x5b0 fs/inode.c:1803
 ext4_process_orphan+0x1a9/0x1c0 fs/ext4/orphan.c:360
 ext4_orphan_cleanup+0x669/0x9b0 fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5591 [inline]
 ext4_fill_super+0x3660/0x39a0 fs/ext4/super.c:5712
 get_tree_bdev+0x272/0x300 fs/super.c:1598
 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5744
 vfs_get_tree+0x51/0x1b0 fs/super.c:1771
 do_new_mount+0x203/0x660 fs/namespace.c:3337
 path_mount+0x496/0xb30 fs/namespace.c:3664
 do_mount fs/namespace.c:3677 [inline]
 __do_sys_mount fs/namespace.c:3886 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3863
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3863
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0xffff88813ad50ffa -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29986 Comm: syz-executor.2 Not tainted 6.7.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================
EXT4-fs (loop2): 1 truncate cleaned up
EXT4-fs (loop2): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
ext4 filesystem being mounted at /root/syzkaller-testdir311063328/syzkaller.l2ZwYG/4188/file1 supports timestamps until 2038-01-19 (0x7fffffff)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/27 23:56 upstream 2cc14f52aeb7 7ec6c044 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in truncate_inode_pages_final / xas_store
* Struck through repros no longer work on HEAD.