syzbot


KASAN: slab-out-of-bounds Write in xfs_inodegc_worker

Status: moderation: reported on 2024/05/24 01:33
Subsystems: xfs
[Documentation on labels]
Reported-by: syzbot+976025a936e221db2165@syzkaller.appspotmail.com
First crash: 27d, last: 5d03h

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in instrument_atomic_write include/linux/instrumented.h:82 [inline]
BUG: KASAN: slab-out-of-bounds in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
BUG: KASAN: slab-out-of-bounds in cpumask_clear_cpu include/linux/cpumask.h:538 [inline]
BUG: KASAN: slab-out-of-bounds in xfs_inodegc_worker+0xbf/0x7f0 fs/xfs/xfs_icache.c:1863
Write of size 8 at addr ffff888059ed4eb8 by task kworker/3:2/1268

CPU: 3 PID: 1268 Comm: kworker/3:2 Not tainted 6.10.0-rc3-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: xfs-inodegc/loop3 xfs_inodegc_worker
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
 instrument_atomic_write include/linux/instrumented.h:82 [inline]
 clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
 cpumask_clear_cpu include/linux/cpumask.h:538 [inline]
 xfs_inodegc_worker+0xbf/0x7f0 fs/xfs/xfs_icache.c:1863
 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 6520:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
 kmalloc_noprof include/linux/slab.h:660 [inline]
 kzalloc_noprof include/linux/slab.h:778 [inline]
 xfs_init_fs_context+0x45/0x550 fs/xfs/xfs_super.c:2007
 alloc_fs_context+0x54a/0x9c0 fs/fs_context.c:318
 do_new_mount fs/namespace.c:3331 [inline]
 path_mount+0xbfb/0x1f10 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount fs/namespace.c:3875 [inline]
 __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

The buggy address belongs to the object at ffff888059ed4000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 56 bytes to the right of
 allocated 3712-byte region [ffff888059ed4000, ffff888059ed4e80)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x59ed0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff)
page_type: 0xffffefff(slab)
raw: 04fff00000000040 ffff888015443040 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000040004 00000001ffffefff 0000000000000000
head: 04fff00000000040 ffff888015443040 dead000000000100 dead000000000122
head: 0000000000000000 0000000000040004 00000001ffffefff 0000000000000000
head: 04fff00000000003 ffffea000167b401 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4695, tgid 4695 (udevd), ts 51952070224, free_ts 51436783823
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1468
 prep_new_page mm/page_alloc.c:1476 [inline]
 get_page_from_freelist+0x136a/0x2e50 mm/page_alloc.c:3420
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4678
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x56/0x110 mm/slub.c:2265
 allocate_slab mm/slub.c:2428 [inline]
 new_slab+0x84/0x260 mm/slub.c:2481
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3667
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3757
 __slab_alloc_node mm/slub.c:3810 [inline]
 slab_alloc_node mm/slub.c:3989 [inline]
 __do_kmalloc_node mm/slub.c:4121 [inline]
 __kmalloc_noprof+0x37f/0x420 mm/slub.c:4135
 kmalloc_noprof include/linux/slab.h:664 [inline]
 tomoyo_realpath_from_path+0xbf/0x710 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x2a7/0x3b0 security/tomoyo/file.c:771
 tomoyo_file_open+0x71/0x90 security/tomoyo/tomoyo.c:334
 security_file_open+0x78/0x8b0 security/security.c:2962
 do_dentry_open+0x5ca/0x1930 fs/open.c:942
 do_open fs/namei.c:3650 [inline]
 path_openat+0x1e3a/0x29f0 fs/namei.c:3807
 do_filp_open+0x1dc/0x430 fs/namei.c:3834
 do_sys_openat2+0x17a/0x1e0 fs/open.c:1405
page last free pid 5304 tgid 5304 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1088 [inline]
 free_unref_page+0x64a/0xe40 mm/page_alloc.c:2583
 __put_partials+0x14c/0x170 mm/slub.c:2995
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3941 [inline]
 slab_alloc_node mm/slub.c:4001 [inline]
 kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4008
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139
 getname_flags+0x9b/0xf0 include/linux/audit.h:322
 vfs_fstatat+0x9a/0x150 fs/stat.c:303
 __do_sys_newfstatat+0xa6/0x130 fs/stat.c:468
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888059ed4d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888059ed4e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888059ed4e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                        ^
 ffff888059ed4f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888059ed4f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/11 14:08 upstream 83a7eefedc9b c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-out-of-bounds Write in xfs_inodegc_worker
2024/05/20 01:23 upstream eb6a9339efeb c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-out-of-bounds Write in xfs_inodegc_worker
* Struck through repros no longer work on HEAD.