syzbot


KASAN: use-after-free Read in nilfs_permission

Status: closed as dup on 2022/10/11 10:33
Subsystems: nilfs
[Documentation on labels]
Reported-by: syzbot+983470d8253700fc9461@syzkaller.appspotmail.com
First crash: 616d, last: 602d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: use-after-free Read in nilfs_segctor_confirm nilfs C inconclusive 19 603d 621d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] KASAN: use-after-free Read in nilfs_permission 1 (2) 2022/10/06 13:44

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in nilfs_permission+0x65/0xb0 fs/nilfs2/inode.c:980
Read of size 8 at addr ffff88802183bc00 by task syz-executor.0/9869

CPU: 0 PID: 9869 Comm: syz-executor.0 Not tainted 6.0.0-syzkaller-09423-g493ffd6605b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 print_address_description+0x65/0x4b0 mm/kasan/report.c:317
 print_report+0x108/0x1f0 mm/kasan/report.c:433
 kasan_report+0xc3/0xf0 mm/kasan/report.c:495
 nilfs_permission+0x65/0xb0 fs/nilfs2/inode.c:980
 do_inode_permission fs/namei.c:458 [inline]
 inode_permission+0x22c/0x450 fs/namei.c:525
 may_o_create fs/namei.c:3242 [inline]
 lookup_open fs/namei.c:3376 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0xcea/0x2df0 fs/namei.c:3688
 do_filp_open+0x264/0x4f0 fs/namei.c:3718
 do_sys_openat2+0x124/0x4e0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_open fs/open.c:1334 [inline]
 __se_sys_open fs/open.c:1330 [inline]
 __x64_sys_open+0x221/0x270 fs/open.c:1330
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f0c9ea8b5a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0c9fc8e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f0c9ebac050 RCX: 00007f0c9ea8b5a9
RDX: 0000000000000000 RSI: 000000000014da42 RDI: 00000000200000c0
RBP: 00007f0c9eae6580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc03c5a44f R14: 00007f0c9fc8e300 R15: 0000000000022000
 </TASK>

Allocated by task 9860:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:437 [inline]
 ____kasan_kmalloc+0xcd/0x100 mm/kasan/common.c:516
 kasan_kmalloc include/linux/kasan.h:234 [inline]
 kmem_cache_alloc_trace+0x97/0x310 mm/slub.c:3289
 kmalloc include/linux/slab.h:600 [inline]
 kzalloc include/linux/slab.h:733 [inline]
 nilfs_find_or_create_root+0x142/0x4f0 fs/nilfs2/the_nilfs.c:747
 nilfs_attach_checkpoint+0xcd/0x4a0 fs/nilfs2/super.c:519
 nilfs_fill_super+0x2e8/0x5d0 fs/nilfs2/super.c:1064
 nilfs_mount+0x613/0x9b0 fs/nilfs2/super.c:1317
 legacy_get_tree+0xea/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x289/0xad0 fs/namespace.c:3040
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x2d3/0x3c0 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 9860:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x3d/0x60 mm/kasan/common.c:45
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:367
 kasan_slab_free include/linux/kasan.h:200 [inline]
 slab_free_hook mm/slub.c:1759 [inline]
 slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1785
 slab_free mm/slub.c:3539 [inline]
 kfree+0xda/0x210 mm/slub.c:4567
 nilfs_evict_inode+0x253/0x3d0 fs/nilfs2/inode.c:924
 evict+0x2a4/0x620 fs/inode.c:664
 nilfs_new_inode+0x6b8/0x8a0
 nilfs_create+0xdc/0x2d0 fs/nilfs2/namei.c:85
 lookup_open fs/namei.c:3413 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x12d0/0x2df0 fs/namei.c:3688
 do_filp_open+0x264/0x4f0 fs/namei.c:3718
 do_sys_openat2+0x124/0x4e0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_creat fs/open.c:1402 [inline]
 __se_sys_creat fs/open.c:1396 [inline]
 __x64_sys_creat+0x11f/0x160 fs/open.c:1396
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88802183bc00
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 0 bytes inside of
 256-byte region [ffff88802183bc00, ffff88802183bd00)

The buggy address belongs to the physical page:
page:ffffea0000860e80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2183a
head:ffffea0000860e80 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea00009f8000 dead000000000003 ffff888012041b40
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 3838, tgid 3838 (syz-executor.5), ts 118999659806, free_ts 118948212369
 prep_new_page mm/page_alloc.c:2532 [inline]
 get_page_from_freelist+0x742/0x7c0 mm/page_alloc.c:4283
 __alloc_pages+0x259/0x560 mm/page_alloc.c:5549
 __alloc_pages_node include/linux/gfp.h:243 [inline]
 alloc_slab_page+0x2e/0xf0 mm/slub.c:1831
 allocate_slab+0x5e/0x520 mm/slub.c:1974
 new_slab mm/slub.c:2034 [inline]
 ___slab_alloc+0x3ee/0xc40 mm/slub.c:3036
 __slab_alloc mm/slub.c:3123 [inline]
 slab_alloc_node mm/slub.c:3214 [inline]
 __kmalloc_node+0x2cd/0x420 mm/slub.c:4473
 kmalloc_array_node include/linux/slab.h:695 [inline]
 kcalloc_node include/linux/slab.h:700 [inline]
 memcg_alloc_slab_cgroups+0x7c/0x120 mm/memcontrol.c:2831
 account_slab mm/slab.h:630 [inline]
 allocate_slab+0xa6/0x520 mm/slub.c:1990
 new_slab mm/slub.c:2034 [inline]
 ___slab_alloc+0x3ee/0xc40 mm/slub.c:3036
 __slab_alloc mm/slub.c:3123 [inline]
 slab_alloc_node mm/slub.c:3214 [inline]
 slab_alloc mm/slub.c:3256 [inline]
 kmem_cache_alloc_trace+0x25f/0x310 mm/slub.c:3287
 kmalloc include/linux/slab.h:600 [inline]
 kzalloc include/linux/slab.h:733 [inline]
 get_undo_list ipc/sem.c:1856 [inline]
 copy_semundo+0xb2/0x230 ipc/sem.c:2313
 copy_process+0x180f/0x4000 kernel/fork.c:2240
 kernel_clone+0x21f/0x790 kernel/fork.c:2673
 __do_sys_clone kernel/fork.c:2807 [inline]
 __se_sys_clone kernel/fork.c:2791 [inline]
 __x64_sys_clone+0x228/0x290 kernel/fork.c:2791
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1449 [inline]
 free_pcp_prepare+0x812/0x900 mm/page_alloc.c:1499
 free_unref_page_prepare mm/page_alloc.c:3380 [inline]
 free_unref_page+0x7d/0x5f0 mm/page_alloc.c:3476
 free_slab mm/slub.c:2073 [inline]
 discard_slab mm/slub.c:2079 [inline]
 __unfreeze_partials+0x1ab/0x200 mm/slub.c:2553
 put_cpu_partial+0x106/0x170 mm/slub.c:2629
 qlist_free_all+0x2b/0x70 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x169/0x180 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:447
 kasan_slab_alloc include/linux/kasan.h:224 [inline]
 slab_post_alloc_hook mm/slab.h:727 [inline]
 slab_alloc_node mm/slub.c:3248 [inline]
 slab_alloc mm/slub.c:3256 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3263 [inline]
 kmem_cache_alloc+0x1a6/0x310 mm/slub.c:3273
 getname_flags+0xb8/0x4e0 fs/namei.c:139
 user_path_at_empty+0x2a/0x1a0 fs/namei.c:2875
 do_readlinkat+0x10c/0x3d0 fs/stat.c:468
 __do_sys_readlink fs/stat.c:501 [inline]
 __se_sys_readlink fs/stat.c:498 [inline]
 __x64_sys_readlink+0x7b/0x90 fs/stat.c:498
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff88802183bb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802183bb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802183bc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88802183bc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802183bd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/10/20 18:43 upstream 493ffd6605b2 b31320fc .config console log report info [disk image] [vmlinux] ci2-upstream-fs KASAN: use-after-free Read in nilfs_permission
2022/10/19 17:36 upstream 493ffd6605b2 b31320fc .config console log report info [disk image] [vmlinux] ci2-upstream-fs KASAN: use-after-free Read in nilfs_permission
2022/10/10 01:24 upstream a6afa4199d3d aea5da89 .config console log report info [disk image] [vmlinux] ci2-upstream-fs KASAN: use-after-free Read in nilfs_permission
2022/10/06 11:13 upstream 2bca25eaeba6 2c6543ad .config console log report info [disk image] [vmlinux] ci2-upstream-fs KASAN: use-after-free Read in nilfs_permission
* Struck through repros no longer work on HEAD.