syzbot


KASAN: slab-out-of-bounds Read in nilfs_iget_test (2)

Status: upstream: reported on 2024/09/25 00:35
Reported-by: syzbot+568d60a49f536849fa57@syzkaller.appspotmail.com
First crash: 74d, last: 74d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: slab-out-of-bounds Read in nilfs_iget_test 1 500d 500d 0/3 auto-obsoleted due to no activity on 2023/11/04 02:15
linux-5.15 KASAN: slab-out-of-bounds Read in nilfs_iget_test 2 428d 468d 0/3 auto-obsoleted due to no activity on 2024/01/15 12:29
linux-6.1 KASAN: slab-out-of-bounds Read in nilfs_iget_test (2) 1 6d15h 6d15h 0/3 upstream: reported on 2024/12/01 21:03
upstream KASAN: slab-out-of-bounds Read in nilfs_iget_test nilfs 21 593d 796d 0/28 auto-obsoleted due to no activity on 2023/08/22 15:25

Sample crash report:
NILFS (loop2): trying rollback from an earlier position
==================================================================
BUG: KASAN: slab-out-of-bounds in nilfs_iget_test+0xa1/0x320 fs/nilfs2/inode.c:548
Read of size 8 at addr ffff88805f25a5f8 by task syz.2.641/7171

CPU: 1 PID: 7171 Comm: syz.2.641 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 nilfs_iget_test+0xa1/0x320 fs/nilfs2/inode.c:548
 find_inode+0x16b/0x430 fs/inode.c:869
 ilookup5_nowait fs/inode.c:1421 [inline]
 ilookup5+0x9d/0x1f0 fs/inode.c:1450
 iget5_locked+0x33/0x260 fs/inode.c:1231
 nilfs_iget_locked+0x127/0x180 fs/nilfs2/inode.c:609
 nilfs_dat_read+0xbb/0x300 fs/nilfs2/dat.c:497
 nilfs_load_super_root fs/nilfs2/the_nilfs.c:120 [inline]
 load_nilfs+0x3e7/0xe90 fs/nilfs2/the_nilfs.c:301
 nilfs_fill_super+0x2ca/0x660 fs/nilfs2/super.c:1090
 nilfs_mount+0x679/0x9a0 fs/nilfs2/super.c:1347
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1528
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb84824469a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb8466bae68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb8466baef0 RCX: 00007fb84824469a
RDX: 00000000200000c0 RSI: 0000000020000300 RDI: 00007fb8466baeb0
RBP: 00000000200000c0 R08: 00007fb8466baef0 R09: 0000000001014800
R10: 0000000001014800 R11: 0000000000000246 R12: 0000000020000300
R13: 00007fb8466baeb0 R14: 0000000000000da6 R15: 0000000020001a40
 </TASK>

Allocated by task 6078:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 f2fs_kmem_cache_alloc fs/f2fs/f2fs.h:2640 [inline]
 f2fs_alloc_inode+0x15d/0x5b0 fs/f2fs/super.c:1383
 alloc_inode fs/inode.c:236 [inline]
 iget_locked+0x194/0x7f0 fs/inode.c:1279
 f2fs_iget+0x52/0x4b90 fs/f2fs/inode.c:498
 f2fs_fill_super+0x6484/0x8350 fs/f2fs/super.c:4258
 mount_bdev+0x2c9/0x3f0 fs/super.c:1398
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1528
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:3007 [inline]
 call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3087
 destroy_inode fs/inode.c:291 [inline]
 evict+0x87d/0x930 fs/inode.c:637
 f2fs_fill_super+0x6907/0x8350 fs/f2fs/super.c:4441
 mount_bdev+0x2c9/0x3f0 fs/super.c:1398
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1528
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88805f259c80
 which belongs to the cache f2fs_inode_cache of size 2304
The buggy address is located 120 bytes to the right of
 2304-byte region [ffff88805f259c80, ffff88805f25a580)
The buggy address belongs to the page:
page:ffffea00017c9600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805f25e880 pfn:0x5f258
head:ffffea00017c9600 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888029eb3901
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea00017cfc00 0000000400000004 ffff88801ee5d3c0
raw: ffff88805f25e880 00000000800d0001 00000001ffffffff ffff888029eb3901
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 6073, ts 295558572334, free_ts 291636344800
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x18e/0x280 mm/slub.c:3233
 f2fs_kmem_cache_alloc fs/f2fs/f2fs.h:2640 [inline]
 f2fs_alloc_inode+0x15d/0x5b0 fs/f2fs/super.c:1383
 alloc_inode fs/inode.c:236 [inline]
 iget_locked+0x194/0x7f0 fs/inode.c:1279
 f2fs_iget+0x52/0x4b90 fs/f2fs/inode.c:498
 f2fs_fill_super+0x4ef8/0x8350 fs/f2fs/super.c:4150
 mount_bdev+0x2c9/0x3f0 fs/super.c:1398
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1528
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 do_slab_free mm/slub.c:3487 [inline]
 ___cache_free+0xe3/0x100 mm/slub.c:3506
 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 getname_flags+0xb8/0x4e0 fs/namei.c:138
 user_path_at_empty+0x2a/0x180 fs/namei.c:2882
 do_readlinkat+0x114/0x3a0 fs/stat.c:442
 __do_sys_readlink fs/stat.c:475 [inline]
 __se_sys_readlink fs/stat.c:472 [inline]
 __x64_sys_readlink+0x7b/0x90 fs/stat.c:472
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Memory state around the buggy address:
 ffff88805f25a480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805f25a500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805f25a580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                                ^
 ffff88805f25a600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805f25a680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/25 00:34 linux-5.15.y 3a5928702e71 5643e0e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in nilfs_iget_test
* Struck through repros no longer work on HEAD.