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

Status: auto-obsoleted due to no activity on 2025/04/02 20:58
Reported-by: syzbot+568d60a49f536849fa57@syzkaller.appspotmail.com
First crash: 596d, last: 506d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: slab-out-of-bounds Read in nilfs_iget_test 17 1 1022d 1022d 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 17 2 950d 990d 0/3 auto-obsoleted due to no activity on 2024/01/15 12:29
linux-5.15 KASAN: slab-out-of-bounds Read in nilfs_iget_test (3) 17 1 50d 50d 0/3 upstream: reported on 2026/03/25 09:07
linux-6.1 KASAN: slab-out-of-bounds Read in nilfs_iget_test (2) 17 1 528d 528d 0/3 auto-obsoleted due to no activity on 2025/03/11 21:03
upstream KASAN: slab-out-of-bounds Read in nilfs_iget_test nilfs 19 21 1116d 1318d 0/29 auto-obsoleted due to no activity on 2023/08/22 15:25

Sample crash report:
loop1: detected capacity change from 0 to 2048
NILFS (loop1): broken superblock, retrying with spare superblock (blocksize = 1024)
==================================================================
BUG: KASAN: slab-out-of-bounds in nilfs_iget_test+0xa1/0x320 fs/nilfs2/inode.c:548
Read of size 8 at addr ffff888060d638f8 by task syz.1.3380/13545

CPU: 1 PID: 13545 Comm: syz.1.3380 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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:873
 ilookup5_nowait fs/inode.c:1425 [inline]
 ilookup5+0x9d/0x1f0 fs/inode.c:1454
 iget5_locked+0x33/0x260 fs/inode.c:1235
 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:1530
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3012
 do_mount fs/namespace.c:3355 [inline]
 __do_sys_mount fs/namespace.c:3563 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3540
 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: 0033:0x7fad000924ca
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:00007facfdf00e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007facfdf00ef0 RCX: 00007fad000924ca
RDX: 0000000020000180 RSI: 0000000020000a80 RDI: 00007facfdf00eb0
RBP: 0000000020000180 R08: 00007facfdf00ef0 R09: 00000000002080c2
R10: 00000000002080c2 R11: 0000000000000246 R12: 0000000020000a80
R13: 00007facfdf00eb0 R14: 0000000000000a9f R15: 0000000020001340
 </TASK>

Allocated by task 13397:
 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:2642 [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:1283
 f2fs_iget+0x52/0x4b30 fs/f2fs/inode.c:498
 f2fs_nfs_get_inode+0x70/0x100 fs/f2fs/super.c:3089
 generic_fh_to_dentry+0x94/0xe0 fs/libfs.c:1044
 exportfs_decode_fh_raw+0x140/0x590 fs/exportfs/expfs.c:436
 exportfs_decode_fh+0x38/0x70 fs/exportfs/expfs.c:576
 do_handle_to_path fs/fhandle.c:152 [inline]
 handle_to_path fs/fhandle.c:207 [inline]
 do_handle_open+0x44c/0x960 fs/fhandle.c:223
 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

Freed by task 14:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kmem_cache_free+0x91/0x1f0 mm/slub.c:3515
 rcu_do_batch kernel/rcu/tree.c:2523 [inline]
 rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2763
 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925
 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

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
 dispose_list fs/inode.c:655 [inline]
 evict_inodes+0x668/0x700 fs/inode.c:709
 generic_shutdown_super+0x94/0x310 fs/super.c:454
 kill_block_super+0x7a/0xe0 fs/super.c:1427
 kill_f2fs_super+0x2ff/0x3c0 fs/f2fs/super.c:4538
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Second to 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
 dispose_list fs/inode.c:655 [inline]
 evict_inodes+0x668/0x700 fs/inode.c:709
 generic_shutdown_super+0x94/0x310 fs/super.c:454
 kill_block_super+0x7a/0xe0 fs/super.c:1427
 kill_f2fs_super+0x2ff/0x3c0 fs/f2fs/super.c:4538
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff888060d62f80
 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 [ffff888060d62f80, ffff888060d63880)
The buggy address belongs to the page:
page:ffffea0001835800 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888060d65f00 pfn:0x60d60
head:ffffea0001835800 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888020c9e201
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88801f2c1140
raw: ffff888060d65f00 00000000800d000a 00000001ffffffff ffff888020c9e201
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 4510, ts 77939990727, free_ts 73701752219
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5465
 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:2642 [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:1283
 f2fs_iget+0x52/0x4b30 fs/f2fs/inode.c:498
 f2fs_fill_super+0x4f06/0x8350 fs/f2fs/super.c:4151
 mount_bdev+0x2c9/0x3f0 fs/super.c:1400
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3012
 do_mount fs/namespace.c:3355 [inline]
 __do_sys_mount fs/namespace.c:3563 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3540
 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
 free_slab mm/slub.c:2015 [inline]
 discard_slab mm/slub.c:2021 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2507
 put_cpu_partial+0x132/0x1a0 mm/slub.c:2587
 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
 do_sys_openat2+0xd2/0x4f0 fs/open.c:1247
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1280
 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:
 ffff888060d63780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888060d63800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888060d63880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                                ^
 ffff888060d63900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888060d63980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/23 20:57 linux-5.15.y 91786f140358 444551c4 .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
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.