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

Status: auto-obsoleted due to no activity on 2025/03/11 21:03
Reported-by: syzbot+c72d8f10e58e460e5871@syzkaller.appspotmail.com
First crash: 534d, last: 534d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: slab-out-of-bounds Read in nilfs_iget_test (2) 17 2 512d 602d 0/3 auto-obsoleted due to no activity on 2025/04/02 20:58
linux-6.1 KASAN: slab-out-of-bounds Read in nilfs_iget_test 17 1 1028d 1028d 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 955d 996d 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 56d 56d 0/3 upstream: reported on 2026/03/25 09:07
upstream KASAN: slab-out-of-bounds Read in nilfs_iget_test nilfs 19 21 1121d 1324d 0/29 auto-obsoleted due to no activity on 2023/08/22 15:25

Sample crash report:
loop2: detected capacity change from 0 to 4096
NILFS (loop2): invalid segment: Checksum error in segment payload
NILFS (loop2): trying rollback from an earlier position
==================================================================
BUG: KASAN: slab-out-of-bounds in nilfs_iget_test+0xa1/0x320 fs/nilfs2/inode.c:544
Read of size 8 at addr ffff888071c9e198 by task syz.2.3570/19868

CPU: 1 PID: 19868 Comm: syz.2.3570 Not tainted 6.1.119-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+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 nilfs_iget_test+0xa1/0x320 fs/nilfs2/inode.c:544
 find_inode+0x16b/0x430 fs/inode.c:956
 ilookup5_nowait fs/inode.c:1511 [inline]
 ilookup5+0x9d/0x200 fs/inode.c:1540
 iget5_locked+0x33/0x270 fs/inode.c:1321
 nilfs_iget_locked+0x127/0x180 fs/nilfs2/inode.c:605
 nilfs_dat_read+0xbb/0x300 fs/nilfs2/dat.c:508
 nilfs_load_super_root fs/nilfs2/the_nilfs.c:120 [inline]
 load_nilfs+0x4f1/0x1040 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:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3056
 do_mount fs/namespace.c:3399 [inline]
 __do_sys_mount fs/namespace.c:3607 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3584
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f96f5f81fea
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:00007f96f6dc5e88 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f96f6dc5f10 RCX: 00007f96f5f81fea
RDX: 0000000020000dc0 RSI: 0000000020000400 RDI: 00007f96f6dc5ed0
RBP: 0000000020000dc0 R08: 00007f96f6dc5f10 R09: 0000000000000090
R10: 0000000000000090 R11: 0000000000000246 R12: 0000000020000400
R13: 00007f96f6dc5ed0 R14: 0000000000000d9c R15: 0000000020003280
 </TASK>

Allocated by task 19162:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc_lru+0x10c/0x2d0 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 f2fs_alloc_inode+0x171/0x540 fs/f2fs/super.c:1419
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x61/0x1d0 fs/inode.c:1059
 new_inode+0x25/0x1d0 fs/inode.c:1087
 f2fs_new_inode+0x11d/0x1020 fs/f2fs/namei.c:191
 f2fs_mkdir+0x123/0x520 fs/f2fs/namei.c:691
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4106
 do_mkdirat+0x225/0x360 fs/namei.c:4131
 __do_sys_mkdirat fs/namei.c:4146 [inline]
 __se_sys_mkdirat fs/namei.c:4144 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4144
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845
 destroy_inode fs/inode.c:316 [inline]
 evict+0x87d/0x930 fs/inode.c:716
 dispose_list fs/inode.c:734 [inline]
 evict_inodes+0x668/0x700 fs/inode.c:788
 generic_shutdown_super+0x94/0x340 fs/super.c:480
 kill_block_super+0x7a/0xe0 fs/super.c:1470
 kill_f2fs_super+0x2ff/0x3c0 fs/f2fs/super.c:4674
 deactivate_locked_super+0xa0/0x110 fs/super.c:332
 cleanup_mnt+0x490/0x520 fs/namespace.c:1186
 task_work_run+0x246/0x300 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845
 destroy_inode fs/inode.c:316 [inline]
 evict+0x87d/0x930 fs/inode.c:716
 dispose_list fs/inode.c:734 [inline]
 evict_inodes+0x668/0x700 fs/inode.c:788
 generic_shutdown_super+0x94/0x340 fs/super.c:480
 kill_block_super+0x7a/0xe0 fs/super.c:1470
 kill_f2fs_super+0x2ff/0x3c0 fs/f2fs/super.c:4674
 deactivate_locked_super+0xa0/0x110 fs/super.c:332
 cleanup_mnt+0x490/0x520 fs/namespace.c:1186
 task_work_run+0x246/0x300 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff888071c9d8c0
 which belongs to the cache f2fs_inode_cache of size 2144
The buggy address is located 120 bytes to the right of
 2144-byte region [ffff888071c9d8c0, ffff888071c9e120)

The buggy address belongs to the physical page:
page:ffffea0001c72600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888071c9ea80 pfn:0x71c98
head:ffffea0001c72600 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88807e1fc401
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001565e00 dead000000000003 ffff888142397dc0
raw: ffff888071c9ea80 00000000800e0002 00000001ffffffff ffff88807e1fc401
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 4583, tgid 4582 (syz.1.52), ts 116240053081, free_ts 114199116130
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4313
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5590
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc_lru+0x1a5/0x2d0 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 f2fs_alloc_inode+0x171/0x540 fs/f2fs/super.c:1419
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x1c8/0x830 fs/inode.c:1369
 f2fs_iget+0x52/0x47b0 fs/f2fs/inode.c:483
 f2fs_fill_super+0x4a4b/0x7c40 fs/f2fs/super.c:4293
 mount_bdev+0x2c9/0x3f0 fs/super.c:1443
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3056
 do_mount fs/namespace.c:3399 [inline]
 __do_sys_mount fs/namespace.c:3607 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3584
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 alloc_pid+0x9c/0xc50 kernel/pid.c:180
 copy_process+0x1ec7/0x4060 kernel/fork.c:2282
 kernel_clone+0x222/0x920 kernel/fork.c:2681
 kernel_thread+0x152/0x1d0 kernel/fork.c:2741
 create_kthread kernel/kthread.c:399 [inline]
 kthreadd+0x596/0x760 kernel/kthread.c:748
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff888071c9e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888071c9e100: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888071c9e180: fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00
                            ^
 ffff888071c9e200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888071c9e280: 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
2024/12/01 21:02 linux-6.1.y e4d90d63d385 68914665 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: slab-out-of-bounds Read in nilfs_iget_test
* Struck through repros no longer work on HEAD.