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KASAN: slab-out-of-bounds Read in nilfs_iget_test

Status: auto-obsoleted due to no activity on 2023/11/04 02:15
Reported-by: syzbot+577704f3de199b00265f@syzkaller.appspotmail.com
First crash: 974d, last: 974d
▶ ▼ 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 459d 548d 0/3 auto-obsoleted due to no activity on 2025/04/02 20:58
linux-5.15 KASAN: slab-out-of-bounds Read in nilfs_iget_test 17 2 902d 942d 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 2d15h 2d15h 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 481d 481d 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 1068d 1270d 0/29 auto-obsoleted due to no activity on 2023/08/22 15:25

Sample crash report:
loop5: detected capacity change from 0 to 4096
NILFS (loop5): invalid segment: Checksum error in segment payload
NILFS (loop5): 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 ffff88808947ac80 by task syz-executor.5/13298

CPU: 1 PID: 13298 Comm: syz-executor.5 Not tainted 6.1.41-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
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:915
 ilookup5_nowait fs/inode.c:1470 [inline]
 ilookup5+0x9d/0x200 fs/inode.c:1499
 iget5_locked+0x33/0x270 fs/inode.c:1280
 nilfs_iget_locked+0x127/0x180 fs/nilfs2/inode.c:605
 nilfs_dat_read+0xbb/0x300 fs/nilfs2/dat.c:490
 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:611
 vfs_get_tree+0x88/0x270 fs/super.c:1553
 do_new_mount+0x28b/0xae0 fs/namespace.c:3040
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x2d5/0x3c0 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
RIP: 0033:0x7f22bd87e22a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f22be668ee8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f22be668f80 RCX: 00007f22bd87e22a
RDX: 00000000200000c0 RSI: 0000000020000100 RDI: 00007f22be668f40
RBP: 00000000200000c0 R08: 00007f22be668f80 R09: 0000000000004800
R10: 0000000000004800 R11: 0000000000000202 R12: 0000000020000100
R13: 00007f22be668f40 R14: 0000000000000da6 R15: 0000000020000040
 </TASK>

Allocated by task 12699:
 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+0x50/0x370 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:3131 [inline]
 f2fs_alloc_inode+0x171/0x540 fs/f2fs/super.c:1366
 alloc_inode fs/inode.c:259 [inline]
 iget_locked+0x1c8/0x830 fs/inode.c:1328
 f2fs_iget+0x52/0x4ac0 fs/f2fs/inode.c:497
 f2fs_fill_super+0x6037/0x7cb0 fs/f2fs/super.c:4341
 mount_bdev+0x2c9/0x3f0 fs/super.c:1423
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1553
 do_new_mount+0x28b/0xae0 fs/namespace.c:3040
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x2d5/0x3c0 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

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:2799
 dispose_list fs/inode.c:697 [inline]
 evict_inodes+0x601/0x6a0 fs/inode.c:747
 generic_shutdown_super+0x94/0x340 fs/super.c:480
 kill_block_super+0x7a/0xe0 fs/super.c:1450
 kill_f2fs_super+0x2ff/0x3c0 fs/f2fs/super.c:4612
 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:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

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:2799
 f2fs_put_super+0x61c/0xc00 fs/f2fs/super.c:1594
 generic_shutdown_super+0x130/0x340 fs/super.c:501
 kill_block_super+0x7a/0xe0 fs/super.c:1450
 kill_f2fs_super+0x2ff/0x3c0 fs/f2fs/super.c:4612
 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:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88808947a3a0
 which belongs to the cache f2fs_inode_cache of size 2152
The buggy address is located 120 bytes to the right of
 2152-byte region [ffff88808947a3a0, ffff88808947ac08)

The buggy address belongs to the physical page:
page:ffffea0002251e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888089479ab8 pfn:0x89478
head:ffffea0002251e00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88807c969501
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea000228d808 ffff88801378c048 ffff888141b93280
raw: ffff888089479ab8 00000000000e0001 00000001ffffffff ffff88807c969501
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 11012, tgid 11011 (syz-executor.4), ts 627301080154, free_ts 626398548805
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2533
 prep_new_page mm/page_alloc.c:2540 [inline]
 get_page_from_freelist+0x32ed/0x3480 mm/page_alloc.c:4292
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5559
 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+0xa71/0x1080 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:3131 [inline]
 f2fs_alloc_inode+0x171/0x540 fs/f2fs/super.c:1366
 alloc_inode fs/inode.c:259 [inline]
 iget_locked+0x1c8/0x830 fs/inode.c:1328
 f2fs_iget+0x52/0x4ac0 fs/f2fs/inode.c:497
 f2fs_fill_super+0x4ab4/0x7cb0 fs/f2fs/super.c:4231
 mount_bdev+0x2c9/0x3f0 fs/super.c:1423
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1553
 do_new_mount+0x28b/0xae0 fs/namespace.c:3040
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3568
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1460 [inline]
 free_pcp_prepare mm/page_alloc.c:1510 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3388
 free_unref_page+0x98/0x570 mm/page_alloc.c:3484
 qlist_free_all+0x22/0x60 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x162/0x180 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+0x50/0x370 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
 getname_flags+0xb8/0x4e0 fs/namei.c:139
 vfs_fstatat fs/stat.c:266 [inline]
 __do_sys_newfstatat fs/stat.c:437 [inline]
 __se_sys_newfstatat fs/stat.c:431 [inline]
 __x64_sys_newfstatat+0x130/0x1e0 fs/stat.c:431
 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:
 ffff88808947ab80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808947ac00: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88808947ac80: fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff88808947ad00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88808947ad80: 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
2023/07/27 02:14 linux-6.1.y 5302e81aa209 41fe1bae .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.