syzbot


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

Status: upstream: reported on 2022/10/04 08:55
Reported-by: syzbot+cac676135771fc8f1eb2@syzkaller.appspotmail.com
First crash: 57d, last: 13d

Sample crash report:
loop1: detected capacity change from 0 to 2048
==================================================================
BUG: KASAN: slab-out-of-bounds in nilfs_iget_test+0xa1/0x330 fs/nilfs2/inode.c:544
Read of size 8 at addr ffff88808ccba378 by task syz-executor.1/13707

CPU: 1 PID: 13707 Comm: syz-executor.1 Not tainted 6.1.0-rc5-syzkaller-00008-ge01d50cbd6ee #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:284
 print_report+0x107/0x1f0 mm/kasan/report.c:395
 kasan_report+0xcd/0x100 mm/kasan/report.c:495
 nilfs_iget_test+0xa1/0x330 fs/nilfs2/inode.c:544
 find_inode+0x1ac/0x4c0 fs/inode.c:915
 ilookup5_nowait fs/inode.c:1428 [inline]
 ilookup5+0x9d/0x1d0 fs/inode.c:1457
 iget5_locked+0x33/0x270 fs/inode.c:1238
 nilfs_iget_locked+0x140/0x1d0 fs/nilfs2/inode.c:605
 nilfs_dat_read+0xbd/0x300 fs/nilfs2/dat.c:483
 nilfs_load_super_root fs/nilfs2/the_nilfs.c:120 [inline]
 load_nilfs+0x4c8/0xfc0 fs/nilfs2/the_nilfs.c:269
 nilfs_fill_super+0x27e/0x5d0 fs/nilfs2/super.c:1059
 nilfs_mount+0x613/0x9b0 fs/nilfs2/super.c:1315
 legacy_get_tree+0xea/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1531
 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
RIP: 0033:0x7f805168cb6a
Code: 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 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:00007f8052421f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f805168cb6a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f8052421fe0
RBP: 00007f8052422020 R08: 00007f8052422020 R09: 0000000020000000
R10: 0000000000004000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000100 R14: 00007f8052421fe0 R15: 0000000020000fc0
 </TASK>

Allocated by task 12786:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x3d/0x60 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:325
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slab.h:737 [inline]
 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+0x180/0x2e0 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3117 [inline]
 f2fs_alloc_inode+0x14d/0x520 fs/f2fs/super.c:1366
 alloc_inode fs/inode.c:259 [inline]
 iget_locked+0x191/0x830 fs/inode.c:1286
 f2fs_iget+0x51/0x4bb0 fs/f2fs/inode.c:505
 f2fs_fill_super+0x38b1/0x6c40 fs/f2fs/super.c:4222
 mount_bdev+0x26c/0x3a0 fs/super.c:1401
 legacy_get_tree+0xea/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1531
 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

Last potentially related work creation:
 kasan_save_stack+0x2b/0x50 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:481
 call_rcu+0x163/0x9c0 kernel/rcu/tree.c:2798
 f2fs_fill_super+0x3c5e/0x6c40 fs/f2fs/super.c:4534
 mount_bdev+0x26c/0x3a0 fs/super.c:1401
 legacy_get_tree+0xea/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1531
 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

Second to last potentially related work creation:
 kasan_save_stack+0x2b/0x50 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:481
 call_rcu+0x163/0x9c0 kernel/rcu/tree.c:2798
 f2fs_fill_super+0x5669/0x6c40 fs/f2fs/super.c:4516
 mount_bdev+0x26c/0x3a0 fs/super.c:1401
 legacy_get_tree+0xea/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1531
 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

The buggy address belongs to the object at ffff88808ccb9aa0
 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 [ffff88808ccb9aa0, ffff88808ccba300)

The buggy address belongs to the physical page:
page:ffffea0002332e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88808ccb9aa0 pfn:0x8ccb8
head:ffffea0002332e00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888077965a01
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88801ca82a00
raw: ffff88808ccb9aa0 00000000800e000c 00000001ffffffff ffff888077965a01
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 11233, tgid 11231 (syz-executor.2), ts 281566872083, free_ts 242828325982
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x742/0x7c0 mm/page_alloc.c:4288
 __alloc_pages+0x259/0x560 mm/page_alloc.c:5555
 alloc_slab_page+0x70/0xf0 mm/slub.c:1794
 allocate_slab+0x5e/0x4b0 mm/slub.c:1939
 new_slab mm/slub.c:1992 [inline]
 ___slab_alloc+0x782/0xe20 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+0x233/0x2e0 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3117 [inline]
 f2fs_alloc_inode+0x14d/0x520 fs/f2fs/super.c:1366
 alloc_inode fs/inode.c:259 [inline]
 iget_locked+0x191/0x830 fs/inode.c:1286
 f2fs_iget+0x51/0x4bb0 fs/f2fs/inode.c:505
 f2fs_fill_super+0x38b1/0x6c40 fs/f2fs/super.c:4222
 mount_bdev+0x26c/0x3a0 fs/super.c:1401
 legacy_get_tree+0xea/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1531
 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
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare+0x80c/0x8f0 mm/page_alloc.c:1509
 free_unref_page_prepare mm/page_alloc.c:3387 [inline]
 free_unref_page+0x7d/0x5f0 mm/page_alloc.c:3483
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1ab/0x200 mm/slub.c:2586
 put_cpu_partial+0x106/0x170 mm/slub.c:2662
 qlist_free_all+0x2b/0x70 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x169/0x180 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:302
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slab.h:737 [inline]
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x1d7/0x310 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc+0x9e/0x1a0 mm/slab_common.c:968
 kmalloc_array include/linux/slab.h:605 [inline]
 kcalloc include/linux/slab.h:636 [inline]
 ext4_find_extent+0x342/0xd90 fs/ext4/extents.c:914
 ext4_ext_map_blocks+0x1d9/0x6880 fs/ext4/extents.c:4103
 ext4_map_blocks+0xa49/0x1cc0 fs/ext4/inode.c:645
 ext4_convert_unwritten_extents+0x2ed/0x700 fs/ext4/extents.c:4812
 ext4_convert_unwritten_io_end_vec+0x11c/0x1d0 fs/ext4/extents.c:4851
 ext4_end_io_end fs/ext4/page-io.c:186 [inline]
 ext4_do_flush_completed_IO fs/ext4/page-io.c:259 [inline]
 ext4_end_io_rsv_work+0x380/0x6f0 fs/ext4/page-io.c:273
 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289

Memory state around the buggy address:
 ffff88808ccba200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808ccba280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88808ccba300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                                ^
 ffff88808ccba380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88808ccba400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (4):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-fs 2022/11/15 11:28 upstream e01d50cbd6ee 97de9cfc .config log report info KASAN: slab-out-of-bounds Read in nilfs_iget_test
ci2-upstream-fs 2022/11/13 11:44 upstream fef7fd48922d f42ee5d8 .config log report info KASAN: slab-out-of-bounds Read in nilfs_iget_test
ci2-upstream-fs 2022/11/12 09:40 upstream 8f2975c2bb4c f42ee5d8 .config log report info KASAN: slab-out-of-bounds Read in nilfs_iget_test
ci2-upstream-fs 2022/10/03 00:43 upstream a962b54e162c feb56351 .config log report info KASAN: slab-out-of-bounds Read in nilfs_iget_test
* Struck through repros no longer work on HEAD.