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KASAN: slab-use-after-free Read in jfs_readdir

Status: moderation: reported on 2024/12/25 09:50
Subsystems: jfs
[Documentation on labels]
Reported-by: syzbot+dc49f751ffdd2534c7aa@syzkaller.appspotmail.com
First crash: 5d13h, last: 2d09h
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in jfs_readdir jfs C error done 17 353d 714d 25/28 fixed on 2024/03/20 11:33
upstream UBSAN: array-index-out-of-bounds in jfs_readdir jfs C inconclusive 89 17d 269d 28/28 fixed on 2024/12/16 09:50
linux-5.15 UBSAN: array-index-out-of-bounds in jfs_readdir origin:upstream C error 29 14d 269d 0/3 upstream: reported C repro on 2024/04/01 00:20
linux-6.1 UBSAN: array-index-out-of-bounds in jfs_readdir origin:upstream missing-backport C error 46 5d21h 269d 0/3 upstream: reported C repro on 2024/04/01 00:16
linux-4.14 KASAN: slab-out-of-bounds Read in jfs_readdir jfs 1 714d 714d 0/1 upstream: reported on 2023/01/12 07:34
linux-4.19 KASAN: slab-out-of-bounds Read in jfs_readdir jfs 2 714d 714d 0/1 upstream: reported on 2023/01/12 07:27

Sample crash report:
loop1: detected capacity change from 0 to 32768
==================================================================
BUG: KASAN: slab-use-after-free in jfs_readdir+0x1b6e/0x3c50 fs/jfs/jfs_dtree.c:2904
Read of size 1 at addr ffff888053b4180d by task syz.1.165/7511

CPU: 1 UID: 0 PID: 7511 Comm: syz.1.165 Not tainted 6.13.0-rc4-syzkaller-00004-gf07044dd0df0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 jfs_readdir+0x1b6e/0x3c50 fs/jfs/jfs_dtree.c:2904
 wrap_directory_iterator+0x91/0xd0 fs/readdir.c:65
 iterate_dir+0x571/0x800 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:403 [inline]
 __se_sys_getdents64+0x1e2/0x4b0 fs/readdir.c:389
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc264385d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fc2651e5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fc264575fa0 RCX: 00007fc264385d29
RDX: 000000000000009e RSI: 0000000020000280 RDI: 0000000000000006
RBP: 00007fc264401aa8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc264575fa0 R15: 00007ffd6896e468
 </TASK>

Allocated by task 6457:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4119 [inline]
 slab_alloc_node mm/slub.c:4168 [inline]
 kmem_cache_alloc_lru_noprof+0x1dd/0x390 mm/slub.c:4187
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x65/0x1a0 fs/inode.c:336
 new_inode_pseudo fs/inode.c:1174 [inline]
 new_inode+0x22/0x1d0 fs/inode.c:1193
 diReadSpecial+0x52/0x680 fs/jfs/jfs_imap.c:426
 jfs_mount+0x3af/0x830 fs/jfs/jfs_mount.c:166
 jfs_fill_super+0x6b9/0xd90 fs/jfs/super.c:523
 get_tree_bdev_flags+0x48c/0x5c0 fs/super.c:1636
 vfs_get_tree+0x90/0x2b0 fs/super.c:1814
 do_new_mount+0x2be/0xb40 fs/namespace.c:3507
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 16:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4613 [inline]
 kmem_cache_free+0x195/0x410 mm/slub.c:4715
 rcu_do_batch kernel/rcu/tree.c:2567 [inline]
 rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950
 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:544
 __call_rcu_common kernel/rcu/tree.c:3086 [inline]
 call_rcu+0x167/0xa70 kernel/rcu/tree.c:3190
 destroy_inode fs/inode.c:391 [inline]
 evict+0x836/0x9a0 fs/inode.c:827
 jfs_umount+0x18e/0x3a0 fs/jfs/jfs_umount.c:65
 jfs_put_super+0x8a/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x139/0x2d0 fs/super.c:642
 kill_block_super+0x44/0x90 fs/super.c:1710
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888053b41270
 which belongs to the cache jfs_ip of size 2232
The buggy address is located 1437 bytes inside of
 freed 2232-byte region [ffff888053b41270, ffff888053b41b28)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888053b46568 pfn:0x53b40
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888027b51b01
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888146a803c0 dead000000000122 0000000000000000
raw: ffff888053b46568 00000000800d000a 00000001f5000000 ffff888027b51b01
head: 00fff00000000040 ffff888146a803c0 dead000000000122 0000000000000000
head: ffff888053b46568 00000000800d000a 00000001f5000000 ffff888027b51b01
head: 00fff00000000003 ffffea00014ed001 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_RECLAIMABLE), pid 6457, tgid 6456 (syz.3.64), ts 100548556215, free_ts 68853506971
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1558
 prep_new_page mm/page_alloc.c:1566 [inline]
 get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3476
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4753
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269
 alloc_slab_page+0x6a/0x110 mm/slub.c:2423
 allocate_slab+0x5a/0x2b0 mm/slub.c:2589
 new_slab mm/slub.c:2642 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830
 __slab_alloc+0x58/0xa0 mm/slub.c:3920
 __slab_alloc_node mm/slub.c:3995 [inline]
 slab_alloc_node mm/slub.c:4156 [inline]
 kmem_cache_alloc_lru_noprof+0x26c/0x390 mm/slub.c:4187
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x65/0x1a0 fs/inode.c:336
 new_inode_pseudo fs/inode.c:1174 [inline]
 new_inode+0x22/0x1d0 fs/inode.c:1193
 diReadSpecial+0x52/0x680 fs/jfs/jfs_imap.c:426
 jfs_mount+0x75/0x830 fs/jfs/jfs_mount.c:87
 jfs_fill_super+0x6b9/0xd90 fs/jfs/super.c:523
 get_tree_bdev_flags+0x48c/0x5c0 fs/super.c:1636
page last free pid 5945 tgid 5942 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 __free_pages_ok+0xbcf/0xe50 mm/page_alloc.c:1271
 __folio_put+0x2b3/0x360 mm/swap.c:112
 folio_put include/linux/mm.h:1489 [inline]
 free_large_kmalloc+0xfe/0x180 mm/slub.c:4732
 kfree+0x212/0x430 mm/slub.c:4755
 __btree_node_data_free+0x30e/0x550 fs/bcachefs/btree_cache.c:110
 btree_node_data_free fs/bcachefs/btree_cache.c:127 [inline]
 bch2_fs_btree_cache_exit+0xb1b/0x1530 fs/bcachefs/btree_cache.c:610
 __bch2_fs_free fs/bcachefs/super.c:557 [inline]
 bch2_fs_release+0x20e/0x7d0 fs/bcachefs/super.c:611
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22f/0x480 lib/kobject.c:737
 bch2_fs_alloc fs/bcachefs/super.c:960 [inline]
 bch2_fs_open+0x1ebe/0x2f80 fs/bcachefs/super.c:2065
 bch2_fs_get_tree+0x738/0x1710 fs/bcachefs/fs.c:2157
 vfs_get_tree+0x90/0x2b0 fs/super.c:1814
 do_new_mount+0x2be/0xb40 fs/namespace.c:3507
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888053b41700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888053b41780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888053b41800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888053b41880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888053b41900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/24 13:56 upstream f07044dd0df0 444551c4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in jfs_readdir
2024/12/21 09:45 upstream 499551201b5f d7f584ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root KASAN: slab-use-after-free Read in jfs_readdir
* Struck through repros no longer work on HEAD.