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KASAN: use-after-free Read in __ext4_iget (2)

Status: auto-obsoleted due to no activity on 2024/09/17 10:19
First crash: 173d, last: 155d
▶ ▼ Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: use-after-free Read in __ext4_iget 2 70d 112d 0/3 upstream: reported on 2024/08/01 05:00
linux-5.15 KASAN: use-after-free Read in __ext4_iget 12 23d 295d 0/3 upstream: reported on 2024/01/31 03:06
upstream KASAN: slab-use-after-free Read in __ext4_iget fs reiserfs 278 296d 533d 0/28 auto-obsoleted due to no activity on 2024/04/09 13:42
android-5-15 KASAN: use-after-free Read in __ext4_iget origin:lts syz 98 21h38m 512d 0/2 premoderation: reported syz repro on 2023/06/28 10:27
linux-5.15 KASAN: slab-out-of-bounds Read in __ext4_iget 6 400d 444d 0/3 auto-obsoleted due to no activity on 2024/01/25 22:09
android-54 KASAN: use-after-free Read in __ext4_iget 13 272d 479d 0/2 auto-obsoleted due to no activity on 2024/05/22 19:07
android-5-10 KASAN: use-after-free Read in __ext4_iget syz 112 2d00h 512d 0/2 premoderation: reported syz repro on 2023/06/28 15:01
linux-6.1 KASAN: slab-out-of-bounds Read in __ext4_iget 14 234d 490d 0/3 auto-obsoleted due to no activity on 2024/07/09 19:10

Sample crash report:
EXT4-fs (loop3): Quota format mount options ignored when QUOTA feature is enabled
EXT4-fs (loop3): Test dummy encryption mode enabled
==================================================================
BUG: KASAN: use-after-free in check_igot_inode fs/ext4/inode.c:4953 [inline]
BUG: KASAN: use-after-free in __ext4_iget+0x384/0x4330 fs/ext4/inode.c:5001
Read of size 8 at addr ffff8881d0549510 by task syz-executor.3/2330

CPU: 1 PID: 2330 Comm: syz-executor.3 Tainted: G        W         5.4.274-syzkaller-00002-g6f97bd951d82 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x241 lib/dump_stack.c:118
 print_address_description+0x8c/0x600 mm/kasan/report.c:384
 __kasan_report+0xf3/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 check_igot_inode fs/ext4/inode.c:4953 [inline]
 __ext4_iget+0x384/0x4330 fs/ext4/inode.c:5001
 ext4_quota_enable fs/ext4/super.c:6056 [inline]
 ext4_enable_quotas+0x528/0x940 fs/ext4/super.c:6092
 ext4_fill_super+0x84f0/0x8d90 fs/ext4/super.c:4708
 mount_bdev+0x267/0x370 fs/super.c:1426
 legacy_get_tree+0xdf/0x170 fs/fs_context.c:648
 vfs_get_tree+0x85/0x260 fs/super.c:1556
 do_new_mount+0x292/0x570 fs/namespace.c:2843
 do_mount+0x688/0xe10 fs/namespace.c:3163
 ksys_mount+0xc2/0xf0 fs/namespace.c:3372
 __do_sys_mount fs/namespace.c:3386 [inline]
 __se_sys_mount fs/namespace.c:3383 [inline]
 __x64_sys_mount+0xb1/0xc0 fs/namespace.c:3383
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f59d253362a
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:00007f59d18abef8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f59d18abf80 RCX: 00007f59d253362a
RDX: 0000000020000080 RSI: 0000000020000140 RDI: 00007f59d18abf40
RBP: 0000000020000080 R08: 00007f59d18abf80 R09: 0000000000800000
R10: 0000000000800000 R11: 0000000000000202 R12: 0000000020000140
R13: 00007f59d18abf40 R14: 00000000000004f9 R15: 000000000000002c

Allocated by task 1698:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842
 f2fs_alloc_inode+0x22/0x3c0 fs/f2fs/super.c:1241
 alloc_inode fs/inode.c:231 [inline]
 iget_locked+0x143/0x790 fs/inode.c:1234
 f2fs_iget+0x52/0x4970 fs/f2fs/inode.c:490
 f2fs_fill_super+0x4ce5/0x8310 fs/f2fs/super.c:3963
 mount_bdev+0x267/0x370 fs/super.c:1426
 legacy_get_tree+0xdf/0x170 fs/fs_context.c:648
 vfs_get_tree+0x85/0x260 fs/super.c:1556
 do_new_mount+0x292/0x570 fs/namespace.c:2843
 do_mount+0x688/0xe10 fs/namespace.c:3163
 ksys_mount+0xc2/0xf0 fs/namespace.c:3372
 __do_sys_mount fs/namespace.c:3386 [inline]
 __se_sys_mount fs/namespace.c:3383 [inline]
 __x64_sys_mount+0xb1/0xc0 fs/namespace.c:3383
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Freed by task 10:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook mm/slub.c:1494 [inline]
 slab_free mm/slub.c:3080 [inline]
 kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096
 __rcu_reclaim kernel/rcu/rcu.h:222 [inline]
 rcu_do_batch+0x492/0xa00 kernel/rcu/tree.c:2167
 rcu_core+0x4c8/0xcb0 kernel/rcu/tree.c:2387
 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292

The buggy address belongs to the object at ffff8881d0549050
 which belongs to the cache f2fs_inode_cache of size 1264
The buggy address is located 1216 bytes inside of
 1264-byte region [ffff8881d0549050, ffff8881d0549540)
The buggy address belongs to the page:
page:ffffea0007415200 refcount:1 mapcount:0 mapping:ffff8881f0f6f900 index:0xffff8881d054ab80 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 0000000000000000 0000000100000001 ffff8881f0f6f900
raw: ffff8881d054ab80 0000000080170011 00000001ffffffff 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 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893
 alloc_slab_page+0x39/0x3c0 mm/slub.c:343
 allocate_slab mm/slub.c:1683 [inline]
 new_slab+0x97/0x440 mm/slub.c:1749
 new_slab_objects mm/slub.c:2505 [inline]
 ___slab_alloc+0x2fe/0x490 mm/slub.c:2667
 __slab_alloc+0x62/0xa0 mm/slub.c:2707
 slab_alloc_node mm/slub.c:2792 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0x109/0x250 mm/slub.c:2842
 f2fs_alloc_inode+0x22/0x3c0 fs/f2fs/super.c:1241
 alloc_inode fs/inode.c:231 [inline]
 iget_locked+0x143/0x790 fs/inode.c:1234
 f2fs_iget+0x52/0x4970 fs/f2fs/inode.c:490
 f2fs_fill_super+0x68e2/0x8310 fs/f2fs/super.c:4071
 mount_bdev+0x267/0x370 fs/super.c:1426
 legacy_get_tree+0xdf/0x170 fs/fs_context.c:648
 vfs_get_tree+0x85/0x260 fs/super.c:1556
 do_new_mount+0x292/0x570 fs/namespace.c:2843
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 free_pcp_prepare mm/page_alloc.c:1233 [inline]
 free_unref_page_prepare+0x297/0x380 mm/page_alloc.c:3085
 free_unref_page_list+0x10a/0x590 mm/page_alloc.c:3154
 release_pages+0xad8/0xb20 mm/swap.c:842
 __pagevec_release+0xc3/0x150 mm/swap.c:862
 pagevec_release include/linux/pagevec.h:88 [inline]
 shmem_undo_range+0x8a5/0x1ad0 mm/shmem.c:875
 shmem_truncate_range mm/shmem.c:997 [inline]
 shmem_evict_inode+0x218/0x9a0 mm/shmem.c:1097
 evict+0x29b/0x6a0 fs/inode.c:575
 __dentry_kill+0x429/0x630 fs/dcache.c:579
 dentry_kill+0xb8/0x280 fs/dcache.c:673
 dput+0x3c/0x80 fs/dcache.c:860
 __fput+0x443/0x680 fs/file_table.c:294
 task_work_run+0x140/0x170 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xcaf/0x2bc0 kernel/exit.c:859
 do_group_exit+0x138/0x300 kernel/exit.c:982
 get_signal+0xdb1/0x1440 kernel/signal.c:2735
 do_signal+0xb0/0x11f0 arch/x86/kernel/signal.c:809

Memory state around the buggy address:
 ffff8881d0549400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881d0549480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881d0549500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                         ^
 ffff8881d0549580: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
 ffff8881d0549600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
EXT4-fs warning (device loop3): ext4_enable_quotas:6100: Failed to enable quota tracking (type=0, err=-13, ino=3). Please run e2fsck to fix.
EXT4-fs (loop3): mount failed

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/19 10:15 android12-5.4 6f97bd951d82 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-4-kasan KASAN: use-after-free Read in __ext4_iget
2024/06/18 07:26 android12-5.4 6f97bd951d82 ce6011bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-4-kasan KASAN: use-after-free Read in __ext4_iget
2024/06/17 23:27 android12-5.4 6f97bd951d82 1f11cfd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-4-kasan KASAN: use-after-free Read in __ext4_iget
2024/06/01 04:12 android12-5.4 8322246edffa 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-4-kasan KASAN: use-after-free Read in __ext4_iget
* Struck through repros no longer work on HEAD.