KASAN: slab-out-of-bounds Read in ext4_enable_quotas

Status: auto-obsoleted due to no activity on 2023/08/09 14:45
Reported-by: syzbot+0adb6d6ed07c48d429ed@syzkaller.appspotmail.com
First crash: 1264d, last: 1257d
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in ext4_enable_quotas f2fs 17 syz, C error error 29 1241d 1454d 0/29 auto-obsoleted due to no activity on 2023/08/22 15:17
linux-6.1 KASAN: slab-out-of-bounds Read in ext4_enable_quotas (2) 17 1 1115d 1115d 0/3 auto-obsoleted due to no activity on 2023/12/09 07:13
linux-5.15 KASAN: slab-out-of-bounds Read in ext4_enable_quotas 17 1 1253d 1253d 0/3 auto-obsoleted due to no activity on 2023/08/13 11:53

Sample crash report:
loop3: detected capacity change from 0 to 512
==================================================================
BUG: KASAN: slab-out-of-bounds in lockdep_set_quota_inode fs/ext4/super.c:6822 [inline]
BUG: KASAN: slab-out-of-bounds in ext4_quota_enable fs/ext4/super.c:6953 [inline]
BUG: KASAN: slab-out-of-bounds in ext4_enable_quotas+0x5d3/0xd40 fs/ext4/super.c:6980
Read of size 8 at addr ffff8880a1dde1d0 by task syz-executor.3/19707

CPU: 1 PID: 19707 Comm: syz-executor.3 Not tainted 6.1.22-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
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
 lockdep_set_quota_inode fs/ext4/super.c:6822 [inline]
 ext4_quota_enable fs/ext4/super.c:6953 [inline]
 ext4_enable_quotas+0x5d3/0xd40 fs/ext4/super.c:6980
 __ext4_fill_super fs/ext4/super.c:5516 [inline]
 ext4_fill_super+0x81c4/0x8b20 fs/ext4/super.c:5659
 get_tree_bdev+0x3fe/0x620 fs/super.c:1346
 vfs_get_tree+0x88/0x270 fs/super.c:1553
 do_new_mount+0x28b/0xad0 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: 0033:0x7f13ac68d69a
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:00007f13ad446f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000000004a6 RCX: 00007f13ac68d69a
RDX: 00000000200004c0 RSI: 0000000020000500 RDI: 00007f13ad446fe0
RBP: 00007f13ad447020 R08: 00007f13ad447020 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000200004c0
R13: 0000000020000500 R14: 00007f13ad446fe0 R15: 0000000020000240
 </TASK>

Allocated by task 19040:
 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:1286
 f2fs_iget+0x51/0x4de0 fs/f2fs/inode.c:505
 f2fs_fill_super+0x4ab4/0x7cb0 fs/f2fs/super.c:4231
 mount_bdev+0x26d/0x3a0 fs/super.c:1423
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1553
 do_new_mount+0x28b/0xad0 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:2798
 f2fs_put_super+0x65d/0xc00 fs/f2fs/super.c:1597
 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

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:2798
 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 ffff8880a1ddd910
 which belongs to the cache f2fs_inode_cache of size 2152
The buggy address is located 88 bytes to the right of
 2152-byte region [ffff8880a1ddd910, ffff8880a1dde178)

The buggy address belongs to the physical page:
page:ffffea0002877600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880a1ddc740 pfn:0xa1dd8
head:ffffea0002877600 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888098e8c301
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff8881469ebdc0
raw: ffff8880a1ddc740 00000000800e0006 00000001ffffffff ffff888098e8c301
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 13925, tgid 13924 (syz-executor.1), ts 1046319353475, free_ts 1045955026690
 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:1286
 f2fs_iget+0x51/0x4de0 fs/f2fs/inode.c:505
 f2fs_fill_super+0x5f74/0x7cb0 fs/f2fs/super.c:4333
 mount_bdev+0x26d/0x3a0 fs/super.c:1423
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1553
 do_new_mount+0x28b/0xad0 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
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+0xf5e/0x1110 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
 user_path_at_empty+0x2a/0x180 fs/namei.c:2875
 user_path_at include/linux/namei.h:57 [inline]
 ksys_umount fs/namespace.c:1822 [inline]
 __do_sys_umount fs/namespace.c:1830 [inline]
 __se_sys_umount fs/namespace.c:1828 [inline]
 __x64_sys_umount+0xf0/0x170 fs/namespace.c:1828
 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:
 ffff8880a1dde080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a1dde100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc
>ffff8880a1dde180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc 00
                                                 ^
 ffff8880a1dde200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880a1dde280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/04 20:31 linux-6.1.y 3b29299e5f60 928dd177 .config console log report info ci2-linux-6-1-kasan KASAN: slab-out-of-bounds Read in ext4_enable_quotas
2023/04/11 14:43 linux-6.1.y 543aff194ab6 71147e29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: slab-out-of-bounds Read in ext4_enable_quotas
* Struck through repros no longer work on HEAD.