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KASAN: use-after-free Read in hfsplus_btree_open (3)

Status: auto-obsoleted due to no activity on 2024/11/30 09:06
Reported-by: syzbot+f10c636a2290506d3fd4@syzkaller.appspotmail.com
First crash: 548d, last: 548d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: use-after-free Read in hfsplus_btree_open 19 2 866d 938d 0/3 auto-obsoleted due to no activity on 2024/01/17 21:37
linux-5.15 KASAN: use-after-free Read in hfsplus_btree_open 19 5 819d 1061d 0/3 auto-obsoleted due to no activity on 2024/03/04 05:58
linux-6.1 KASAN: use-after-free Read in hfsplus_btree_open (4) 19 1 23d 23d 0/3 upstream: reported on 2026/01/29 12:26
linux-6.1 KASAN: use-after-free Read in hfsplus_btree_open (2) 19 2 750d 760d 0/3 auto-obsoleted due to no activity on 2024/05/12 07:07
upstream KASAN: use-after-free Read in hfsplus_btree_open hfs 19 8 1033d 1174d 0/29 auto-obsoleted due to no activity on 2023/08/23 09:08
linux-5.15 KASAN: use-after-free Read in hfsplus_btree_open (2) 19 2 281d 351d 0/3 auto-obsoleted due to no activity on 2025/08/24 11:57

Sample crash report:
loop4: detected capacity change from 0 to 1024
==================================================================
BUG: KASAN: use-after-free in hfsplus_btree_open+0x927/0xd10 fs/hfsplus/btree.c:155
Read of size 4 at addr ffff888058412ab4 by task syz.4.3117/18407

CPU: 1 PID: 18407 Comm: syz.4.3117 Not tainted 6.1.106-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
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
 hfsplus_btree_open+0x927/0xd10 fs/hfsplus/btree.c:155
 hfsplus_fill_super+0xaba/0x1c90 fs/hfsplus/super.c:473
 mount_bdev+0x2c9/0x3f0 fs/super.c:1443
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbc54b7b61a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbc559d5e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fbc559d5ef0 RCX: 00007fbc54b7b61a
RDX: 00000000200000c0 RSI: 0000000020000100 RDI: 00007fbc559d5eb0
RBP: 00000000200000c0 R08: 00007fbc559d5ef0 R09: 0000000000000004
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000020000100
R13: 00007fbc559d5eb0 R14: 00000000000006e0 R15: 00000000200022c0
 </TASK>

Allocated by task 18075:
 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+0x52/0x3a0 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:3193 [inline]
 f2fs_alloc_inode+0x171/0x540 fs/f2fs/super.c:1419
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x1c8/0x830 fs/inode.c:1330
 f2fs_iget+0x52/0x4bb0 fs/f2fs/inode.c:483
 f2fs_fill_super+0x5ecc/0x7c40 fs/f2fs/super.c:4395
 mount_bdev+0x2c9/0x3f0 fs/super.c:1443
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

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:2844
 f2fs_fill_super+0x62af/0x7c40 fs/f2fs/super.c:4578
 mount_bdev+0x2c9/0x3f0 fs/super.c:1443
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

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:2844
 dispose_list fs/inode.c:699 [inline]
 evict_inodes+0x601/0x6a0 fs/inode.c:749
 generic_shutdown_super+0x94/0x340 fs/super.c:480
 kill_block_super+0x7a/0xe0 fs/super.c:1470
 kill_f2fs_super+0x2ff/0x3c0 fs/f2fs/super.c:4674
 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:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff888058412380
 which belongs to the cache f2fs_inode_cache of size 2144
The buggy address is located 1844 bytes inside of
 2144-byte region [ffff888058412380, ffff888058412be0)

The buggy address belongs to the physical page:
page:ffffea0001610400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888058412380 pfn:0x58410
head:ffffea0001610400 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888022580501
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888140fd0c80
raw: ffff888058412380 00000000800e000a 00000001ffffffff ffff888022580501
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 4468, tgid 4466 (syz.3.144), ts 149062764696, free_ts 146542551402
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x322e/0x33b0 mm/page_alloc.c:4290
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5558
 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+0xc20/0x1270 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:3193 [inline]
 f2fs_alloc_inode+0x171/0x540 fs/f2fs/super.c:1419
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x1c8/0x830 fs/inode.c:1330
 f2fs_iget+0x52/0x4bb0 fs/f2fs/inode.c:483
 f2fs_fill_super+0x4a53/0x7c40 fs/f2fs/super.c:4293
 mount_bdev+0x2c9/0x3f0 fs/super.c:1443
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 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+0x52/0x3a0 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+0xb8/0x4f0 fs/namei.c:139
 user_path_at_empty+0x28/0x60 fs/namei.c:2906
 do_readlinkat+0x114/0x3a0 fs/stat.c:468
 __do_sys_readlink fs/stat.c:501 [inline]
 __se_sys_readlink fs/stat.c:498 [inline]
 __x64_sys_readlink+0x7b/0x90 fs/stat.c:498
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff888058412980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888058412a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888058412a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888058412b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888058412b80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/22 09:05 linux-6.1.y ee5e09825b81 ca02180f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hfsplus_btree_open
* Struck through repros no longer work on HEAD.