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

Status: auto-obsoleted due to no activity on 2024/05/12 07:07
Reported-by: syzbot+f7a1dc366d96d138ba2c@syzkaller.appspotmail.com
First crash: 748d, last: 738d
▶ ▼ 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 854d 926d 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 807d 1049d 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 11d 11d 0/3 upstream: reported on 2026/01/29 12:26
linux-6.1 KASAN: use-after-free Read in hfsplus_btree_open (3) 19 1 536d 536d 0/3 auto-obsoleted due to no activity on 2024/11/30 09:06
upstream KASAN: use-after-free Read in hfsplus_btree_open hfs 19 8 1021d 1162d 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 269d 339d 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 ffff88803f12b394 by task syz-executor.4/13635

CPU: 1 PID: 13635 Comm: syz-executor.4 Not tainted 6.1.76-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
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:1432
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1562
 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+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f940347f4aa
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:00007f9404126ef8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f9404126f80 RCX: 00007f940347f4aa
RDX: 0000000020000140 RSI: 0000000020000180 RDI: 00007f9404126f40
RBP: 0000000020000140 R08: 00007f9404126f80 R09: 0000000000004008
R10: 0000000000004008 R11: 0000000000000202 R12: 0000000020000180
R13: 00007f9404126f40 R14: 0000000000000696 R15: 00000000200001c0
 </TASK>

Allocated by task 7389:
 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:3177 [inline]
 f2fs_alloc_inode+0x171/0x540 fs/f2fs/super.c:1400
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x1c8/0x830 fs/inode.c:1330
 f2fs_iget+0x52/0x4a30 fs/f2fs/inode.c:503
 f2fs_fill_super+0x5ecc/0x7c40 fs/f2fs/super.c:4367
 mount_bdev+0x2c9/0x3f0 fs/super.c:1432
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1562
 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+0x3d/0xb0 arch/x86/entry/common.c:81
 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:2844
 f2fs_fill_super+0x62af/0x7c40 fs/f2fs/super.c:4550
 mount_bdev+0x2c9/0x3f0 fs/super.c:1432
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1562
 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+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88803f12ac60
 which belongs to the cache f2fs_inode_cache of size 2144
The buggy address is located 1844 bytes inside of
 2144-byte region [ffff88803f12ac60, ffff88803f12b4c0)

The buggy address belongs to the physical page:
page:ffffea0000fc4a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88803f128000 pfn:0x3f128
head:ffffea0000fc4a00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888028102001
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000001 ffff8880173f3000
raw: ffff88803f128000 00000000800e0001 00000001ffffffff ffff888028102001
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 7346, tgid 7345 (syz-executor.4), ts 458891480784, free_ts 0
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513
 prep_new_page mm/page_alloc.c:2520 [inline]
 get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5545
 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:3177 [inline]
 f2fs_alloc_inode+0x171/0x540 fs/f2fs/super.c:1400
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x61/0x1d0 fs/inode.c:1020
 new_inode+0x25/0x1d0 fs/inode.c:1048
 f2fs_new_inode+0x11d/0x1020 fs/f2fs/namei.c:191
 f2fs_mkdir+0x123/0x520 fs/f2fs/namei.c:760
 vfs_mkdir+0x3b6/0x590 fs/namei.c:4108
 do_mkdirat+0x225/0x360 fs/namei.c:4133
 __do_sys_mkdirat fs/namei.c:4148 [inline]
 __se_sys_mkdirat fs/namei.c:4146 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4146
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88803f12b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803f12b300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88803f12b380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88803f12b400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803f12b480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/02/02 07:06 linux-6.1.y e5c3b988b827 d61103fc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hfsplus_btree_open
2024/01/23 09:40 linux-6.1.y 8fd7f4462453 1c0ecc51 .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.