[syzbot] [ocfs2?] KASAN: use-after-free Read in ocfs2_search_dirblock

[syzbot <syzbot+b9704899e166798d57c9@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    d7a5aa4b3c00 Merge tag 'perf-tools-fixes-for-v6.11-2024-08..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1049fbc5980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7229118d88b4a71b
dashboard link: https://syzkaller.appspot.com/bug?extid=b9704899e166798d57c9
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14c4ba05980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12902209980000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-d7a5aa4b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/af15738cca6c/vmlinux-d7a5aa4b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/62dacb1384ee/bzImage-d7a5aa4b.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/f26a3130fa6e/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b9704899e166798d57c9@syzkaller.appspotmail.com

JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
==================================================================
BUG: KASAN: use-after-free in ocfs2_match fs/ocfs2/dir.c:334 [inline]
BUG: KASAN: use-after-free in ocfs2_search_dirblock+0x26b/0x830 fs/ocfs2/dir.c:367
Read of size 1 at addr ffff888012e06982 by task syz-executor341/5089

CPU: 0 UID: 0 PID: 5089 Comm: syz-executor341 Not tainted 6.11.0-rc3-syzkaller-00156-gd7a5aa4b3c00 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 ocfs2_match fs/ocfs2/dir.c:334 [inline]
 ocfs2_search_dirblock+0x26b/0x830 fs/ocfs2/dir.c:367
 ocfs2_find_entry_id fs/ocfs2/dir.c:414 [inline]
 ocfs2_find_entry+0x1169/0x2780 fs/ocfs2/dir.c:1078
 ocfs2_find_files_on_disk+0xff/0x360 fs/ocfs2/dir.c:1980
 ocfs2_lookup_ino_from_name+0xb1/0x1e0 fs/ocfs2/dir.c:2002
 ocfs2_lookup+0x292/0xa60 fs/ocfs2/namei.c:122
 lookup_open fs/namei.c:3556 [inline]
 open_last_lookups fs/namei.c:3647 [inline]
 path_openat+0x11cc/0x3470 fs/namei.c:3883
 do_filp_open+0x235/0x490 fs/namei.c:3913
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_openat fs/open.c:1447 [inline]
 __se_sys_openat fs/open.c:1442 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1442
 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: 0033:0x7f2501523169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd9f886d28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2501523169
RDX: 0000000000105042 RSI: 0000000020000080 RDI: 00000000ffffff9c
RBP: 00000000ffffffff R08: 000000000000447f R09: 0000000002800400
R10: 00000000000001ff R11: 0000000000000246 R12: 00007ffd9f886d70
R13: 00007ffd9f886db0 R14: 0000000001000000 R15: 0000000000000003
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x161 pfn:0x12e06
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000161 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4955, tgid 4955 (dhcpcd-run-hook), ts 57137576415, free_ts 66887393625
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493
 prep_new_page mm/page_alloc.c:1501 [inline]
 get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3442
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4700
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2321
 allocate_slab+0x5a/0x2f0 mm/slub.c:2484
 new_slab mm/slub.c:2537 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3723
 __slab_alloc+0x58/0xa0 mm/slub.c:3813
 __slab_alloc_node mm/slub.c:3866 [inline]
 slab_alloc_node mm/slub.c:4025 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x2a0 mm/slub.c:4044
 getname_flags+0xb7/0x540 fs/namei.c:139
 vfs_fstatat+0x12c/0x190 fs/stat.c:340
 __do_sys_newfstatat fs/stat.c:505 [inline]
 __se_sys_newfstatat fs/stat.c:499 [inline]
 __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:499
 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
page last free pid 5005 tgid 5005 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1094 [inline]
 free_unref_page+0xd22/0xea0 mm/page_alloc.c:2612
 discard_slab mm/slub.c:2583 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3051
 put_cpu_partial+0x17c/0x250 mm/slub.c:3126
 __slab_free+0x2ea/0x3d0 mm/slub.c:4343
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3988 [inline]
 slab_alloc_node mm/slub.c:4037 [inline]
 kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044
 getname_flags+0xb7/0x540 fs/namei.c:139
 vfs_fstatat+0x12c/0x190 fs/stat.c:340
 __do_sys_newfstatat fs/stat.c:505 [inline]
 __se_sys_newfstatat fs/stat.c:499 [inline]
 __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:499
 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:
 ffff888012e06880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888012e06900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888012e06980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888012e06a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888012e06a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================


---
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