[syzbot] [gfs2?] KASAN: stack-out-of-bounds Read in gfs2_dump_glock

From: syzbot
Date: Sat May 04 2024 - 18:05:51 EST


Hello,

syzbot found the following issue on:

HEAD commit: 98369dccd2f8 Merge tag 'wq-for-6.9-rc6-fixes' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1052837f180000
kernel config: https://syzkaller.appspot.com/x/.config?x=3310e643b6ef5d69
dashboard link: https://syzkaller.appspot.com/bug?extid=7efd59a5a532c57037e6
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=178d4f0f180000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-98369dcc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b0973ccd58a3/vmlinux-98369dcc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ce67494bf7bc/bzImage-98369dcc.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/5785eead10b2/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7efd59a5a532c57037e6@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: stack-out-of-bounds in gfs2_dump_glock+0x18b1/0x1c80 fs/gfs2/glock.c:2406
Read of size 8 at addr ffffc9000e97fd20 by task syz-executor.3/8992

CPU: 0 PID: 8992 Comm: syz-executor.3 Not tainted 6.9.0-rc6-syzkaller-00022-g98369dccd2f8 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:488
kasan_report+0xd9/0x110 mm/kasan/report.c:601
gfs2_dump_glock+0x18b1/0x1c80 fs/gfs2/glock.c:2406
gfs2_consist_inode_i+0x104/0x150 fs/gfs2/util.c:456
gfs2_dirent_scan+0x2fc/0x3c0 fs/gfs2/dir.c:602
gfs2_dirent_search+0x459/0x5c0 fs/gfs2/dir.c:850
gfs2_dir_search+0x98/0x2e0 fs/gfs2/dir.c:1650
gfs2_lookupi+0x4b9/0x6f0 fs/gfs2/inode.c:340
__gfs2_lookup+0xa1/0x290 fs/gfs2/inode.c:896
gfs2_atomic_open+0xdd/0x240 fs/gfs2/inode.c:1297
atomic_open fs/namei.c:3360 [inline]
lookup_open.isra.0+0xc98/0x13c0 fs/namei.c:3468
open_last_lookups fs/namei.c:3566 [inline]
path_openat+0x92f/0x2990 fs/namei.c:3796
do_filp_open+0x1dc/0x430 fs/namei.c:3826
do_sys_openat2+0x17a/0x1e0 fs/open.c:1406
do_sys_open fs/open.c:1421 [inline]
__do_sys_open fs/open.c:1429 [inline]
__se_sys_open fs/open.c:1425 [inline]
__x64_sys_open+0x154/0x1e0 fs/open.c:1425
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb72827dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb728fab0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fb7283ac050 RCX: 00007fb72827dea9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200025c0
RBP: 00007fb7282ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fb7283ac050 R15: 00007ffd1c875b78
</TASK>

The buggy address belongs to the virtual mapping at
[ffffc9000e978000, ffffc9000e981000) created by:
kernel_clone+0xfd/0x980 kernel/fork.c:2797

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x287e1
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 8982, tgid 1444384437 (syz-executor.3), ts 8982, free_ts 287764902699
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
prep_new_page mm/page_alloc.c:1541 [inline]
get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
__alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
alloc_pages_mpol+0x275/0x610 mm/mempolicy.c:2264
vm_area_alloc_pages mm/vmalloc.c:3561 [inline]
__vmalloc_area_node mm/vmalloc.c:3637 [inline]
__vmalloc_node_range+0xa26/0x14b0 mm/vmalloc.c:3818
alloc_thread_stack_node kernel/fork.c:309 [inline]
dup_task_struct kernel/fork.c:1115 [inline]
copy_process+0xe56/0x9090 kernel/fork.c:2220
kernel_clone+0xfd/0x980 kernel/fork.c:2797
__do_sys_clone3+0x1f5/0x270 kernel/fork.c:3098
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 8955 tgid 8954 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1141 [inline]
free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
free_unref_folios+0x256/0xad0 mm/page_alloc.c:2536
folios_put_refs+0x487/0x6d0 mm/swap.c:1034
folio_batch_release include/linux/pagevec.h:101 [inline]
truncate_inode_pages_range+0xd12/0xe90 mm/truncate.c:419
kill_bdev block/bdev.c:85 [inline]
set_blocksize+0x2a3/0x350 block/bdev.c:161
sb_set_blocksize+0x47/0x120 block/bdev.c:170
init_sb+0xaa9/0x10e0 fs/gfs2/ops_fstype.c:523
gfs2_fill_super+0x1826/0x2bf0 fs/gfs2/ops_fstype.c:1230
get_tree_bdev+0x36f/0x610 fs/super.c:1614
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1341
vfs_get_tree+0x8f/0x380 fs/super.c:1779
do_new_mount fs/namespace.c:3352 [inline]
path_mount+0x14e6/0x1f20 fs/namespace.c:3679
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount fs/namespace.c:3875 [inline]
__x64_sys_mount+0x297/0x320 fs/namespace.c:3875
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
ffffc9000e97fc00: 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 00
ffffc9000e97fc80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc9000e97fd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1
^
ffffc9000e97fd80: f1 f1 04 f3 f3 f3 00 00 00 00 00 00 00 00 00 00
ffffc9000e97fe00: 00 00 f1 f1 f1 f1 00 00 00 00 00 00 00 00 00 00
==================================================================


---
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