loop0: detected capacity change from 0 to 2048
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
loop0: detected capacity change from 2048 to 64
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BUG: KASAN: use-after-free in ext4_xattr_list_entries+0x302/0x3d0 fs/ext4/xattr.c:724
Read of size 4 at addr ffff8880539bc014 by task syz.0.0/5329
CPU: 0 UID: 0 PID: 5329 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
ext4_xattr_list_entries+0x302/0x3d0 fs/ext4/xattr.c:724
ext4_xattr_ibody_list fs/ext4/xattr.c:793 [inline]
ext4_listxattr+0x229/0x680 fs/ext4/xattr.c:818
vfs_listxattr fs/xattr.c:516 [inline]
listxattr+0x19d/0x380 fs/xattr.c:941
filename_listxattr fs/xattr.c:974 [inline]
path_listxattrat+0x1a3/0x3f0 fs/xattr.c:1001
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2f07b9de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2f08a08fe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000c2
RAX: ffffffffffffffda RBX: 00007f2f07e25fa0 RCX: 00007f2f07b9de59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000000c0
RBP: 00007f2f07c33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2f07e26038 R14: 00007f2f07e25fa0 R15: 00007ffe2f81fd08
</TASK>
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x539bc
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff00000000000 ffffea00014e6f48 ffffea00014a6688 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)
Memory state around the buggy address:
ffff8880539bbf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8880539bbf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880539bc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8880539bc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8880539bc100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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