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KASAN: use-after-free Read in udf_add_fid_counter

Status: auto-obsoleted due to no activity on 2024/04/03 16:10
Subsystems: udf
[Documentation on labels]
Reported-by: syzbot+efc88f6fc380cc917d25@syzkaller.appspotmail.com
First crash: 107d, last: 107d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: unable to handle kernel paging request in udf_add_fid_counter udf 1 364d 363d 0/26 auto-obsoleted due to no activity on 2023/08/20 21:50

Sample crash report:
UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000)
==================================================================
BUG: KASAN: use-after-free in udf_add_fid_counter+0x1c8/0x240
Read of size 4 at addr ffff88808d2830c8 by task syz-executor.0/16381

CPU: 1 PID: 16381 Comm: syz-executor.0 Not tainted 6.7.0-rc8-syzkaller-00024-gac865f00af29 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:475
 kasan_report+0x142/0x170 mm/kasan/report.c:588
 udf_add_fid_counter+0x1c8/0x240
 udf_add_nondir+0x2d0/0x3b0 fs/udf/namei.c:371
 lookup_open fs/namei.c:3477 [inline]
 open_last_lookups fs/namei.c:3546 [inline]
 path_openat+0x13fa/0x3290 fs/namei.c:3776
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_open fs/open.c:1460 [inline]
 __se_sys_open fs/open.c:1456 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1456
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f30cc67cce9
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:00007f30cd4930c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f30cc79bf80 RCX: 00007f30cc67cce9
RDX: 0000000000000000 RSI: 0000000000060142 RDI: 0000000020000000
RBP: 00007f30cc6c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f30cc79bf80 R15: 00007ffef369bdc8
 </TASK>

The buggy address belongs to the physical page:
page:ffffea000234a0c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8d283
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 ffffea000234a0c8 ffffea000234a0c8 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:
 ffff88808d282f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88808d283000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88808d283080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff88808d283100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88808d283180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/04 16:09 upstream ac865f00af29 28c42cff .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in udf_add_fid_counter
* Struck through repros no longer work on HEAD.