KASAN: use-after-free Read in reiserfs_fill_super

Status: upstream: reported C repro on 2024/10/20 14:12
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+1f000adf424897844a29@syzkaller.appspotmail.com
First crash: 644d, last: 14d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (3)
Date Name Commit Repro Result
2024/12/08 linux-6.1.y (ToT) e4d90d63d385 C [report] KASAN: use-after-free Read in reiserfs_fill_super
2024/10/23 upstream (ToT) c2ee9f594da8 C [report] KASAN: use-after-free Read in reiserfs_fill_super
2024/12/08 upstream (ToT) 7503345ac5f5 C Didn't crash
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in reiserfs_fill_super (3) fs 19 C error done 47 615d 660d 28/29 fixed on 2025/01/13 19:22
linux-5.15 KASAN: use-after-free Read in reiserfs_fill_super missing-backport origin:upstream 19 C error 8 4d13h 659d 0/3 upstream: reported C repro on 2024/10/04 20:48
upstream KASAN: use-after-free Read in reiserfs_fill_super fs 19 C error done 2 2058d 2057d 19/29 fixed on 2021/03/10 01:48
upstream KASAN: use-after-free Read in reiserfs_fill_super (2) fs 19 1 1694d 1690d 0/29 auto-closed as invalid on 2022/02/03 07:30
linux-4.14 KASAN: use-after-free Read in reiserfs_fill_super 19 C done 2 2028d 2028d 1/1 fixed on 2021/02/21 17:18
▶ ▼ Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/01/16 23:55 1h58m fix candidate upstream OK (0) job log
2024/11/30 11:27 14m bisect fix linux-6.1.y error job log

Sample crash report:
REISERFS (device loop0): journal params: device ram0, size 127, journal first block 18, max trans len 1024, max batch 900, max commit age 30, max trans age 30
REISERFS (device loop0): checking transaction log (ram0)
==================================================================
BUG: KASAN: use-after-free in init_inode fs/reiserfs/inode.c:1317 [inline]
BUG: KASAN: use-after-free in reiserfs_read_locked_inode+0x17a0/0x1dfc fs/reiserfs/inode.c:1566
Read of size 4 at addr ffff0000f1a00000 by task syz.0.17/4528

CPU: 0 PID: 4528 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/02/2026
Call trace:
 dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 __asan_report_load_n_noabort+0x28/0x34 mm/kasan/report_generic.c:361
 init_inode fs/reiserfs/inode.c:1317 [inline]
 reiserfs_read_locked_inode+0x17a0/0x1dfc fs/reiserfs/inode.c:1566
 reiserfs_fill_super+0xf18/0x1dbc fs/reiserfs/super.c:2071
 mount_bdev+0x264/0x35c fs/super.c:1443
 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601
 legacy_get_tree+0xd8/0x174 fs/fs_context.c:632
 vfs_get_tree+0x90/0x278 fs/super.c:1573
 do_new_mount+0x228/0x804 fs/namespace.c:3078
 path_mount+0x5ac/0xe6c fs/namespace.c:3408
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount fs/namespace.c:3606 [inline]
 __arm64_sys_mount+0x4a0/0x5a0 fs/namespace.c:3606
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the physical page:
page:000000007b896b0a refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x131a00
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003c68048 ffff00019f3ad060 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000f19fff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff0000f19fff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff0000f1a00000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff0000f1a00080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000f1a00100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
REISERFS warning (device loop0): vs-13075 reiserfs_read_locked_inode: dead inode read from disk [1 2 0x0 SD]. This is likely to be race with knfsd. Ignore
REISERFS warning (device loop0):  reiserfs_fill_super: corrupt root inode, run fsck

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/12 10:16 linux-6.1.y 090666d3cc90 d78ea535 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2026/07/12 09:07 linux-6.1.y 090666d3cc90 d78ea535 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2026/06/21 19:05 linux-6.1.y fdb6fcb41cc7 43bfcdb0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2026/06/14 20:05 linux-6.1.y 228da13e907e 1d2f3589 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2026/06/14 16:45 linux-6.1.y 228da13e907e 1d2f3589 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2024/10/20 14:36 linux-6.1.y 54d90d17e8ce cd6fc0a3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2026/06/14 01:54 linux-6.1.y 228da13e907e 1d2f3589 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2024/10/20 14:25 linux-6.1.y 54d90d17e8ce cd6fc0a3 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2024/10/22 03:33 linux-6.1.y 54d90d17e8ce f1e4447c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2024/10/22 03:33 linux-6.1.y 54d90d17e8ce f1e4447c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
2024/10/20 14:11 linux-6.1.y 54d90d17e8ce cd6fc0a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in reiserfs_fill_super
* Struck through repros no longer work on HEAD.