syzbot


KASAN: out-of-bounds Read in reiserfs_readdir_inode

Status: upstream: reported C repro on 2023/04/30 22:45
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+de4c26fe8bf1b9b69e3a@syzkaller.appspotmail.com
First crash: 416d, last: 18d
Bug presence (1)
Date Name Commit Repro Result
2023/05/18 upstream (ToT) 4d6d4c7f541d C [report] KASAN: use-after-free Read in reiserfs_readdir_inode
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: unable to handle kernel paging request in reiserfs_readdir_inode reiserfs C error done 11 165d 531d 26/27 fixed on 2024/02/21 18:23
linux-6.1 KASAN: use-after-free Read in reiserfs_readdir_inode origin:upstream C 1 33d 409d 0/3 upstream: reported C repro on 2023/05/07 23:16
Fix bisection attempts (11)
Created Duration User Patch Repo Result
2024/06/01 21:15 1h49m bisect fix linux-5.15.y job log (0) log
2024/04/29 21:53 2h02m bisect fix linux-5.15.y job log (0) log
2024/03/29 09:26 3h42m bisect fix linux-5.15.y job log (0) log
2024/02/28 06:10 58m bisect fix linux-5.15.y job log (0) log
2024/01/19 10:56 1h03m bisect fix linux-5.15.y job log (0) log
2023/12/19 04:52 2h02m bisect fix linux-5.15.y job log (0) log
2023/11/18 22:33 1h19m bisect fix linux-5.15.y job log (0) log
2023/10/18 01:29 1h37m bisect fix linux-5.15.y job log (0) log
2023/09/14 21:02 1h20m bisect fix linux-5.15.y job log (0) log
2023/07/01 10:55 39m bisect fix linux-5.15.y job log (0) log
2023/06/01 04:12 33m bisect fix linux-5.15.y job log (0) log

Sample crash report:
REISERFS (device loop0): journal params: device loop0, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using r5 hash to sort names
==================================================================
BUG: KASAN: out-of-bounds in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: out-of-bounds in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
BUG: KASAN: out-of-bounds in test_bit_le include/asm-generic/bitops/le.h:85 [inline]
BUG: KASAN: out-of-bounds in reiserfs_readdir_inode+0x5d8/0x14d0 fs/reiserfs/dir.c:147
Read of size 8 at addr ffff888071adb000 by task syz-executor204/3499

CPU: 0 PID: 3499 Comm: syz-executor204 Not tainted 5.15.109-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 kasan_check_range+0x27e/0x290 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 test_bit_le include/asm-generic/bitops/le.h:85 [inline]
 reiserfs_readdir_inode+0x5d8/0x14d0 fs/reiserfs/dir.c:147
 iterate_dir+0x224/0x570
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64+0x209/0x4f0 fs/readdir.c:354
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f5b357182e9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 d1 17 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcdb0866f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007ffcdb086748 RCX: 00007f5b357182e9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007ffcdb086820 R09: 00007ffcdb086820
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcdb086740
R13: 00007ffcdb086820 R14: 431bde82d7b634db R15: 00007ffcdb086720
 </TASK>

The buggy address belongs to the page:
page:ffffea0001c6b6c0 refcount:1 mapcount:1 mapping:0000000000000000 index:0x7fffffff4 pfn:0x71adb
memcg:ffff888011e5c000
anon flags: 0xfff00000080014(uptodate|lru|swapbacked|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000080014 ffffea0001c9ccc8 ffffea0001c6b708 ffff888024f13bb1
raw: 00000007fffffff4 0000000000000000 0000000100000000 ffff888011e5c000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x1100cca(GFP_HIGHUSER_MOVABLE), pid 2962, ts 60302495732, free_ts 10649780676
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5421
 alloc_pages_vma+0x39a/0x800 mm/mempolicy.c:2146
 wp_page_copy+0x26c/0x2000 mm/memory.c:3016
 handle_pte_fault mm/memory.c:4626 [inline]
 __handle_mm_fault mm/memory.c:4743 [inline]
 handle_mm_fault+0x2a3d/0x5950 mm/memory.c:4841
 do_user_addr_fault arch/x86/mm/fault.c:1397 [inline]
 handle_page_fault arch/x86/mm/fault.c:1485 [inline]
 exc_page_fault+0x271/0x740 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 free_contig_range+0x95/0xf0 mm/page_alloc.c:9340
 destroy_args+0xfe/0x97f mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x40d/0x462 mm/debug_vm_pgtable.c:1331
 do_one_initcall+0x22b/0x7a0 init/main.c:1306
 do_initcall_level+0x157/0x207 init/main.c:1379
 do_initcalls+0x49/0x86 init/main.c:1395
 kernel_init_freeable+0x43c/0x5c5 init/main.c:1619
 kernel_init+0x19/0x290 init/main.c:1510
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Memory state around the buggy address:
 ffff888071adaf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888071adaf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888071adb000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff888071adb080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888071adb100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/30 22:44 linux-5.15.y f48aeeaaa64c 62df2017 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan KASAN: out-of-bounds Read in reiserfs_readdir_inode
* Struck through repros no longer work on HEAD.