syzbot


KASAN: slab-out-of-bounds Read in jfs_readdir

Status: upstream: reported on 2023/01/12 07:34
Subsystems: jfs
[Documentation on labels]
Reported-by: syzbot+d26e428dbaf1367b4172@syzkaller.appspotmail.com
First crash: 463d, last: 463d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in jfs_readdir jfs C error done 17 102d 463d 26/26 fixed on 2024/03/20 11:33
linux-4.19 KASAN: slab-out-of-bounds Read in jfs_readdir jfs 2 463d 463d 0/1 upstream: reported on 2023/01/12 07:27
linux-5.15 UBSAN: array-index-out-of-bounds in jfs_readdir origin:upstream C 15 2d13h 18d 0/3 upstream: reported C repro on 2024/04/01 00:20
linux-6.1 UBSAN: array-index-out-of-bounds in jfs_readdir C 27 5d03h 18d 0/3 upstream: reported C repro on 2024/04/01 00:16
upstream UBSAN: array-index-out-of-bounds in jfs_readdir jfs C inconclusive 24 10d 18d 0/26 upstream: reported C repro on 2024/04/01 14:07

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in jfs_readdir+0x2eaa/0x36c0 fs/jfs/jfs_dtree.c:3199
Read of size 1 at addr ffff88804a5a80ad by task syz-executor.5/10533

CPU: 0 PID: 10533 Comm: syz-executor.5 Not tainted 4.14.302-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load1_noabort+0x68/0x70 mm/kasan/report.c:427
 jfs_readdir+0x2eaa/0x36c0 fs/jfs/jfs_dtree.c:3199
 iterate_dir+0x478/0x5e0 fs/readdir.c:54
 SYSC_getdents64 fs/readdir.c:358 [inline]
 SyS_getdents64+0x125/0x230 fs/readdir.c:339
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7f50a4fa40c9
RSP: 002b:00007f50a3516168 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f50a50c3f80 RCX: 00007f50a4fa40c9
RDX: 00000000000000c5 RSI: 0000000020000200 RDI: 0000000000000004
RBP: 00007f50a4fffae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffcd99ed8f R14: 00007f50a3516300 R15: 0000000000022000

Allocated by task 10533:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
 kmem_cache_alloc+0x124/0x3c0 mm/slab.c:3552
 jfs_alloc_inode+0x18/0x50 fs/jfs/super.c:118
 alloc_inode+0x5d/0x170 fs/inode.c:209
 iget_locked+0x151/0x400 fs/inode.c:1126
 jfs_iget+0x1e/0x480 fs/jfs/inode.c:41
 jfs_fill_super+0x5f7/0xab0 fs/jfs/super.c:613
 mount_bdev+0x2b3/0x360 fs/super.c:1134
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2572 [inline]
 do_mount+0xe65/0x2a30 fs/namespace.c:2905
 SYSC_mount fs/namespace.c:3121 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3098
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff88804a5a8180
 which belongs to the cache jfs_ip of size 1952
The buggy address is located 211 bytes to the left of
 1952-byte region [ffff88804a5a8180, ffff88804a5a8920)
The buggy address belongs to the page:
page:ffffea0001296a00 count:1 mapcount:0 mapping:ffff88804a5a8180 index:0xffff88804a5a8fff
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffff88804a5a8180 ffff88804a5a8fff 0000000100000001
raw: ffffea0001295360 ffff8880b13cc048 ffff888238c32c80 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88804a5a7f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88804a5a8000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88804a5a8080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff88804a5a8100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88804a5a8180: 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
2023/01/12 07:34 linux-4.14.y c4215ee4771b 96166539 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 KASAN: slab-out-of-bounds Read in jfs_readdir
* Struck through repros no longer work on HEAD.