syzbot


KASAN: use-after-free Write in diWrite

Status: upstream: reported syz repro on 2022/10/19 03:08
Reported-by: syzbot+8b6aac199558389f3f80@syzkaller.appspotmail.com
First crash: 578d, last: 578d
Fix bisection: failed (error log, bisect log)
  
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Write in diWrite jfs C inconclusive 5 3d17h 23d 0/26 upstream: reported C repro on 2024/04/25 21:10
upstream UBSAN: array-index-out-of-bounds in diWrite jfs C error done 13 156d 576d 26/26 fixed on 2024/01/30 15:47

Sample crash report:
wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50
IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:377 [inline]
BUG: KASAN: slab-out-of-bounds in diWrite+0xbf2/0x13c0 fs/jfs/jfs_imap.c:764
Write of size 32 at addr ffff8880a636e260 by task syz-executor.4/10531

CPU: 0 PID: 10531 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report+0x8f/0xa0 mm/kasan/report.c:412
 memcpy+0x35/0x50 mm/kasan/kasan.c:303
 memcpy include/linux/string.h:377 [inline]
 diWrite+0xbf2/0x13c0 fs/jfs/jfs_imap.c:764
 txCommit+0x5f8/0x39e0 fs/jfs/jfs_txnmgr.c:1263
 jfs_create.part.0+0x76b/0x880 fs/jfs/namei.c:169
 jfs_create+0x3f/0x60 fs/jfs/namei.c:90
 lookup_open+0x893/0x1a20 fs/namei.c:3235
 do_last fs/namei.c:3327 [inline]
 path_openat+0x1094/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fc560c4d5a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc56039f168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc560d6e050 RCX: 00007fc560c4d5a9
RDX: 0000000000000000 RSI: 0000000000101042 RDI: 0000000020000040
RBP: 00007fc560ca8580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcad665e5f R14: 00007fc56039f300 R15: 0000000000022000

Allocated by task 4704:
 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
 getname_flags+0xce/0x590 fs/namei.c:140
 user_path_at_empty+0x2a/0x50 fs/namei.c:2609
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x248/0x7a0 fs/open.c:397
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 4704:
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x7f/0x260 mm/slab.c:3765
 putname+0xe1/0x120 fs/namei.c:261
 filename_lookup+0x3d0/0x5a0 fs/namei.c:2358
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x248/0x7a0 fs/open.c:397
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a636e9c0
 which belongs to the cache names_cache of size 4096
The buggy address is located 1888 bytes to the left of
 4096-byte region [ffff8880a636e9c0, ffff8880a636f9c0)
The buggy address belongs to the page:
page:ffffea000298db80 count:1 mapcount:0 mapping:ffff88823b843380 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffffea0002990c08 ffffea00023e4d08 ffff88823b843380
raw: 0000000000000000 ffff8880a636e9c0 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a636e100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a636e180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880a636e200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                       ^
 ffff8880a636e280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a636e300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/10/19 03:54 linux-4.19.y 3f8a27f9e27b b31320fc .config console log report syz [disk image] [vmlinux] [mounted in repro #1] [mounted in repro #2] ci2-linux-4-19 KASAN: slab-out-of-bounds Write in diWrite
2022/10/19 03:07 linux-4.19.y 3f8a27f9e27b b31320fc .config console log report info [disk image] [vmlinux] ci2-linux-4-19 KASAN: use-after-free Write in diWrite
* Struck through repros no longer work on HEAD.