UBSAN: array-index-out-of-bounds in diNewExt

Status: fixed on 2024/03/04 11:50
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+f6d9772f9ef0ecdbdf6a@syzkaller.appspotmail.com
Fix commit: 58fca355ad37 drm/amd/display: Implement bounds check for stream encoder creation in DCN301
First crash: 937d, last: 937d
Fix bisection: fixed by (bisect log) :
commit efdd665ce1a1634b8c1dad5e7f6baaef3e131d0a
Author: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Date: Wed Feb 7 04:50:57 2024 +0000

  drm/amd/display: Implement bounds check for stream encoder creation in DCN301

  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2024/01/23 linux-6.1.y (ToT) 8fd7f4462453 C [report] UBSAN: array-index-out-of-bounds in diNewExt
2024/01/23 upstream (ToT) 7ed2632ec7d7 C Didn't crash
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream UBSAN: array-index-out-of-bounds in diNewExt jfs 15 syz, C inconclusive 31 930d 981d 25/29 fixed on 2024/01/30 15:47

Sample crash report:
loop0: detected capacity change from 0 to 32768
================================================================================
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_imap.c:2360:2
index 134217728 is out of range for type 'struct iagctl[128]'
CPU: 1 PID: 4221 Comm: syz-executor958 Not tainted 6.1.74-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 ubsan_epilogue lib/ubsan.c:151 [inline]
 __ubsan_handle_out_of_bounds+0xfc/0x148 lib/ubsan.c:282
 diNewExt+0x280c/0x2b44 fs/jfs/jfs_imap.c:2360
 diAllocExt fs/jfs/jfs_imap.c:1949 [inline]
 diAllocAG+0xa68/0x1b8c fs/jfs/jfs_imap.c:1666
 diAlloc+0x17c/0x15c4 fs/jfs/jfs_imap.c:1587
 ialloc+0x84/0x7c0 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x190/0xa0c fs/jfs/namei.c:225
 vfs_mkdir+0x334/0x4e4 fs/namei.c:4114
 do_mkdirat+0x220/0x510 fs/namei.c:4139
 __do_sys_mkdirat fs/namei.c:4154 [inline]
 __se_sys_mkdirat fs/namei.c:4152 [inline]
 __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4152
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 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
================================================================================
==================================================================
BUG: KASAN: use-after-free in diNewExt+0x2af0/0x2b44 fs/jfs/jfs_imap.c:2360
Read of size 4 at addr ffff000157e7802c by task syz-executor958/4221

CPU: 1 PID: 4221 Comm: syz-executor958 Not tainted 6.1.74-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x174/0x4c0 mm/kasan/report.c:395
 kasan_report+0xd4/0x130 mm/kasan/report.c:495
 __asan_report_load4_noabort+0x2c/0x38 mm/kasan/report_generic.c:350
 diNewExt+0x2af0/0x2b44 fs/jfs/jfs_imap.c:2360
 diAllocExt fs/jfs/jfs_imap.c:1949 [inline]
 diAllocAG+0xa68/0x1b8c fs/jfs/jfs_imap.c:1666
 diAlloc+0x17c/0x15c4 fs/jfs/jfs_imap.c:1587
 ialloc+0x84/0x7c0 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x190/0xa0c fs/jfs/namei.c:225
 vfs_mkdir+0x334/0x4e4 fs/namei.c:4114
 do_mkdirat+0x220/0x510 fs/namei.c:4139
 __do_sys_mkdirat fs/namei.c:4154 [inline]
 __se_sys_mkdirat fs/namei.c:4152 [inline]
 __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4152
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 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:000000009e7d2aa3 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x197e78
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc00055f9e08 fffffc00055f9e08 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff000157e77f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff000157e77f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff000157e78000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                  ^
 ffff000157e78080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff000157e78100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
================================================================================
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_imap.c:2361:2
index 134217728 is out of range for type 'struct iagctl[128]'
CPU: 1 PID: 4221 Comm: syz-executor958 Tainted: G    B              6.1.74-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 ubsan_epilogue lib/ubsan.c:151 [inline]
 __ubsan_handle_out_of_bounds+0xfc/0x148 lib/ubsan.c:282
 diNewExt+0x2840/0x2b44 fs/jfs/jfs_imap.c:2361
 diAllocExt fs/jfs/jfs_imap.c:1949 [inline]
 diAllocAG+0xa68/0x1b8c fs/jfs/jfs_imap.c:1666
 diAlloc+0x17c/0x15c4 fs/jfs/jfs_imap.c:1587
 ialloc+0x84/0x7c0 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x190/0xa0c fs/jfs/namei.c:225
 vfs_mkdir+0x334/0x4e4 fs/namei.c:4114
 do_mkdirat+0x220/0x510 fs/namei.c:4139
 __do_sys_mkdirat fs/namei.c:4154 [inline]
 __se_sys_mkdirat fs/namei.c:4152 [inline]
 __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4152
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 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
================================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/23 10:07 linux-6.1.y 8fd7f4462453 1c0ecc51 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 UBSAN: array-index-out-of-bounds in diNewExt
2024/01/23 09:15 linux-6.1.y 8fd7f4462453 1c0ecc51 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 UBSAN: array-index-out-of-bounds in diNewExt
* Struck through repros no longer work on HEAD.