syzbot

 sign-in | mailing list | source | docs
🐞 Open [121]
🐞 Fixed [23]
🐞 Invalid [252]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
💬 Send us feedback

KASAN: null-ptr-deref Read in ida_free

Status: fixed on 2023/06/16 14:10
Reported-by: syzbot+fbecd71010a6826c2e5f@syzkaller.appspotmail.com
Fix commit: 0af8fae81d8b fs: drop peer group ids under namespace lock
First crash: 618d, last: 547d
Cause bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: null-ptr-deref Read in ida_free media 1 1454d 1454d 0/28 auto-closed as invalid on 2021/04/09 00:32
upstream KASAN: null-ptr-deref Read in ida_free (2) usb C done 3 892d 893d 22/28 fixed on 2023/02/24 13:50
upstream KASAN: null-ptr-deref Read in ida_free (4) bluetooth C done done 29 346d 384d 25/28 fixed on 2024/02/14 16:17
upstream KASAN: null-ptr-deref Read in ida_free (3) fs C error 4 618d 614d 22/28 fixed on 2023/06/08 14:41
▶ ▼ Last patch testing requests (3)
Created Duration User Patch Repo Result
2023/04/05 14:13 16m tudordana@google.com https://github.com/ambarus/linux.git 275196365 OK log
2023/03/28 04:21 9m tudor.ambarus@linaro.org git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git v6.3-rc4 report log
2023/03/28 02:56 11m tudor.ambarus@linaro.org git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git v5.15.104 report log

Sample crash report:
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: null-ptr-deref in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
BUG: KASAN: null-ptr-deref in ida_free+0x1bc/0x3f0 lib/idr.c:511
Read of size 8 at addr 0000000000000000 by task syz-executor226/924

CPU: 1 PID: 924 Comm: syz-executor226 Not tainted 5.15.94-syzkaller-03204-g5448b2fda85f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
 __kasan_report mm/kasan/report.c:431 [inline]
 kasan_report+0x16f/0x1c0 mm/kasan/report.c:444
 kasan_check_range+0x293/0x2a0 mm/kasan/generic.c:189
 __kasan_check_read+0x11/0x20 mm/kasan/shadow.c:31
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 ida_free+0x1bc/0x3f0 lib/idr.c:511
 mnt_release_group_id fs/namespace.c:159 [inline]
 cleanup_group_ids fs/namespace.c:2048 [inline]
 do_mount_setattr fs/namespace.c:4115 [inline]
 __do_sys_mount_setattr fs/namespace.c:4299 [inline]
 __se_sys_mount_setattr+0xbcf/0x1cc0 fs/namespace.c:4258
 __x64_sys_mount_setattr+0xbf/0xd0 fs/namespace.c:4258
 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: 0033:0x7f226c33d919
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f226c2ef318 EFLAGS: 00000246 ORIG_RAX: 00000000000001ba
RAX: ffffffffffffffda RBX: 00007f226c3c53e8 RCX: 00007f226c33d919
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00007f226c3c53e0 R08: 0000000000000020 R09: 0000000000000000
R10: 0000000020000140 R11: 0000000000000246 R12: 0030656c69662f2e
R13: 00007ffd165c335f R14: 00007f226c2ef400 R15: 0000000000022000
 </TASK>
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 11fd41067 P4D 11fd41067 PUD 11fd40067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 924 Comm: syz-executor226 Tainted: G    B             5.15.94-syzkaller-03204-g5448b2fda85f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:214 [inline]
RIP: 0010:test_bit include/asm-generic/bitops/instrumented-non-atomic.h:135 [inline]
RIP: 0010:ida_free+0x1bf/0x3f0 lib/idr.c:511
Code: f1 fe 4c 89 e8 48 83 e0 01 0f 85 b9 00 00 00 41 89 de c1 eb 06 4d 8d 64 dd 00 4c 89 e7 be 08 00 00 00 e8 24 a7 32 ff 45 31 ff <4d> 0f a3 75 00 0f 92 c3 41 0f 92 c7 bf 02 00 00 00 44 89 fe e8 e8
RSP: 0018:ffffc90001037c80 EFLAGS: 00010046
RAX: ffff88810f448000 RBX: 0000000000000000 RCX: ffff88810f448000
RDX: 0000000000000000 RSI: 0000000000000096 RDI: 00000000ffffffff
RBP: ffffc90001037d70 R08: ffffffff8141cf1b R09: 0000000000000003
R10: fffffbfff0dcfe4c R11: dffffc0000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS:  00007f226c2ef700(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000011ad32000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 mnt_release_group_id fs/namespace.c:159 [inline]
 cleanup_group_ids fs/namespace.c:2048 [inline]
 do_mount_setattr fs/namespace.c:4115 [inline]
 __do_sys_mount_setattr fs/namespace.c:4299 [inline]
 __se_sys_mount_setattr+0xbcf/0x1cc0 fs/namespace.c:4258
 __x64_sys_mount_setattr+0xbf/0xd0 fs/namespace.c:4258
 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: 0033:0x7f226c33d919
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f226c2ef318 EFLAGS: 00000246 ORIG_RAX: 00000000000001ba
RAX: ffffffffffffffda RBX: 00007f226c3c53e8 RCX: 00007f226c33d919
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00007f226c3c53e0 R08: 0000000000000020 R09: 0000000000000000
R10: 0000000020000140 R11: 0000000000000246 R12: 0030656c69662f2e
R13: 00007ffd165c335f R14: 00007f226c2ef400 R15: 0000000000022000
 </TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 4ef4c7bf8225d212 ]---
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:214 [inline]
RIP: 0010:test_bit include/asm-generic/bitops/instrumented-non-atomic.h:135 [inline]
RIP: 0010:ida_free+0x1bf/0x3f0 lib/idr.c:511
Code: f1 fe 4c 89 e8 48 83 e0 01 0f 85 b9 00 00 00 41 89 de c1 eb 06 4d 8d 64 dd 00 4c 89 e7 be 08 00 00 00 e8 24 a7 32 ff 45 31 ff <4d> 0f a3 75 00 0f 92 c3 41 0f 92 c7 bf 02 00 00 00 44 89 fe e8 e8
RSP: 0018:ffffc90001037c80 EFLAGS: 00010046
RAX: ffff88810f448000 RBX: 0000000000000000 RCX: ffff88810f448000
RDX: 0000000000000000 RSI: 0000000000000096 RDI: 00000000ffffffff
RBP: ffffc90001037d70 R08: ffffffff8141cf1b R09: 0000000000000003
R10: fffffbfff0dcfe4c R11: dffffc0000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS:  00007f226c2ef700(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000011ad32000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	f1                   	icebp
   1:	fe 4c 89 e8          	decb   -0x18(%rcx,%rcx,4)
   5:	48 83 e0 01          	and    $0x1,%rax
   9:	0f 85 b9 00 00 00    	jne    0xc8
   f:	41 89 de             	mov    %ebx,%r14d
  12:	c1 eb 06             	shr    $0x6,%ebx
  15:	4d 8d 64 dd 00       	lea    0x0(%r13,%rbx,8),%r12
  1a:	4c 89 e7             	mov    %r12,%rdi
  1d:	be 08 00 00 00       	mov    $0x8,%esi
  22:	e8 24 a7 32 ff       	callq  0xff32a74b
  27:	45 31 ff             	xor    %r15d,%r15d
* 2a:	4d 0f a3 75 00       	bt     %r14,0x0(%r13) <-- trapping instruction
  2f:	0f 92 c3             	setb   %bl
  32:	41 0f 92 c7          	setb   %r15b
  36:	bf 02 00 00 00       	mov    $0x2,%edi
  3b:	44 89 fe             	mov    %r15d,%esi
  3e:	e8                   	.byte 0xe8
  3f:	e8                   	.byte 0xe8

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/03/26 01:58 android13-5.15-lts 5448b2fda85f fbf0499a .config strace log report syz C ci2-android-5-15 KASAN: null-ptr-deref Read in ida_free
2023/06/04 23:47 android13-5.15-lts 19c0ed55a470 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: null-ptr-deref Read in ida_free
* Struck through repros no longer work on HEAD.