Message-ID:
 <TYZPR06MB680739AC616DD61587BE380AD94C2@TYZPR06MB6807.apcprd06.prod.outlook.com>
Date: Tue, 22 Oct 2024 02:36:23 +0000
From: Ruan Bonan <bonan.ruan@...us.edu>
To: "jakub@...udflare.com" <jakub@...udflare.com>, "john.fastabend@...il.com"
	<john.fastabend@...il.com>, "davem@...emloft.net" <davem@...emloft.net>,
	"edumazet@...gle.com" <edumazet@...gle.com>, "kuba@...nel.org"
	<kuba@...nel.org>, "pabeni@...hat.com" <pabeni@...hat.com>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>, "bpf@...r.kernel.org"
	<bpf@...r.kernel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>
CC: "syzkaller@...glegroups.com" <syzkaller@...glegroups.com>
Subject: [BUG] general protection fault in sock_map_link_update_prog -
 Reproducible with Syzkaller

Hi there,

I used Syzkaller and found that there is KASAN: null-ptr-deref (general protection fault in sock_map_link_update_prog) in net/core/sock_map.c in v6.12.0-rc2, which also causes a KASAN: slab-use-after-free at the same time. It looks like a concurrency bug in the BPF related subsystems. The reproducer is available, and I have reproduced this bug with it manually. Currently I can only reproduce this bug with root privilege.

The detailed reports, config file, and reproducer program are attached in this e-mail. If you need further details, please let me know.

Bug report message:

```
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 0 UID: 0 PID: 640 Comm: syz-executor229 Not tainted 6.12.0-rc2-00667-g53bac8330865 #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:sock_map_progs net/core/sock_map.c:1449 [inline]
RIP: 0010:sock_map_prog_link_lookup net/core/sock_map.c:1464 [inline]
RIP: 0010:sock_map_link_update_prog+0x17a/0x450 net/core/sock_map.c:1756
Code: 8b 6c 24 68 49 8d 5c 24 70 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 a3 02 00 00 8b 2b 49 8d 5d 18 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 a6 02 00 00 8b 1b 48 89 df 48 c7 c6 10
RSP: 0018:ffff888003837cc8 EFLAGS: 00010206
RAX: 0000000000000003 RBX: 0000000000000018 RCX: 0000000000000000
RDX: ffff888006b95400 RSI: 000000000000000d RDI: ffff888005f91a68
RBP: 0000000000000005 R08: ffffffff99e031af R09: 1ffffffff33c0635
R10: dffffc0000000000 R11: fffffbfff33c0636 R12: ffff888005f91a00
R13: 0000000000000000 R14: ffffc90000e55000 R15: dffffc0000000000
FS:  00007f4f04921640(0000) GS:ffff88806cc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4f049bf7a0 CR3: 0000000006446000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
link_update+0x726/0x8a0 kernel/bpf/syscall.c:5328
__sys_bpf+0x5d5/0x7f0 kernel/bpf/syscall.c:5707
__do_sys_bpf kernel/bpf/syscall.c:5741 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5739 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5739
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xe4/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4f0497d73d
Code: c3 e8 37 20 00 00 0f 1f 80 00 00 00 00 f3 0f 1e fa 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4f049211a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f4f04a18228 RCX: 00007f4f0497d73d
RDX: 0000000000000010 RSI: 00000000200004c0 RDI: 000000000000001d
RBP: 00007f4f04a18220 R08: 00007f4f04921640 R09: 00007f4f04921640
R10: 00007f4f04921640 R11: 0000000000000246 R12: 00007f4f04a1822c
R13: 00007f4f049e3074 R14: 656c6c616b7a7973 R15: 00007f4f04901000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:sock_map_progs net/core/sock_map.c:1449 [inline]
RIP: 0010:sock_map_prog_link_lookup net/core/sock_map.c:1464 [inline]
RIP: 0010:sock_map_link_update_prog+0x17a/0x450 net/core/sock_map.c:1756
Code: 8b 6c 24 68 49 8d 5c 24 70 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 a3 02 00 00 8b 2b 49 8d 5d 18 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 a6 02 00 00 8b 1b 48 89 df 48 c7 c6 10
RSP: 0018:ffff888003837cc8 EFLAGS: 00010206
RAX: 0000000000000003 RBX: 0000000000000018 RCX: 0000000000000000
RDX: ffff888006b95400 RSI: 000000000000000d RDI: ffff888005f91a68
RBP: 0000000000000005 R08: ffffffff99e031af R09: 1ffffffff33c0635
R10: dffffc0000000000 R11: fffffbfff33c0636 R12: ffff888005f91a00
R13: 0000000000000000 R14: ffffc90000e55000 R15: dffffc0000000000
FS:  00007f4f04921640(0000) GS:ffff88806cc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4f049bf7a0 CR3: 0000000006446000 CR4: 0000000000750ef0
PKRU: 55555554
==================================================================
BUG: KASAN: slab-use-after-free in owner_on_cpu include/linux/sched.h:2171 [inline]
BUG: KASAN: slab-use-after-free in mutex_can_spin_on_owner kernel/locking/mutex.c:409 [inline]
BUG: KASAN: slab-use-after-free in mutex_optimistic_spin kernel/locking/mutex.c:452 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:612 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock+0xc63/0xcd0 kernel/locking/mutex.c:752
Read of size 4 at addr ffff888006b95434 by task syz-executor229/644

CPU: 0 UID: 0 PID: 644 Comm: syz-executor229 Tainted: G      D            6.12.0-rc2-00667-g53bac8330865 #6
Tainted: [D]=DIE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x14b/0x1c0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x171/0x750 mm/kasan/report.c:488
kasan_report+0xd2/0x110 mm/kasan/report.c:601
owner_on_cpu include/linux/sched.h:2171 [inline]
mutex_can_spin_on_owner kernel/locking/mutex.c:409 [inline]
mutex_optimistic_spin kernel/locking/mutex.c:452 [inline]
__mutex_lock_common kernel/locking/mutex.c:612 [inline]
__mutex_lock+0xc63/0xcd0 kernel/locking/mutex.c:752
sock_map_link_create+0x2b6/0x5b0 net/core/sock_map.c:1861
link_create+0x513/0x890 kernel/bpf/syscall.c:5215
__sys_bpf+0x49c/0x7f0 kernel/bpf/syscall.c:5704
__do_sys_bpf kernel/bpf/syscall.c:5741 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5739 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5739
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xe4/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4f0497d73d
Code: c3 e8 37 20 00 00 0f 1f 80 00 00 00 00 f3 0f 1e fa 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4f049211a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f4f04a18228 RCX: 00007f4f0497d73d
RDX: 0000000000000010 RSI: 0000000020000200 RDI: 000000000000001c
RBP: 00007f4f04a18220 R08: 00007f4f04921640 R09: 00007f4f04921640
R10: 00007f4f04921640 R11: 0000000000000246 R12: 00007f4f04a1822c
R13: 00007f4f049e3074 R14: 656c6c616b7a7973 R15: 00007f4f04901000
</TASK>

Allocated by task 639:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x2f/0x70 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:319 [inline]
__kasan_slab_alloc+0x4b/0x60 mm/kasan/common.c:345
kasan_slab_alloc include/linux/kasan.h:247 [inline]
slab_post_alloc_hook mm/slub.c:4085 [inline]
slab_alloc_node mm/slub.c:4134 [inline]
kmem_cache_alloc_node_noprof+0x139/0x2e0 mm/slub.c:4186
alloc_task_struct_node kernel/fork.c:180 [inline]
dup_task_struct+0xb2/0x7d0 kernel/fork.c:1107
copy_process+0x5fa/0x3c30 kernel/fork.c:2203
kernel_clone+0x20c/0x800 kernel/fork.c:2784
__do_sys_clone3 kernel/fork.c:3088 [inline]
__se_sys_clone3 kernel/fork.c:3067 [inline]
__x64_sys_clone3+0x2e2/0x360 kernel/fork.c:3067
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xe4/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 0:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x2f/0x70 mm/kasan/common.c:68
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x37/0x50 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:2342 [inline]
slab_free mm/slub.c:4579 [inline]
kmem_cache_free+0x179/0x3e0 mm/slub.c:4681
put_task_struct include/linux/sched/task.h:144 [inline]
delayed_put_task_struct+0x114/0x2c0 kernel/exit.c:228
rcu_do_batch kernel/rcu/tree.c:2567 [inline]
rcu_core+0xcb1/0x19d0 kernel/rcu/tree.c:2823
handle_softirqs+0x24e/0x840 kernel/softirq.c:554
__do_softirq kernel/softirq.c:588 [inline]
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xc2/0x160 kernel/softirq.c:637
irq_exit_rcu+0x9/0x20 kernel/softirq.c:649
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline]
sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1037
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

Last potentially related work creation:
kasan_save_stack+0x2f/0x50 mm/kasan/common.c:47
__kasan_record_aux_stack mm/kasan/generic.c:541 [inline]
kasan_record_aux_stack_noalloc+0x99/0xb0 mm/kasan/generic.c:551
__call_rcu_common kernel/rcu/tree.c:3086 [inline]
call_rcu+0xd9/0xab0 kernel/rcu/tree.c:3190
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x189e/0x25c0 kernel/sched/core.c:6682
schedule_idle+0x52/0x90 kernel/sched/core.c:6800
do_idle+0x533/0x590 kernel/sched/idle.c:354
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:424
rest_init+0x2e1/0x300 init/main.c:747
start_kernel+0x47b/0x510 init/main.c:1105
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:507
x86_64_start_kernel+0x79/0x80 arch/x86/kernel/head64.c:488
common_startup_64+0x12c/0x137

The buggy address belongs to the object at ffff888006b95400
which belongs to the cache task_struct of size 6856
The buggy address is located 52 bytes inside of
freed 6856-byte region [ffff888006b95400, ffff888006b96ec8)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6b90
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88800a08f201
flags: 0x100000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0100000000000040 ffff8880011a03c0 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000040004 00000001f5000000 ffff88800a08f201
head: 0100000000000040 ffff8880011a03c0 dead000000000122 0000000000000000
head: 0000000000000000 0000000000040004 00000001f5000000 ffff88800a08f201
head: 0100000000000003 ffffea00001ae401 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff888006b95300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888006b95380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888006b95400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
ffff888006b95480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888006b95500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0: 8b 6c 24 68          mov    0x68(%rsp),%ebp
   4: 49 8d 5c 24 70       lea    0x70(%r12),%rbx
   9: 48 89 d8             mov    %rbx,%rax
   c: 48 c1 e8 03          shr    $0x3,%rax
  10: 42 0f b6 04 38       movzbl (%rax,%r15,1),%eax
  15: 84 c0                test   %al,%al
  17: 0f 85 a3 02 00 00    jne    0x2c0
  1d: 8b 2b                mov    (%rbx),%ebp
  1f: 49 8d 5d 18          lea    0x18(%r13),%rbx
  23: 48 89 d8             mov    %rbx,%rax
  26: 48 c1 e8 03          shr    $0x3,%rax
* 2a: 42 0f b6 04 38       movzbl (%rax,%r15,1),%eax <-- trapping instruction
  2f: 84 c0                test   %al,%al
  31: 0f 85 a6 02 00 00    jne    0x2dd
  37: 8b 1b                mov    (%rbx),%ebx
  39: 48 89 df             mov    %rbx,%rdi
  3c: 48                   rex.W
  3d: c7                   .byte 0xc7
  3e: c6                   (bad)
  3f: 10                   .byte 0x10
```

Thanks and best regards,
Bonan

Content of type "text/html" skipped

Download attachment "repro.cprog" of type "application/octet-stream" (9719 bytes)

Download attachment "repro_config" of type "application/octet-stream" (150140 bytes)

View attachment "repro.log" of type "text/plain" (18727 bytes)

Download attachment "repro.prog" of type "application/octet-stream" (1115 bytes)

Download attachment "repro.report" of type "application/octet-stream" (11109 bytes)

Download attachment "other_details.zip" of type "application/zip" (58392 bytes)

Powered by blists - more mailing lists