general protection fault in refill_obj_stock

[Ubisectech Sirius]

Hello.
We are Ubisectech Sirius Team, the vulnerability lab of China ValiantSec. Recently, our team has discovered a issue in Linux kernel 6.7. Attached to the email were a PoC file of the issue.

Stack dump:
general protection fault, probably for non-canonical address 0xdffffc0000001cc6: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: probably user-memory-access in range [0x000000000000e630-0x000000000000e637]
CPU: 0 PID: 8041 Comm: systemd-udevd Not tainted 6.7.0 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:__ref_is_percpu include/linux/percpu-refcount.h:174 [inline]
RIP: 0010:percpu_ref_get_many include/linux/percpu-refcount.h:204 [inline]
RIP: 0010:percpu_ref_get include/linux/percpu-refcount.h:222 [inline]
RIP: 0010:obj_cgroup_get include/linux/memcontrol.h:810 [inline]
RIP: 0010:refill_obj_stock+0x135/0x500 mm/memcontrol.c:3535
Code: c7 c7 60 9f 3a 8d e8 fa ca 81 ff e8 d5 4e b2 08 5a 85 c0 0f 85 52 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 86 03 00 00 48 8b 45 00 a8 03 0f 85 76 02 00 00
RSP: 0018:ffffc900088bf898 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 00000000000380a0 RCX: 1ffff92001117edd
RDX: 0000000000001cc6 RSI: 0000000000000001 RDI: ffffffff8cddfa60
RBP: 000000000000e633 R08: 0000000000000000 R09: fffffbfff27147e0
R10: ffffffff938a3f07 R11: 0000000000000000 R12: 0000000000000148
R13: 0000000000000200 R14: ffff88802c6380a0 R15: ffff88802c6380e0
FS:  00007f774934e8c0(0000) GS:ffff88802c600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555566127e8 CR3: 0000000048fe8000 CR4: 0000000000750ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 memcg_slab_free_hook+0x157/0x2c0
 slab_free_hook mm/slub.c:2075 [inline]
 slab_free mm/slub.c:4280 [inline]
 kmem_cache_free+0xe1/0x350 mm/slub.c:4344
 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:1159
 __kfree_skb net/core/skbuff.c:1217 [inline]
 consume_skb net/core/skbuff.c:1432 [inline]
 consume_skb+0xdf/0x170 net/core/skbuff.c:1426
 netlink_recvmsg+0x5cb/0xf10 net/netlink/af_netlink.c:1983
 sock_recvmsg_nosec net/socket.c:1046 [inline]
 sock_recvmsg+0x1de/0x240 net/socket.c:1068
 ____sys_recvmsg+0x216/0x670 net/socket.c:2803
 ___sys_recvmsg+0xff/0x190 net/socket.c:2845
 __sys_recvmsg+0xfb/0x1d0 net/socket.c:2875
 current_top_of_stack arch/x86/include/asm/processor.h:532 [inline]
 on_thread_stack arch/x86/include/asm/processor.h:537 [inline]
 arch_enter_from_user_mode arch/x86/include/asm/entry-common.h:41 [inline]
 enter_from_user_mode include/linux/entry-common.h:108 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x43/0x120 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f7749601d73
Code: 8b 15 59 a2 00 00 f7 d8 64 89 02 b8 ff ff ff ff eb b7 0f 1f 44 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 2f 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 55 c3 0f 1f 40 00 48 83 ec 28 89 54 24 1c 48
RSP: 002b:00007fff81586858 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007fff81588a20 RCX: 00007f7749601d73
RDX: 0000000000000000 RSI: 00007fff815868f0 RDI: 000000000000000f
RBP: 00007fff815869d0 R08: 00000000000046d4 R09: 00007fff815e5080
R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000
R13: 000055824edb2ef0 R14: 0000000000000100 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__ref_is_percpu include/linux/percpu-refcount.h:174 [inline]
RIP: 0010:percpu_ref_get_many include/linux/percpu-refcount.h:204 [inline]
RIP: 0010:percpu_ref_get include/linux/percpu-refcount.h:222 [inline]
RIP: 0010:obj_cgroup_get include/linux/memcontrol.h:810 [inline]
RIP: 0010:refill_obj_stock+0x135/0x500 mm/memcontrol.c:3535
Code: c7 c7 60 9f 3a 8d e8 fa ca 81 ff e8 d5 4e b2 08 5a 85 c0 0f 85 52 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 86 03 00 00 48 8b 45 00 a8 03 0f 85 76 02 00 00
RSP: 0018:ffffc900088bf898 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 00000000000380a0 RCX: 1ffff92001117edd
RDX: 0000000000001cc6 RSI: 0000000000000001 RDI: ffffffff8cddfa60
RBP: 000000000000e633 R08: 0000000000000000 R09: fffffbfff27147e0
R10: ffffffff938a3f07 R11: 0000000000000000 R12: 0000000000000148
R13: 0000000000000200 R14: ffff88802c6380a0 R15: ffff88802c6380e0
FS:  00007f774934e8c0(0000) GS:ffff88802c600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555566127e8 CR3: 0000000048fe8000 CR4: 0000000000750ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
----------------
Code disassembly (best guess):
   0:   c7 c7 60 9f 3a 8d       mov    $0x8d3a9f60,%edi
   6:   e8 fa ca 81 ff          call   0xff81cb05
   b:   e8 d5 4e b2 08          call   0x8b24ee5
  10:   5a                      pop    %rdx
  11:   85 c0                   test   %eax,%eax
  13:   0f 85 52 02 00 00       jne    0x26b
  19:   48 b8 00 00 00 00 00    movabs $0xdffffc0000000000,%rax
  20:   fc ff df
  23:   48 89 ea                mov    %rbp,%rdx
  26:   48 c1 ea 03             shr    $0x3,%rdx
* 2a:   80 3c 02 00             cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:   0f 85 86 03 00 00       jne    0x3ba
  34:   48 8b 45 00             mov    0x0(%rbp),%rax
  38:   a8 03                   test   $0x3,%al
  3a:   0f 85 76 02 00 00       jne    0x2b6


Thank you for taking the time to read this email and we look forward to working with you further.

Attachment: poc.c
Description: Binary data