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general protection fault in __mem_cgroup_free (2)

Status: closed as invalid on 2026/03/26 02:27
Subsystems: cgroups mm
[Documentation on labels]
First crash: 8d18h, last: 8d18h
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in __mem_cgroup_free cgroups mm 2 C 22 2910d 2922d 5/29 fixed on 2018/05/08 18:30

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc00000000f4: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x00000000000007a0-0x00000000000007a7]
CPU: 0 UID: 0 PID: 8377 Comm: syz.7.447 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__mem_cgroup_free+0xa1/0x200 mm/memcontrol.c:3940
Code: 49 01 ef 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 a0 e2 f6 ff 4d 8b 3f 4d 8d a7 a0 07 00 00 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 80 e2 f6 ff 49 8b 3c 24 48 85 ff
RSP: 0000:ffffc900038d7ad0 EFLAGS: 00010202
RAX: 00000000000000f4 RBX: 1ffffffff202488a RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88801ce8a940
RBP: ffff88801ce8b630 R08: ffffffff8e8b67e3 R09: 1ffffffff1d16cfc
R10: dffffc0000000000 R11: fffffbfff1d16cfd R12: 00000000000007a0
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f0f5bf7d6c0(0000) GS:ffff888125448000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc684f6b000 CR3: 000000007939a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 mem_cgroup_alloc mm/memcontrol.c:4028 [inline]
 mem_cgroup_css_alloc+0x480/0x1e70 mm/memcontrol.c:4040
 css_create kernel/cgroup/cgroup.c:5749 [inline]
 cgroup_apply_control_enable+0x5cd/0xd50 kernel/cgroup/cgroup.c:3328
 cgroup_mkdir+0xcfb/0xf50 kernel/cgroup/cgroup.c:5975
 kernfs_iop_mkdir+0x211/0x350 fs/kernfs/dir.c:1286
 vfs_mkdir+0x413/0x630 fs/namei.c:5255
 filename_mkdirat+0x285/0x510 fs/namei.c:5288
 __do_sys_mkdirat fs/namei.c:5309 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5306
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f5b19c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0f5bf7d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f0f5b415fa0 RCX: 00007f0f5b19c799
RDX: 00000000000001ff RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007f0f5b232c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0f5b416038 R14: 00007f0f5b415fa0 R15: 00007fff99c34518
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__mem_cgroup_free+0xa1/0x200 mm/memcontrol.c:3940
Code: 49 01 ef 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 a0 e2 f6 ff 4d 8b 3f 4d 8d a7 a0 07 00 00 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 80 e2 f6 ff 49 8b 3c 24 48 85 ff
RSP: 0000:ffffc900038d7ad0 EFLAGS: 00010202
RAX: 00000000000000f4 RBX: 1ffffffff202488a RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88801ce8a940
RBP: ffff88801ce8b630 R08: ffffffff8e8b67e3 R09: 1ffffffff1d16cfc
R10: dffffc0000000000 R11: fffffbfff1d16cfd R12: 00000000000007a0
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f0f5bf7d6c0(0000) GS:ffff888125548000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f39da5e92f8 CR3: 000000007939a000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	49 01 ef             	add    %rbp,%r15
   3:	4c 89 f8             	mov    %r15,%rax
   6:	48 c1 e8 03          	shr    $0x3,%rax
   a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
   f:	74 08                	je     0x19
  11:	4c 89 ff             	mov    %r15,%rdi
  14:	e8 a0 e2 f6 ff       	call   0xfff6e2b9
  19:	4d 8b 3f             	mov    (%r15),%r15
  1c:	4d 8d a7 a0 07 00 00 	lea    0x7a0(%r15),%r12
  23:	4c 89 e0             	mov    %r12,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 e7             	mov    %r12,%rdi
  34:	e8 80 e2 f6 ff       	call   0xfff6e2b9
  39:	49 8b 3c 24          	mov    (%r12),%rdi
  3d:	48 85 ff             	test   %rdi,%rdi

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/23 04:26 linux-next 785f0eb2f85d 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in __mem_cgroup_free
* Struck through repros no longer work on HEAD.