syzbot


general protection fault in find_mergeable_anon_vma

Status: upstream: reported on 2024/12/09 11:20
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+2d788f4f7cb660dac4b7@syzkaller.appspotmail.com
Fix commit: fork: avoid inappropriate uprobe access to invalid mm
Patched on: [ci-upstream-linux-next-kasan-gce-root], missing on: [ci-qemu-gce-upstream-auto ci-qemu-native-arm64-kvm ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb]
First crash: 17d, last: 17d
Discussions (3)
Title Replies (including bot) Last reply
[PATCH v2] fork: avoid inappropriate uprobe access to invalid mm 4 (4) 2024/12/10 21:43
[PATCH] fork: avoid inappropriate uprobe access to invalid mm 1 (1) 2024/12/10 16:31
[syzbot] [mm?] general protection fault in find_mergeable_anon_vma 13 (14) 2024/12/10 15:18

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000080: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000400-0x0000000000000407]
CPU: 0 UID: 0 PID: 5319 Comm: syz.0.0 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:anon_vma_compatible mm/vma.c:1804 [inline]
RIP: 0010:reusable_anon_vma mm/vma.c:1837 [inline]
RIP: 0010:find_mergeable_anon_vma+0x1e4/0x8f0 mm/vma.c:1863
Code: 00 00 00 00 fc ff df 41 80 3c 06 00 74 08 4c 89 ff e8 10 39 10 00 4d 8b 37 4d 89 ec 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df <41> 80 3c 04 00 74 08 4c 89 ef e8 ed 38 10 00 49 8b 5d 00 4c 89 f7
RSP: 0018:ffffc9000d3df500 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: ffffc9000d3df540 RCX: ffff88801cf80000
RDX: 0000000000000000 RSI: ffffffff900062a0 RDI: 0000000000000000
RBP: ffffc9000d3df610 R08: 0000000000000005 R09: ffffffff8bc6b642
R10: 0000000000000003 R11: ffff88801cf80000 R12: 0000000000000080
R13: 0000000000000406 R14: 0000000021000000 R15: ffff8880120d4ca0
FS:  00007f137f7e86c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000140 CR3: 0000000040256000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __anon_vma_prepare+0xd9/0x4a0 mm/rmap.c:199
 anon_vma_prepare include/linux/rmap.h:164 [inline]
 uprobe_write_opcode+0x1a95/0x2d80 kernel/events/uprobes.c:516
 install_breakpoint+0x4fc/0x660 kernel/events/uprobes.c:1135
 register_for_each_vma+0xa08/0xc50 kernel/events/uprobes.c:1275
 uprobe_register+0x811/0x970 kernel/events/uprobes.c:1384
 bpf_uprobe_multi_link_attach+0xaca/0xdd0 kernel/trace/bpf_trace.c:3442
 link_create+0x6d7/0x870 kernel/bpf/syscall.c:5399
 __sys_bpf+0x4bc/0x810 kernel/bpf/syscall.c:5860
 __do_sys_bpf kernel/bpf/syscall.c:5897 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5895 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5895
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f137e97ff19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f137f7e8058 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f137eb46080 RCX: 00007f137e97ff19
RDX: 000000000000003c RSI: 00000000200012c0 RDI: 000000000000001c
RBP: 00007f137e9f3986 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f137eb46080 R15: 00007fff36be56b8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:anon_vma_compatible mm/vma.c:1804 [inline]
RIP: 0010:reusable_anon_vma mm/vma.c:1837 [inline]
RIP: 0010:find_mergeable_anon_vma+0x1e4/0x8f0 mm/vma.c:1863
Code: 00 00 00 00 fc ff df 41 80 3c 06 00 74 08 4c 89 ff e8 10 39 10 00 4d 8b 37 4d 89 ec 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df <41> 80 3c 04 00 74 08 4c 89 ef e8 ed 38 10 00 49 8b 5d 00 4c 89 f7
RSP: 0018:ffffc9000d3df500 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: ffffc9000d3df540 RCX: ffff88801cf80000
RDX: 0000000000000000 RSI: ffffffff900062a0 RDI: 0000000000000000
RBP: ffffc9000d3df610 R08: 0000000000000005 R09: ffffffff8bc6b642
R10: 0000000000000003 R11: ffff88801cf80000 R12: 0000000000000080
R13: 0000000000000406 R14: 0000000021000000 R15: ffff8880120d4ca0
FS:  00007f137f7e86c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002240 CR3: 0000000040256000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 6 bytes skipped:
   0:	df 41 80             	filds  -0x80(%rcx)
   3:	3c 06                	cmp    $0x6,%al
   5:	00 74 08 4c          	add    %dh,0x4c(%rax,%rcx,1)
   9:	89 ff                	mov    %edi,%edi
   b:	e8 10 39 10 00       	call   0x103920
  10:	4d 8b 37             	mov    (%r15),%r14
  13:	4d 89 ec             	mov    %r13,%r12
  16:	49 c1 ec 03          	shr    $0x3,%r12
  1a:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  21:	fc ff df
* 24:	41 80 3c 04 00       	cmpb   $0x0,(%r12,%rax,1) <-- trapping instruction
  29:	74 08                	je     0x33
  2b:	4c 89 ef             	mov    %r13,%rdi
  2e:	e8 ed 38 10 00       	call   0x103920
  33:	49 8b 5d 00          	mov    0x0(%r13),%rbx
  37:	4c 89 f7             	mov    %r14,%rdi

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/04 14:30 upstream feffde684ac2 b50eb251 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in find_mergeable_anon_vma
* Struck through repros no longer work on HEAD.