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general protection fault in rds_tcp_tc_info

Status: closed as invalid on 2026/04/30 15:35
Subsystems: rds
[Documentation on labels]
First crash: 89d, last: 89d

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 1 UID: 0 PID: 7626 Comm: syz.5.500 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:rds_tcp_tc_info+0x1a3/0x580 net/rds/tcp.c:248
Code: bc 24 98 fe ff ff 4c 89 f8 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 7b 75 c0 f7 4d 8b 3f 49 83 c7 18 4c 89 f8 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 ff e8 5e 75 c0 f7 4d 8b 3f 49 8d bf 98
RSP: 0018:ffffc9000450fb80 EFLAGS: 00010206
RAX: 0000000000000003 RBX: ffff88803e5a19d8 RCX: 0000000000080000
RDX: ffffc9001da9e000 RSI: 0000000000001b5d RDI: 0000000000001b5e
RBP: ffffc9000450fc70 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1ed4bb7 R12: ffff88803e5a1bc8
R13: 1ffff11007cb433b R14: dffffc0000000000 R15: 0000000000000018
FS:  00007f80baac96c0(0000) GS:ffff888126439000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3371dff8 CR3: 000000003dd3e000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rds_info_getsockopt+0x2e9/0x400 net/rds/info.c:218
 do_sock_getsockopt+0x2d3/0x3f0 net/socket.c:2383
 __sys_getsockopt net/socket.c:2412 [inline]
 __do_sys_getsockopt net/socket.c:2419 [inline]
 __se_sys_getsockopt net/socket.c:2416 [inline]
 __x64_sys_getsockopt+0x1aa/0x250 net/socket.c:2416
 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: 0033:0x7f80bccdc799
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:00007f80baac9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007f80bcf56270 RCX: 00007f80bccdc799
RDX: 0000000000002717 RSI: 0000200000000114 RDI: 0000000000000007
RBP: 00007f80bcd72c99 R08: 0000200000000000 R09: 0000000000000000
R10: 0000200000019580 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f80bcf56308 R14: 00007f80bcf56270 R15: 00007ffd514f1918
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:rds_tcp_tc_info+0x1a3/0x580 net/rds/tcp.c:248
Code: bc 24 98 fe ff ff 4c 89 f8 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 7b 75 c0 f7 4d 8b 3f 49 83 c7 18 4c 89 f8 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 ff e8 5e 75 c0 f7 4d 8b 3f 49 8d bf 98
RSP: 0018:ffffc9000450fb80 EFLAGS: 00010206
RAX: 0000000000000003 RBX: ffff88803e5a19d8 RCX: 0000000000080000
RDX: ffffc9001da9e000 RSI: 0000000000001b5d RDI: 0000000000001b5e
RBP: ffffc9000450fc70 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1ed4bb7 R12: ffff88803e5a1bc8
R13: 1ffff11007cb433b R14: dffffc0000000000 R15: 0000000000000018
FS:  00007f80baac96c0(0000) GS:ffff888126439000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3371dff8 CR3: 000000003dd3e000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	bc 24 98 fe ff       	mov    $0xfffe9824,%esp
   5:	ff 4c 89 f8          	decl   -0x8(%rcx,%rcx,4)
   9:	48 c1 e8 03          	shr    $0x3,%rax
   d:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1)
  12:	74 08                	je     0x1c
  14:	4c 89 ff             	mov    %r15,%rdi
  17:	e8 7b 75 c0 f7       	call   0xf7c07597
  1c:	4d 8b 3f             	mov    (%r15),%r15
  1f:	49 83 c7 18          	add    $0x18,%r15
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ff             	mov    %r15,%rdi
  34:	e8 5e 75 c0 f7       	call   0xf7c07597
  39:	4d 8b 3f             	mov    (%r15),%r15
  3c:	49                   	rex.WB
  3d:	8d                   	.byte 0x8d
  3e:	bf                   	.byte 0xbf
  3f:	98                   	cwtl

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/24 00:49 upstream c369299895a5 baf8bf12 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root general protection fault in rds_tcp_tc_info
* Struck through repros no longer work on HEAD.