[syzbot] [net?] general protection fault in add_grec (2)
From: syzbot <hidden>
Date: 2025-06-10 08:01:38
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Hello, syzbot found the following issue on: HEAD commit: 64980441d269 Merge tag 'bpf-fixes' of git://git.kernel.org.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=169cf40c580000 kernel config: https://syzkaller.appspot.com/x/.config?x=26abb92f9ef9d1d0 dashboard link: https://syzkaller.appspot.com/bug?extid=2d29aae505225ce697ee compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/6f87fde80a0d/disk-64980441.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0f721fc8ffe8/vmlinux-64980441.xz kernel image: https://storage.googleapis.com/syzbot-assets/50b2b318eca4/bzImage-64980441.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2d29aae505225ce697ee@syzkaller.appspotmail.com Oops: general protection fault, probably for non-canonical address 0xdffffc001fffe000: 0000 [#1] SMP KASAN PTI KASAN: probably user-memory-access in range [0x00000000ffff0000-0x00000000ffff0007] CPU: 1 UID: 0 PID: 5815 Comm: kworker/1:3 Not tainted 6.15.0-syzkaller-12058-g64980441d269 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: mld mld_ifc_work RIP: 0010:add_grec+0x764/0x1670 net/ipv6/mcast.c:1967 Code: 40 01 41 89 c7 31 ff 89 c6 e8 08 b3 a2 f7 45 85 ff 0f 84 b0 00 00 00 e8 ba ae a2 f7 eb 05 e8 b3 ae a2 f7 49 89 ee 49 c1 ee 03 <43> 80 3c 26 00 74 08 48 89 ef e8 9d f5 03 f8 48 8b 45 00 48 89 84 RSP: 0018:ffffc9000425f8f8 EFLAGS: 00010206 RAX: ffffffff8a1d9c16 RBX: 0000000000000000 RCX: ffff888027a33c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 00000000ffff0000 R08: ffff888027a33c00 R09: 0000000000000002 R10: 0000000000000004 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000005 R14: 000000001fffe000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125d89000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f84328dc0d1 CR3: 000000006bf3c000 CR4: 00000000003526f0 DR0: 0000000000000007 DR1: 000000000000000b DR2: 0000000000000002 DR3: 0000000000000009 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> mld_send_cr net/ipv6/mcast.c:2155 [inline] mld_ifc_work+0x671/0xde0 net/ipv6/mcast.c:2702 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:add_grec+0x764/0x1670 net/ipv6/mcast.c:1967 Code: 40 01 41 89 c7 31 ff 89 c6 e8 08 b3 a2 f7 45 85 ff 0f 84 b0 00 00 00 e8 ba ae a2 f7 eb 05 e8 b3 ae a2 f7 49 89 ee 49 c1 ee 03 <43> 80 3c 26 00 74 08 48 89 ef e8 9d f5 03 f8 48 8b 45 00 48 89 84 RSP: 0018:ffffc9000425f8f8 EFLAGS: 00010206 RAX: ffffffff8a1d9c16 RBX: 0000000000000000 RCX: ffff888027a33c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 00000000ffff0000 R08: ffff888027a33c00 R09: 0000000000000002 R10: 0000000000000004 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000005 R14: 000000001fffe000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125d89000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f84328dc0d1 CR3: 00000000736c2000 CR4: 00000000003526f0 DR0: 0000000000000007 DR1: 000000000000000b DR2: 0000000000000002 DR3: 0000000000000009 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 41 89 c7 mov %eax,%r15d 3: 31 ff xor %edi,%edi 5: 89 c6 mov %eax,%esi 7: e8 08 b3 a2 f7 call 0xf7a2b314 c: 45 85 ff test %r15d,%r15d f: 0f 84 b0 00 00 00 je 0xc5 15: e8 ba ae a2 f7 call 0xf7a2aed4 1a: eb 05 jmp 0x21 1c: e8 b3 ae a2 f7 call 0xf7a2aed4 21: 49 89 ee mov %rbp,%r14 24: 49 c1 ee 03 shr $0x3,%r14 * 28: 43 80 3c 26 00 cmpb $0x0,(%r14,%r12,1) <-- trapping instruction 2d: 74 08 je 0x37 2f: 48 89 ef mov %rbp,%rdi 32: e8 9d f5 03 f8 call 0xf803f5d4 37: 48 8b 45 00 mov 0x0(%rbp),%rax 3b: 48 rex.W 3c: 89 .byte 0x89 3d: 84 .byte 0x84 --- This report is generated by a bot. 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