From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f77.google.com (mail-oo1-f77.google.com [209.85.161.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 04E5B48166A for ; Wed, 21 Jan 2026 10:03:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.77 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768989809; cv=none; b=WWnefUU7u2HsV4QmKADlJbNxHeoWJPMyrii3jFexvRqQz8r3Rw/0prgsTHUsVb7Cs82V9lbmvqFv+m/0vnoVwjYo+um8IvxY84ARK19RujUX57kakuxRgGjvwSCzuVNGIQjP+VQMUBRxeZPLdTYjyb8GqRNwwVAEL6elt//H1LY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768989809; c=relaxed/simple; bh=a8lRbOZtGBevnU6kM7N4iWrnq0zLG+iolcddCE+0i+w=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=NFnmnZVRG/w82iGZBULLF6M5BRNeniP0VjliAFZefiSiWDL6wnnBj58Ot8vfNTIIniV4r/WIu5tFxvRrw+75fySBVd0OtxcLTb3XwOJ2rxfzYxWJCrzs+/cDU+DNKvXHpHLSvm5jn67t2cStBaR98mE02KUILC9vJvz8QzJYK3k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.161.77 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo1-f77.google.com with SMTP id 006d021491bc7-6611cbc47a2so6630344eaf.0 for ; Wed, 21 Jan 2026 02:03:26 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768989806; x=1769594606; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=zdyniw39ghninlZtPjfoFJ6njLUlXXDlw/5pb7W19XE=; b=ioHjxYKO12/SFADdMp0+WGwAkBF2nRYtCYvZF3B3vkgBAuh68B6gcjCZriM39Qi/RB 3oCSAynf9sP3L31Wqkz5LMivJyCalL3KXMz3sLOVHvPIfcU7liTLLmXRgkR4lMCmBrqQ SWF0O964q0V69sPLfi/RCa/UiWBf/m1x75b8SPOOIGqr7vIcISKfxTlwwbujML4B8jw2 1G5r+vfnt/ITJOO1xW7mPnsaHzxMlx8GyRJWNP+ZwKO0xm9nYXcn0pJRa12xjtxTFZfJ xk01ZcSb633sxF8VVkeIlqFc1Gr3FaPAY9SbAunzODe6fiWTi7CfaXIsOjVLrHG0BA8E 4Q8g== X-Forwarded-Encrypted: i=1; AJvYcCX+vC3X1tOj8VOwmtLiShKUgsqQonlHJgeRq9aFdZBC7XEP0KSoaNJBiw1udXAZeZByU2IHYU0=@vger.kernel.org X-Gm-Message-State: AOJu0YyleFm5Yy+8XerpLKAnsxBxWnmQVbJOIcA1mRz8sb4B9gCpcQuv YoCiL6VQUazfzChaL4HWqBCp+GVXciOnBRJKfn7Ebhuh6YnpNRm75yYoLSznyT7SjZuAUJG5nbE OaSE6EVIP0eOh1gld+DJQjglGFdOki2m4slVutEtYGvX0wmMfNwrFqsq37dE= Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:2229:b0:65d:bb62:805 with SMTP id 006d021491bc7-66118924814mr7532463eaf.41.1768989805924; Wed, 21 Jan 2026 02:03:25 -0800 (PST) Date: Wed, 21 Jan 2026 02:03:25 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6970a46d.a00a0220.3ad28e.5cf0.GAE@google.com> Subject: [syzbot] [mptcp?] KASAN: stack-out-of-bounds Read in mptcp_pm_nl_get_local_id From: syzbot To: davem@davemloft.net, edumazet@google.com, geliang@kernel.org, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, martineau@kernel.org, matttbe@kernel.org, mptcp@lists.linux.dev, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 22cc16c04b78 riscv, bpf: Fix incorrect usage of BPF_TRAMP_.. git tree: bpf console output: https://syzkaller.appspot.com/x/log.txt?x=10be528a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=a94030c847137a18 dashboard link: https://syzkaller.appspot.com/bug?extid=5498a510ff9de39d37da compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/43a53493cb5f/disk-22cc16c0.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/9726fb9e1980/vmlinux-22cc16c0.xz kernel image: https://storage.googleapis.com/syzbot-assets/efd2bc050ab6/bzImage-22cc16c0.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+5498a510ff9de39d37da@syzkaller.appspotmail.com ================================================================== BUG: KASAN: stack-out-of-bounds in __lookup_addr net/mptcp/pm_kernel.c:283 [inline] BUG: KASAN: stack-out-of-bounds in mptcp_pm_nl_get_local_id+0x183/0x330 net/mptcp/pm_kernel.c:905 Read of size 2 at addr ffffc90003237354 by task syz.8.3557/19241 CPU: 0 UID: 0 PID: 19241 Comm: syz.8.3557 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __lookup_addr net/mptcp/pm_kernel.c:283 [inline] mptcp_pm_nl_get_local_id+0x183/0x330 net/mptcp/pm_kernel.c:905 mptcp_pm_get_local_id+0x4ab/0x5b0 net/mptcp/pm.c:925 subflow_chk_local_id+0x101/0x220 net/mptcp/subflow.c:641 subflow_v6_rebuild_header+0x16/0x50 net/mptcp/subflow.c:664 tcp_connect+0x205/0x4f50 net/ipv4/tcp_output.c:4312 tcp_v6_connect+0x1222/0x18a0 net/ipv6/tcp_ipv6.c:336 mptcp_connect+0x56b/0x830 net/mptcp/protocol.c:3977 __inet_stream_connect+0x2ae/0xe70 net/ipv4/af_inet.c:679 tcp_sendmsg_fastopen+0x3a7/0x5e0 net/ipv4/tcp.c:1064 mptcp_sendmsg_fastopen+0x17d/0x580 net/mptcp/protocol.c:1780 mptcp_sendmsg+0x179f/0x19b0 net/mptcp/protocol.c:1880 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0xe5/0x270 net/socket.c:742 ____sys_sendmsg+0x505/0x820 net/socket.c:2592 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2681 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5218b8f749 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:00007f5219a1c038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f5218de6090 RCX: 00007f5218b8f749 RDX: e07e872420dfef8a RSI: 0000200000000780 RDI: 0000000000000003 RBP: 00007f5218c13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5218de6128 R14: 00007f5218de6090 R15: 00007ffd434acc78 The buggy address belongs to a 8-page vmalloc region starting at 0xffffc90003230000 allocated at copy_process+0x4ea/0x3950 kernel/fork.c:2052 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x7f2bc8e1d pfn:0x6bcdf memcg:ffff88801df3ec02 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 00000007f2bc8e1d 0000000000000000 00000001ffffffff ffff88801df3ec02 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x29c2(GFP_NOWAIT|__GFP_HIGHMEM|__GFP_IO|__GFP_FS|__GFP_ZERO), pid 19239, tgid 19239 (syz.8.3557), ts 697879712329, free_ts 697878067160 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline] alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2577 vm_area_alloc_pages mm/vmalloc.c:3649 [inline] __vmalloc_area_node mm/vmalloc.c:3863 [inline] __vmalloc_node_range_noprof+0x795/0x16a0 mm/vmalloc.c:4051 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:4111 alloc_thread_stack_node kernel/fork.c:354 [inline] dup_task_struct+0x228/0x9a0 kernel/fork.c:923 copy_process+0x4ea/0x3950 kernel/fork.c:2052 kernel_clone+0x21e/0x820 kernel/fork.c:2651 __do_sys_clone3 kernel/fork.c:2953 [inline] __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2932 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 19240 tgid 19239 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943 bpf_check+0x164a7/0x1c300 kernel/bpf/verifier.c:25396 bpf_prog_load+0x13ba/0x1a10 kernel/bpf/syscall.c:3088 __sys_bpf+0x507/0x860 kernel/bpf/syscall.c:6164 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline] __se_sys_bpf kernel/bpf/syscall.c:6272 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6272 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffffc90003237200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90003237280: 00 00 00 00 f1 f1 f1 f1 00 01 f2 f2 00 01 f2 f2 >ffffc90003237300: 00 f2 f2 f2 00 f2 f2 f2 00 00 f3 f3 00 00 00 00 ^ ffffc90003237380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90003237400: f1 f1 f1 f1 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- This report is generated by a bot. 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