From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f71.google.com (mail-oo1-f71.google.com [209.85.161.71]) (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 73F8E248891 for ; Sun, 4 Jan 2026 02:26:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.71 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767493567; cv=none; b=hi8nHD3gEqgj/2sYRlvJ/U5SVWqShqWniSwA95yKv7xMtZStFdEST+Xg//iuu6ivDW/pjYkL7/DDk9csdurfg81ZhNjKFdT1jFtedhLKRU+Jql4vt971zBbCfvluAy8PX9Ci24KMORndmk6u/uYlcyvsbYTp6pGXe8eiyO+GsDU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767493567; c=relaxed/simple; bh=YLzk93a8V+V77A9OIUtFUYN4A7n5WcfXNXCl2YMTYQY=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=J2He0WQdfnD+j6OM4QTJPdBJx7Zmq4d08T3v4HzQ+KcTuAVJncnMv4rRjwTYiCZERtAHHphEJ2JtUKnvoc3MEcLM0lxAtb9boa91a1GfCd6v78LcTasC86gwON5LnC66sTYuXYlgmx2ShR0u5YSPWSqSkE086DwubbPS0re0Ovk= 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=209.85.161.71 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-f71.google.com with SMTP id 006d021491bc7-65ec1bb9db9so23337002eaf.0 for ; Sat, 03 Jan 2026 18:26:04 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767493563; x=1768098363; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Nr8M4XPgpbKgMAObsjNBzUHT2tAwcesoaiXPklY9V+k=; b=S0nREseDDbdpOsWTjTxNAnQD1mu4iQwPA60kg0cErtQS1MQuJHPKqKosOB255lePg+ WrJfunYeoXUIpCvzSvvN5mzue7fm0oMig0k/Xy9lVIAyeb1I6GUpOvQYgaXaXfyJBryL Kv0WDfIonVPw/UK40fqPb91vLTogonrM0/s64OnPlkO2CfoUCPzhY3LWQ9tFL0dB1wbD Qhb6ZcfSpNiWVNQA3/Dxl+BApEqpSy3dAUmExQiUKYsbvNX0wqg7UgROZhKTixJm42rh +BlSKWDHaq3bKoHSiBtEzMx3JAOvKWgyGWK8z7rYVxJ4Hm0+YnZZWSJguO5U/p3xGjQl l8xA== X-Forwarded-Encrypted: i=1; AJvYcCXSn78hl1wcea/0327KcL9KAOLKyNhx//4YBuwaLfzm/+HTM2vZRXzxHcsyaiMJvrmMvGiqtmSpNbCKgc4=@vger.kernel.org X-Gm-Message-State: AOJu0Yyc0olm3220tK/2HnU1tAxOSKO6Di46B91/HeVxP2wdXA4WFYZs iqyMjjklpBCW4TM5Uu2yoWPA4uMjKqR/JCbWMeVfl6WhDr8AMnJUE8bdcw13U/VT6ms/kTSQ1HE 4jAFVbmpVLjZoc7onLpk3KpN43NrHkx8KEZd+fxS/fPoGsHzdBdeJA8r74lQ= X-Google-Smtp-Source: AGHT+IHJS5zLCJH/arWEdNDXk8YQKMioBWevdjl3R/Gp16r2z9x2VM0Q45QEZxXDjvdIyxxDR0LEZbkT3mi/Ozb+ZJYl+eKPSeig Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:827:b0:659:9a49:8f92 with SMTP id 006d021491bc7-65d0e9fe020mr19881906eaf.11.1767493563452; Sat, 03 Jan 2026 18:26:03 -0800 (PST) Date: Sat, 03 Jan 2026 18:26:03 -0800 In-Reply-To: <20260104020145.4942-1-kartikey406@gmail.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6959cfbb.050a0220.1c9965.0019.GAE@google.com> Subject: Re: [syzbot] [bpf?] KMSAN: uninit-value in bpf_prog_test_run_skb From: syzbot To: kartikey406@gmail.com, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: KMSAN: uninit-value in bpf_prog_test_run_skb ===================================================== BUG: KMSAN: uninit-value in bpf_prog_test_run_skb+0x3091/0x3200 net/bpf/test_run.c:-1 bpf_prog_test_run_skb+0x3091/0x3200 net/bpf/test_run.c:-1 bpf_prog_test_run+0x5bb/0x9f0 kernel/bpf/syscall.c:4703 __sys_bpf+0x873/0xeb0 kernel/bpf/syscall.c:6182 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline] __se_sys_bpf kernel/bpf/syscall.c:6272 [inline] __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6272 x64_sys_call+0x31c3/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was stored to memory at: pskb_expand_head+0x31a/0x15f0 net/core/skbuff.c:2290 __skb_cow include/linux/skbuff.h:3853 [inline] skb_cow_head include/linux/skbuff.h:3887 [inline] bpf_skb_net_grow net/core/filter.c:3511 [inline] ____bpf_skb_adjust_room net/core/filter.c:3754 [inline] bpf_skb_adjust_room+0x103c/0x3310 net/core/filter.c:3699 ___bpf_prog_run+0x1297/0xeba0 kernel/bpf/core.c:2037 __bpf_prog_run512+0xc5/0x100 kernel/bpf/core.c:2333 bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] bpf_test_run+0x496/0xe00 net/bpf/test_run.c:423 bpf_prog_test_run_skb+0x2377/0x3200 net/bpf/test_run.c:1158 bpf_prog_test_run+0x5bb/0x9f0 kernel/bpf/syscall.c:4703 __sys_bpf+0x873/0xeb0 kernel/bpf/syscall.c:6182 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline] __se_sys_bpf kernel/bpf/syscall.c:6272 [inline] __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6272 x64_sys_call+0x31c3/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was stored to memory at: skb_data_move+0x424/0x570 include/linux/skbuff.h:-1 skb_postpush_data_move include/linux/skbuff.h:4639 [inline] bpf_skb_generic_push net/core/filter.c:3267 [inline] bpf_skb_net_hdr_push net/core/filter.c:3305 [inline] bpf_skb_net_grow net/core/filter.c:3542 [inline] ____bpf_skb_adjust_room net/core/filter.c:3754 [inline] bpf_skb_adjust_room+0x116c/0x3310 net/core/filter.c:3699 ___bpf_prog_run+0x1297/0xeba0 kernel/bpf/core.c:2037 __bpf_prog_run512+0xc5/0x100 kernel/bpf/core.c:2333 bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] bpf_test_run+0x496/0xe00 net/bpf/test_run.c:423 bpf_prog_test_run_skb+0x2377/0x3200 net/bpf/test_run.c:1158 bpf_prog_test_run+0x5bb/0x9f0 kernel/bpf/syscall.c:4703 __sys_bpf+0x873/0xeb0 kernel/bpf/syscall.c:6182 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline] __se_sys_bpf kernel/bpf/syscall.c:6272 [inline] __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6272 x64_sys_call+0x31c3/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4960 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_node_noprof+0x9e7/0x17a0 mm/slub.c:5315 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:586 pskb_expand_head+0x201/0x15f0 net/core/skbuff.c:2282 __skb_cow include/linux/skbuff.h:3853 [inline] skb_cow_head include/linux/skbuff.h:3887 [inline] bpf_skb_net_grow net/core/filter.c:3511 [inline] ____bpf_skb_adjust_room net/core/filter.c:3754 [inline] bpf_skb_adjust_room+0x103c/0x3310 net/core/filter.c:3699 ___bpf_prog_run+0x1297/0xeba0 kernel/bpf/core.c:2037 __bpf_prog_run512+0xc5/0x100 kernel/bpf/core.c:2333 bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] bpf_test_run+0x496/0xe00 net/bpf/test_run.c:423 bpf_prog_test_run_skb+0x2377/0x3200 net/bpf/test_run.c:1158 bpf_prog_test_run+0x5bb/0x9f0 kernel/bpf/syscall.c:4703 __sys_bpf+0x873/0xeb0 kernel/bpf/syscall.c:6182 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline] __se_sys_bpf kernel/bpf/syscall.c:6272 [inline] __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6272 x64_sys_call+0x31c3/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 0 UID: 0 PID: 6585 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 ===================================================== Tested on: commit: aacb0a6d Merge tag 'pmdomain-v6.19-rc3' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16e50074580000 kernel config: https://syzkaller.appspot.com/x/.config?x=b3903bdf68407a14 dashboard link: https://syzkaller.appspot.com/bug?extid=619b9ef527f510a57cfc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 patch: https://syzkaller.appspot.com/x/patch.diff?x=1231369a580000