From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 92C6C5221FA; Wed, 30 Sep 2026 18:25:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790792753; cv=none; b=U1+/V+YLf87PFQnJ3U/czucGGh3xxcK37jvBuBOx14rKnM91Hfn5R89ks2rmcPxoVd/aHb/NPIfzJbuFDmDcLa9P4Hioy1/UHrTFTTWHvjn0C+vG0gJ7Kn6odg/3Z142lJO++YDowb1YT/bJ2uOioxqmSZmM3w8s+J+kajnuSHQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790792753; c=relaxed/simple; bh=SsatphcLP+FdfzNfek9P0e8mwcyv5VT5yNULt0RSiL8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bM+B+m9Vgi8lB6A2abZ93cN5G0coCBp49rIWxgz65YDT4gjVFQRgZ2g5Q/6DVuFcdw3nuN8+J5TTUObHfSIMKK6G9ncDKtg3NwrYtjc4GjkpK+gDK9MMp9G67pVCko8Yv8EK7a7ZoK5tMq+6u1cTwiMTaNR2VlNswONQG6AGL8o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=k9xH2NbD; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="k9xH2NbD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C05EE1F000FF; Wed, 30 Sep 2026 18:25:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790792752; bh=7Ki1MsdoUWSsxfTzq9r7D9m55tZSIGZeSwBqUnWNToc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=k9xH2NbDpPonJcXsGWoBxUPRpqKjXhrKolAqa3SY8BqRbIQZsQItKYRIrT10t8ipl V0bJ/MOdxML3ungu8HvnH6tA71ROirJf5JYhojQq/4gJYx0d5Z3joTcdDnCNXVwZ1o G5YbyfXzLSTWNcWIDmXl35sXj/jOBWnQnZpUBzZw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Xiang Mei (Microsoft)" , Jiayuan Chen , Kuniyuki Iwashima , Alexei Starovoitov , Sasha Levin Subject: [PATCH 6.18 014/395] bpf: Fix out-of-bounds read of sk_protocol in bpf_sock_destroy() Date: Wed, 30 Sep 2026 17:24:36 +0200 Message-ID: <20260930152340.925819414@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152340.591469096@linuxfoundation.org> References: <20260930152340.591469096@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiayuan Chen [ Upstream commit 01b245ba016d44861690594e10f67e026ce8552f ] sk_protocol lives in struct sock, not in struct sock_common. A timewait or request sock handed to bpf_sock_destroy() by the tcp iterator is neither, so reading sk->sk_protocol runs past the object: ================================================================== BUG: KASAN: slab-out-of-bounds in bpf_sock_destroy+0xc7/0xe0 Read of size 2 at addr ffff8881047d11b4 by task test_progs/428 Tainted: [W]=WARN Call Trace: dump_stack_lvl+0x91/0xf0 print_report+0xd1/0x630 kasan_report+0xf3/0x130 __asan_report_load2_noabort+0x14/0x30 bpf_sock_destroy+0xc7/0xe0 bpf_prog_c3dd61f9d9cd9f37_iter_tcp6_timewait+0x9f/0xb7 bpf_iter_run_prog+0x538/0xde0 bpf_iter_tcp_seq_show+0x26b/0x4b0 bpf_seq_read+0x424/0x1210 vfs_read+0x197/0xe40 ksys_read+0x119/0x240 __x64_sys_read+0x72/0xc0 x64_sys_call+0x647/0x27e0 do_syscall_64+0xe5/0x610 entry_SYSCALL_64_after_hwframe+0x76/0x7e Only check sk_protocol on full socks. tcp_abort() already knows how to deal with TIME_WAIT and NEW_SYN_RECV socks. Also fix the comment, it never matched the code. Fixes: 4ddbcb886268 ("bpf: Add bpf_sock_destroy kfunc") Reported-by: Xiang Mei (Microsoft) Closes: https://lore.kernel.org/bpf/20260702224519.800135-1-xmei5@asu.edu/ Signed-off-by: Jiayuan Chen Reviewed-by: Kuniyuki Iwashima Link: https://lore.kernel.org/r/20260910112634.152195-1-jiayuan.chen@linux.dev Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- net/core/filter.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index 0b849567afe9f..4f0a052d9aed1 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -12497,8 +12497,9 @@ __bpf_kfunc_start_defs(); * @sock: Pointer to socket to be destroyed * * Return: - * On error, may return EPROTONOSUPPORT, EINVAL. - * EPROTONOSUPPORT if protocol specific destroy handler is not supported. + * On error, may return EOPNOTSUPP, or whatever the protocol specific + * destroy handler returns. + * EOPNOTSUPP if protocol specific destroy handler is not supported. * 0 otherwise */ __bpf_kfunc int bpf_sock_destroy(struct sock_common *sock) @@ -12510,8 +12511,12 @@ __bpf_kfunc int bpf_sock_destroy(struct sock_common *sock) * Supporting protocols will need to acquire sock lock in the BPF context * prior to invoking this kfunc. */ - if (!sk->sk_prot->diag_destroy || (sk->sk_protocol != IPPROTO_TCP && - sk->sk_protocol != IPPROTO_UDP)) + if (!sk->sk_prot->diag_destroy) + return -EOPNOTSUPP; + + if (sk_fullsock(sk) && + sk->sk_protocol != IPPROTO_TCP && + sk->sk_protocol != IPPROTO_UDP) return -EOPNOTSUPP; return sk->sk_prot->diag_destroy(sk, ECONNABORTED); -- 2.53.0