From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=91.218.175.251 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793713076; b=cMLThWPxLWBZxMI3dvGL6rdsfnHy4lKeBd/o1PhrudDqwCuNP7c+GgZQAYWJGzW6ukVZ xOKGKaBsLqMUh0WuklUCYOcSKxrcNrIQyWKx7rnSpB85DP/DZhZzxglUrkfHQE5HT8I08 iPXj8A8RIdpdKEdy0araszesSL5wmeF/FyMstSPmJtOWnHqZs6tgKyPWqNsHBgf1alLv3 WgdsQP+HKfECowYGOnddQoZp3CNjdWw0o5IHu5LKHSZFvXEgd3TY9LOpj1jmrQRxhq9NS Ash4F68KxMlr44gf+OLEjD3+qoQb8dU1948Vi9t75+/ALNvtz44XAT9W9MkysMV5fNQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793713076; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:MIME-Version:Content-Transfer-Encoding; bh=hEMI+m3js1aFnCErRNCz/Cu9tKkq0BT32Y7SR0V+Acc=; b=mzHlpCV+zJRN93wxrH3wNZXzYH4nI4B4qmtIQJ4pF3VPImbWC/Y3w+VxfGvOTB5PHVOF WFnvKdzyymnPo+/7yJwHz6ktbLtAcc33hd+SKJJWxDlfFvlwZVc2lfpWpWTHRy/BsJaUr O6oeouNDw1nsFRjs2vBLh8NLUxLy90SYF8JVs94nm9XVr3XBD22Gw2X3w3iGMdMy8+Sz0 UIrA4AUfgYNHFKrtWhqrF3PglobTFdTZlP1MwD64C3M/IbAnVz2vrxN4r7V+ufddvZDNA QbU+Q6+fiCHWuePvsZIFpRiWDfud30jOXDmnUmyGg9WoN46GvC7nehWxsrGjaB0lbhg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=chenxiaosong.com; spf=pass smtp.mailfrom=chenxiaosong.com; dkim=pass header.d=chenxiaosong.com header.i=@chenxiaosong.com header.a=rsa-sha256 header.s=key1 header.b=Xu7eiIIg; arc=none smtp.remote-ip=91.218.175.251 Received: from mta0.migadu.com (out-251.mta0.migadu.com [91.218.175.251]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 60B63606A327 for ; Tue, 3 Nov 2026 13:37:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 60B63606A327 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=chenxiaosong.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chenxiaosong.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=chenxiaosong.com header.i=@chenxiaosong.com header.a=rsa-sha256 header.s=key1 header.b=Xu7eiIIg X-Envelope-To: linux-cifs@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=1gROWatEtva1QtksbHrY1qmsoeyLVAYi9rdrvKhCq6A=; c=simple/simple; d=chenxiaosong.com; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793713072; v=1; x=1794317872; b=Xu7eiIIgqrd4axQIsMNU3caB2TLn11BT7TeGZH38dOJDrFu8KrwB0VrSyWPTSuUzA/zcD2dA vg0itl4nCERnQL3V5CGFF2zTM0j+pAtRvaq+oNklw+4PyM23n+vMOHcubh2yiSjFo7kJmaeCKXY v18qK+nC9Rk4TrITnALnSn+Doi87yIKNScO+xhGL6jQtKwDjp3Z7tRPC3lXej+t3pRsKBZ3rvfo LQfWB9kgZpp4KN0Mt6cM4qs0XbzaLU11zvxp8eQAlgjOzLDfkI+eY3ICDcryiMXHjkVVAlEB4nh qk6lXF1jfXMKcecPovMpFeEspZqHU7HOn9xsv8H0lYgqQ== X-Envelope-To: linux-cifs@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id c2ab1624e596d386; Tue, 03 Nov 2026 13:37:51 +0000 X-Mizu-Trace-ID: c2ab1624e596d386 X-Migadu-Flow: FLOW_OUT From: ChenXiaoSong To: linkinjeon@kernel.org, tom@talpey.com, senozhatsky@chromium.org, chenxiaosong@chenxiaosong.com Cc: linux-cifs@vger.kernel.org, ChenXiaoSong Subject: [PATCH] smb/server: reject embedded NULs in EA names Date: Tue, 3 Nov 2026 13:37:36 +0000 Message-ID: <20261103133736.285341-1-chenxiaosong@chenxiaosong.com> X-Mailer: git-send-email 2.55.0 X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: ChenXiaoSong A client can send "DOSATTRIB\0suffix" as an EA name. The check sees a name longer than "DOSATTRIB" and lets it through. But the VFS stops at the first '\0', so the request writes to "user.DOSATTRIB", which should be blocked. Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Signed-off-by: ChenXiaoSong --- fs/smb/server/smb2pdu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index 9cb533a030f4..1be0de361c40 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -3455,7 +3455,8 @@ static int smb2_set_ea(struct smb2_ea_info *eabuf, unsigned int buf_len, if (!eabuf->EaNameLength) goto next; - if (eabuf->name[eabuf->EaNameLength]) { + if (eabuf->name[eabuf->EaNameLength] || + memchr(eabuf->name, '\0', eabuf->EaNameLength)) { rc = -EBADMSG; break; } -- 2.55.0