From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794590859; b=EwQ5D6tJiaLEOHEz80IddqVIyCgnSKJ4JFnPp0mN3Ssqp1OMoFbZq7LFC3lrnZzQh/jD Rd70AV1ug4n0x25IYLD5fCVMg11ywU2rAb4TQKucF00VPIfC+ogxGLCnp1fpvOG94noha dxjBScbcsHN2fKDazC6FkaexsM4fqkjDHizO8ZCqFFCGF9LCzlnX+FTwTrnIDiy7nYlaF mB3LkU5wX0fKCnIlqqWLYtQZudUTz5WySoWDFDkxeu0kSps2rTiFcTzf5iVXsOv7Y+yyv O+PRx8SNo555/F/M8BnosIRgVLw+CvkWh2ewVgrlqtXZRUHzFpBro/Wr9uNGzAtzMzw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794590859; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=ly9ccexSAr2Df40NZbBKNOKpxhhZ5d1FHZTFvHhHV1o=; b=JcKorNSqwfxufMzF2X4jgAAQeWfLhKC5FpasQSXSAOvgzB52L8BTamu/2MQU9lp5Ua1s nmjbbIJ97KovHE8tEvZIHr/bk46pOa8oORd7PMkP4ORd6mCgqY/2EQK3qj6viQoVH6e8n aTeiQO837+l8L+Q+IIwhCAyNLVqLaq52M1vZYy8aQIsgK2EmmDDL/PKa90vquxXjechDl dCwACBKeuWWOQkZXreur0Os+IvLk3oh9PALtisxQYqJP6lo364QMxVkFR1OQUDlTGzGZ9 NIMswMf7A12S6VnQFJo6q/SSi6yLlMvKc4c1ZKTLPLzJATHmgSeqN1rQIWMHKX1GCfQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b="G/cep7MS"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A80D1606D4A0; Fri, 13 Nov 2026 17:27:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=G/cep7MS Received: by smtp.kernel.org (Postfix) with ESMTPSA id 053EF1F000C4; Fri, 13 Nov 2026 17:27:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794590859; bh=ly9ccexSAr2Df40NZbBKNOKpxhhZ5d1FHZTFvHhHV1o=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=G/cep7MSMHFJj0+HY9UTuiAi7T20i4fU9UbClCCd0NhyvVek3OWWv9wBMkTbwIZx8 VgYB8xCulwHjiJU26vuiHP4uFlj/v02Ci6RerwzQ7la0br7bd9+3puI+z9roWtwe7/ yJzybygmwDrcUjCMu8P11UlwXjRRObWIdD+vhLiY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ratnaker Gautam , Paulo Alcantara , Sasha Levin Subject: [PATCH 6.12 017/670] smb: client: validate SMB1 EA list bounds before parsing Date: Fri, 13 Nov 2026 10:43:01 -0500 Message-ID: <20261113153811.769483066@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153811.177190860@linuxfoundation.org> References: <20261113153811.177190860@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ratnaker Gautam [ Upstream commit ddc7a7e1eeb116ccaf010a6f1fb6ab927f3f888d ] CIFSSMBQAllEAs() checks the server-provided EA list length by adding it to the response pointer. On 32-bit systems, a positive length can wrap the pointer and pass the comparison. The parser then walks outside the received response while reading the next FEA header. A response with a list length of 0x40000000 reproduces this as a native i386 page fault and kernel panic from listxattr() against an SMB1 server. Check that the EA list starts within the SMB byte area before reading its header. Keep its length unsigned and compare it with the bytes left in the response without pointer addition. SMB1 is not negotiated by default and requires an explicit vers=1.0 mount. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Ratnaker Gautam Signed-off-by: Paulo Alcantara [ sashal: Replaced unavailable smb_EIO2() tracing calls with direct -EIO assignments. ] Signed-off-by: Sasha Levin --- fs/smb/client/cifssmb.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c index 45c6eb11356ba..1c2b73bdef6cb 100644 --- a/fs/smb/client/cifssmb.c +++ b/fs/smb/client/cifssmb.c @@ -5763,9 +5763,11 @@ CIFSSMBQAllEAs(const unsigned int xid, struct cifs_tcon *tcon, int rc = 0; int bytes_returned; int list_len; + u32 ea_list_len; struct fealist *ea_response_data; struct fea *temp_fea; char *temp_ptr; + char *byte_area; char *end_of_smb; __u16 params, byte_count, data_offset; unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0; @@ -5842,9 +5844,18 @@ CIFSSMBQAllEAs(const unsigned int xid, struct cifs_tcon *tcon, ea_response_data = (struct fealist *) (((char *) &pSMBr->hdr.Protocol) + data_offset); - list_len = le32_to_cpu(ea_response_data->list_len); - cifs_dbg(FYI, "ea length %d\n", list_len); - if (list_len <= 8) { + byte_area = pByteArea(&pSMBr->hdr); + end_of_smb = byte_area + get_bcc(&pSMBr->hdr); + if ((char *)ea_response_data < byte_area || + (char *)ea_response_data > + end_of_smb - sizeof(ea_response_data->list_len)) { + rc = -EIO; + goto QAllEAsOut; + } + + ea_list_len = le32_to_cpu(ea_response_data->list_len); + cifs_dbg(FYI, "%s: ea length: %u\n", __func__, ea_list_len); + if (ea_list_len <= 8) { cifs_dbg(FYI, "empty EA list returned from server\n"); /* didn't find the named attribute */ if (ea_name) @@ -5853,12 +5864,12 @@ CIFSSMBQAllEAs(const unsigned int xid, struct cifs_tcon *tcon, } /* make sure list_len doesn't go past end of SMB */ - end_of_smb = (char *)pByteArea(&pSMBr->hdr) + get_bcc(&pSMBr->hdr); - if ((char *)ea_response_data + list_len > end_of_smb) { + if (ea_list_len > end_of_smb - (char *)ea_response_data) { cifs_dbg(FYI, "EA list appears to go beyond SMB\n"); rc = -EIO; goto QAllEAsOut; } + list_len = ea_list_len; /* account for ea list len */ list_len -= 4; -- 2.53.0