From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6FA862F39CE for ; Mon, 30 Mar 2026 19:10:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774897840; cv=none; b=AYZQzqXmf7AzPkr+cfivC8WhwQRC0Fkze7L4OQA89QiRLgfhnGZCCdHPWcbvrZanh8wfODuC2zcgOd0gYywXG8d1fA1LMuo+3E4H90QK+hSBWDtCQfC9SLcNOyU6PZBkkvspdLc+XvW+C8HCMQNH1Paiha3qqVTh/y0P9rCstFY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774897840; c=relaxed/simple; bh=C0sRzY2agXv1kvcy9rFOsc1n3rrSieU+SdmB4lXhl3A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MAK3/1qKyZXvWLhHctDJjqQzKsmfm5TeG7kEv8JrlTJgx0f+bMK5NqfE4bkoffA+ms0th5rqxEFThd0euS90MTDyu8PPS/lLjbZ+D9Pc2S75kNw/9vRizsIs4r6KLCemn4G3maPARkososd0IgAZAGOI+P51vHAev71o8hCjwJw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fkXqroXx; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fkXqroXx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63941C4CEF7; Mon, 30 Mar 2026 19:10:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774897840; bh=C0sRzY2agXv1kvcy9rFOsc1n3rrSieU+SdmB4lXhl3A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fkXqroXxjHWMtenb4JbK97z5pNxy4wZpjS3IkUR2e/6+oe4kHZmXd2wrQr2o7YDVW X1QKjybMfqRnuh2zbBD+tKJ8MXP92KWputDNXwBv+JMLUfqg0qH2AhozOPVEIHKfDb vMta/QQiAKh3S8drfL4UD9fkrqyhHr6QxMUop5+VVbnkJFunMjM2dMfWnD5XMqjPgV k1ZLjwXY5Uq5jh+GKIzTWrYOGhn9JvJRbcrnrY9xubN1/9xLe8V5CDPmnOr8FPYrmu WXEEqvvNd05gu3RXz5yykZXuKQGzyq6jsFIjPsemjqfLzRSdBizjB+FaVE2kPsPCZt gn7Xm4M4gVCGQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Namjae Jeon , Asim Viladi Oglu Manizada , Steve French , Sasha Levin Subject: [PATCH 5.15.y] ksmbd: fix potencial OOB in get_file_all_info() for compound requests Date: Mon, 30 Mar 2026 15:10:37 -0400 Message-ID: <20260330191037.1035485-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026032931-tubby-automatic-2197@gregkh> References: <2026032931-tubby-automatic-2197@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Namjae Jeon [ Upstream commit beef2634f81f1c086208191f7228bce1d366493d ] When a compound request consists of QUERY_DIRECTORY + QUERY_INFO (FILE_ALL_INFORMATION) and the first command consumes nearly the entire max_trans_size, get_file_all_info() would blindly call smbConvertToUTF16() with PATH_MAX, causing out-of-bounds write beyond the response buffer. In get_file_all_info(), there was a missing validation check for the client-provided OutputBufferLength before copying the filename into FileName field of the smb2_file_all_info structure. If the filename length exceeds the available buffer space, it could lead to potential buffer overflows or memory corruption during smbConvertToUTF16 conversion. This calculating the actual free buffer size using smb2_calc_max_out_buf_len() and returning -EINVAL if the buffer is insufficient and updating smbConvertToUTF16 to use the actual filename length (clamped by PATH_MAX) to ensure a safe copy operation. Cc: stable@vger.kernel.org Fixes: e2b76ab8b5c9 ("ksmbd: add support for read compound") Reported-by: Asim Viladi Oglu Manizada Signed-off-by: Namjae Jeon Signed-off-by: Steve French [ adapted variable declarations ] Signed-off-by: Sasha Levin --- fs/ksmbd/smb2pdu.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index b5ff4c855f9cb..07144891d9784 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -4564,6 +4564,8 @@ static int get_file_all_info(struct ksmbd_work *work, int conv_len; char *filename; u64 time; + int buf_free_len, filename_len; + struct smb2_query_info_req *req = ksmbd_req_buf_next(work); if (!(fp->daccess & FILE_READ_ATTRIBUTES_LE)) { ksmbd_debug(SMB, "no right to read the attributes : 0x%x\n", @@ -4575,6 +4577,16 @@ static int get_file_all_info(struct ksmbd_work *work, if (IS_ERR(filename)) return PTR_ERR(filename); + filename_len = strlen(filename); + buf_free_len = smb2_calc_max_out_buf_len(work, + offsetof(struct smb2_query_info_rsp, Buffer) + + offsetof(struct smb2_file_all_info, FileName), + le32_to_cpu(req->OutputBufferLength)); + if (buf_free_len < (filename_len + 1) * 2) { + kfree(filename); + return -EINVAL; + } + inode = file_inode(fp->filp); generic_fillattr(file_mnt_user_ns(fp->filp), inode, &stat); @@ -4606,7 +4618,8 @@ static int get_file_all_info(struct ksmbd_work *work, file_info->Mode = fp->coption; file_info->AlignmentRequirement = 0; conv_len = smbConvertToUTF16((__le16 *)file_info->FileName, filename, - PATH_MAX, conn->local_nls, 0); + min(filename_len, PATH_MAX), + conn->local_nls, 0); conv_len *= 2; file_info->FileNameLength = cpu_to_le32(conv_len); rsp->OutputBufferLength = -- 2.53.0