All of lore.kernel.org
 help / color / mirror / Atom feed
From: Steve French <smfrench@gmail.com>
To: CIFS <linux-cifs@vger.kernel.org>
Subject: [PATCH] CIFS: Clarify SMB1 code for UnixCreateSymLink
Date: Thu, 1 Jul 2021 20:48:49 -0500	[thread overview]
Message-ID: <CAH2r5muwZikVYiE7J+mwBxFLRe4yP4YsA-=vBJQ56KGfRabNKw@mail.gmail.com> (raw)

[-- Attachment #1: Type: text/plain, Size: 1175 bytes --]

Coverity also complains about the way we calculate the offset
(starting from the address of a 4 byte array within the
header structure rather than from the beginning of the struct
plus 4 bytes) for creating SMB1 symlinks when using the Unix
extensions.  This doesn't change the address but
makes it slightly clearer.

Addresses-Coverity: 711530 ("Out of bounds read")
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
---
 fs/cifs/cifssmb.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index ea12fa6eacb6..a14d3f533301 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -2925,7 +2925,8 @@ CIFSUnixCreateSymLink(const unsigned int xid,
struct cifs_tcon *tcon,
  InformationLevel) - 4;
  offset = param_offset + params;

- data_offset = (char *) (&pSMB->hdr.Protocol) + offset;
+ /* SMB offsets are from the beginning of SMB which is 4 bytes in,
after RFC1001 field */
+ data_offset = (char *)pSMB + offset + 4;
  if (pSMB->hdr.Flags2 & SMBFLG2_UNICODE) {
  name_len_target =
      cifsConvertToUTF16((__le16 *) data_offset, toName,

-- 
Thanks,

Steve

[-- Attachment #2: 0001-CIFS-Clarify-SMB1-code-for-UnixCreateSymLink.patch --]
[-- Type: text/x-patch, Size: 1389 bytes --]

From e7198dbf8b62296319690da591c396cf05d91c65 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@microsoft.com>
Date: Thu, 1 Jul 2021 20:44:27 -0500
Subject: [PATCH] CIFS: Clarify SMB1 code for UnixCreateSymLink

Coverity also complains about the way we calculate the offset
(starting from the address of a 4 byte array within the
header structure rather than from the beginning of the struct
plus 4 bytes) for creating SMB1 symlinks when using the Unix
extensions.  This doesn't change the address but
makes it slightly clearer.

Addresses-Coverity: 711529 ("Out of bounds read")
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
---
 fs/cifs/cifssmb.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index ea12fa6eacb6..a14d3f533301 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -2925,7 +2925,8 @@ CIFSUnixCreateSymLink(const unsigned int xid, struct cifs_tcon *tcon,
 				InformationLevel) - 4;
 	offset = param_offset + params;
 
-	data_offset = (char *) (&pSMB->hdr.Protocol) + offset;
+	/* SMB offsets are from the beginning of SMB which is 4 bytes in, after RFC1001 field */
+	data_offset = (char *)pSMB + offset + 4;
 	if (pSMB->hdr.Flags2 & SMBFLG2_UNICODE) {
 		name_len_target =
 		    cifsConvertToUTF16((__le16 *) data_offset, toName,
-- 
2.30.2


                 reply	other threads:[~2021-07-02  1:49 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CAH2r5muwZikVYiE7J+mwBxFLRe4yP4YsA-=vBJQ56KGfRabNKw@mail.gmail.com' \
    --to=smfrench@gmail.com \
    --cc=linux-cifs@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.