[PATCH] cifs: Fix check for regular file in couldbe_mf_symlink()

[Sachin Prabhu]

MF Symlinks are regular files containing content in a specified format.

The function couldbe_mf_symlink() checks the mode for a set S_IFREG bit
as a test to confirm that it is a regular file. This bit is also set for
other filetypes and simply checking for this bit being set may return
false positives.

We ensure that we are actually checking for a regular file by using the
S_ISREG macro to test instead.

Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+***@public.gmane.org>
Reported-by: Neil Brown <neilb-***@public.gmane.org>
Reported-by: Dan Carpenter <dan.carpenter-QHcLZuEGTsvQT0dZR+***@public.gmane.org>
---
fs/cifs/link.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index 52f41f9..264ece7 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -185,7 +185,7 @@ format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
bool
couldbe_mf_symlink(const struct cifs_fattr *fattr)
{
- if (!(fattr->cf_mode & S_IFREG))
+ if (!S_ISREG(fattr->cf_mode))
/* it's not a symlink */
return false;

[Jeff Layton]

On Fri, 31 Jan 2014 14:27:16 +0000

Post by Sachin Prabhu
MF Symlinks are regular files containing content in a specified format.
The function couldbe_mf_symlink() checks the mode for a set S_IFREG bit
as a test to confirm that it is a regular file. This bit is also set for
other filetypes and simply checking for this bit being set may return
false positives.
We ensure that we are actually checking for a regular file by using the
S_ISREG macro to test instead.
---
fs/cifs/link.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index 52f41f9..264ece7 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -185,7 +185,7 @@ format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
bool
couldbe_mf_symlink(const struct cifs_fattr *fattr)
{
- if (!(fattr->cf_mode & S_IFREG))
+ if (!S_ISREG(fattr->cf_mode))
/* it's not a symlink */
return false;

Looks correct.

Reviewed-by: Jeff Layton <jlayton-H+wXaHxf7aLQT0dZR+***@public.gmane.org>

[Steve French]

merged into cifs-2.6.git for-next

Post by Jeff Layton
On Fri, 31 Jan 2014 14:27:16 +0000

Post by Sachin Prabhu
MF Symlinks are regular files containing content in a specified format.
The function couldbe_mf_symlink() checks the mode for a set S_IFREG bit
as a test to confirm that it is a regular file. This bit is also set for
other filetypes and simply checking for this bit being set may return
false positives.
We ensure that we are actually checking for a regular file by using the
S_ISREG macro to test instead.
---
fs/cifs/link.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index 52f41f9..264ece7 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -185,7 +185,7 @@ format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
bool
couldbe_mf_symlink(const struct cifs_fattr *fattr)
{
- if (!(fattr->cf_mode & S_IFREG))
+ if (!S_ISREG(fattr->cf_mode))
/* it's not a symlink */
return false;

Looks correct.