Re: [PATCH] cifs: smb2ops: Fix NULL check in smb2_query_symlink

[Pavel Shilovsky]

2018-04-13 8:13 GMT-07:00 Gustavo A. R. Silva :
> The current code null checks variable err_buf, which is always null
> when it is checked, hence utf16_path is free'd and the function
> returns -ENOENT everytime it is called, making it impossible for the
> execution path to reach the following code:
>
> err_buf = err_iov.iov_base;
>
> Fix this by null checking err_iov.iov_base instead of err_buf. Also,
> notice that err_buf no longer needs to be initialized to NULL.
>
> Addresses-Coverity-ID: 1467876 ("Logically dead code")
> Fixes: 2d636199e400 ("cifs: Change SMB2_open to return an iov for the error 
> parameter")
> Signed-off-by: Gustavo A. R. Silva 
> ---
>  fs/cifs/smb2ops.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> index b4ae932..38ebf3f 100644
> --- a/fs/cifs/smb2ops.c
> +++ b/fs/cifs/smb2ops.c
> @@ -1452,7 +1452,7 @@ smb2_query_symlink(const unsigned int xid, struct 
> cifs_tcon *tcon,
> struct cifs_open_parms oparms;
> struct cifs_fid fid;
> struct kvec err_iov = {NULL, 0};
> -   struct smb2_err_rsp *err_buf = NULL;
> +   struct smb2_err_rsp *err_buf;
> struct smb2_symlink_err_rsp *symlink;
> unsigned int sub_len;
> unsigned int sub_offset;
> @@ -1476,7 +1476,7 @@ smb2_query_symlink(const unsigned int xid, struct 
> cifs_tcon *tcon,
>
> rc = SMB2_open(xid, , utf16_path, , NULL, _iov);
>
> -   if (!rc || !err_buf) {
> +   if (!rc || !err_iov.iov_base) {
> kfree(utf16_path);
> return -ENOENT;
> }
> --
> 2.7.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majord...@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Thanks!

Reviewed-by: Pavel Shilovsky 

--
Best regards,
Pavel Shilovsky

Re: [PATCH] cifs: smb2ops: Fix NULL check in smb2_query_symlink

[Pavel Shilovsky]

2018-04-13 8:13 GMT-07:00 Gustavo A. R. Silva :
> The current code null checks variable err_buf, which is always null
> when it is checked, hence utf16_path is free'd and the function
> returns -ENOENT everytime it is called, making it impossible for the
> execution path to reach the following code:
>
> err_buf = err_iov.iov_base;
>
> Fix this by null checking err_iov.iov_base instead of err_buf. Also,
> notice that err_buf no longer needs to be initialized to NULL.
>
> Addresses-Coverity-ID: 1467876 ("Logically dead code")
> Fixes: 2d636199e400 ("cifs: Change SMB2_open to return an iov for the error 
> parameter")
> Signed-off-by: Gustavo A. R. Silva 
> ---
>  fs/cifs/smb2ops.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> index b4ae932..38ebf3f 100644
> --- a/fs/cifs/smb2ops.c
> +++ b/fs/cifs/smb2ops.c
> @@ -1452,7 +1452,7 @@ smb2_query_symlink(const unsigned int xid, struct 
> cifs_tcon *tcon,
> struct cifs_open_parms oparms;
> struct cifs_fid fid;
> struct kvec err_iov = {NULL, 0};
> -   struct smb2_err_rsp *err_buf = NULL;
> +   struct smb2_err_rsp *err_buf;
> struct smb2_symlink_err_rsp *symlink;
> unsigned int sub_len;
> unsigned int sub_offset;
> @@ -1476,7 +1476,7 @@ smb2_query_symlink(const unsigned int xid, struct 
> cifs_tcon *tcon,
>
> rc = SMB2_open(xid, , utf16_path, , NULL, _iov);
>
> -   if (!rc || !err_buf) {
> +   if (!rc || !err_iov.iov_base) {
> kfree(utf16_path);
> return -ENOENT;
> }
> --
> 2.7.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majord...@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Thanks!

Reviewed-by: Pavel Shilovsky 

--
Best regards,
Pavel Shilovsky

[PATCH] cifs: smb2ops: Fix NULL check in smb2_query_symlink

[Gustavo A. R. Silva]

The current code null checks variable err_buf, which is always null
when it is checked, hence utf16_path is free'd and the function
returns -ENOENT everytime it is called, making it impossible for the
execution path to reach the following code:

err_buf = err_iov.iov_base;

Fix this by null checking err_iov.iov_base instead of err_buf. Also,
notice that err_buf no longer needs to be initialized to NULL.

Addresses-Coverity-ID: 1467876 ("Logically dead code")
Fixes: 2d636199e400 ("cifs: Change SMB2_open to return an iov for the error 
parameter")
Signed-off-by: Gustavo A. R. Silva 
---
 fs/cifs/smb2ops.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index b4ae932..38ebf3f 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1452,7 +1452,7 @@ smb2_query_symlink(const unsigned int xid, struct 
cifs_tcon *tcon,
struct cifs_open_parms oparms;
struct cifs_fid fid;
struct kvec err_iov = {NULL, 0};
-   struct smb2_err_rsp *err_buf = NULL;
+   struct smb2_err_rsp *err_buf;
struct smb2_symlink_err_rsp *symlink;
unsigned int sub_len;
unsigned int sub_offset;
@@ -1476,7 +1476,7 @@ smb2_query_symlink(const unsigned int xid, struct 
cifs_tcon *tcon,
 
rc = SMB2_open(xid, , utf16_path, , NULL, _iov);
 
-   if (!rc || !err_buf) {
+   if (!rc || !err_iov.iov_base) {
kfree(utf16_path);
return -ENOENT;
}
-- 
2.7.4

[PATCH] cifs: smb2ops: Fix NULL check in smb2_query_symlink

[Gustavo A. R. Silva]

The current code null checks variable err_buf, which is always null
when it is checked, hence utf16_path is free'd and the function
returns -ENOENT everytime it is called, making it impossible for the
execution path to reach the following code:

err_buf = err_iov.iov_base;

Fix this by null checking err_iov.iov_base instead of err_buf. Also,
notice that err_buf no longer needs to be initialized to NULL.

Addresses-Coverity-ID: 1467876 ("Logically dead code")
Fixes: 2d636199e400 ("cifs: Change SMB2_open to return an iov for the error 
parameter")
Signed-off-by: Gustavo A. R. Silva 
---
 fs/cifs/smb2ops.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index b4ae932..38ebf3f 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1452,7 +1452,7 @@ smb2_query_symlink(const unsigned int xid, struct 
cifs_tcon *tcon,
struct cifs_open_parms oparms;
struct cifs_fid fid;
struct kvec err_iov = {NULL, 0};
-   struct smb2_err_rsp *err_buf = NULL;
+   struct smb2_err_rsp *err_buf;
struct smb2_symlink_err_rsp *symlink;
unsigned int sub_len;
unsigned int sub_offset;
@@ -1476,7 +1476,7 @@ smb2_query_symlink(const unsigned int xid, struct 
cifs_tcon *tcon,
 
rc = SMB2_open(xid, , utf16_path, , NULL, _iov);
 
-   if (!rc || !err_buf) {
+   if (!rc || !err_iov.iov_base) {
kfree(utf16_path);
return -ENOENT;
}
-- 
2.7.4