@@ -421,7 +421,7 @@ find_domain_name(struct cifs_ses *ses, const
struct nls_table *nls_cp)
if (blobptr + attrsize > blobend)
break;
if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
- if (!attrsize)
+ if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
break;
if (!ses->domainName) {
ses->domainName =
@@ -44,6 +44,7 @@
#define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
#define MAX_SERVER_SIZE 15
#define MAX_SHARE_SIZE 80
+#define CIFS_MAX_DOMAINNAME_LEN 256 /* max domain name length */
#define MAX_USERNAME_SIZE 256 /* reasonable maximum for current servers */
#define MAX_PASSWORD_SIZE 512 /* max for windows seems to be 256 wide chars */
@@ -1675,7 +1675,8 @@ cifs_parse_mount_options(const char *mountdata,
const char *devname,
if (string == NULL)
goto out_nomem;
- if (strnlen(string, 256) == 256) {
+ if (strnlen(string, CIFS_MAX_DOMAINNAME_LEN)
+ == CIFS_MAX_DOMAINNAME_LEN) {
printk(KERN_WARNING "CIFS: domain name too"
" long\n");
goto cifs_parse_mount_err;
@@ -2276,8 +2277,8 @@ cifs_put_smb_ses(struct cifs_ses *ses)
#ifdef CONFIG_KEYS
-/* strlen("cifs:a:") + INET6_ADDRSTRLEN + 1 */
-#define CIFSCREDS_DESC_SIZE (7 + INET6_ADDRSTRLEN + 1)
+/* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
+#define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
/* Populate username and pw fields from keyring if possible */
static int
@@ -197,7 +197,7 @@ static void unicode_domain_string(char
**pbcc_area, struct cifs_ses *ses,
bytes_ret = 0;
} else
bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
- 256, nls_cp);
+ CIFS_MAX_DOMAINNAME_LEN, nls_cp);
bcc_ptr += 2 * bytes_ret;
bcc_ptr += 2; /* account for null terminator */
I updated the version of the patch slightly which is in cifs-2.6.git so we don't have to rename the MAX_DOMAINNAME_SIZE field multiple times. Let me know if you see problems. It could make Scott's followup patch a little easier to understand without the renamed #define. commit 057d6332b24a4497c55a761c83c823eed9e3f23b Author: Chen Gang <gang.chen@asianux.com> Date: Fri Jul 19 09:01:36 2013 +0800 cifs: extend the buffer length enought for sprintf() using For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName' length may be "255 + '\0'". The related sprintf() may cause memory overflow, so need extend related buffer enough to hold all things. It is also necessary to be sure of 'ses->domainName' must be less than 256, and define the related macro instead of hard code number '256'. Signed-off-by: Chen Gang <gang.chen@asianux.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Reviewed-by: Scott Lovenberg <scott.lovenberg@gmail.com> CC: <stable@vger.kernel.org> Signed-off-by: Steve French <smfrench@gmail.com> @@ -255,8 +255,8 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses, /* copy domain */ if (ses->domainName != NULL) { - strncpy(bcc_ptr, ses->domainName, 256); - bcc_ptr += strnlen(ses->domainName, 256); + strncpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN); + bcc_ptr += strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN); } /* else we will send a null domain name so the server will default to its own domain */ *bcc_ptr = 0; On Sun, Jul 21, 2013 at 8:21 PM, Chen Gang <gang.chen@asianux.com> wrote: > On 07/19/2013 11:46 PM, Steve French wrote: >> merged into cifs-2.6.git >> > > Thanks. > >> On Fri, Jul 19, 2013 at 5:45 AM, Jeff Layton <jlayton@redhat.com> wrote: >>> > On Fri, 19 Jul 2013 09:01:36 +0800 >>> > Chen Gang <gang.chen@asianux.com> wrote: >>> > >>>> >> For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length >>>> >> is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName' >>>> >> length may be "255 + '\0'". >>>> >> >>>> >> The related sprintf() may cause memory overflow, so need extend related >>>> >> buffer enough to hold all things. >>>> >> >>>> >> It is also necessary to be sure of 'ses->domainName' must be less than >>>> >> 256, and define the related macro instead of hard code number '256'. >>>> >> >>>> >> Signed-off-by: Chen Gang <gang.chen@asianux.com> >>>> >> --- >>>> >> fs/cifs/cifsencrypt.c | 2 +- >>>> >> fs/cifs/cifsglob.h | 1 + >>>> >> fs/cifs/connect.c | 7 ++++--- >>>> >> fs/cifs/sess.c | 6 +++--- >>>> >> 4 files changed, 9 insertions(+), 7 deletions(-) >>>> >> >>>> >> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c >>>> >> index 45e57cc..bb84d7c 100644 >>>> >> --- a/fs/cifs/cifsencrypt.c >>>> >> +++ b/fs/cifs/cifsencrypt.c >>>> >> @@ -421,7 +421,7 @@ find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp) >>>> >> if (blobptr + attrsize > blobend) >>>> >> break; >>>> >> if (type == NTLMSSP_AV_NB_DOMAIN_NAME) { >>>> >> - if (!attrsize) >>>> >> + if (!attrsize || attrsize >= MAX_DOMAINNAME_SIZE) >>>> >> break; >>>> >> if (!ses->domainName) { >>>> >> ses->domainName = >>>> >> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h >>>> >> index 33f17ed..64bb4c5 100644 >>>> >> --- a/fs/cifs/cifsglob.h >>>> >> +++ b/fs/cifs/cifsglob.h >>>> >> @@ -44,6 +44,7 @@ >>>> >> #define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1) >>>> >> #define MAX_SERVER_SIZE 15 >>>> >> #define MAX_SHARE_SIZE 80 >>>> >> +#define MAX_DOMAINNAME_SIZE 256 /* maximum fully qualified domain name (FQDN) */ >>>> >> #define MAX_USERNAME_SIZE 256 /* reasonable maximum for current servers */ >>>> >> #define MAX_PASSWORD_SIZE 512 /* max for windows seems to be 256 wide chars */ >>>> >> >>>> >> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c >>>> >> index fa68813..3f9dcf7 100644 >>>> >> --- a/fs/cifs/connect.c >>>> >> +++ b/fs/cifs/connect.c >>>> >> @@ -1675,7 +1675,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname, >>>> >> if (string == NULL) >>>> >> goto out_nomem; >>>> >> >>>> >> - if (strnlen(string, 256) == 256) { >>>> >> + if (strnlen(string, MAX_DOMAINNAME_SIZE) >>>> >> + == MAX_DOMAINNAME_SIZE) { >>>> >> printk(KERN_WARNING "CIFS: domain name too" >>>> >> " long\n"); >>>> >> goto cifs_parse_mount_err; >>>> >> @@ -2276,8 +2277,8 @@ cifs_put_smb_ses(struct cifs_ses *ses) >>>> >> >>>> >> #ifdef CONFIG_KEYS >>>> >> >>>> >> -/* strlen("cifs:a:") + INET6_ADDRSTRLEN + 1 */ >>>> >> -#define CIFSCREDS_DESC_SIZE (7 + INET6_ADDRSTRLEN + 1) >>>> >> +/* strlen("cifs:a:") + MAX_DOMAINNAME_SIZE + 1 */ >>>> >> +#define CIFSCREDS_DESC_SIZE (7 + MAX_DOMAINNAME_SIZE + 1) >>>> >> >>>> >> /* Populate username and pw fields from keyring if possible */ >>>> >> static int >>>> >> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c >>>> >> index 79358e3..57b1537 100644 >>>> >> --- a/fs/cifs/sess.c >>>> >> +++ b/fs/cifs/sess.c >>>> >> @@ -197,7 +197,7 @@ static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses, >>>> >> bytes_ret = 0; >>>> >> } else >>>> >> bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName, >>>> >> - 256, nls_cp); >>>> >> + MAX_DOMAINNAME_SIZE, nls_cp); >>>> >> bcc_ptr += 2 * bytes_ret; >>>> >> bcc_ptr += 2; /* account for null terminator */ >>>> >> >>>> >> @@ -255,8 +255,8 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses, >>>> >> >>>> >> /* copy domain */ >>>> >> if (ses->domainName != NULL) { >>>> >> - strncpy(bcc_ptr, ses->domainName, 256); >>>> >> - bcc_ptr += strnlen(ses->domainName, 256); >>>> >> + strncpy(bcc_ptr, ses->domainName, MAX_DOMAINNAME_SIZE); >>>> >> + bcc_ptr += strnlen(ses->domainName, MAX_DOMAINNAME_SIZE); >>>> >> } /* else we will send a null domain name >>>> >> so the server will default to its own domain */ >>>> >> *bcc_ptr = 0; >>> > >>> > Looks good... >>> > >>> > Reviewed-by: Jeff Layton <jlayton@redhat.com> >> >> >> -- Thanks, Steve >> > > > -- > Chen Gang