[PATCH 3.18 19/50] isdn/i4l: fix buffer overflow

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

--

From: Annie Cherkaev 

commit 9f5af546e6acc30f075828cb58c7f09665033967 upstream.

This fixes a potential buffer overflow in isdn_net.c caused by an
unbounded strcpy.

[ ISDN seems to be effectively unmaintained, and the I4L driver in
  particular is long deprecated, but in case somebody uses this..
- Linus ]

Signed-off-by: Jiten Thakkar 
Signed-off-by: Annie Cherkaev 
Cc: Karsten Keil 
Cc: Kees Cook 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman 

---
 drivers/isdn/i4l/isdn_common.c |1 +
 drivers/isdn/i4l/isdn_net.c|5 ++---
 2 files changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/isdn/i4l/isdn_common.c
+++ b/drivers/isdn/i4l/isdn_common.c
@@ -1379,6 +1379,7 @@ isdn_ioctl(struct file *file, uint cmd,
if (arg) {
if (copy_from_user(bname, argp, sizeof(bname) - 
1))
return -EFAULT;
+   bname[sizeof(bname)-1] = 0;
} else
return -EINVAL;
ret = mutex_lock_interruptible(>mtx);
--- a/drivers/isdn/i4l/isdn_net.c
+++ b/drivers/isdn/i4l/isdn_net.c
@@ -2644,10 +2644,9 @@ isdn_net_newslave(char *parm)
char newname[10];
 
if (p) {
-   /* Slave-Name MUST not be empty */
-   if (!strlen(p + 1))
+   /* Slave-Name MUST not be empty or overflow 'newname' */
+   if (strscpy(newname, p + 1, sizeof(newname)) <= 0)
return NULL;
-   strcpy(newname, p + 1);
*p = 0;
/* Master must already exist */
if (!(n = isdn_net_findif(parm)))

[PATCH 3.18 19/50] isdn/i4l: fix buffer overflow

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

--

From: Annie Cherkaev 

commit 9f5af546e6acc30f075828cb58c7f09665033967 upstream.

This fixes a potential buffer overflow in isdn_net.c caused by an
unbounded strcpy.

[ ISDN seems to be effectively unmaintained, and the I4L driver in
  particular is long deprecated, but in case somebody uses this..
- Linus ]

Signed-off-by: Jiten Thakkar 
Signed-off-by: Annie Cherkaev 
Cc: Karsten Keil 
Cc: Kees Cook 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman 

---
 drivers/isdn/i4l/isdn_common.c |1 +
 drivers/isdn/i4l/isdn_net.c|5 ++---
 2 files changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/isdn/i4l/isdn_common.c
+++ b/drivers/isdn/i4l/isdn_common.c
@@ -1379,6 +1379,7 @@ isdn_ioctl(struct file *file, uint cmd,
if (arg) {
if (copy_from_user(bname, argp, sizeof(bname) - 
1))
return -EFAULT;
+   bname[sizeof(bname)-1] = 0;
} else
return -EINVAL;
ret = mutex_lock_interruptible(>mtx);
--- a/drivers/isdn/i4l/isdn_net.c
+++ b/drivers/isdn/i4l/isdn_net.c
@@ -2644,10 +2644,9 @@ isdn_net_newslave(char *parm)
char newname[10];
 
if (p) {
-   /* Slave-Name MUST not be empty */
-   if (!strlen(p + 1))
+   /* Slave-Name MUST not be empty or overflow 'newname' */
+   if (strscpy(newname, p + 1, sizeof(newname)) <= 0)
return NULL;
-   strcpy(newname, p + 1);
*p = 0;
/* Master must already exist */
if (!(n = isdn_net_findif(parm)))