2 files changed, 9 insertions, 5 deletions

diff --git a/kernel/drivers/net/slip/slhc.c b/kernel/drivers/net/slip/slhc.c
index 079f7adfc..27ed25252 100644
--- a/kernel/drivers/net/slip/slhc.c
+++ b/kernel/drivers/net/slip/slhc.c
@@ -84,8 +84,9 @@ static long decode(unsigned char **cpp);
 static unsigned char * put16(unsigned char *cp, unsigned short x);
 static unsigned short pull16(unsigned char **cpp);
 
-/* Initialize compression data structure
+/* Allocate compression data structure
  *	slots must be in range 0 to 255 (zero meaning no compression)
+ * Returns pointer to structure or ERR_PTR() on error.
  */
 struct slcompress *
 slhc_init(int rslots, int tslots)
@@ -94,11 +95,14 @@ slhc_init(int rslots, int tslots)
 	register struct cstate *ts;
 	struct slcompress *comp;
 
+	if (rslots < 0 || rslots > 255 || tslots < 0 || tslots > 255)
+		return ERR_PTR(-EINVAL);
+
 	comp = kzalloc(sizeof(struct slcompress), GFP_KERNEL);
 	if (! comp)
 		goto out_fail;
 
-	if ( rslots > 0  &&  rslots < 256 ) {
+	if (rslots > 0) {
 		size_t rsize = rslots * sizeof(struct cstate);
 		comp->rstate = kzalloc(rsize, GFP_KERNEL);
 		if (! comp->rstate)
@@ -106,7 +110,7 @@ slhc_init(int rslots, int tslots)
 		comp->rslot_limit = rslots - 1;
 	}
 
-	if ( tslots > 0  &&  tslots < 256 ) {
+	if (tslots > 0) {
 		size_t tsize = tslots * sizeof(struct cstate);
 		comp->tstate = kzalloc(tsize, GFP_KERNEL);
 		if (! comp->tstate)
@@ -141,7 +145,7 @@ out_free2:
 out_free:
 	kfree(comp);
 out_fail:
-	return NULL;
+	return ERR_PTR(-ENOMEM);
 }
 
 
diff --git a/kernel/drivers/net/slip/slip.c b/kernel/drivers/net/slip/slip.c
index 05387b1e2..a17d86a57 100644
--- a/kernel/drivers/net/slip/slip.c
+++ b/kernel/drivers/net/slip/slip.c
@@ -164,7 +164,7 @@ static int sl_alloc_bufs(struct slip *sl, int mtu)
 	if (cbuff == NULL)
 		goto err_exit;
 	slcomp = slhc_init(16, 16);
-	if (slcomp == NULL)
+	if (IS_ERR(slcomp))
 		goto err_exit;
 #endif
 	spin_lock_bh(&sl->lock);