ppp: mppe: sanity error path rework

We are going to need sanity error path a little further, rework to be
able to use the sanity error path anywhere in decompressor.

Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 16 deletions

diff --git a/drivers/net/ppp/ppp_mppe.c b/drivers/net/ppp/ppp_mppe.c
index 911b21602ff2..692ee0ff0db1 100644
--- a/drivers/net/ppp/ppp_mppe.c
+++ b/drivers/net/ppp/ppp_mppe.c
@@ -478,7 +478,6 @@ mppe_decompress(void *arg, unsigned char *ibuf, int isize, unsigned char *obuf,
         struct blkcipher_desc desc = { .tfm = state->arc4 };
         unsigned ccount;
         int flushed = MPPE_BITS(ibuf) & MPPE_BIT_FLUSHED;
-        int sanity = 0;
         struct scatterlist sg_in[1], sg_out[1];
 
         if (isize <= PPP_HDRLEN + MPPE_OVHD) {
@@ -514,31 +513,19 @@ mppe_decompress(void *arg, unsigned char *ibuf, int isize, unsigned char *obuf,
                        "mppe_decompress[%d]: ENCRYPTED bit not set!\n",
                        state->unit);
                 state->sanity_errors += 100;
-                sanity = 1;
+                goto sanity_error;
         }
         if (!state->stateful && !flushed) {
                 printk(KERN_DEBUG "mppe_decompress[%d]: FLUSHED bit not set in "
                        "stateless mode!\n", state->unit);
                 state->sanity_errors += 100;
-                sanity = 1;
+                goto sanity_error;
         }
         if (state->stateful && ((ccount & 0xff) == 0xff) && !flushed) {
                 printk(KERN_DEBUG "mppe_decompress[%d]: FLUSHED bit not set on "
                        "flag packet!\n", state->unit);
                 state->sanity_errors += 100;
-                sanity = 1;
-        }
-
-        if (sanity) {
-                if (state->sanity_errors < SANITY_MAX)
-                        return DECOMP_ERROR;
-                else
-                        /*
-                         * Take LCP down if the peer is sending too many bogons.
-                         * We don't want to do this for a single or just a few
-                         * instances since it could just be due to packet corruption.
-                         */
-                        return DECOMP_FATALERROR;
+                goto sanity_error;
         }
 
         /*
@@ -649,6 +636,16 @@ mppe_decompress(void *arg, unsigned char *ibuf, int isize, unsigned char *obuf,
         state->sanity_errors >>= 1;
 
         return osize;
+
+sanity_error:
+        if (state->sanity_errors < SANITY_MAX)
+                return DECOMP_ERROR;
+        else
+                /* Take LCP down if the peer is sending too many bogons.
+                 * We don't want to do this for a single or just a few
+                 * instances since it could just be due to packet corruption.
+                 */
+                return DECOMP_FATALERROR;
 }
 
 /*