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>

diff --git a/drivers/net/ppp/ppp_mppe.c b/drivers/net/ppp/ppp_mppe.c
index 911b21602ff271885c2dbfb4c5c04f69fb028e7e..692ee0ff0db1ce9a0be5b36965f9441e7c7ecace 100644 (file)
--- 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;
 }
 
 /*