[PPP]: Revert 606f585e363527da9feaed79465132c0c661fd9e
This can cause packet buffer overflows in certain cases,
the real bug will be fixed differently in a followon
changeset.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ppp_mppe.c b/drivers/net/ppp_mppe.c
index 5ae80bb..d5bdd25 100644
--- a/drivers/net/ppp_mppe.c
+++ b/drivers/net/ppp_mppe.c
@@ -493,14 +493,14 @@
/*
* Make sure we have enough room to decrypt the packet.
- * To account for possible PFC we should only subtract 1
- * byte whereas in mppe_compress() we added 2 bytes (+MPPE_OVHD);
- * However, we assume no PFC, thus subtracting 2 bytes.
+ * Note that for our test we only subtract 1 byte whereas in
+ * mppe_compress() we added 2 bytes (+MPPE_OVHD);
+ * this is to account for possible PFC.
*/
- if (osize < isize - MPPE_OVHD - 2) {
+ if (osize < isize - MPPE_OVHD - 1) {
printk(KERN_DEBUG "mppe_decompress[%d]: osize too small! "
"(have: %d need: %d)\n", state->unit,
- osize, isize - MPPE_OVHD - 2);
+ osize, isize - MPPE_OVHD - 1);
return DECOMP_ERROR;
}
osize = isize - MPPE_OVHD - 2; /* assume no PFC */