[NET]: Reject socket filter if division by constant zero is attempted.

This way we don't have to check it in sk_run_filter().

Signed-off-by: Kris Katterjohn <kjak@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Kris Katterjohn 2005-11-20 13:41:34 -08:00 committed by David S. Miller
parent aa8751667d
commit fb0d366b08

View File

@ -116,8 +116,6 @@ int sk_run_filter(struct sk_buff *skb, struct sock_filter *filter, int flen)
A /= X;
continue;
case BPF_ALU|BPF_DIV|BPF_K:
if (fentry->k == 0)
return 0;
A /= fentry->k;
continue;
case BPF_ALU|BPF_AND|BPF_X:
@ -320,6 +318,10 @@ int sk_chk_filter(struct sock_filter *filter, int flen)
}
}
/* check for division by zero -Kris Katterjohn 2005-10-30 */
if (ftest->code == (BPF_ALU|BPF_DIV|BPF_K) && ftest->k == 0)
return -EINVAL;
/* check that memory operations use valid addresses. */
if (ftest->k >= BPF_MEMWORDS) {
/* but it might not be a memory operation... */