diff options
| author | Kris Katterjohn <kjak@users.sourceforge.net> | 2005-11-20 13:41:34 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2005-11-20 13:41:34 -0800 |
| commit | fb0d366b0803571f06a5b838f02c6706fc287995 (patch) | |
| tree | 473d0e16f244ef7c7415d865419b7b0187f52a7f | |
| parent | aa8751667dcd757dd9a711b51140adf181501c44 (diff) | |
| download | linux-fb0d366b0803571f06a5b838f02c6706fc287995.tar.bz2 | |
[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>
| -rw-r--r-- | net/core/filter.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/core/filter.c b/net/core/filter.c index 079c2edff789..2841bfce29d6 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -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... */ |