SK_CHK_FILTER(9) Linux Networking SK_CHK_FILTER(9)
NAME
sk_chk_filter - verify socket filter code
SYNOPSIS
int sk_chk_filter(struct sock_filter * filter, unsigned int flen);
ARGUMENTS
filter
filter to verify
flen
length of filter
DESCRIPTION
Check the user's filter code. If we let some ugly filter code slip through kaboom! The filter must contain no references or jumps that are
out of range, no illegal instructions, and must end with a RET instruction.
All jumps are forward as they are not signed.
Returns 0 if the rule set is legal or -EINVAL if not.
COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 SK_CHK_FILTER(9)
