net: filter: sk_chk_filter() no longer mangles filter

Add const attribute to filter argument to make clear it is no
longer modified.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 3 deletions

diff --git a/net/core/filter.c b/net/core/filter.c
index 87af1e3e56c0..b90ae7fb3b89 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -1085,7 +1085,7 @@ err:
  * a cell if not previously written, and we check all branches to be sure
  * a malicious user doesn't try to abuse us.
  */
-static int check_load_and_stores(struct sock_filter *filter, int flen)
+static int check_load_and_stores(const struct sock_filter *filter, int flen)
 {
         u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
         int pc, ret = 0;
@@ -1218,7 +1218,7 @@ static bool chk_code_allowed(u16 code_to_probe)
  *
  * Returns 0 if the rule set is legal or -EINVAL if not.
  */
-int sk_chk_filter(struct sock_filter *filter, unsigned int flen)
+int sk_chk_filter(const struct sock_filter *filter, unsigned int flen)
 {
         bool anc_found;
         int pc;
@@ -1228,7 +1228,7 @@ int sk_chk_filter(struct sock_filter *filter, unsigned int flen)
 
         /* Check the filter code now */
         for (pc = 0; pc < flen; pc++) {
-                struct sock_filter *ftest = &filter[pc];
+                const struct sock_filter *ftest = &filter[pc];
 
                 /* May we actually operate on this code? */
                 if (!chk_code_allowed(ftest->code))