net: ipv6: Use struct_size() helper and kcalloc()

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes. Also, remove unnecessary
function ipv6_rpl_srh_alloc_size() and replace kzalloc() with kcalloc(),
which has a 2-factor argument form for multiplication.

This code was detected with the help of Coccinelle and, audited and
fixed manually.

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Gustavo A. R. Silva 2020-06-22 18:07:41 -05:00 committed by David S. Miller
parent 5777cbba79
commit 6f39345768
3 changed files with 2 additions and 9 deletions

View File

@ -26,12 +26,6 @@ static inline void rpl_exit(void) {}
/* Worst decompression memory usage ipv6 address (16) + pad 7 */
#define IPV6_RPL_SRH_WORST_SWAP_SIZE (sizeof(struct in6_addr) + 7)
static inline size_t ipv6_rpl_srh_alloc_size(unsigned char n)
{
return sizeof(struct ipv6_rpl_sr_hdr) +
((n + 1) * sizeof(struct in6_addr));
}
size_t ipv6_rpl_srh_size(unsigned char n, unsigned char cmpri,
unsigned char cmpre);

View File

@ -580,7 +580,7 @@ static int ipv6_rpl_srh_rcv(struct sk_buff *skb)
hdr->segments_left--;
i = n - hdr->segments_left;
buf = kzalloc(ipv6_rpl_srh_alloc_size(n + 1) * 2, GFP_ATOMIC);
buf = kcalloc(struct_size(hdr, segments.addr, n + 2), 2, GFP_ATOMIC);
if (unlikely(!buf)) {
kfree_skb(skb);
return -1;

View File

@ -136,8 +136,7 @@ static int rpl_do_srh_inline(struct sk_buff *skb, const struct rpl_lwt *rlwt,
oldhdr = ipv6_hdr(skb);
buf = kzalloc(ipv6_rpl_srh_alloc_size(srh->segments_left - 1) * 2,
GFP_ATOMIC);
buf = kcalloc(struct_size(srh, segments.addr, srh->segments_left), 2, GFP_ATOMIC);
if (!buf)
return -ENOMEM;