sgsnemu: Fix unaligned pointer access during ip/icmp checksum

Catched by gcc 9.1.0:
osmo-ggsn/sgsnemu/sgsnemu.c:1294:2: error: converting a packed struct ip_ping pointer (alignment 1) to a uint16_t {aka short unsigned int} pointer (alignment 2) may result in an unaligned pointer value [-Werror=address-of-packed-member]
 1294 |  p = (uint16_t *) & pack;

Change-Id: I783f104c31234a07f2a13f6dbc577a71b25b36a7
This commit is contained in:
Pau Espin 2019-07-29 18:03:04 +02:00
parent f1e01517bc
commit e47932976c
1 changed files with 12 additions and 8 deletions

View File

@ -1234,7 +1234,7 @@ static int create_ping(void *gsn, struct pdp_t *pdp,
{ {
struct ip_ping pack; struct ip_ping pack;
uint16_t *p = (uint16_t *) & pack; uint16_t v16;
uint8_t *p8 = (uint8_t *) & pack; uint8_t *p8 = (uint8_t *) & pack;
struct in_addr src; struct in_addr src;
unsigned int n; unsigned int n;
@ -1270,7 +1270,7 @@ static int create_ping(void *gsn, struct pdp_t *pdp,
pack.seq = htons(seq); pack.seq = htons(seq);
/* Generate ICMP payload */ /* Generate ICMP payload */
p8 = (uint8_t *) & pack + CREATEPING_IP + CREATEPING_ICMP; p8 = (uint8_t *) &pack + CREATEPING_IP + CREATEPING_ICMP;
for (n = 0; n < (datasize); n++) for (n = 0; n < (datasize); n++)
p8[n] = n; p8[n] = n;
@ -1278,11 +1278,13 @@ static int create_ping(void *gsn, struct pdp_t *pdp,
gettimeofday(tp, &tz); gettimeofday(tp, &tz);
/* Calculate IP header checksum */ /* Calculate IP header checksum */
p = (uint16_t *) & pack; p8 = (uint8_t *) &pack;
count = CREATEPING_IP; count = CREATEPING_IP;
sum = 0; sum = 0;
while (count > 1) { while (count > 1) {
sum += *p++; memcpy(&v16, p8, 2);
sum += v16;
p8 += 2;
count -= 2; count -= 2;
} }
while (sum >> 16) while (sum >> 16)
@ -1292,14 +1294,16 @@ static int create_ping(void *gsn, struct pdp_t *pdp,
/* Calculate ICMP checksum */ /* Calculate ICMP checksum */
count = CREATEPING_ICMP + datasize; /* Length of ICMP message */ count = CREATEPING_ICMP + datasize; /* Length of ICMP message */
sum = 0; sum = 0;
p = (uint16_t *) & pack; p8 = (uint8_t *) &pack;
p += CREATEPING_IP / 2; p8 += CREATEPING_IP;
while (count > 1) { while (count > 1) {
sum += *p++; memcpy(&v16, p8, 2);
sum += v16;
p8 += 2;
count -= 2; count -= 2;
} }
if (count > 0) if (count > 0)
sum += *(unsigned char *)p; sum += *(unsigned char *)p8;
while (sum >> 16) while (sum >> 16)
sum = (sum & 0xffff) + (sum >> 16); sum = (sum & 0xffff) + (sum >> 16);
pack.checksum = ~sum; pack.checksum = ~sum;