diff options
author | Ben Hutchings <ben@decadent.org.uk> | 2016-01-22 20:57:34 +0000 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2016-01-28 15:48:06 +0000 |
commit | 687b3c65c0460dd8c4ba7e63e3ae0ab20836e6e8 (patch) | |
tree | 2b54573e649124945a74665cd3b9c38dd5d052a3 /src | |
parent | 8a8005f7ca8973702b36e711993bfff89ca9600c (diff) | |
download | odhcp6c-687b3c65c0460dd8c4ba7e63e3ae0ab20836e6e8.tar.gz |
Fix alignment of buffers in ra_process and dhcpv6_request
The packet buffer needs to be 32-bit aligned to ensure that the various
32-bit fields we pick out are naturally aligned.
The control message buffers needs to be naturally aligned for struct
cmsghdr.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'src')
-rw-r--r-- | src/dhcpv6.c | 4 | ||||
-rw-r--r-- | src/odhcp6c.h | 1 | ||||
-rw-r--r-- | src/ra.c | 3 |
3 files changed, 6 insertions, 2 deletions
diff --git a/src/dhcpv6.c b/src/dhcpv6.c index e27d899..8a1231d 100644 --- a/src/dhcpv6.c +++ b/src/dhcpv6.c @@ -577,7 +577,9 @@ int dhcpv6_request(enum dhcpv6_msg type) // Receive rounds for (; len < 0 && (round_start < round_end); round_start = odhcp6c_get_milli_time()) { - uint8_t buf[1536], cmsg_buf[CMSG_SPACE(sizeof(struct in6_pktinfo))]; + uint8_t buf[1536]; + uint8_t cmsg_buf[CMSG_SPACE(sizeof(struct in6_pktinfo))] + __aligned(__alignof__(struct cmsghdr)); struct iovec iov = {buf, sizeof(buf)}; struct sockaddr_in6 addr; struct msghdr msg = {.msg_name = &addr, .msg_namelen = sizeof(addr), diff --git a/src/odhcp6c.h b/src/odhcp6c.h index 98d91dd..08a816f 100644 --- a/src/odhcp6c.h +++ b/src/odhcp6c.h @@ -18,6 +18,7 @@ #define _unused __attribute__((unused)) #define _packed __attribute__((packed)) +#define __aligned(n) __attribute__((aligned(n))) #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) @@ -274,7 +274,8 @@ bool ra_process(void) { bool found = false; bool changed = false; - uint8_t buf[1500], cmsg_buf[128]; + uint8_t buf[1500] __aligned(4); + uint8_t cmsg_buf[128] __aligned(__alignof__(struct cmsghdr)); struct nd_router_advert *adv = (struct nd_router_advert*)buf; struct odhcp6c_entry *entry = alloca(sizeof(*entry) + 256); const struct in6_addr any = IN6ADDR_ANY_INIT; |