diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2019-01-22 18:18:21 +0000 |
|---|---|---|
| committer | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2019-02-07 15:49:08 +0200 |
| commit | c74e3ae9c83750705abaa583b28741d349364561 (patch) | |
| tree | 2c344866635145a63a12c4891b84f9ed16c15388 /slirp/ip6_icmp.h | |
| parent | 59fa06ac74c1736dd1270fadde6a0077877bea04 (diff) | |
slirp: Avoid marking naturally packed structs as QEMU_PACKED
Various ipv6 structs in the slirp headers are marked QEMU_PACKED,
but they are actually naturally aligned and will have no padding
in them. Instead of marking them with the 'packed' attribute,
assert at compile time that they are the size we expect. This
allows us to take the address of fields within the structs
without risking undefined behaviour, and suppresses clang
-Waddress-of-packed-member warnings.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Diffstat (limited to 'slirp/ip6_icmp.h')
| -rw-r--r-- | slirp/ip6_icmp.h | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/slirp/ip6_icmp.h b/slirp/ip6_icmp.h index 32b0914055..2ad2b75e67 100644 --- a/slirp/ip6_icmp.h +++ b/slirp/ip6_icmp.h @@ -48,12 +48,16 @@ struct ndp_ra { /* Router Advertisement Message */ uint16_t lifetime; /* Router Lifetime */ uint32_t reach_time; /* Reachable Time */ uint32_t retrans_time; /* Retrans Timer */ -} QEMU_PACKED; +}; + +QEMU_BUILD_BUG_ON(sizeof(struct ndp_ra) != 12); struct ndp_ns { /* Neighbor Solicitation Message */ uint32_t reserved; struct in6_addr target; /* Target Address */ -} QEMU_PACKED; +}; + +QEMU_BUILD_BUG_ON(sizeof(struct ndp_ns) != 20); struct ndp_na { /* Neighbor Advertisement Message */ #if G_BYTE_ORDER == G_BIG_ENDIAN @@ -72,13 +76,17 @@ struct ndp_na { /* Neighbor Advertisement Message */ reserved_lo:24; #endif struct in6_addr target; /* Target Address */ -} QEMU_PACKED; +}; + +QEMU_BUILD_BUG_ON(sizeof(struct ndp_na) != 20); struct ndp_redirect { uint32_t reserved; struct in6_addr target; /* Target Address */ struct in6_addr dest; /* Destination Address */ -} QEMU_PACKED; +}; + +QEMU_BUILD_BUG_ON(sizeof(struct ndp_redirect) != 36); /* * Structure of an icmpv6 header. @@ -103,7 +111,9 @@ struct icmp6 { #define icmp6_nns icmp6_body.ndp_ns #define icmp6_nna icmp6_body.ndp_na #define icmp6_redirect icmp6_body.ndp_redirect -} QEMU_PACKED; +}; + +QEMU_BUILD_BUG_ON(sizeof(struct icmp6) != 40); #define ICMP6_MINLEN 4 #define ICMP6_ERROR_MINLEN 8 |