From: Jouni Malinen <j@w1.fi>
Date: Tue, 7 Jul 2015 10:04:08 +0000 (+0300)
Subject: trace: Use explicit alignment requirements to avoid misalignment
X-Git-Tag: hostap_2_5~466
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e01281fccc666e121dc5846dad85327bae6e9517;p=thirdparty%2Fhostap.git

trace: Use explicit alignment requirements to avoid misalignment

64-bit builds with CONFIG_WPA_TRACE=y resulted in the wpabuf pointers
getting misaligned (only 32-bit aligned) and that would result in reads
and writes of unaligned size_t values. Avoid this by indicating explicit
alignment requirement for wpabuf_trace to 8 octets (i.e., there will be
extra four octets of padding in case of 64-bit builds).

Similarly, struct os_alloc_trace resulted in some potential misalignment
cases, e.g., when CONFIG_ACS=y uses a 'long double' variable within
struct hostapd_channel_data. Avoid misalignment issues with explicit
alignment indication.

Signed-off-by: Jouni Malinen <j@w1.fi>
---

diff --git a/src/utils/os_unix.c b/src/utils/os_unix.c
index e4259042a..089b880bd 100644
--- a/src/utils/os_unix.c
+++ b/src/utils/os_unix.c
@@ -36,7 +36,7 @@ struct os_alloc_trace {
 	struct dl_list list;
 	size_t len;
 	WPA_TRACE_INFO
-};
+} __attribute__((aligned(16)));
 
 #endif /* WPA_TRACE */
 
diff --git a/src/utils/wpabuf.c b/src/utils/wpabuf.c
index 7aafa0a51..11e732361 100644
--- a/src/utils/wpabuf.c
+++ b/src/utils/wpabuf.c
@@ -17,7 +17,7 @@
 
 struct wpabuf_trace {
 	unsigned int magic;
-};
+} __attribute__((aligned(8)));
 
 static struct wpabuf_trace * wpabuf_get_trace(const struct wpabuf *buf)
 {