[Openvpn-devel] sitnl: replace NLMSG_TAIL macro with nlmsg_tail() function
Commit Message
From: Antonio Quartulli <antonio@mandelbit.com>
The NLMSG_TAIL macro never had any reason to exist, because libnl
already provides a function doing exactly the same: nlmsg_tail().
Moreover, this macro was found to confuse gcc when compiling with -O3,
which would result in subsequent warnings like:
networking_sitnl.c:143:9: warning: writing 4 bytes into a region of size 0 [-Wstringop-overflow=]
143 | memcpy(RTA_DATA(rta), data, alen);
| ^
networking_sitnl.c:101:21: note: at offset [72, 88] into destination object ‘n’ of size 16
101 | struct nlmsghdr n;
| ^
(Above warnings are critical on Fedora 40 as they are turned into errors)
Delete the macro, replace it with nlmsg_tail() and get rid of the
warnings.
Signed-off-by: Antonio Quartulli <antonio@mandelbit.com>
---
src/openvpn/networking_sitnl.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
@@ -40,6 +40,7 @@
#include <sys/socket.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
+#include <netlink/msg.h>
#define SNDBUF_SIZE (1024 * 2)
#define RCVBUF_SIZE (1024 * 4)
@@ -52,19 +53,16 @@
} \
}
-#define NLMSG_TAIL(nmsg) \
- ((struct rtattr *)(((uint8_t *)(nmsg)) + NLMSG_ALIGN((nmsg)->nlmsg_len)))
-
#define SITNL_NEST(_msg, _max_size, _attr) \
({ \
- struct rtattr *_nest = NLMSG_TAIL(_msg); \
+ struct rtattr *_nest = nlmsg_tail(_msg); \
SITNL_ADDATTR(_msg, _max_size, _attr, NULL, 0); \
_nest; \
})
#define SITNL_NEST_END(_msg, _nest) \
{ \
- _nest->rta_len = (void *)NLMSG_TAIL(_msg) - (void *)_nest; \
+ _nest->rta_len = (void *)nlmsg_tail(_msg) - (void *)_nest; \
}
/**
@@ -130,7 +128,7 @@ sitnl_addattr(struct nlmsghdr *n, int maxlen, int type, const void *data,
return -EMSGSIZE;
}
- rta = NLMSG_TAIL(n);
+ rta = nlmsg_tail(n);
rta->rta_type = type;
rta->rta_len = len;