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libnetlink: Use NLMSG_LENGTH to set nlmsg_len

PATCH In review David Ahern 2 participants 2 messages Oct 5, 2018 – Oct 6, 2018

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Networking Network drivers Library code
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David Ahern

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#0 lore raw

PATCH 1/1 libnetlink: Use NLMSG_LENGTH to set nlmsg_len

From: David Ahern <[email protected]>

Some of the inner headers are not 4-byte aligned, so use NLMSG_LENGTH instead of sizeof(req) to set nlmsg_len.

Signed-off-by David Ahern <[email protected]>
---
 lib/libnetlink.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)
lib/libnetlink.c +8 -8
index 9276be29363f..449536197f60 100644
@@ -238,7 +238,7 @@ int rtnl_addrdump_req(struct rtnl_handle *rth, int family)
 		struct nlmsghdr nlh;
 		struct ifaddrmsg ifm;
 	} req = {
-		.nlh.nlmsg_len = sizeof(req),
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
 		.nlh.nlmsg_type = RTM_GETADDR,
 		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 		.nlh.nlmsg_seq = rth->dump = ++rth->seq,

@@ -254,7 +254,7 @@ int rtnl_addrlbldump_req(struct rtnl_handle *rth, int family)
 		struct nlmsghdr nlh;
 		struct ifaddrlblmsg ifal;
 	} req = {
-		.nlh.nlmsg_len = sizeof(req),
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrlblmsg)),
 		.nlh.nlmsg_type = RTM_GETADDRLABEL,
 		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 		.nlh.nlmsg_seq = rth->dump = ++rth->seq,

@@ -296,7 +296,7 @@ int rtnl_ruledump_req(struct rtnl_handle *rth, int family)
 		struct nlmsghdr nlh;
 		struct fib_rule_hdr frh;
 	} req = {
-		.nlh.nlmsg_len = sizeof(req),
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),
 		.nlh.nlmsg_type = RTM_GETRULE,
 		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 		.nlh.nlmsg_seq = rth->dump = ++rth->seq,

@@ -312,7 +312,7 @@ int rtnl_neighdump_req(struct rtnl_handle *rth, int family)
 		struct nlmsghdr nlh;
 		struct ndmsg ndm;
 	} req = {
-		.nlh.nlmsg_len = sizeof(req),
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
 		.nlh.nlmsg_type = RTM_GETNEIGH,
 		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 		.nlh.nlmsg_seq = rth->dump = ++rth->seq,

@@ -328,7 +328,7 @@ int rtnl_neightbldump_req(struct rtnl_handle *rth, int family)
 		struct nlmsghdr nlh;
 		struct ndtmsg ndtmsg;
 	} req = {
-		.nlh.nlmsg_len = sizeof(req),
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndtmsg)),
 		.nlh.nlmsg_type = RTM_GETNEIGHTBL,
 		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 		.nlh.nlmsg_seq = rth->dump = ++rth->seq,

@@ -344,7 +344,7 @@ int rtnl_mdbdump_req(struct rtnl_handle *rth, int family)
 		struct nlmsghdr nlh;
 		struct br_port_msg bpm;
 	} req = {
-		.nlh.nlmsg_len = sizeof(req),
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct br_port_msg)),
 		.nlh.nlmsg_type = RTM_GETMDB,
 		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 		.nlh.nlmsg_seq = rth->dump = ++rth->seq,

@@ -360,7 +360,7 @@ int rtnl_netconfdump_req(struct rtnl_handle *rth, int family)
 		struct nlmsghdr nlh;
 		struct netconfmsg ncm;
 	} req = {
-		.nlh.nlmsg_len = sizeof(req),
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct netconfmsg)),
 		.nlh.nlmsg_type = RTM_GETNETCONF,
 		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 		.nlh.nlmsg_seq = rth->dump = ++rth->seq,

@@ -376,7 +376,7 @@ int rtnl_nsiddump_req(struct rtnl_handle *rth, int family)
 		struct nlmsghdr nlh;
 		struct rtgenmsg rtm;
 	} req = {
-		.nlh.nlmsg_len = sizeof(req),
+		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
 		.nlh.nlmsg_type = RTM_GETNSID,
 		.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 		.nlh.nlmsg_seq = rth->dump = ++rth->seq,
Signature · 1 line
2.11.0
#1 lore raw
Quoted 5 lines · David Ahern

From: David Ahern <[email protected]>

Some of the inner headers are not 4-byte aligned, so use NLMSG_LENGTH instead of sizeof(req) to set nlmsg_len.

this patch is wrong; headers are supposed to be 4-bytes aligned.