[PATCH RESEND -next] lsm_audit: Clean up redundant NULL pointer check

From: Xiu Jianfeng
Date: Wed Jul 13 2022 - 21:27:30 EST


The implements of {ip,tcp,udp,dccp,sctp,ipv6}_hdr(skb) guarantee that
they will never return NULL, and elsewhere users don't do the check
as well, so remove the check here.

Signed-off-by: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>
---
security/lsm_audit.c | 14 +-------------
1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/security/lsm_audit.c b/security/lsm_audit.c
index 78a278f28e49..75cc3f8d2a42 100644
--- a/security/lsm_audit.c
+++ b/security/lsm_audit.c
@@ -44,9 +44,6 @@ int ipv4_skb_to_auditdata(struct sk_buff *skb,
struct iphdr *ih;

ih = ip_hdr(skb);
- if (ih == NULL)
- return -EINVAL;
-
ad->u.net->v4info.saddr = ih->saddr;
ad->u.net->v4info.daddr = ih->daddr;

@@ -59,8 +56,6 @@ int ipv4_skb_to_auditdata(struct sk_buff *skb,
switch (ih->protocol) {
case IPPROTO_TCP: {
struct tcphdr *th = tcp_hdr(skb);
- if (th == NULL)
- break;

ad->u.net->sport = th->source;
ad->u.net->dport = th->dest;
@@ -68,8 +63,6 @@ int ipv4_skb_to_auditdata(struct sk_buff *skb,
}
case IPPROTO_UDP: {
struct udphdr *uh = udp_hdr(skb);
- if (uh == NULL)
- break;

ad->u.net->sport = uh->source;
ad->u.net->dport = uh->dest;
@@ -77,8 +70,6 @@ int ipv4_skb_to_auditdata(struct sk_buff *skb,
}
case IPPROTO_DCCP: {
struct dccp_hdr *dh = dccp_hdr(skb);
- if (dh == NULL)
- break;

ad->u.net->sport = dh->dccph_sport;
ad->u.net->dport = dh->dccph_dport;
@@ -86,8 +77,7 @@ int ipv4_skb_to_auditdata(struct sk_buff *skb,
}
case IPPROTO_SCTP: {
struct sctphdr *sh = sctp_hdr(skb);
- if (sh == NULL)
- break;
+
ad->u.net->sport = sh->source;
ad->u.net->dport = sh->dest;
break;
@@ -115,8 +105,6 @@ int ipv6_skb_to_auditdata(struct sk_buff *skb,
__be16 frag_off;

ip6 = ipv6_hdr(skb);
- if (ip6 == NULL)
- return -EINVAL;
ad->u.net->v6info.saddr = ip6->saddr;
ad->u.net->v6info.daddr = ip6->daddr;
/* IPv6 can have several extension header before the Transport header
--
2.17.1