git: 3e27fcf05793 - stable/13 - inpcb: Remove NULL checks of credential references

The branch stable/13 has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=3e27fcf057937ef93258dc4f8e67a308e02f349c

commit 3e27fcf057937ef93258dc4f8e67a308e02f349c
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2022-11-02 17:03:41 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2024-01-22 18:45:03 +0000

    inpcb: Remove NULL checks of credential references
    
    Some auditing of the code shows that "cred" is never non-NULL in these
    functions, either because all callers pass a non-NULL reference or
    because they unconditionally dereference "cred".  So, let's simplify the
    code a bit and remove NULL checks.  No functional change intended.
    
    Reviewed by:    glebius
    MFC after:      1 week
    Sponsored by:   Modirum MDPay
    Sponsored by:   Klara, Inc.
    Differential Revision:  https://reviews.freebsd.org/D37025
    
    (cherry picked from commit ac1750dd143e53225c518bc1ca0462c3fffe10f6)
---
 sys/netinet/in_pcb.c   | 27 ++++++++++++---------------
 sys/netinet6/in6_pcb.c | 10 ++++------
 2 files changed, 16 insertions(+), 21 deletions(-)

diff --git a/sys/netinet/in_pcb.c b/sys/netinet/in_pcb.c
index 61079db56bdb..3f4ad6752aae 100644
--- a/sys/netinet/in_pcb.c
+++ b/sys/netinet/in_pcb.c
@@ -1154,11 +1154,12 @@ in_pcbladdr(struct inpcb *inp, struct in_addr *faddr, struct in_addr *laddr,
 
 	NET_EPOCH_ASSERT();
 	KASSERT(laddr != NULL, ("%s: laddr NULL", __func__));
+
 	/*
 	 * Bypass source address selection and use the primary jail IP
 	 * if requested.
 	 */
-	if (cred != NULL && !prison_saddrsel_ip4(cred, laddr))
+	if (!prison_saddrsel_ip4(cred, laddr))
 		return (0);
 
 	error = 0;
@@ -1203,7 +1204,7 @@ in_pcbladdr(struct inpcb *inp, struct in_addr *faddr, struct in_addr *laddr,
 			goto done;
 		}
 
-		if (cred == NULL || !prison_flag(cred, PR_IP4)) {
+		if (!prison_flag(cred, PR_IP4)) {
 			laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
 			goto done;
 		}
@@ -1244,7 +1245,7 @@ in_pcbladdr(struct inpcb *inp, struct in_addr *faddr, struct in_addr *laddr,
 		struct ifnet *ifp;
 
 		/* If not jailed, use the default returned. */
-		if (cred == NULL || !prison_flag(cred, PR_IP4)) {
+		if (!prison_flag(cred, PR_IP4)) {
 			ia = (struct in_ifaddr *)nh->nh_ifa;
 			laddr->s_addr = ia->ia_addr.sin_addr.s_addr;
 			goto done;
@@ -1305,7 +1306,7 @@ in_pcbladdr(struct inpcb *inp, struct in_addr *faddr, struct in_addr *laddr,
 		if (ia == NULL)
 			ia = ifatoia(ifa_ifwithaddr(sintosa(&dst)));
 
-		if (cred == NULL || !prison_flag(cred, PR_IP4)) {
+		if (!prison_flag(cred, PR_IP4)) {
 			if (ia == NULL) {
 				error = ENETUNREACH;
 				goto done;
@@ -1421,8 +1422,7 @@ in_pcbconnect_setup(struct inpcb *inp, struct sockaddr *nam,
 			faddr =
 			    IA_SIN(CK_STAILQ_FIRST(&V_in_ifaddrhead))->sin_addr;
 			IN_IFADDR_RUNLOCK(&in_ifa_tracker);
-			if (cred != NULL &&
-			    (error = prison_get_ip4(cred, &faddr)) != 0)
+			if ((error = prison_get_ip4(cred, &faddr)) != 0)
 				return (error);
 		} else if (faddr.s_addr == (u_long)INADDR_BROADCAST) {
 			IN_IFADDR_RLOCK(&in_ifa_tracker);
@@ -1450,10 +1450,9 @@ in_pcbconnect_setup(struct inpcb *inp, struct sockaddr *nam,
 				ifp = imo->imo_multicast_ifp;
 				IN_IFADDR_RLOCK(&in_ifa_tracker);
 				CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
-					if ((ia->ia_ifp == ifp) &&
-					    (cred == NULL ||
+					if (ia->ia_ifp == ifp &&
 					    prison_check_ip4(cred,
-					    &ia->ia_addr.sin_addr) == 0))
+					    &ia->ia_addr.sin_addr) == 0)
 						break;
 				}
 				if (ia == NULL)
@@ -2006,9 +2005,8 @@ in_pcblookup_local(struct inpcbinfo *pcbinfo, struct in_addr laddr,
 				/*
 				 * Found?
 				 */
-				if (cred == NULL ||
-				    prison_equal_ip4(cred->cr_prison,
-					inp->inp_cred->cr_prison))
+				if (prison_equal_ip4(cred->cr_prison,
+				    inp->inp_cred->cr_prison))
 					return (inp);
 			}
 		}
@@ -2039,9 +2037,8 @@ in_pcblookup_local(struct inpcbinfo *pcbinfo, struct in_addr laddr,
 			 */
 			CK_LIST_FOREACH(inp, &phd->phd_pcblist, inp_portlist) {
 				wildcard = 0;
-				if (cred != NULL &&
-				    !prison_equal_ip4(inp->inp_cred->cr_prison,
-					cred->cr_prison))
+				if (!prison_equal_ip4(inp->inp_cred->cr_prison,
+				    cred->cr_prison))
 					continue;
 #ifdef INET6
 				/* XXX inp locking */
diff --git a/sys/netinet6/in6_pcb.c b/sys/netinet6/in6_pcb.c
index a153b06a7435..6d7c1d4b65b5 100644
--- a/sys/netinet6/in6_pcb.c
+++ b/sys/netinet6/in6_pcb.c
@@ -764,9 +764,8 @@ in6_pcblookup_local(struct inpcbinfo *pcbinfo, struct in6_addr *laddr,
 			    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, laddr) &&
 			    inp->inp_lport == lport) {
 				/* Found. */
-				if (cred == NULL ||
-				    prison_equal_ip6(cred->cr_prison,
-					inp->inp_cred->cr_prison))
+				if (prison_equal_ip6(cred->cr_prison,
+				    inp->inp_cred->cr_prison))
 					return (inp);
 			}
 		}
@@ -797,9 +796,8 @@ in6_pcblookup_local(struct inpcbinfo *pcbinfo, struct in6_addr *laddr,
 			 */
 			CK_LIST_FOREACH(inp, &phd->phd_pcblist, inp_portlist) {
 				wildcard = 0;
-				if (cred != NULL &&
-				    !prison_equal_ip6(cred->cr_prison,
-					inp->inp_cred->cr_prison))
+				if (!prison_equal_ip6(cred->cr_prison,
+				    inp->inp_cred->cr_prison))
 					continue;
 				/* XXX inp locking */
 				if ((inp->inp_vflag & INP_IPV6) == 0)