The ktrace record for recvmsg/recvfrom could contain extract bits in

msg_flags (they get set internally).  Correct the record to only contain
what the caller requested.

diff --git a/sys/kern/uipc_syscalls.c b/sys/kern/uipc_syscalls.c
index 0b372de..6edae42 100644 (file)
--- a/sys/kern/uipc_syscalls.c
+++ b/sys/kern/uipc_syscalls.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: uipc_syscalls.c,v 1.187 2020/09/29 11:48:54 claudio Exp $     */
+/*     $OpenBSD: uipc_syscalls.c,v 1.188 2021/03/10 17:03:58 deraadt Exp $     */
 /*     $NetBSD: uipc_syscalls.c,v 1.19 1996/02/09 19:00:48 christos Exp $      */
 
 /*
@@ -782,7 +782,7 @@ recvit(struct proc *p, int s, struct msghdr *mp, caddr_t namelenp,
        struct mbuf *from = NULL, *control = NULL;
 #ifdef KTRACE
        struct iovec *ktriov = NULL;
-       int iovlen = 0;
+       int iovlen = 0, kmsgflags;
 #endif
 
        if ((error = getsock(p, s, &fp)) != 0)
@@ -812,6 +812,7 @@ recvit(struct proc *p, int s, struct msghdr *mp, caddr_t namelenp,
 
                memcpy(ktriov, auio.uio_iov, iovlen);
        }
+       kmsgflags = mp->msg_flags;
 #endif
        len = auio.uio_resid;
        if (fp->f_flag & FNONBLOCK)
@@ -873,8 +874,14 @@ recvit(struct proc *p, int s, struct msghdr *mp, caddr_t namelenp,
                                }
                                error = copyout(mtod(m, caddr_t), cp, i);
 #ifdef KTRACE
-                               if (KTRPOINT(p, KTR_STRUCT) && error == 0 && i)
+                               if (KTRPOINT(p, KTR_STRUCT) && error == 0 && i) {
+                                       /* msg_flags potentially incorrect */
+                                       int rmsgflags = mp->msg_flags;
+
+                                       mp->msg_flags = kmsgflags;
                                        ktrcmsghdr(p, mtod(m, char *), i);
+                                       mp->msg_flags = rmsgflags;
+                               }
 #endif
                                if (m->m_next)
                                        i = ALIGN(i);