Correctly sanity-check timer IDs. [SA-09:06]

Limit the size of malloced buffer when dumping environment
variables. [EN-09:01]

Approved by:	so (cperciva)
Approved by:	re (kensmith)
Security:	FreeBSD-SA-09:06.ktimer
Errata:		FreeBSD-EN-09:01.kenv

2 files changed, 9 insertions, 4 deletions

diff --git a/sys/kern/kern_environment.c b/sys/kern/kern_environment.c
index a5658cace2dc..038515b99b05 100644
--- a/sys/kern/kern_environment.c
+++ b/sys/kern/kern_environment.c
@@ -87,7 +87,7 @@ kenv(td, uap)
 	} */ *uap;
 {
 	char *name, *value, *buffer = NULL;
-	size_t len, done, needed;
+	size_t len, done, needed, buflen;
 	int error, i;
 
 	KASSERT(dynamic_kenv, ("kenv: dynamic_kenv = 0"));
@@ -100,13 +100,17 @@ kenv(td, uap)
 			return (error);
 #endif
 		done = needed = 0;
+		buflen = uap->len;
+		if (buflen > KENV_SIZE * (KENV_MNAMELEN + KENV_MVALLEN + 2))
+			buflen = KENV_SIZE * (KENV_MNAMELEN +
+			    KENV_MVALLEN + 2);
 		if (uap->len > 0 && uap->value != NULL)
-			buffer = malloc(uap->len, M_TEMP, M_WAITOK|M_ZERO);
+			buffer = malloc(buflen, M_TEMP, M_WAITOK|M_ZERO);
 		mtx_lock(&kenv_lock);
 		for (i = 0; kenvp[i] != NULL; i++) {
 			len = strlen(kenvp[i]) + 1;
 			needed += len;
-			len = min(len, uap->len - done);
+			len = min(len, buflen - done);
 			/*
 			 * If called with a NULL or insufficiently large
 			 * buffer, just keep computing the required size.
diff --git a/sys/kern/kern_time.c b/sys/kern/kern_time.c
index a8ecace9a868..99c1a53b8853 100644
--- a/sys/kern/kern_time.c
+++ b/sys/kern/kern_time.c
@@ -1085,7 +1085,8 @@ itimer_find(struct proc *p, int timerid)
 	struct itimer *it;
 
 	PROC_LOCK_ASSERT(p, MA_OWNED);
-	if ((p->p_itimers == NULL) || (timerid >= TIMER_MAX) ||
+	if ((p->p_itimers == NULL) ||
+	    (timerid < 0) || (timerid >= TIMER_MAX) ||
 	    (it = p->p_itimers->its_timers[timerid]) == NULL) {
 		return (NULL);
 	}