Revised SA-16:15. The initial patch didn't cover all possible overflows

based on passing incorrect parameters to sysarch(2). [1]

Fix unchecked array reference in the VGA device emulation code. [2]

Security:	SA-16:15 [1]
Security:       SA-16:32 [2]
Approved by:	so

4 files changed, 15 insertions, 6 deletions

diff --git a/UPDATING b/UPDATING
index be8f6d2..74e7ecd 100644
--- a/UPDATING
+++ b/UPDATING
@@ -16,6 +16,12 @@ from older versions of FreeBSD, try WITHOUT_CLANG and WITH_GCC to bootstrap to
 the tip of head, and then rebuild without this option. The bootstrap process
 from older version of current across the gcc/clang cutover is a bit fragile.
 
+20161025	p2	FreeBSD-SA-16:15.sysarch [revised]
+			FreeBSD-SA-16:32.bhyve
+
+	Fix incorrect argument validation in sysarch(2). [SA-16:15]
+	Fix access to host memory from guest in bhyve(8). [SA-16:32]
+
 20160928:
 	11.0-RELEASE.
 
diff --git a/sys/amd64/amd64/sys_machdep.c b/sys/amd64/amd64/sys_machdep.c
index 4f85e1f..24009db 100644
--- a/sys/amd64/amd64/sys_machdep.c
+++ b/sys/amd64/amd64/sys_machdep.c
@@ -608,6 +608,8 @@ amd64_set_ldt(td, uap, descs)
 		largest_ld = uap->start + uap->num;
 		if (largest_ld > max_ldt_segment)
 			largest_ld = max_ldt_segment;
+		if (largest_ld < uap->start)
+			return (EINVAL);
 		i = largest_ld - uap->start;
 		mtx_lock(&dt_lock);
 		bzero(&((struct user_segment_descriptor *)(pldt->ldt_base))
@@ -620,7 +622,8 @@ amd64_set_ldt(td, uap, descs)
 		/* verify range of descriptors to modify */
 		largest_ld = uap->start + uap->num;
 		if (uap->start >= max_ldt_segment ||
-		    largest_ld > max_ldt_segment)
+		    largest_ld > max_ldt_segment ||
+		    largest_ld < uap->start)
 			return (EINVAL);
 	}
 
diff --git a/sys/conf/newvers.sh b/sys/conf/newvers.sh
index 822c8979..f734ad1 100644
--- a/sys/conf/newvers.sh
+++ b/sys/conf/newvers.sh
@@ -32,7 +32,7 @@
 
 TYPE="FreeBSD"
 REVISION="11.0"
-BRANCH="RELEASE-p1"
+BRANCH="RELEASE-p2"
 if [ -n "${BRANCH_OVERRIDE}" ]; then
 	BRANCH=${BRANCH_OVERRIDE}
 fi
diff --git a/usr.sbin/bhyve/vga.c b/usr.sbin/bhyve/vga.c
index 208064b..57dc26e 100644
--- a/usr.sbin/bhyve/vga.c
+++ b/usr.sbin/bhyve/vga.c
@@ -161,10 +161,10 @@ struct vga_softc {
 	 */
 	struct {
 		uint8_t		dac_state;
-		int		dac_rd_index;
-		int		dac_rd_subindex;
-		int		dac_wr_index;
-		int		dac_wr_subindex;
+		uint8_t		dac_rd_index;
+		uint8_t		dac_rd_subindex;
+		uint8_t		dac_wr_index;
+		uint8_t		dac_wr_subindex;
 		uint8_t		dac_palette[3 * 256];
 		uint32_t	dac_palette_rgb[256];
 	} vga_dac;