MFC r314319 (by oshogbo):

Don't try to open devices in the gettc() function  which will always
fail in the Capability mode. Instead silently fallback to the syscall
method, which is done for example in the gettimeofday(2) function.

MFC r314320 (by oshogbo):
Remove unneeded variable initialization from r314319.

MFC r321461:
Fix indent.

1 files changed, 25 insertions, 10 deletions

diff --git a/lib/libc/x86/sys/__vdso_gettc.c b/lib/libc/x86/sys/__vdso_gettc.c
index bf46a10..16af7d8 100644
--- a/lib/libc/x86/sys/__vdso_gettc.c
+++ b/lib/libc/x86/sys/__vdso_gettc.c
@@ -33,6 +33,7 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
 #include "namespace.h"
+#include <sys/capsicum.h>
 #include <sys/elf.h>
 #include <sys/fcntl.h>
 #include <sys/mman.h>
@@ -124,6 +125,7 @@ __vdso_init_hpet(uint32_t u)
 	static const char devprefix[] = "/dev/hpet";
 	char devname[64], *c, *c1, t;
 	volatile char *new_map, *old_map;
+	unsigned int mode;
 	uint32_t u1;
 	int fd;
 
@@ -144,18 +146,25 @@ __vdso_init_hpet(uint32_t u)
 	if (old_map != NULL)
 		return;
 
+	if (cap_getmode(&mode) == 0 && mode != 0)
+		goto fail;
+
 	fd = _open(devname, O_RDONLY);
-	if (fd == -1) {
-		atomic_cmpset_rel_ptr((volatile uintptr_t *)&hpet_dev_map[u],
-		    (uintptr_t)old_map, (uintptr_t)MAP_FAILED);
-		return;
-	}
+	if (fd == -1)
+		goto fail;
+
 	new_map = mmap(NULL, PAGE_SIZE, PROT_READ, MAP_SHARED, fd, 0);
 	_close(fd);
 	if (atomic_cmpset_rel_ptr((volatile uintptr_t *)&hpet_dev_map[u],
 	    (uintptr_t)old_map, (uintptr_t)new_map) == 0 &&
 	    new_map != MAP_FAILED)
 		munmap((void *)new_map, PAGE_SIZE);
+
+	return;
+fail:
+	/* Prevent the caller from re-entering. */
+	atomic_cmpset_rel_ptr((volatile uintptr_t *)&hpet_dev_map[u],
+	    (uintptr_t)old_map, (uintptr_t)MAP_FAILED);
 }
 
 #ifdef WANT_HYPERV
@@ -174,16 +183,22 @@ static void
 __vdso_init_hyperv_tsc(void)
 {
 	int fd;
+	unsigned int mode;
+
+	if (cap_getmode(&mode) == 0 && mode != 0)
+		goto fail;
 
 	fd = _open(HYPERV_REFTSC_DEVPATH, O_RDONLY);
-	if (fd < 0) {
-		/* Prevent the caller from re-entering. */
-		hyperv_ref_tsc = MAP_FAILED;
-		return;
-	}
+	if (fd < 0)
+		goto fail;
 	hyperv_ref_tsc = mmap(NULL, sizeof(*hyperv_ref_tsc), PROT_READ,
 	    MAP_SHARED, fd, 0);
 	_close(fd);
+
+	return;
+fail:
+	/* Prevent the caller from re-entering. */
+	hyperv_ref_tsc = MAP_FAILED;
 }
 
 static int