diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c
index dc73bc54cc4e..d9da7e148538 100644
--- a/Documentation/lguest/lguest.c
+++ b/Documentation/lguest/lguest.c
@@ -39,6 +39,9 @@
#include <limits.h>
#include <stddef.h>
#include <signal.h>
+#include <pwd.h>
+#include <grp.h>
+
#include <linux/virtio_config.h>
#include <linux/virtio_net.h>
#include <linux/virtio_blk.h>
@@ -298,20 +301,27 @@ static void *map_zeroed_pages(unsigned int num)
/*
* We use a private mapping (ie. if we write to the page, it will be
- * copied).
+ * copied). We allocate an extra two pages PROT_NONE to act as guard
+ * pages against read/write attempts that exceed allocated space.
*/
- addr = mmap(NULL, getpagesize() * num,
- PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, fd, 0);
+ addr = mmap(NULL, getpagesize() * (num+2),
+ PROT_NONE, MAP_PRIVATE, fd, 0);
+
if (addr == MAP_FAILED)
err(1, "Mmapping %u pages of /dev/zero", num);
+ if (mprotect(addr + getpagesize(), getpagesize() * num,
+ PROT_READ|PROT_WRITE) == -1)
+ err(1, "mprotect rw %u pages failed", num);
+
/*
* One neat mmap feature is that you can close the fd, and it
* stays mapped.
*/
close(fd);
- return addr;
+ /* Return address after PROT_NONE page */
+ return addr + getpagesize();
}
/* Get some more pages for a device. */
@@ -343,7 +353,7 @@ static void map_at(int fd, void *addr, unsigned long offset, unsigned long len)
* done to it. This allows us to share untouched memory between
* Guests.
*/
- if (mmap(addr, len, PROT_READ|PROT_WRITE|PROT_EXEC,
+ if (mmap(addr, len, PROT_READ|PROT_WRITE,
MAP_FIXED|MAP_PRIVATE, fd, offset) != MAP_FAILED)
return;
@@ -573,10 +583,10 @@ static void *_check_pointer(unsigned long addr, unsigned int size,
unsigned int line)
{
/*
- * We have to separately check addr and addr+size, because size could
- * be huge and addr + size might wrap around.
+ * Check if the requested address and size exceeds the allocated memory,
+ * or addr + size wraps around.
*/
- if (addr >= guest_limit || addr + size >= guest_limit)
+ if ((addr + size) > guest_limit || (addr + size) < addr)
errx(1, "%s:%i: Invalid address %#lx", __FILE__, line, addr);
/*
* We return a pointer for the caller's convenience, now we know it's
@@ -1872,6 +1882,8 @@ static struct option opts[] = {
{ "block", 1, NULL, 'b' },
{ "rng", 0, NULL, 'r' },
{ "initrd", 1, NULL, 'i' },
+ { "username", 1, NULL, 'u' },
+ { "chroot", 1, NULL, 'c' },
{ NULL },
};
static void usage(void)
@@ -1894,6 +1906,12 @@ int main(int argc, char *argv[])
/* If they specify an initrd file to load. */
const char *initrd_name = NULL;
+ /* Password structure for initgroups/setres[gu]id */
+ struct passwd *user_details = NULL;
+
+ /* Directory to chroot to */
+ char *chroot_path = NULL;
+
/* Save the args: we "reboot" by execing ourselves again. */
main_args = argv;
@@ -1950,6 +1968,14 @@ int main(int argc, char *argv[])
case 'i':
initrd_name = optarg;
break;
+ case 'u':
+ user_details = getpwnam(optarg);
+ if (!user_details)
+ err(1, "getpwnam failed, incorrect username?");
+ break;
+ case 'c':
+ chroot_path = optarg;
+ break;
default:
warnx("Unknown argument %s", argv[optind]);
usage();
@@ -2021,6 +2047,37 @@ int main(int argc, char *argv[])
/* If we exit via err(), this kills all the threads, restores tty. */
atexit(cleanup_devices);
+ /* If requested, chroot to a directory */
+ if (chroot_path) {
+ if (chroot(chroot_path) != 0)
+ err(1, "chroot(\"%s\") failed", chroot_path);
+
+ if (chdir("/") != 0)
+ err(1, "chdir(\"/\") failed");
+
+ verbose("chroot done\n");
+ }
+
+ /* If requested, drop privileges */
+ if (user_details) {
+ uid_t u;
+ gid_t g;
+
+ u = user_details->pw_uid;
+ g = user_details->pw_gid;
+
+ if (initgroups(user_details->pw_name, g) != 0)
+ err(1, "initgroups failed");
+
+ if (setresgid(g, g, g) != 0)
+ err(1, "setresgid failed");
+
+ if (setresuid(u, u, u) != 0)
+ err(1, "setresuid failed");
+
+ verbose("Dropping privileges completed\n");
+ }
+
/* Finally, run the Guest. This doesn't return. */
run_guest();
}
diff --git a/Documentation/lguest/lguest.txt b/Documentation/lguest/lguest.txt
index 6ccaf8e1a00e..dad99978a6a8 100644
--- a/Documentation/lguest/lguest.txt
+++ b/Documentation/lguest/lguest.txt
@@ -117,6 +117,11 @@ Running Lguest:
for general information on how to get bridging to work.
+- Random number generation. Using the --rng option will provide a
+ /dev/hwrng in the guest that will read from the host's /dev/random.
+ Use this option in conjunction with rng-tools (see ../hw_random.txt)
+ to provide entropy to the guest kernel's /dev/random.
+
There is a helpful mailing list at http://ozlabs.org/mailman/listinfo/lguest
Good luck!
diff --git a/arch/x86/lguest/Kconfig b/arch/x86/lguest/Kconfig
index 38718041efc3..6e121a2a49e1 100644
--- a/arch/x86/lguest/Kconfig
+++ b/arch/x86/lguest/Kconfig
@@ -2,6 +2,7 @@ config LGUEST_GUEST
bool "Lguest guest support"
select PARAVIRT
depends on X86_32
+ select VIRTUALIZATION
select VIRTIO
select VIRTIO_RING
select VIRTIO_CONSOLE
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 4996cf5f73a0..eba687f0cc0c 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -824,7 +824,7 @@ static void __init lguest_init_IRQ(void)
for (i = FIRST_EXTERNAL_VECTOR; i < NR_VECTORS; i++) {
/* Some systems map "vectors" to interrupts weirdly. Not us! */
- __get_cpu_var(vector_irq)[i] = i - FIRST_EXTERNAL_VECTOR;
+ __this_cpu_write(vector_irq[i], i - FIRST_EXTERNAL_VECTOR);
if (i != SYSCALL_VECTOR)
set_intr_gate(i, interrupt[i - FIRST_EXTERNAL_VECTOR]);
}
diff --git a/drivers/lguest/page_tables.c b/drivers/lguest/page_tables.c
index 04b22128a474..d21578ee95de 100644
--- a/drivers/lguest/page_tables.c
+++ b/drivers/lguest/page_tables.c
@@ -1137,7 +1137,7 @@ void free_guest_pagetable(struct lguest *lg)
*/
void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages)
{
- pte_t *switcher_pte_page = __get_cpu_var(switcher_pte_pages);
+ pte_t *switcher_pte_page = __this_cpu_read(switcher_pte_pages);
pte_t regs_pte;
#ifdef CONFIG_X86_PAE
diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c
index b4eb675a807e..9f1659c3d1f3 100644
--- a/drivers/lguest/x86/core.c
+++ b/drivers/lguest/x86/core.c
@@ -90,8 +90,8 @@ static void copy_in_guest_info(struct lg_cpu *cpu, struct lguest_pages *pages)
* meanwhile). If that's not the case, we pretend everything in the
* Guest has changed.
*/
- if (__get_cpu_var(lg_last_cpu) != cpu || cpu->last_pages != pages) {
- __get_cpu_var(lg_last_cpu) = cpu;
+ if (__this_cpu_read(lg_last_cpu) != cpu || cpu->last_pages != pages) {
+ __this_cpu_write(lg_last_cpu, cpu);
cpu->last_pages = pages;
cpu->changed = CHANGED_ALL;
}
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index ef8d9d558fc7..4fb5b2bf2348 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -96,11 +96,6 @@ static struct pci_device_id virtio_pci_id_table[] = {
MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);
-/* A PCI device has it's own struct device and so does a virtio device so
- * we create a place for the virtio devices to show up in sysfs. I think it
- * would make more sense for virtio to not insist on having it's own device. */
-static struct device *virtio_pci_root;
-
/* Convert a generic virtio device to our structure */
static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
{
@@ -629,7 +624,7 @@ static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
if (vp_dev == NULL)
return -ENOMEM;
- vp_dev->vdev.dev.parent = virtio_pci_root;
+ vp_dev->vdev.dev.parent = &pci_dev->dev;
vp_dev->vdev.dev.release = virtio_pci_release_dev;
vp_dev->vdev.config = &virtio_pci_config_ops;
vp_dev->pci_dev = pci_dev;
@@ -717,17 +712,7 @@ static struct pci_driver virtio_pci_driver = {
static int __init virtio_pci_init(void)
{
- int err;
-
- virtio_pci_root = root_device_register("virtio-pci");
- if (IS_ERR(virtio_pci_root))
- return PTR_ERR(virtio_pci_root);
-
- err = pci_register_driver(&virtio_pci_driver);
- if (err)
- root_device_unregister(virtio_pci_root);
-
- return err;
+ return pci_register_driver(&virtio_pci_driver);
}
module_init(virtio_pci_init);
@@ -735,7 +720,6 @@ module_init(virtio_pci_init);
static void __exit virtio_pci_exit(void)
{
pci_unregister_driver(&virtio_pci_driver);
- root_device_unregister(virtio_pci_root);
}
module_exit(virtio_pci_exit);