diff options
| author | Matthew Garrett <mjg59@srcf.ucam.org> | 2019-08-19 17:17:47 -0700 |
|---|---|---|
| committer | James Morris <jmorris@namei.org> | 2019-08-19 21:54:15 -0700 |
| commit | eb627e17727ebeede70697ae1798688b0d328b54 (patch) | |
| tree | 9551483d5fd043ebee8c15e1e580d7587aa070ee /drivers/pci/syscall.c | |
| parent | 38bd94b8a1bd46e6d3d9718c7ff582e4c8ccb440 (diff) | |
| download | linux-eb627e17727ebeede70697ae1798688b0d328b54.tar.bz2 | |
PCI: Lock down BAR access when the kernel is locked down
Any hardware that can potentially generate DMA has to be locked down in
order to avoid it being possible for an attacker to modify kernel code,
allowing them to circumvent disabled module loading or module signing.
Default to paranoid - in future we can potentially relax this for
sufficiently IOMMU-isolated devices.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: linux-pci@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'drivers/pci/syscall.c')
| -rw-r--r-- | drivers/pci/syscall.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/pci/syscall.c b/drivers/pci/syscall.c index d96626c614f5..31e39558d49d 100644 --- a/drivers/pci/syscall.c +++ b/drivers/pci/syscall.c @@ -7,6 +7,7 @@ #include <linux/errno.h> #include <linux/pci.h> +#include <linux/security.h> #include <linux/syscalls.h> #include <linux/uaccess.h> #include "pci.h" @@ -90,7 +91,8 @@ SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn, u32 dword; int err = 0; - if (!capable(CAP_SYS_ADMIN)) + if (!capable(CAP_SYS_ADMIN) || + security_locked_down(LOCKDOWN_PCI_ACCESS)) return -EPERM; dev = pci_get_domain_bus_and_slot(0, bus, dfn); |