diff options
Diffstat (limited to 'PCI-Lock-down-BAR-access-when-module-security-is-ena.patch')
| -rw-r--r-- | PCI-Lock-down-BAR-access-when-module-security-is-ena.patch | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/PCI-Lock-down-BAR-access-when-module-security-is-ena.patch b/PCI-Lock-down-BAR-access-when-module-security-is-ena.patch new file mode 100644 index 000000000..92e028d07 --- /dev/null +++ b/PCI-Lock-down-BAR-access-when-module-security-is-ena.patch @@ -0,0 +1,113 @@ +From: Matthew Garrett <matthew.garrett@nebula.com> +Date: Thu, 8 Mar 2012 10:10:38 -0500 +Subject: [PATCH] PCI: Lock down BAR access when module security is enabled + +Any hardware that can potentially generate DMA has to be locked down from +userspace 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: Matthew Garrett <matthew.garrett@nebula.com> +--- + drivers/pci/pci-sysfs.c | 10 ++++++++++ + drivers/pci/proc.c | 8 +++++++- + drivers/pci/syscall.c | 3 ++- + 3 files changed, 19 insertions(+), 2 deletions(-) + +diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c +index 312f23a8429c..93e6ac103dd0 100644 +--- a/drivers/pci/pci-sysfs.c ++++ b/drivers/pci/pci-sysfs.c +@@ -30,6 +30,7 @@ + #include <linux/vgaarb.h> + #include <linux/pm_runtime.h> + #include <linux/of.h> ++#include <linux/module.h> + #include "pci.h" + + static int sysfs_initialized; /* = 0 */ +@@ -710,6 +711,9 @@ static ssize_t pci_write_config(struct file *filp, struct kobject *kobj, + loff_t init_off = off; + u8 *data = (u8 *) buf; + ++ if (secure_modules()) ++ return -EPERM; ++ + if (off > dev->cfg_size) + return 0; + if (off + count > dev->cfg_size) { +@@ -1004,6 +1008,9 @@ static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr, + resource_size_t start, end; + int i; + ++ if (secure_modules()) ++ return -EPERM; ++ + for (i = 0; i < PCI_ROM_RESOURCE; i++) + if (res == &pdev->resource[i]) + break; +@@ -1105,6 +1112,9 @@ static ssize_t pci_write_resource_io(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, char *buf, + loff_t off, size_t count) + { ++ if (secure_modules()) ++ return -EPERM; ++ + return pci_resource_io(filp, kobj, attr, buf, off, count, true); + } + +diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c +index 3f155e78513f..4265ea07e3b0 100644 +--- a/drivers/pci/proc.c ++++ b/drivers/pci/proc.c +@@ -116,6 +116,9 @@ static ssize_t proc_bus_pci_write(struct file *file, const char __user *buf, + int size = dev->cfg_size; + int cnt; + ++ if (secure_modules()) ++ return -EPERM; ++ + if (pos >= size) + return 0; + if (nbytes >= size) +@@ -195,6 +198,9 @@ static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd, + #endif /* HAVE_PCI_MMAP */ + int ret = 0; + ++ if (secure_modules()) ++ return -EPERM; ++ + switch (cmd) { + case PCIIOC_CONTROLLER: + ret = pci_domain_nr(dev->bus); +@@ -233,7 +239,7 @@ static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma) + struct pci_filp_private *fpriv = file->private_data; + int i, ret; + +- if (!capable(CAP_SYS_RAWIO)) ++ if (!capable(CAP_SYS_RAWIO) || secure_modules()) + return -EPERM; + + /* Make sure the caller is mapping a real resource for this device */ +diff --git a/drivers/pci/syscall.c b/drivers/pci/syscall.c +index b91c4da68365..98f5637304d1 100644 +--- a/drivers/pci/syscall.c ++++ b/drivers/pci/syscall.c +@@ -10,6 +10,7 @@ + #include <linux/errno.h> + #include <linux/pci.h> + #include <linux/syscalls.h> ++#include <linux/module.h> + #include <asm/uaccess.h> + #include "pci.h" + +@@ -92,7 +93,7 @@ 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) || secure_modules()) + return -EPERM; + + dev = pci_get_bus_and_slot(bus, dfn); |