diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-firmware-gsmi | 2 | ||||
| -rw-r--r-- | drivers/firmware/google/coreboot_table.c | 43 |
2 files changed, 37 insertions, 8 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-gsmi b/Documentation/ABI/testing/sysfs-firmware-gsmi index 7a558354c1ee..3b3c3ae6f458 100644 --- a/Documentation/ABI/testing/sysfs-firmware-gsmi +++ b/Documentation/ABI/testing/sysfs-firmware-gsmi @@ -19,7 +19,7 @@ Description: /sys/firmware/gsmi/vars: This directory has the same layout (and - underlying implementation as /sys/firmware/efi/vars. + underlying implementation) as /sys/firmware/efi/vars. See `Documentation/ABI/*/sysfs-firmware-efi-vars` for more information on how to interact with this structure. diff --git a/drivers/firmware/google/coreboot_table.c b/drivers/firmware/google/coreboot_table.c index e63933ff6747..25ee8cf53429 100644 --- a/drivers/firmware/google/coreboot_table.c +++ b/drivers/firmware/google/coreboot_table.c @@ -13,8 +13,10 @@ #include <linux/err.h> #include <linux/init.h> #include <linux/io.h> +#include <linux/ioport.h> #include <linux/kernel.h> #include <linux/device-id/coreboot.h> +#include <linux/mm.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> @@ -123,7 +125,7 @@ static int coreboot_table_populate(struct device *dev, void *ptr, resource_size_ ptr_end = ptr + len; ptr_entry = ptr + header->header_bytes; - for (i = 0; i < header->table_entries; i++) { + for (i = 0; i < header->table_entries; i++, ptr_entry += entry->size) { if (ptr_entry + sizeof(*entry) > ptr_end) return -EINVAL; entry = ptr_entry; @@ -147,6 +149,26 @@ static int coreboot_table_populate(struct device *dev, void *ptr, resource_size_ switch (device->entry.tag) { case LB_TAG_CBMEM_ENTRY: + /* + * Skip entries that are not exclusively System RAM or + * Reserved memory. + * On ARM64, no-map regions are filtered out as they are + * IORESOURCE_MEM (see request_standard_resources() in + * arch/arm64/kernel/setup.c). + * On x86, CBMEM often resides in standard reserved regions + * (IORES_DESC_RESERVED). + */ + if (region_intersects(device->cbmem_entry.address, + device->cbmem_entry.entry_size, + IORESOURCE_SYSTEM_RAM, + IORES_DESC_NONE) != REGION_INTERSECTS && + region_intersects(device->cbmem_entry.address, + device->cbmem_entry.entry_size, + IORESOURCE_MEM, + IORES_DESC_RESERVED) != REGION_INTERSECTS) { + kfree(device); + continue; + } dev_set_name(&device->dev, "cbmem-%08x", device->cbmem_entry.id); break; @@ -155,8 +177,6 @@ static int coreboot_table_populate(struct device *dev, void *ptr, resource_size_ break; } - ptr_entry += entry->size; - ret = device_register(&device->dev); if (ret) { dev_warn(dev, "failed to register coreboot device: %d\n", ret); @@ -170,6 +190,7 @@ static int coreboot_table_populate(struct device *dev, void *ptr, resource_size_ static int coreboot_table_probe(struct platform_device *pdev) { resource_size_t len; + resource_size_t table_span; struct coreboot_table_header *header; struct resource *res; struct device *dev = &pdev->dev; @@ -181,7 +202,7 @@ static int coreboot_table_probe(struct platform_device *pdev) return -EINVAL; len = resource_size(res); - if (!res->start || !len) + if (!res->start || len < sizeof(*header)) return -EINVAL; /* Check just the header first to make sure things are sane */ @@ -189,19 +210,27 @@ static int coreboot_table_probe(struct platform_device *pdev) if (!header) return -ENOMEM; - len = header->header_bytes + header->table_bytes; ret = strncmp(header->signature, "LBIO", sizeof(header->signature)); + + if (!ret && + (header->header_bytes < sizeof(*header) || + check_add_overflow((resource_size_t)header->header_bytes, + (resource_size_t)header->table_bytes, + &table_span) || + table_span > len)) + ret = -EINVAL; + memunmap(header); if (ret) { dev_warn(dev, "coreboot table missing or corrupt!\n"); return -ENODEV; } - ptr = memremap(res->start, len, MEMREMAP_WB); + ptr = memremap(res->start, table_span, MEMREMAP_WB); if (!ptr) return -ENOMEM; - ret = coreboot_table_populate(dev, ptr, len); + ret = coreboot_table_populate(dev, ptr, table_span); memunmap(ptr); |