diff options
Diffstat (limited to 'drivers/of/kexec.c')
| -rw-r--r-- | drivers/of/kexec.c | 30 |
1 files changed, 22 insertions, 8 deletions
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c index 8d374cc552be..e6c01db393f9 100644 --- a/drivers/of/kexec.c +++ b/drivers/of/kexec.c @@ -9,6 +9,7 @@ * Copyright (C) 2016 IBM Corporation */ +#include <linux/ima.h> #include <linux/kernel.h> #include <linux/kexec.h> #include <linux/memblock.h> @@ -115,6 +116,7 @@ static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr, return 0; } +#ifdef CONFIG_HAVE_IMA_KEXEC /** * ima_get_kexec_buffer - get IMA buffer from the previous kernel * @addr: On successful return, set to point to the buffer contents. @@ -122,16 +124,14 @@ static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr, * * Return: 0 on success, negative errno on error. */ -int ima_get_kexec_buffer(void **addr, size_t *size) +int __init ima_get_kexec_buffer(void **addr, size_t *size) { int ret, len; unsigned long tmp_addr; + unsigned long start_pfn, end_pfn; size_t tmp_size; const void *prop; - if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC)) - return -ENOTSUPP; - prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len); if (!prop) return -ENOENT; @@ -140,6 +140,22 @@ int ima_get_kexec_buffer(void **addr, size_t *size) if (ret) return ret; + /* Do some sanity on the returned size for the ima-kexec buffer */ + if (!tmp_size) + return -ENOENT; + + /* + * Calculate the PFNs for the buffer and ensure + * they are with in addressable memory. + */ + start_pfn = PHYS_PFN(tmp_addr); + end_pfn = PHYS_PFN(tmp_addr + tmp_size - 1); + if (!page_is_ram(start_pfn) || !page_is_ram(end_pfn)) { + pr_warn("IMA buffer at 0x%lx, size = 0x%zx beyond memory\n", + tmp_addr, tmp_size); + return -EINVAL; + } + *addr = __va(tmp_addr); *size = tmp_size; @@ -149,16 +165,13 @@ int ima_get_kexec_buffer(void **addr, size_t *size) /** * ima_free_kexec_buffer - free memory used by the IMA buffer */ -int ima_free_kexec_buffer(void) +int __init ima_free_kexec_buffer(void) { int ret; unsigned long addr; size_t size; struct property *prop; - if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC)) - return -ENOTSUPP; - prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL); if (!prop) return -ENOENT; @@ -173,6 +186,7 @@ int ima_free_kexec_buffer(void) return memblock_phys_free(addr, size); } +#endif /** * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt |