Refactor IMA buffer related functions to make them reusable for carrying TPM logs across kexec.
Signed-off-by: Stefan Berger <stef...@linux.ibm.com> Cc: Rob Herring <robh...@kernel.org> Cc: Frank Rowand <frowand.l...@gmail.com> Cc: Mimi Zohar <zo...@linux.ibm.com> Reviewed-by: Mimi Zohar <zo...@linux.ibm.com> Reviewed-by: Rob Herring <r...@kernel.org> Tested-by: Nageswara R Sastry <rnsas...@linux.ibm.com> Tested-by: Coiby Xu <c...@redhat.com> --- v6: - Add __init to get_kexec_buffer as suggested by Jonathan v5: - Rebased on Jonathan McDowell's commit "b69a2afd5afc x86/kexec: Carry forward IMA measurement log on kexec" v4: - Move debug output into setup_buffer() --- drivers/of/kexec.c | 126 ++++++++++++++++++++++++++------------------- 1 file changed, 74 insertions(+), 52 deletions(-) diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c index 1373d7e0a9b3..fa8c0c75adf9 100644 --- a/drivers/of/kexec.c +++ b/drivers/of/kexec.c @@ -117,45 +117,57 @@ static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr, } #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. - * @size: On successful return, set to the buffer size. - * - * Return: 0 on success, negative errno on error. - */ -int __init ima_get_kexec_buffer(void **addr, size_t *size) +static int __init get_kexec_buffer(const char *name, unsigned long *addr, + size_t *size) { int ret, len; - unsigned long tmp_addr; unsigned long start_pfn, end_pfn; - size_t tmp_size; const void *prop; - prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len); + prop = of_get_property(of_chosen, name, &len); if (!prop) return -ENOENT; - ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size); + ret = do_get_kexec_buffer(prop, len, addr, size); if (ret) return ret; - /* Do some sanity on the returned size for the ima-kexec buffer */ - if (!tmp_size) + /* Do some sanity on the returned size for the kexec buffer */ + if (!*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); + start_pfn = PHYS_PFN(*addr); + end_pfn = PHYS_PFN(*addr + *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); + pr_warn("%s buffer at 0x%lx, size = 0x%zx beyond memory\n", + name, *addr, *size); return -EINVAL; } + return 0; +} + +/** + * ima_get_kexec_buffer - get IMA buffer from the previous kernel + * @addr: On successful return, set to point to the buffer contents. + * @size: On successful return, set to the buffer size. + * + * Return: 0 on success, negative errno on error. + */ +int __init ima_get_kexec_buffer(void **addr, size_t *size) +{ + int ret; + unsigned long tmp_addr; + size_t tmp_size; + + ret = get_kexec_buffer("linux,ima-kexec-buffer", &tmp_addr, &tmp_size); + if (ret) + return ret; + *addr = __va(tmp_addr); *size = tmp_size; @@ -188,72 +200,82 @@ int __init ima_free_kexec_buffer(void) } #endif -/** - * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt - * - * @fdt: Flattened Device Tree to update - * @chosen_node: Offset to the chosen node in the device tree - * - * The IMA measurement buffer is of no use to a subsequent kernel, so we always - * remove it from the device tree. - */ -static void remove_ima_buffer(void *fdt, int chosen_node) +static int remove_buffer(void *fdt, int chosen_node, const char *name) { int ret, len; unsigned long addr; size_t size; const void *prop; - if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC)) - return; - - prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len); + prop = fdt_getprop(fdt, chosen_node, name, &len); if (!prop) - return; + return -ENOENT; ret = do_get_kexec_buffer(prop, len, &addr, &size); - fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer"); + fdt_delprop(fdt, chosen_node, name); if (ret) - return; + return ret; ret = fdt_find_and_del_mem_rsv(fdt, addr, size); if (!ret) - pr_debug("Removed old IMA buffer reservation.\n"); + pr_debug("Remove old %s buffer reserveration", name); + return ret; } -#ifdef CONFIG_IMA_KEXEC /** - * setup_ima_buffer - add IMA buffer information to the fdt - * @image: kexec image being loaded. - * @fdt: Flattened device tree for the next kernel. - * @chosen_node: Offset to the chosen node. + * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt * - * Return: 0 on success, or negative errno on error. + * @fdt: Flattened Device Tree to update + * @chosen_node: Offset to the chosen node in the device tree + * + * The IMA measurement buffer is of no use to a subsequent kernel, so we always + * remove it from the device tree. */ -static int setup_ima_buffer(const struct kimage *image, void *fdt, - int chosen_node) +static void remove_ima_buffer(void *fdt, int chosen_node) +{ + if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC)) + return; + + remove_buffer(fdt, chosen_node, "linux,ima-kexec-buffer"); +} + +#ifdef CONFIG_IMA_KEXEC +static int setup_buffer(void *fdt, int chosen_node, const char *name, + phys_addr_t addr, size_t size) { int ret; - if (!image->ima_buffer_size) + if (!size) return 0; ret = fdt_appendprop_addrrange(fdt, 0, chosen_node, - "linux,ima-kexec-buffer", - image->ima_buffer_addr, - image->ima_buffer_size); + name, addr, size); if (ret < 0) return -EINVAL; - ret = fdt_add_mem_rsv(fdt, image->ima_buffer_addr, - image->ima_buffer_size); + ret = fdt_add_mem_rsv(fdt, addr, size); if (ret) return -EINVAL; - pr_debug("IMA buffer at 0x%pa, size = 0x%zx\n", - &image->ima_buffer_addr, image->ima_buffer_size); + pr_debug("%s at 0x%pa, size = 0x%zx\n", name, &addr, size); return 0; + +} + +/** + * setup_ima_buffer - add IMA buffer information to the fdt + * @image: kexec image being loaded. + * @fdt: Flattened device tree for the next kernel. + * @chosen_node: Offset to the chosen node. + * + * Return: 0 on success, or negative errno on error. + */ +static int setup_ima_buffer(const struct kimage *image, void *fdt, + int chosen_node) +{ + return setup_buffer(fdt, chosen_node, "linux,ima-kexec-buffer", + image->ima_buffer_addr, image->ima_buffer_size); } #else /* CONFIG_IMA_KEXEC */ static inline int setup_ima_buffer(const struct kimage *image, void *fdt, -- 2.38.1 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec