[Cc'ing Borislav Petkov <bp@xxxxxxx>, Jonathan McDowell <noodles@xxxxxx >] Hi Stefan, On Thu, 2022-06-30 at 22:26 -0400, Stefan Berger wrote: > Refactor IMA buffer related functions to make them reusable for carrying > TPM logs across kexec. > > Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx> > Cc: Rob Herring <robh+dt@xxxxxxxxxx> > Cc: Frank Rowand <frowand.list@xxxxxxxxx> > Cc: Mimi Zohar <zohar@xxxxxxxxxxxxx> Refactoring the ima_get_kexec_buffer sounds good, but there's a merge conflict with Jonathan McDowell's commit "b69a2afd5afc x86/kexec: Carry forward IMA measurement log on kexec". https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/of/kexec.c thanks, Mimi > > --- > v4: > - Move debug output into setup_buffer() > --- > drivers/of/kexec.c | 131 ++++++++++++++++++++++++++------------------- > 1 file changed, 76 insertions(+), 55 deletions(-) > > diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c > index c4f9b6655a2e..0710703acfb0 100644 > --- a/drivers/of/kexec.c > +++ b/drivers/of/kexec.c > @@ -115,48 +115,59 @@ static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr, > 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 ima_get_kexec_buffer(void **addr, size_t *size) > +static int 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; > > - if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC)) > - return -ENOTSUPP; > - > - 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 ima_get_kexec_buffer(void **addr, size_t *size) > +{ > + int ret; > + unsigned long tmp_addr; > + size_t tmp_size; > + > + if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC)) > + return -ENOTSUPP; > + > + ret = get_kexec_buffer("linux,ima-kexec-buffer", &tmp_addr, &tmp_size); > + if (ret) > + return ret; > + > *addr = __va(tmp_addr); > *size = tmp_size; > > @@ -191,72 +202,82 @@ int ima_free_kexec_buffer(void) > return memblock_phys_free(addr, size); > } > > -/** > - * 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,
