On Tue, Jul 05, 2022 at 06:46:54PM -0400, Mimi Zohar wrote: > [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 None of this looks difficult to re-do on top of my changes that are in -next; the only thing to watch out for is a couple of functions have moved into the __init section but that looks appropriate for your TPM log carry-over too. > > --- > > 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,
