4.7-stable review patch. If anyone has any objections, please let me know.
------------------ From: Austin Christ <[email protected]> commit 6862e6ad95e984991a6ceec592cf67831658f928 upstream. According to UEFI 2.6 section 7.5.3, the capsule should be in contiguous virtual memory and firmware may consume the capsule immediately. To correctly implement this functionality, the kernel driver needs to vmap the entire capsule at the time it is made available to firmware. The virtual allocation of the capsule update has been changed from kmap, which was only allocating the first page of the update, to vmap, and allocates the entire data payload. Signed-off-by: Austin Christ <[email protected]> Signed-off-by: Matt Fleming <[email protected]> Reviewed-by: Matt Fleming <[email protected]> Reviewed-by: Lee, Chun-Yi <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Bryan O'Donoghue <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Kweh Hock Leong <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/firmware/efi/capsule-loader.c | 8 +++++--- drivers/firmware/efi/capsule.c | 6 +++--- 2 files changed, 8 insertions(+), 6 deletions(-) --- a/drivers/firmware/efi/capsule-loader.c +++ b/drivers/firmware/efi/capsule-loader.c @@ -16,6 +16,7 @@ #include <linux/slab.h> #include <linux/mutex.h> #include <linux/efi.h> +#include <linux/vmalloc.h> #define NO_FURTHER_WRITE_ACTION -1 @@ -108,14 +109,15 @@ static ssize_t efi_capsule_submit_update int ret; void *cap_hdr_temp; - cap_hdr_temp = kmap(cap_info->pages[0]); + cap_hdr_temp = vmap(cap_info->pages, cap_info->index, + VM_MAP, PAGE_KERNEL); if (!cap_hdr_temp) { - pr_debug("%s: kmap() failed\n", __func__); + pr_debug("%s: vmap() failed\n", __func__); return -EFAULT; } ret = efi_capsule_update(cap_hdr_temp, cap_info->pages); - kunmap(cap_info->pages[0]); + vunmap(cap_hdr_temp); if (ret) { pr_err("%s: efi_capsule_update() failed\n", __func__); return ret; --- a/drivers/firmware/efi/capsule.c +++ b/drivers/firmware/efi/capsule.c @@ -190,9 +190,9 @@ efi_capsule_update_locked(efi_capsule_he * map the capsule described by @capsule with its data in @pages and * send it to the firmware via the UpdateCapsule() runtime service. * - * @capsule must be a virtual mapping of the first page in @pages - * (@pages[0]) in the kernel address space. That is, a - * capsule_header_t that describes the entire contents of the capsule + * @capsule must be a virtual mapping of the complete capsule update in the + * kernel address space, as the capsule can be consumed immediately. + * A capsule_header_t that describes the entire contents of the capsule * must be at the start of the first data page. * * Even though this function will validate that the firmware supports
