efi/capsule: Remove NULL test on kmap()

kmap() can't fail.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Kweh Hock Leong <hock.leong.kweh@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170602135207.21708-8-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

drivers/firmware/efi/capsule-loader.c

@@ -170,10 +170,6 @@ static ssize_t efi_capsule_write(struct file *file, const char __user *buff,
 	page = cap_info->pages[cap_info->index - 1];
 
 	kbuff = kmap(page);
-	if (!kbuff) {
-		ret = -ENOMEM;
-		goto failed;
-	}
 	kbuff += PAGE_SIZE - cap_info->page_bytes_remain;
 
 	/* Copy capsule binary data from user space to kernel space buffer */

drivers/firmware/efi/capsule.c

@@ -247,10 +247,6 @@ int efi_capsule_update(efi_capsule_header_t *capsule, struct page **pages)
 		efi_capsule_block_desc_t *sglist;
 
 		sglist = kmap(sg_pages[i]);
-		if (!sglist) {
-			rv = -ENOMEM;
-			goto out;
-		}
 
 		for (j = 0; j < SGLIST_PER_PAGE && count > 0; j++) {
 			u64 sz = min_t(u64, imagesize, PAGE_SIZE);