Commit d132443a authored May 19, 2020 by Christophe Leroy Committed by Michael Ellerman May 20, 2020

powerpc/kasan: Fix error detection on memory allocation



In case (k_start & PAGE_MASK) doesn't equal (kstart), 'va' will never be
NULL allthough 'block' is NULL

Check the return of memblock_alloc() directly instead of
the resulting address in the loop.

Fixes: 509cd3f2 ("powerpc/32: Simplify KASAN init")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7cb8ca82042bfc45a5cfe726c921cd7e7eeb12a3.1589866984.git.christophe.leroy@csgroup.eu

parent 30df74d6

arch/powerpc/mm/kasan/kasan_init_32.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -76,15 +76,14 @@ static int __init kasan_init_region(void *start, size_t size)
		return ret;

		block = memblock_alloc(k_end - k_start, PAGE_SIZE);
		if (!block)
		return -ENOMEM;

		for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) {
		pmd_t *pmd = pmd_ptr_k(k_cur);
		void *va = block + k_cur - k_start;
		pte_t pte = pfn_pte(PHYS_PFN(__pa(va)), PAGE_KERNEL);

		if (!va)
		return -ENOMEM;

		__set_pte_at(&init_mm, k_cur, pte_offset_kernel(pmd, k_cur), pte, 0);
		}
		flush_tlb_kernel_range(k_start, k_end);

Admin message