From d132443a73d7a131775df46f33000f67ed92de1e Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 19 May 2020 05:48:43 +0000 Subject: [PATCH] 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: 509cd3f2b473 ("powerpc/32: Simplify KASAN init") Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/7cb8ca82042bfc45a5cfe726c921cd7e7eeb12a3.1589866984.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/kasan/kasan_init_32.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c index cbcad36..8b15fe0 100644 --- a/arch/powerpc/mm/kasan/kasan_init_32.c +++ b/arch/powerpc/mm/kasan/kasan_init_32.c @@ -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); -- 2.7.4