From 8e060c21ae2c265a2b596e9e7f9f97ec274151a4 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 16 Jul 2019 16:27:24 -0700 Subject: [PATCH] lib/test_overflow.c: avoid tainting the kernel and fix wrap size This adds __GFP_NOWARN to the kmalloc()-portions of the overflow test to avoid tainting the kernel. Additionally fixes up the math on wrap size to be architecture and page size agnostic. Link: http://lkml.kernel.org/r/201905282012.0A8767E24@keescook Fixes: ca90800a91ba ("test_overflow: Add memory allocation overflow tests") Signed-off-by: Kees Cook Reported-by: Randy Dunlap Suggested-by: Rasmus Villemoes Cc: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/test_overflow.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/lib/test_overflow.c b/lib/test_overflow.c index fc68056..7a4b6f6 100644 --- a/lib/test_overflow.c +++ b/lib/test_overflow.c @@ -486,16 +486,17 @@ static int __init test_overflow_shift(void) * Deal with the various forms of allocator arguments. See comments above * the DEFINE_TEST_ALLOC() instances for mapping of the "bits". */ -#define alloc010(alloc, arg, sz) alloc(sz, GFP_KERNEL) -#define alloc011(alloc, arg, sz) alloc(sz, GFP_KERNEL, NUMA_NO_NODE) +#define alloc_GFP (GFP_KERNEL | __GFP_NOWARN) +#define alloc010(alloc, arg, sz) alloc(sz, alloc_GFP) +#define alloc011(alloc, arg, sz) alloc(sz, alloc_GFP, NUMA_NO_NODE) #define alloc000(alloc, arg, sz) alloc(sz) #define alloc001(alloc, arg, sz) alloc(sz, NUMA_NO_NODE) -#define alloc110(alloc, arg, sz) alloc(arg, sz, GFP_KERNEL) +#define alloc110(alloc, arg, sz) alloc(arg, sz, alloc_GFP) #define free0(free, arg, ptr) free(ptr) #define free1(free, arg, ptr) free(arg, ptr) -/* Wrap around to 8K */ -#define TEST_SIZE (9 << PAGE_SHIFT) +/* Wrap around to 16K */ +#define TEST_SIZE (5 * 4096) #define DEFINE_TEST_ALLOC(func, free_func, want_arg, want_gfp, want_node)\ static int __init test_ ## func (void *arg) \ -- 2.7.4