The patch titled
Subject: lib/test_overflow.c: avoid tainting the kernel and fix wrap size
has been added to the -mm tree. Its filename is
lib-test_overflow-avoid-tainting-the-kernel-and-fix-wrap-size.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/lib-test_overflow-avoid-tainting-the-kernel-and-fix-wrap-size.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/lib-test_overflow-avoid-tainting-the-kernel-and-fix-wrap-size.patch
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------------------------------------------------------
From: Kees Cook <keescook@xxxxxxxxxxxx>
Subject: 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 <keescook@xxxxxxxxxxxx>
Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Suggested-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Cc: Joe Perches <joe@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/test_overflow.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
--- a/lib/test_overflow.c~lib-test_overflow-avoid-tainting-the-kernel-and-fix-wrap-size
+++ a/lib/test_overflow.c
@@ -486,16 +486,17 @@ static int __init test_overflow_shift(vo
* 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) \
_
Patches currently in -mm which might be from keescook@xxxxxxxxxxxx are
lib-test_overflow-avoid-tainting-the-kernel-and-fix-wrap-size.patch
