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authorMark Brown <broonie@kernel.org>2016-09-14 18:07:48 +0100
committerMark Brown <broonie@kernel.org>2016-09-14 18:07:48 +0100
commit9fd1cd58356bcc1c4710a454796bff0cc997d5da (patch)
tree0b88d55b02c8969742ee31cf302fd5e284f2f430 /mm/slab.c
parent62bb7104687c0ac1e85b1cf45a85a20b492b06a6 (diff)
parentcfb89f2e7505c6823020a18bbdc5410284305234 (diff)
Merge tag 'asoc-fix-v4.8-rc4' into asoc-arizona
ASoC: Fixes for v4.8 A clutch of fixes for v4.8. These are mainly driver specific, the most notable ones being those for OMAP which fix a series of issues that broke boot on some platforms there when deferred probe kicked in. There's also one core fix for an issue when unbinding a card which for some reason had managed to not manifest until recently.
Diffstat (limited to 'mm/slab.c')
-rw-r--r--mm/slab.c30
1 files changed, 30 insertions, 0 deletions
diff --git a/mm/slab.c b/mm/slab.c
index 261147ba156f..b67271024135 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -4441,6 +4441,36 @@ static int __init slab_proc_init(void)
module_init(slab_proc_init);
#endif
+#ifdef CONFIG_HARDENED_USERCOPY
+/*
+ * Rejects objects that are incorrectly sized.
+ *
+ * Returns NULL if check passes, otherwise const char * to name of cache
+ * to indicate an error.
+ */
+const char *__check_heap_object(const void *ptr, unsigned long n,
+ struct page *page)
+{
+ struct kmem_cache *cachep;
+ unsigned int objnr;
+ unsigned long offset;
+
+ /* Find and validate object. */
+ cachep = page->slab_cache;
+ objnr = obj_to_index(cachep, page, (void *)ptr);
+ BUG_ON(objnr >= cachep->num);
+
+ /* Find offset within object. */
+ offset = ptr - index_to_obj(cachep, page, objnr) - obj_offset(cachep);
+
+ /* Allow address range falling entirely within object size. */
+ if (offset <= cachep->object_size && n <= cachep->object_size - offset)
+ return NULL;
+
+ return cachep->name;
+}
+#endif /* CONFIG_HARDENED_USERCOPY */
+
/**
* ksize - get the actual amount of memory allocated for a given object
* @objp: Pointer to the object