[PATCH 05/10] mm, util: Use dup_user to duplicate user memory
From: Ezequiel Garcia <hidden>
Date: 2012-09-08 20:50:16
Also in:
lkml
Subsystem:
memory management, memory management - core, the rest · Maintainers:
Andrew Morton, David Hildenbrand, Linus Torvalds
Previously the strndup_user allocation was being done through memdup_user, and the caller was wrongly traced as being strndup_user (the correct trace must report the caller of strndup_user). This is a common problem: in order to get accurate callsite tracing, a utils function can't allocate through another utils function, but instead do the allocation himself (or inlined). Here we fix this by creating an always inlined dup_user() function to performed the real allocation and to be used by memdup_user and strndup_user. Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Ezequiel Garcia <redacted> --- mm/util.c | 11 ++++++++--- 1 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/mm/util.c b/mm/util.c
index dc3036c..48d3ff8b 100644
--- a/mm/util.c
+++ b/mm/util.c@@ -76,14 +76,14 @@ void *kmemdup(const void *src, size_t len, gfp_t gfp) EXPORT_SYMBOL(kmemdup); /** - * memdup_user - duplicate memory region from user space + * dup_user - duplicate memory region from user space * * @src: source address in user space * @len: number of bytes to copy * * Returns an ERR_PTR() on failure. */ -void *memdup_user(const void __user *src, size_t len) +static __always_inline void *dup_user(const void __user *src, size_t len) { void *p;
@@ -103,6 +103,11 @@ void *memdup_user(const void __user *src, size_t len) return p; } + +void *memdup_user(const void __user *src, size_t len) +{ + return dup_user(src, len); +} EXPORT_SYMBOL(memdup_user); static __always_inline void *__do_krealloc(const void *p, size_t new_size,
@@ -214,7 +219,7 @@ char *strndup_user(const char __user *s, long n) if (length > n) return ERR_PTR(-EINVAL); - p = memdup_user(s, length); + p = dup_user(s, length); if (IS_ERR(p)) return p;
--
1.7.8.6
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