The patch titled
Subject: mm: new primitive kvmemdup()
has been added to the -mm mm-unstable branch. Its filename is
mm-new-primitive-kvmemdup.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-new-primitive-kvmemdup.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
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------------------------------------------------------
From: Hao Sun <sunhao.th@xxxxxxxxx>
Subject: mm: new primitive kvmemdup()
Date: Wed, 21 Dec 2022 22:42:45 +0800
Similar to kmemdup(), but support large amount of bytes with kvmalloc()
and does *not* guarantee that the result will be physically contiguous.
Use only in cases where kvmalloc() is needed and free it with kvfree().
Also adapt policy_unpack.c in case someone bisect into this.
Link: https://lkml.kernel.org/r/20221221144245.27164-1-sunhao.th@xxxxxxxxx
Signed-off-by: Hao Sun <sunhao.th@xxxxxxxxx>
Suggested-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: Nick Terrell <terrelln@xxxxxx>
Cc: John Johansen <john.johansen@xxxxxxxxxxxxx>
Cc: Paul Moore <paul@xxxxxxxxxxxxxx>
Cc: James Morris <jmorris@xxxxxxxxx>
Cc: "Serge E. Hallyn" <serge@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/string.h | 1 +
mm/util.c | 24 +++++++++++++++++++++++-
security/apparmor/policy_unpack.c | 11 +----------
3 files changed, 25 insertions(+), 11 deletions(-)
--- a/include/linux/string.h~mm-new-primitive-kvmemdup
+++ a/include/linux/string.h
@@ -177,6 +177,7 @@ extern char *kstrdup(const char *s, gfp_
extern const char *kstrdup_const(const char *s, gfp_t gfp);
extern char *kstrndup(const char *s, size_t len, gfp_t gfp);
extern void *kmemdup(const void *src, size_t len, gfp_t gfp) __realloc_size(2);
+extern void *kvmemdup(const void *src, size_t len, gfp_t gfp) __realloc_size(2);
extern char *kmemdup_nul(const char *s, size_t len, gfp_t gfp);
extern char **argv_split(gfp_t gfp, const char *str, int *argcp);
--- a/mm/util.c~mm-new-primitive-kvmemdup
+++ a/mm/util.c
@@ -120,7 +120,8 @@ EXPORT_SYMBOL(kstrndup);
* @len: memory region length
* @gfp: GFP mask to use
*
- * Return: newly allocated copy of @src or %NULL in case of error
+ * Return: newly allocated copy of @src or %NULL in case of error,
+ * result is physically contiguous. Use kfree() to free.
*/
void *kmemdup(const void *src, size_t len, gfp_t gfp)
{
@@ -134,6 +135,27 @@ void *kmemdup(const void *src, size_t le
EXPORT_SYMBOL(kmemdup);
/**
+ * kvmemdup - duplicate region of memory
+ *
+ * @src: memory region to duplicate
+ * @len: memory region length
+ * @gfp: GFP mask to use
+ *
+ * Return: newly allocated copy of @src or %NULL in case of error,
+ * result may be not physically contiguous. Use kvfree() to free.
+ */
+void *kvmemdup(const void *src, size_t len, gfp_t gfp)
+{
+ void *p;
+
+ p = kvmalloc(len, gfp);
+ if (p)
+ memcpy(p, src, len);
+ return p;
+}
+EXPORT_SYMBOL(kvmemdup);
+
+/**
* kmemdup_nul - Create a NUL-terminated string from unterminated data
* @s: The data to stringify
* @len: The size of the data
--- a/security/apparmor/policy_unpack.c~mm-new-primitive-kvmemdup
+++ a/security/apparmor/policy_unpack.c
@@ -161,15 +161,6 @@ VISIBLE_IF_KUNIT bool aa_inbounds(struct
}
EXPORT_SYMBOL_IF_KUNIT(aa_inbounds);
-static void *kvmemdup(const void *src, size_t len)
-{
- void *p = kvmalloc(len, GFP_KERNEL);
-
- if (p)
- memcpy(p, src, len);
- return p;
-}
-
/**
* aa_unpack_u16_chunk - test and do bounds checking for a u16 size based chunk
* @e: serialized data read head (NOT NULL)
@@ -1027,7 +1018,7 @@ static struct aa_profile *unpack_profile
data->key = key;
data->size = aa_unpack_blob(e, &data->data, NULL);
- data->data = kvmemdup(data->data, data->size);
+ data->data = kvmemdup(data->data, data->size, GFP_KERNEL);
if (data->size && !data->data) {
kfree_sensitive(data->key);
kfree_sensitive(data);
_
Patches currently in -mm which might be from sunhao.th@xxxxxxxxx are
mm-new-primitive-kvmemdup.patch
