leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

crypto: caam - map src buffer before access

Browse Source 
KMap the buffers before copying trailing bytes during hmac into a session
temporary buffer. This is required if pinned buffer from user-space is send
during hmac and is safe even if hmac request is generated from within kernel.

Signed-off-by: Yashpal Dutta <yashpal.dutta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Yashpal Dutta 2013-09-11 19:24:06 +00:00 committed by Herbert Xu
parent 1005bccd7a
commit 82ad6bcade
1 changed files with 25 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
drivers/crypto/caam/sg_sw_sec4.h
View File

@ -117,6 +117,21 @@ static int dma_unmap_sg_chained(struct device *dev, struct scatterlist *sg,
return nents;
}
/* Map SG page in kernel virtual address space and copy */
static inline void sg_map_copy(u8 *dest, struct scatterlist *sg,
int len, int offset)
{
u8 *mapped_addr;
/*
* Page here can be user-space pinned using get_user_pages
* Same must be kmapped before use and kunmapped subsequently
*/
mapped_addr = kmap_atomic(sg_page(sg));
memcpy(dest, mapped_addr + offset, len);
kunmap_atomic(mapped_addr);
}
/* Copy from len bytes of sg to dest, starting from beginning */
static inline void sg_copy(u8 *dest, struct scatterlist *sg, unsigned int len)
{
@ -124,15 +139,15 @@ static inline void sg_copy(u8 *dest, struct scatterlist *sg, unsigned int len)
int cpy_index = 0, next_cpy_index = current_sg->length;
while (next_cpy_index < len) {
memcpy(dest + cpy_index, (u8 *) sg_virt(current_sg),
current_sg->length);
sg_map_copy(dest + cpy_index, current_sg, current_sg->length,
current_sg->offset);
current_sg = scatterwalk_sg_next(current_sg);
cpy_index = next_cpy_index;
next_cpy_index += current_sg->length;
}
if (cpy_index < len)
memcpy(dest + cpy_index, (u8 *) sg_virt(current_sg),
len - cpy_index);
sg_map_copy(dest + cpy_index, current_sg, len-cpy_index,
current_sg->offset);
}
/* Copy sg data, from to_skip to end, to dest */
@ -140,7 +155,7 @@ static inline void sg_copy_part(u8 *dest, struct scatterlist *sg,
int to_skip, unsigned int end)
{
struct scatterlist *current_sg = sg;
int sg_index, cpy_index;
int sg_index, cpy_index, offset;
sg_index = current_sg->length;
while (sg_index <= to_skip) {
@ -148,9 +163,10 @@ static inline void sg_copy_part(u8 *dest, struct scatterlist *sg,
sg_index += current_sg->length;
}
cpy_index = sg_index - to_skip;
memcpy(dest, (u8 *) sg_virt(current_sg) +
current_sg->length - cpy_index, cpy_index);
current_sg = scatterwalk_sg_next(current_sg);
if (end - sg_index)
offset = current_sg->offset + current_sg->length - cpy_index;
sg_map_copy(dest, current_sg, cpy_index, offset);
if (end - sg_index) {
current_sg = scatterwalk_sg_next(current_sg);
sg_copy(dest + cpy_index, current_sg, end - sg_index);
}
}