diff options
| author | Yashpal Dutta <yashpal.dutta@freescale.com> | 2013-09-11 21:24:06 +0200 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2013-09-23 22:02:20 +0200 |
| commit | 82ad6bcadeb87c2a289e714a680eadba294294df (patch) | |
| tree | d63f1702bdda17af9487f4621b15fb4b0ea9fa6b /drivers/crypto | |
| parent | crypto: caam - enable instantiation of all RNG4 state handles (diff) | |
| download | linux-82ad6bcadeb87c2a289e714a680eadba294294df.tar.xz linux-82ad6bcadeb87c2a289e714a680eadba294294df.zip | |
crypto: caam - map src buffer before access
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>
Diffstat (limited to 'drivers/crypto')
| -rw-r--r-- | drivers/crypto/caam/sg_sw_sec4.h | 34 |
1 files changed, 25 insertions, 9 deletions
diff --git a/drivers/crypto/caam/sg_sw_sec4.h b/drivers/crypto/caam/sg_sw_sec4.h index e0037c8ee243..b12ff85f4241 100644 --- a/drivers/crypto/caam/sg_sw_sec4.h +++ b/drivers/crypto/caam/sg_sw_sec4.h @@ -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); + } } |