On Fri, 17 Mar 2017 10:29:39 +0800
chenwy <chenwy-f...@cn.fujitsu.com> wrote:
> We should prevent user to operating mtd device with
> an illegal offset or length.
I realize that all the tests you do here are already done in mtdcore.c.
If one is missing, please patch mtdcore.c instead.
Thanks,
Boris
>
> Signed-off-by: Chen Wenyong <chenwy-f...@cn.fujitsu.com>
> ---
> drivers/mtd/devices/mtdram.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/mtd/devices/mtdram.c b/drivers/mtd/devices/mtdram.c
> index cbd8547..83e1603 100644
> --- a/drivers/mtd/devices/mtdram.c
> +++ b/drivers/mtd/devices/mtdram.c
> @@ -58,6 +58,10 @@ static int ram_erase(struct mtd_info *mtd, struct
> erase_info *instr)
> {
> if (check_offs_len(mtd, instr->addr, instr->len))
> return -EINVAL;
> + if (mtd->size < (instr->len + instr->addr) || instr->addr < 0
> + || instr->len < 0)
> + return -EINVAL;
> +
> memset((char *)mtd->priv + instr->addr, 0xff, instr->len);
> instr->state = MTD_ERASE_DONE;
> mtd_erase_callback(instr);
> @@ -67,6 +71,9 @@ static int ram_erase(struct mtd_info *mtd, struct
> erase_info *instr)
> static int ram_point(struct mtd_info *mtd, loff_t from, size_t len,
> size_t *retlen, void **virt, resource_size_t *phys)
> {
> + if (mtd->size < (len + from) || from < 0 || len < 0)
> + return -EINVAL;
> +
> *virt = mtd->priv + from;
> *retlen = len;
> return 0;
> @@ -74,6 +81,9 @@ static int ram_point(struct mtd_info *mtd, loff_t from,
> size_t len,
>
> static int ram_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
> {
> + if (mtd->size < (len + from) || from < 0 || len < 0)
> + return -EINVAL;
> +
> return 0;
> }
>
> @@ -93,6 +103,9 @@ static unsigned long ram_get_unmapped_area(struct mtd_info
> *mtd,
> static int ram_read(struct mtd_info *mtd, loff_t from, size_t len,
> size_t *retlen, u_char *buf)
> {
> + if (mtd->size < (len + from) || from < 0 || len < 0)
> + return -EINVAL;
> +
> memcpy(buf, mtd->priv + from, len);
> *retlen = len;
> return 0;
> @@ -101,6 +114,9 @@ static int ram_read(struct mtd_info *mtd, loff_t from,
> size_t len,
> static int ram_write(struct mtd_info *mtd, loff_t to, size_t len,
> size_t *retlen, const u_char *buf)
> {
> + if (mtd->size < (len + to) || to < 0 || len < 0)
> + return -EINVAL;
> +
> memcpy((char *)mtd->priv + to, buf, len);
> *retlen = len;
> return 0;
