2019-09-11 12:51:11

by Sandro Volery

Subject: [PATCH v3] Staging: exfat: Avoid use of strcpy

Use strscpy instead of strcpy in exfat_core.c, and add a check
for length that will return already known FFS_INVALIDPATH.

Suggested-by: Rasmus Villemoes <[email protected]>
Signed-off-by: Sandro Volery <[email protected]>
---
v3: Fixed replacing mistake
v2: Introduced length check
v1: Original patch
drivers/staging/exfat/exfat_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/exfat/exfat_core.c b/drivers/staging/exfat/exfat_core.c
index da8c58149c35..4c40f1352848 100644
--- a/drivers/staging/exfat/exfat_core.c
+++ b/drivers/staging/exfat/exfat_core.c
@@ -2964,7 +2964,8 @@ s32 resolve_path(struct inode *inode, char *path, struct chain_t *p_dir,
if (strlen(path) >= (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
return FFS_INVALIDPATH;

- strcpy(name_buf, path);
+ if (strscpy(name_buf, path, sizeof(name_buf)) < 0)
+ return FFS_INVALIDPATH;

nls_cstring_to_uniname(sb, p_uniname, name_buf, &lossy);
if (lossy)
--
2.23.0

2019-09-11 12:56:37

by Dan Carpenter

Subject: Re: [PATCH v3] Staging: exfat: Avoid use of strcpy

On Wed, Sep 11, 2019 at 02:48:12PM +0200, Sandro Volery wrote:
> Use strscpy instead of strcpy in exfat_core.c, and add a check
> for length that will return already known FFS_INVALIDPATH.
>
> Suggested-by: Rasmus Villemoes <[email protected]>
> Signed-off-by: Sandro Volery <[email protected]>
> ---
> v3: Fixed replacing mistake
> v2: Introduced length check
> v1: Original patch
> drivers/staging/exfat/exfat_core.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/staging/exfat/exfat_core.c b/drivers/staging/exfat/exfat_core.c
> index da8c58149c35..4c40f1352848 100644
> --- a/drivers/staging/exfat/exfat_core.c
> +++ b/drivers/staging/exfat/exfat_core.c
> @@ -2964,7 +2964,8 @@ s32 resolve_path(struct inode *inode, char *path, struct chain_t *p_dir,
> if (strlen(path) >= (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Get rid of this.

> return FFS_INVALIDPATH;
>
> - strcpy(name_buf, path);
> + if (strscpy(name_buf, path, sizeof(name_buf)) < 0)
> + return FFS_INVALIDPATH;

regards,
dan carpenter