strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.
[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89
Signed-off-by: Azeem Shaikh <[email protected]>
---
fs/vboxsf/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
index d2f6df69f611..1fb8f4df60cb 100644
--- a/fs/vboxsf/super.c
+++ b/fs/vboxsf/super.c
@@ -176,7 +176,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
}
folder_name->size = size;
folder_name->length = size - 1;
- strlcpy(folder_name->string.utf8, fc->source, size);
+ strscpy(folder_name->string.utf8, fc->source, size);
err = vboxsf_map_folder(folder_name, &sbi->root);
kfree(folder_name);
if (err) {
--
2.40.1.521.gf1e218fcd8-goog
Hi,
On 5/10/23 23:11, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> No return values were used, so direct replacement is safe.
>
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> [2] https://github.com/KSPP/linux/issues/89
>
> Signed-off-by: Azeem Shaikh <[email protected]>
Thanks, patch looks good to me:
Reviewed-by: Hans de Goede <[email protected]>
Regards,
Hans
> ---
> fs/vboxsf/super.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
> index d2f6df69f611..1fb8f4df60cb 100644
> --- a/fs/vboxsf/super.c
> +++ b/fs/vboxsf/super.c
> @@ -176,7 +176,7 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
> }
> folder_name->size = size;
> folder_name->length = size - 1;
> - strlcpy(folder_name->string.utf8, fc->source, size);
> + strscpy(folder_name->string.utf8, fc->source, size);
> err = vboxsf_map_folder(folder_name, &sbi->root);
> kfree(folder_name);
> if (err) {
On Wed, May 10, 2023 at 09:11:46PM +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> No return values were used, so direct replacement is safe.
>
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> [2] https://github.com/KSPP/linux/issues/89
>
> Signed-off-by: Azeem Shaikh <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
--
Kees Cook
On Wed, 10 May 2023 21:11:46 +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> No return values were used, so direct replacement is safe.
>
> [...]
Applied to for-next/hardening, thanks!
[1/1] vboxsf: Replace all non-returning strlcpy with strscpy
https://git.kernel.org/kees/c/883f8fe87686
--
Kees Cook