crypto: lrw,xts - Replace strlcpy with strscpy

[ Upstream commit babb80b3ec ]

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().

Direct replacement is safe here since return value of -errno
is used to check for truncation instead of sizeof(dest).

[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 <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Azeem Shaikh 2023-06-20 20:08:32 +00:00 committed by Greg Kroah-Hartman
parent ac70101e5b
commit ad58d7ebbf
2 changed files with 6 additions and 6 deletions

View File

@ -357,10 +357,10 @@ static int lrw_create(struct crypto_template *tmpl, struct rtattr **tb)
* cipher name.
*/
if (!strncmp(cipher_name, "ecb(", 4)) {
unsigned len;
int len;
len = strlcpy(ecb_name, cipher_name + 4, sizeof(ecb_name));
if (len < 2 || len >= sizeof(ecb_name))
len = strscpy(ecb_name, cipher_name + 4, sizeof(ecb_name));
if (len < 2)
goto err_free_inst;
if (ecb_name[len - 1] != ')')

View File

@ -396,10 +396,10 @@ static int xts_create(struct crypto_template *tmpl, struct rtattr **tb)
* cipher name.
*/
if (!strncmp(cipher_name, "ecb(", 4)) {
unsigned len;
int len;
len = strlcpy(ctx->name, cipher_name + 4, sizeof(ctx->name));
if (len < 2 || len >= sizeof(ctx->name))
len = strscpy(ctx->name, cipher_name + 4, sizeof(ctx->name));
if (len < 2)
goto err_free_inst;
if (ctx->name[len - 1] != ')')