This is a note to let you know that I've just added the patch titled
crypto: lrw,xts - Replace strlcpy with strscpy
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
crypto-lrw-xts-replace-strlcpy-with-strscpy.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 18f8ade8535b7976527276636a2e8847d446624e
Author: Azeem Shaikh <azeemshaikh38@xxxxxxxxx>
Date: Tue Jun 20 20:08:32 2023 +0000
crypto: lrw,xts - Replace strlcpy with strscpy
[ Upstream commit babb80b3ecc6f40c962e13c654ebcd27f25ee327 ]
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@xxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/crypto/lrw.c b/crypto/lrw.c
index bcf09fbc750af..80d9076e42e0b 100644
--- a/crypto/lrw.c
+++ b/crypto/lrw.c
@@ -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] != ')')
diff --git a/crypto/xts.c b/crypto/xts.c
index c6a105dba38b9..74dc199d54867 100644
--- a/crypto/xts.c
+++ b/crypto/xts.c
@@ -395,10 +395,10 @@ 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] != ')')
