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 5.15-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-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ce0b5bbcccafb9b52b73af808b0ca3a92e1f7bc6 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 de6cbcf69bbd6..b05020657cdc8 100644 --- a/crypto/xts.c +++ b/crypto/xts.c @@ -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] != ')')