From: Kees Cook Date: Wed, 21 May 2025 21:27:04 +0000 (+0200) Subject: wireguard: global: add __nonstring annotations for unterminated strings X-Git-Tag: v6.16-rc1~132^2~27^2~3 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=71e5da46e78c1cd24e2feed251a2845327447ad8;p=thirdparty%2Fkernel%2Flinux.git wireguard: global: add __nonstring annotations for unterminated strings When a character array without a terminating NUL character has a static initializer, GCC 15's -Wunterminated-string-initialization will only warn if the array lacks the "nonstring" attribute[1]. Mark the arrays with __nonstring to correctly identify the char array as "not a C string" and thereby eliminate the warning: ../drivers/net/wireguard/cookie.c:29:56: warning: initializer-string for array of 'unsigned char' truncates NUL terminator but destination lacks 'nonstring' attribute (9 chars into 8 available) [-Wunterminated-string-initialization] 29 | static const u8 mac1_key_label[COOKIE_KEY_LABEL_LEN] = "mac1----"; | ^~~~~~~~~~ ../drivers/net/wireguard/cookie.c:30:58: warning: initializer-string for array of 'unsigned char' truncates NUL terminator but destination lacks 'nonstring' attribute (9 chars into 8 available) [-Wunterminated-string-initialization] 30 | static const u8 cookie_key_label[COOKIE_KEY_LABEL_LEN] = "cookie--"; | ^~~~~~~~~~ ../drivers/net/wireguard/noise.c:28:38: warning: initializer-string for array of 'unsigned char' truncates NUL terminator but destination lacks 'nonstring' attribute (38 chars into 37 available) [-Wunterminated-string-initialization] 28 | static const u8 handshake_name[37] = "Noise_IKpsk2_25519_ChaChaPoly_BLAKE2s"; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ../drivers/net/wireguard/noise.c:29:39: warning: initializer-string for array of 'unsigned char' truncates NUL terminator but destination lacks 'nonstring' attribute (35 chars into 34 available) [-Wunterminated-string-initialization] 29 | static const u8 identifier_name[34] = "WireGuard v1 zx2c4 Jason@zx2c4.com"; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The arrays are always used with their fixed size, so use __nonstring. Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1] Signed-off-by: Kees Cook Signed-off-by: Jason A. Donenfeld Link: https://patch.msgid.link/20250521212707.1767879-3-Jason@zx2c4.com Signed-off-by: Paolo Abeni --- diff --git a/drivers/net/wireguard/cookie.c b/drivers/net/wireguard/cookie.c index f89581b5e8cbe..94d0a7206084e 100644 --- a/drivers/net/wireguard/cookie.c +++ b/drivers/net/wireguard/cookie.c @@ -26,8 +26,8 @@ void wg_cookie_checker_init(struct cookie_checker *checker, } enum { COOKIE_KEY_LABEL_LEN = 8 }; -static const u8 mac1_key_label[COOKIE_KEY_LABEL_LEN] = "mac1----"; -static const u8 cookie_key_label[COOKIE_KEY_LABEL_LEN] = "cookie--"; +static const u8 mac1_key_label[COOKIE_KEY_LABEL_LEN] __nonstring = "mac1----"; +static const u8 cookie_key_label[COOKIE_KEY_LABEL_LEN] __nonstring = "cookie--"; static void precompute_key(u8 key[NOISE_SYMMETRIC_KEY_LEN], const u8 pubkey[NOISE_PUBLIC_KEY_LEN], diff --git a/drivers/net/wireguard/noise.c b/drivers/net/wireguard/noise.c index 202a33af5a721..7eb9a23a3d4d9 100644 --- a/drivers/net/wireguard/noise.c +++ b/drivers/net/wireguard/noise.c @@ -25,8 +25,8 @@ * <- e, ee, se, psk, {} */ -static const u8 handshake_name[37] = "Noise_IKpsk2_25519_ChaChaPoly_BLAKE2s"; -static const u8 identifier_name[34] = "WireGuard v1 zx2c4 Jason@zx2c4.com"; +static const u8 handshake_name[37] __nonstring = "Noise_IKpsk2_25519_ChaChaPoly_BLAKE2s"; +static const u8 identifier_name[34] __nonstring = "WireGuard v1 zx2c4 Jason@zx2c4.com"; static u8 handshake_init_hash[NOISE_HASH_LEN] __ro_after_init; static u8 handshake_init_chaining_key[NOISE_HASH_LEN] __ro_after_init; static atomic64_t keypair_counter = ATOMIC64_INIT(0);