From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AF3F93C871E; Tue, 6 Oct 2026 08:35:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791275740; cv=none; b=riNoijefbVWfKiTUNad7Dx4zC4MIKB+IeC4SQ86xWVBVDGqAyLoRzJULjoHJIyvOflPiOaFi7Psp0k9q10dyCjEzBNFxAWwpR1h/ZlV2B3VThm7ZCmdmW6EfqrCqVlz/8aDSnAodP9+kjaKFHDKox5B8Js0ICjMEWzPhvwfUIY0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791275740; c=relaxed/simple; bh=9eJD3A/h+7Xu1zNmMcrerWDoMWr/yNipexMr60RpsZ8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=mhNPSC+BJFmmTqqpHn0Mn58XGQYQDmyN8VeIDaf0PT45ZTVc5bM/ncsAOB82qg/kHes5o+8umCY9jReM8idnZJHtz7w8IUD1qY4vxWWzkQYSWMjT0ENzSf2QxxWLDjhBNnhcvv5lwN4zSBdKRz/CQjvgefJvmj9jVMgciDFpY10= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=h3UkQGmZ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="h3UkQGmZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 584FD1F000FF; Tue, 6 Oct 2026 08:35:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791275739; bh=9kAGnm6WKEBB8Q/yVVpPtBraDvfpu6wEiPKRs9xavOU=; h=From:To:Cc:Subject:Date; b=h3UkQGmZMi9LhJhd3Vcmc8yg5IyU5m/YUeX4+GVjGWy/aevGNACB4/BVyZhytCDoK paRjJfiWGMWaKTII+sS1oTQG3fSlpdpM8Z/g4EH76MrACQxI/1DE0M9jNTr9HqPRBJ 4eCkwW6PKiFg4Uc5aAT8pDRvjD6xJRZ90cy0Q8zhH1TZbnEnXpfU+eSSFTBp/eX1Qa dG5IK6Qr1L11RBI42MQdo5OJPN31q7YIo22dHTKiIBszuqEfkGtOJjlOsj0kENl8+V vf1yurfGNwD+YgxM3+CRL68eorfTlt6w5xlPzkVXo3ml3kqX7mMf928b3kRYg0NPk9 bHUhLzCbujVqw== From: Eric Biggers To: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ard Biesheuvel , "Jason A . Donenfeld" , Herbert Xu , Eric Biggers , stable@vger.kernel.org, Sashiko Subject: [PATCH] lib/crypto: poly1305: Use memzero_explicit() in poly1305_final() Date: Tue, 6 Oct 2026 10:34:32 +0200 Message-ID: <20261006083432.16328-1-ebiggers@kernel.org> X-Mailer: git-send-email 2.56.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Use memzero_explicit() instead of a plain struct assignment to guarantee zeroization of the 'struct poly1305_desc_ctx'. Note that dead store elimination was only theoretically possible with link-time optimization here. But it's still worth fixing. Fixes: a1d93064094c ("crypto: poly1305 - expose init/update/final library interface") Cc: stable@vger.kernel.org Reported-by: Sashiko Closes: https://sashiko.dev/#/bug/linux-c3a6bd76-f6ab-4203-892a-cd06f7aa0c34 Signed-off-by: Eric Biggers --- lib/crypto/poly1305.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/crypto/poly1305.c b/lib/crypto/poly1305.c index f313ccc4b4dd2..048c7afe86138 100644 --- a/lib/crypto/poly1305.c +++ b/lib/crypto/poly1305.c @@ -78,7 +78,7 @@ void poly1305_final(struct poly1305_desc_ctx *desc, u8 *dst) } poly1305_emit(&desc->state.h, dst, desc->s); - *desc = (struct poly1305_desc_ctx){}; + memzero_explicit(desc, sizeof(*desc)); } EXPORT_SYMBOL(poly1305_final); base-commit: 6a50ce0af5c91fd665d65d357af8ae55db1df7d0 -- 2.56.0