From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 083808489 for ; Fri, 10 Mar 2023 14:15:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63B58C433EF; Fri, 10 Mar 2023 14:15:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678457725; bh=kd/SeC9jIRhLgozTPhc7Y7tsg4XYWE5Fr9tTqQgpTjw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QDnn6+Gq2nibUIAP3vEBKZJuHh4UQRB4S05DxwdimWTd/Eb51pBMYiWJrXaqihpx4 xKrHD7tHXP51wXBQmm3BByA2NaDsj4TTG/fyfZdxtHm/Hj19Y9WN7iB261nxXh/jKn yrhimElw6tv0VrIXw8dBNeAF0cwyyrQKYOG+l9qo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Roberto Sassu , Herbert Xu , Eric Biggers , Sasha Levin Subject: [PATCH 4.19 037/252] lib/mpi: Fix buffer overrun when SG is too long Date: Fri, 10 Mar 2023 14:36:47 +0100 Message-Id: <20230310133719.950815675@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133718.803482157@linuxfoundation.org> References: <20230310133718.803482157@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Herbert Xu [ Upstream commit 7361d1bc307b926cbca214ab67b641123c2d6357 ] The helper mpi_read_raw_from_sgl sets the number of entries in the SG list according to nbytes. However, if the last entry in the SG list contains more data than nbytes, then it may overrun the buffer because it only allocates enough memory for nbytes. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Reported-by: Roberto Sassu Signed-off-by: Herbert Xu Reviewed-by: Eric Biggers Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- lib/mpi/mpicoder.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c index eead4b3394668..4f73db248009e 100644 --- a/lib/mpi/mpicoder.c +++ b/lib/mpi/mpicoder.c @@ -397,7 +397,8 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes) while (sg_miter_next(&miter)) { buff = miter.addr; - len = miter.length; + len = min_t(unsigned, miter.length, nbytes); + nbytes -= len; for (x = 0; x < len; x++) { a <<= 8; -- 2.39.2