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 F018B3AA4E4; Wed, 8 Apr 2026 18:21:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775672463; cv=none; b=gUAra9B+Y2XNgq+DL3x+3pyqwHi6F3vAz3ak8qSyWz1P2ZgIAAucOllYE/yYVrJbPBqIOlSZTogZvq2Ms2yu4KJ0/boQO2peIoVm2r4q+XuU4JcNqkGyCJsk+dpPouT7SwxPn6oxUxLamDSC4Xo0FWA7SAWyZV5eG9gR9vzxxZE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775672463; c=relaxed/simple; bh=JuSeYLFPckp1VUtYNBoF/eXGhI8QbmFLiIqC74OgZGY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cidRiYtjRxZQKu2kIWCSGq7icTVDzstHPnXtYwvBKDEOw70zk3rvhGuDiIoMdJFGDm/LQohCpNu6cxZp83lE/chWAT2Kohz8pDeo8f855qrT3P9i3WZqv0tVh9BAwUZq3+GpBgTkVRgZUE+EzYgb5Yp67VEO2nVdPHSpXcWzJPA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0AS/ZLAX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="0AS/ZLAX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 864E4C19421; Wed, 8 Apr 2026 18:21:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775672462; bh=JuSeYLFPckp1VUtYNBoF/eXGhI8QbmFLiIqC74OgZGY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0AS/ZLAXc7iVxz+TgBiucyW1gvKZHgiJkLLEcIKJ/ZOaISpnNlnn8MLxGayH07qt8 EvOkX/1CUCtizuKCZ9J2BaJuge/6bJ8UU/c5RYNxZv+tx4x49JApvFEjTCICfChQBU hsjhkwQYpe0kbW+D3PThvzDzlCANEWAP1yCaNRXo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Norbert Szetei , Herbert Xu , Sasha Levin Subject: [PATCH 6.6 017/160] crypto: af-alg - fix NULL pointer dereference in scatterwalk Date: Wed, 8 Apr 2026 20:01:44 +0200 Message-ID: <20260408175913.841139274@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260408175913.177092714@linuxfoundation.org> References: <20260408175913.177092714@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Norbert Szetei [ Upstream commit 62397b493e14107ae82d8b80938f293d95425bcb ] The AF_ALG interface fails to unmark the end of a Scatter/Gather List (SGL) when chaining a new af_alg_tsgl structure. If a sendmsg() fills an SGL exactly to MAX_SGL_ENTS, the last entry is marked as the end. A subsequent sendmsg() allocates a new SGL and chains it, but fails to clear the end marker on the previous SGL's last data entry. This causes the crypto scatterwalk to hit a premature end, returning NULL on sg_next() and leading to a kernel panic during dereference. Fix this by explicitly unmarking the end of the previous SGL when performing sg_chain() in af_alg_alloc_tsgl(). Fixes: 8ff590903d5f ("crypto: algif_skcipher - User-space interface for skcipher operations") Signed-off-by: Norbert Szetei Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- crypto/af_alg.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/crypto/af_alg.c b/crypto/af_alg.c index 3d0b7542f771c..24575ceae14bd 100644 --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -622,8 +622,10 @@ static int af_alg_alloc_tsgl(struct sock *sk) sg_init_table(sgl->sg, MAX_SGL_ENTS + 1); sgl->cur = 0; - if (sg) + if (sg) { + sg_unmark_end(sg + MAX_SGL_ENTS - 1); sg_chain(sg, MAX_SGL_ENTS + 1, sgl->sg); + } list_add_tail(&sgl->list, &ctx->tsgl_list); } -- 2.53.0