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 A87DE2FB45C; Mon, 5 May 2025 23:23:24 +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=1746487405; cv=none; b=PXnG+v1E101gdqicBSbKqNMDVsrqBuU+Ienmw2G9TQ/KAUWPwRwRMIQ5ir5caEUP2bVpP8QlZtvN7nbh/8TTsQDaDlkD91t/3ljMxW6EpLDeg4iRmVagkRf2Ti6v/6IphXcKLhyKymmcuzjjujg5C/4kvlVFpmwAhGKetYfhejM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746487405; c=relaxed/simple; bh=TLK/nw2rcYQzO6iVjYaqZj4A8EqjcfM5zZQ6+AxLI/4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=opGaJ7c4dT1M0l9LduPh+c3UT2oQg0IfuLGg21HmXPBkfyBd62lArPuZkhKXkz8cb/QM4NRxswvggSnk81XtKVOzYQBi0to2FHHqiM9dk8f0I7i0d+WiscRgcFSu7drMsxRDL8PLNM+K3w82Py6Ojr5bBXqkPlkUfJkbpeT6PLs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mbOJ7T2x; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mbOJ7T2x" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 78A27C4CEE4; Mon, 5 May 2025 23:23:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746487404; bh=TLK/nw2rcYQzO6iVjYaqZj4A8EqjcfM5zZQ6+AxLI/4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mbOJ7T2x03FT5Yn1xinxvVrTkFAlzupqeocTWv8hYJwgREJ2V1zy0xe59acJtlD0H y6yZwIj1/VAeFHr/u3cQCynnigdpU4kBLPyqDIFgbsuX01DPSiTG3WgYjfbQzkR3Z7 vU2PFLxG1cRdHMOpPw7psgE8tObkR6sTGluJzz8BBDJzKNOyQ5Q6kxMTTlLJp8AIjz GZAjBkPgTDRopHNdv0tDvc1T+GXOVicXFpC/mJ2iLJo4CGWKfXk4SHYZyOx5X4m51m jNfTK2iAmelqyOfwkd0RaGuHx1pZt+u2I/ISstjh3otdTM48U5T1ciulElu0Xz/oWL iJGig+ORMJQzQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Peter Seiderer , Simon Horman , Jakub Kicinski , Sasha Levin , davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 51/79] net: pktgen: fix access outside of user given buffer in pktgen_thread_write() Date: Mon, 5 May 2025 19:21:23 -0400 Message-Id: <20250505232151.2698893-51-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505232151.2698893-1-sashal@kernel.org> References: <20250505232151.2698893-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.293 Content-Transfer-Encoding: 8bit From: Peter Seiderer [ Upstream commit 425e64440ad0a2f03bdaf04be0ae53dededbaa77 ] Honour the user given buffer size for the strn_len() calls (otherwise strn_len() will access memory outside of the user given buffer). Signed-off-by: Peter Seiderer Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250219084527.20488-8-ps.report@gmx.net Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/core/pktgen.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/core/pktgen.c b/net/core/pktgen.c index e7cde4f097908..4fd66e6466d29 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -1770,8 +1770,8 @@ static ssize_t pktgen_thread_write(struct file *file, i = len; /* Read variable name */ - - len = strn_len(&user_buffer[i], sizeof(name) - 1); + max = min(sizeof(name) - 1, count - i); + len = strn_len(&user_buffer[i], max); if (len < 0) return len; @@ -1801,7 +1801,8 @@ static ssize_t pktgen_thread_write(struct file *file, if (!strcmp(name, "add_device")) { char f[32]; memset(f, 0, 32); - len = strn_len(&user_buffer[i], sizeof(f) - 1); + max = min(sizeof(f) - 1, count - i); + len = strn_len(&user_buffer[i], max); if (len < 0) { ret = len; goto out; -- 2.39.5