From 186f32e2096c7d9cd9106b8dedd79c596f4c8398 Mon Sep 17 00:00:00 2001 From: "Nicholas A. Bellinger" Date: Mon, 16 Jun 2014 20:59:52 +0000 Subject: [PATCH] target: Explicitly clear ramdisk_mcp backend pages [Note that a different patch to address the same issue went in during v3.15-rc1 (commit 4442dc8a), but includes a bunch of other changes that don't strictly apply to fixing the bug] This patch changes rd_allocate_sgl_table() to explicitly clear ramdisk_mcp backend memory pages by passing __GFP_ZERO into alloc_pages(). This addresses a potential security issue where reading from a ramdisk_mcp could return sensitive information, and follows what >= v3.15 does to explicitly clear ramdisk_mcp memory at backend device initialization time. This fixes CVE-2014-4027 Upstream-Status: Backport Reported-by: Jorge Daniel Sequeira Matias Cc: Jorge Daniel Sequeira Matias Signed-off-by: Nicholas Bellinger Signed-off-by: Jiri Slaby Signed-off-by: Sona Sarmadi --- drivers/target/target_core_rd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c index 131327a..9f6bede 100644 --- a/drivers/target/target_core_rd.c +++ b/drivers/target/target_core_rd.c @@ -179,7 +179,7 @@ static int rd_build_device_space(struct rd_dev *rd_dev) - 1; for (j = 0; j < sg_per_table; j++) { - pg = alloc_pages(GFP_KERNEL, 0); + pg = alloc_pages(GFP_KERNEL | __GFP_ZERO, 0); if (!pg) { pr_err("Unable to allocate scatterlist" " pages for struct rd_dev_sg_table\n"); -- 1.9.1