From 8a7d95f95c95f396decbd4cda6d4903fc4664946 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 17 Mar 2015 17:28:46 +0000 Subject: [PATCH] drivers/base: cacheinfo: validate device node for all the caches On architectures that depend on DT for obtaining cache hierarcy, we need to validate the device node for all the cache indices, failing to do so might result in wrong information being exposed to the userspace. This is quite possible on initial/incomplete versions of the device trees. In such cases, it's better to bail out if all the required device nodes are not present. This patch adds checks for the validation of device node for all the caches and doesn't initialise the cacheinfo if there's any error. Reported-by: Mark Rutland Acked-by: Mark Rutland Signed-off-by: Sudeep Holla Cc: stable # 4.0 Signed-off-by: Greg Kroah-Hartman --- drivers/base/cacheinfo.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index 6e64563361f0..9c2ba1c97c42 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -62,15 +62,21 @@ static int cache_setup_of_node(unsigned int cpu) return -ENOENT; } - while (np && index < cache_leaves(cpu)) { + while (index < cache_leaves(cpu)) { this_leaf = this_cpu_ci->info_list + index; if (this_leaf->level != 1) np = of_find_next_cache_node(np); else np = of_node_get(np);/* cpu node itself */ + if (!np) + break; this_leaf->of_node = np; index++; } + + if (index != cache_leaves(cpu)) /* not all OF nodes populated */ + return -ENOENT; + return 0; } @@ -189,8 +195,11 @@ static int detect_cache_attributes(unsigned int cpu) * will be set up here only if they are not populated already */ ret = cache_shared_cpu_map_setup(cpu); - if (ret) + if (ret) { + pr_warn("Unable to detect cache hierarcy from DT for CPU %d\n", + cpu); goto free_ci; + } return 0; free_ci: