ANDROID: page_pinner: prevent pp_buffer access before initialization

If page_pinner is configured with page_pinner_enabled=false and
failure_tracking=true, pp_buffer will be accessed without being
initialized. Prevent this by adding page_pinner_inited checks in
functions that access it.

Fixes: 898cfbf094a2 ("ANDROID: mm: introduce page_pinner")
Bug: 259024332
Bug: 260179017
Change-Id: I8f612cae3e74d36e8a4eee5edec25281246cbe5e
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
(cherry picked from commit 23fb3111f63e5fe239a769668275c20493a5849c)
This commit is contained in:
Suren Baghdasaryan 2022-11-27 10:30:33 -08:00
parent cd1d9c42a2
commit 16c2b1d94f
2 changed files with 7 additions and 0 deletions

View File

@ -41,6 +41,9 @@ static inline void dump_page_pinner(struct page *page)
static inline void page_pinner_put_page(struct page *page)
{
if (!static_branch_unlikely(&page_pinner_inited))
return;
if (!static_branch_unlikely(&failure_tracking))
return;
@ -49,6 +52,9 @@ static inline void page_pinner_put_page(struct page *page)
static inline void page_pinner_failure_detect(struct page *page)
{
if (!static_branch_unlikely(&page_pinner_inited))
return;
if (!static_branch_unlikely(&failure_tracking))
return;

View File

@ -57,6 +57,7 @@ static struct longterm_pinner acf_pinner = {
static bool page_pinner_enabled;
DEFINE_STATIC_KEY_FALSE(page_pinner_inited);
EXPORT_SYMBOL(page_pinner_inited);
DEFINE_STATIC_KEY_TRUE(failure_tracking);
EXPORT_SYMBOL(failure_tracking);