We found at least one situation where the safe pages list was empty and get_buffer() would gladly try to use a NULL pointer.
Signed-off-by: Brian Geffon bgeffon@google.com Fixes: 8357376 ("swsusp: Improve handling of highmem") Cc: stable@vger.kernel.org
Change-Id: Ibb43a9b4ac5ff2d7e3021fdacc08e116650231e9 --- kernel/power/snapshot.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 362e6bae5891..2dcb33248518 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -2544,8 +2544,9 @@ static void *get_highmem_page_buffer(struct page *page, pbe->copy_page = pfn_to_page(pfn); } else { /* Copy of the page will be stored in normal memory */ - kaddr = safe_pages_list; - safe_pages_list = safe_pages_list->next; + kaddr = __get_safe_page(ca->gfp_mask); + if (!kaddr) + return ERR_PTR(-ENOMEM); pbe->copy_page = virt_to_page(kaddr); } pbe->next = highmem_pblist; @@ -2747,8 +2748,9 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca) return ERR_PTR(-ENOMEM); } pbe->orig_address = page_address(page); - pbe->address = safe_pages_list; - safe_pages_list = safe_pages_list->next; + pbe->address = __get_safe_page(ca->gfp_mask); + if (!pbe->address) + return ERR_PTR(-ENOMEM); pbe->next = restore_pblist; restore_pblist = pbe; return pbe->address;