queue-4.19/mm-cma.c-fix-crash-on-cma-allocation-if-bitmap-alloc.patch

   1 From 98920dbbf1e25afa93779056ed770ad512d1b6ac Mon Sep 17 00:00:00 2001
   2 From: Yue Hu <huyue2@yulong.com>
   3 Date: Mon, 13 May 2019 17:18:14 -0700
   4 Subject: mm/cma.c: fix crash on CMA allocation if bitmap allocation fails
   5
   6 [ Upstream commit 1df3a339074e31db95c4790ea9236874b13ccd87 ]
   7
   8 f022d8cb7ec7 ("mm: cma: Don't crash on allocation if CMA area can't be
   9 activated") fixes the crash issue when activation fails via setting
  10 cma->count as 0, same logic exists if bitmap allocation fails.
  11
  12 Link: http://lkml.kernel.org/r/20190325081309.6004-1-zbestahu@gmail.com
  13 Signed-off-by: Yue Hu <huyue2@yulong.com>
  14 Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
  15 Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
  16 Cc: Laura Abbott <labbott@redhat.com>
  17 Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
  18 Cc: Randy Dunlap <rdunlap@infradead.org>
  19 Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
  20 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
  21 Signed-off-by: Sasha Levin <sashal@kernel.org>
  22 ---
  23  mm/cma.c | 4 +++-
  24  1 file changed, 3 insertions(+), 1 deletion(-)
  25
  26 diff --git a/mm/cma.c b/mm/cma.c
  27 index bfe9f5397165..6ce6e22f82d9 100644
  28 --- a/mm/cma.c
  29 +++ b/mm/cma.c
  30 @@ -106,8 +106,10 @@ static int __init cma_activate_area(struct cma *cma)
  31
  32         cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
  33
  34 -       if (!cma->bitmap)
  35 +       if (!cma->bitmap) {
  36 +               cma->count = 0;
  37                 return -ENOMEM;
  38 +       }
  39
  40         WARN_ON_ONCE(!pfn_valid(pfn));
  41         zone = page_zone(pfn_to_page(pfn));
  42 --
  43 2.20.1
  44