mm/page_owner: avoid null pointer dereference
We have dereferenced page_ext before checking it. Lets check it first
and then used it.
Fixes: f86e427197
("mm: check the return value of lookup_page_ext for all call sites")
Link: http://lkml.kernel.org/r/1465249059-7883-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
7c5b723946
commit
8285027fc4
1 changed files with 4 additions and 2 deletions
|
@ -207,13 +207,15 @@ void __dump_page_owner(struct page *page)
|
|||
.nr_entries = page_ext->nr_entries,
|
||||
.entries = &page_ext->trace_entries[0],
|
||||
};
|
||||
gfp_t gfp_mask = page_ext->gfp_mask;
|
||||
int mt = gfpflags_to_migratetype(gfp_mask);
|
||||
gfp_t gfp_mask;
|
||||
int mt;
|
||||
|
||||
if (unlikely(!page_ext)) {
|
||||
pr_alert("There is not page extension available.\n");
|
||||
return;
|
||||
}
|
||||
gfp_mask = page_ext->gfp_mask;
|
||||
mt = gfpflags_to_migratetype(gfp_mask);
|
||||
|
||||
if (!test_bit(PAGE_EXT_OWNER, &page_ext->flags)) {
|
||||
pr_alert("page_owner info is not active (free page?)\n");
|
||||
|
|
Loading…
Reference in a new issue