diff options
author | Yisheng Xie <[email protected]> | 2018-03-22 16:17:02 -0700 |
---|---|---|
committer | Linus Torvalds <[email protected]> | 2018-03-22 17:07:01 -0700 |
commit | 8970a63e965b43288c4f5f40efbc2bbf80de7f16 (patch) | |
tree | 5fbccafe8068d97d24f9cb26354cbfe9c0e6b3e1 | |
parent | 3215b9d57a2c75c4305a3956ca303d7004485200 (diff) |
mm/mempolicy.c: avoid use uninitialized preferred_node
Alexander reported a use of uninitialized memory in __mpol_equal(),
which is caused by incorrect use of preferred_node.
When mempolicy in mode MPOL_PREFERRED with flags MPOL_F_LOCAL, it uses
numa_node_id() instead of preferred_node, however, __mpol_equal() uses
preferred_node without checking whether it is MPOL_F_LOCAL or not.
[[email protected]: slight comment tweak]
Link: http://lkml.kernel.org/r/[email protected]
Fixes: fc36b8d3d819 ("mempolicy: use MPOL_F_LOCAL to Indicate Preferred Local Policy")
Signed-off-by: Yisheng Xie <[email protected]>
Reported-by: Alexander Potapenko <[email protected]>
Tested-by: Alexander Potapenko <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: Dmitriy Vyukov <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
-rw-r--r-- | mm/mempolicy.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c index d879f1d8a44a..32cba0332787 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -2124,6 +2124,9 @@ bool __mpol_equal(struct mempolicy *a, struct mempolicy *b) case MPOL_INTERLEAVE: return !!nodes_equal(a->v.nodes, b->v.nodes); case MPOL_PREFERRED: + /* a's ->flags is the same as b's */ + if (a->flags & MPOL_F_LOCAL) + return true; return a->v.preferred_node == b->v.preferred_node; default: BUG(); |