Commit b0a8cc58 authored by Takamori Yamaguchi's avatar Takamori Yamaguchi Committed by Linus Torvalds

mm: bugfix: set current->reclaim_state to NULL while returning from kswapd()

In kswapd(), set current->reclaim_state to NULL before returning, as
current->reclaim_state holds reference to variable on kswapd()'s stack.

In rare cases, while returning from kswapd() during memory offlining,
__free_slab() and freepages() can access the dangling pointer of
current->reclaim_state.
Signed-off-by: default avatarTakamori Yamaguchi <takamori.yamaguchi@jp.sony.com>
Signed-off-by: default avatarAaditya Kumar <aaditya.kumar@ap.sony.com>
Acked-by: default avatarDavid Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 848561d3
...@@ -3017,6 +3017,8 @@ static int kswapd(void *p) ...@@ -3017,6 +3017,8 @@ static int kswapd(void *p)
&balanced_classzone_idx); &balanced_classzone_idx);
} }
} }
current->reclaim_state = NULL;
return 0; return 0;
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment