From: Takamori Yamaguchi <[email protected]> Subject: 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: Takamori Yamaguchi <[email protected]> Signed-off-by: Aaditya Kumar <[email protected]> Acked-by: David Rientjes <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> --- mm/vmscan.c | 2 ++ 1 file changed, 2 insertions(+) diff -puN mm/vmscan.c~mm-bugfix-set-current-reclaim_state-to-null-while-returning-from-kswapd mm/vmscan.c --- a/mm/vmscan.c~mm-bugfix-set-current-reclaim_state-to-null-while-returning-from-kswapd +++ a/mm/vmscan.c @@ -3017,6 +3017,8 @@ static int kswapd(void *p) &balanced_classzone_idx); } } + + current->reclaim_state = NULL; return 0; } _ -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
