percpu_pagelist_fraction_sysctl_handler() has only considered -EINVAL as a possible error
from proc_dointvec_minmax(). If any other error is returned, it would proceed to divide by
zero since percpu_pagelist_fraction wasn't getting initialized at any point. For example,
writing 0 bytes into the proc file would trigger the issue.
Signed-off-by: Sasha Levin <levinsasha928@xxxxxxxxx>
---
mm/page_alloc.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 1b951de..1e00729 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -106,7 +106,7 @@ unsigned long totalreserve_pages __read_mostly;
*/
unsigned long dirty_balance_reserve __read_mostly;
-int percpu_pagelist_fraction;
+int percpu_pagelist_fraction = 8;
gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
#ifdef CONFIG_PM_SLEEP
@@ -5271,7 +5271,7 @@ int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
int ret;
ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
- if (!write || (ret == -EINVAL))
+ if (!write || (ret < 0))
return ret;
for_each_populated_zone(zone) {
for_each_possible_cpu(cpu) {
--
1.7.8.5
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>