The patch titled
Subject: mm: fix division by 0 in percpu_pagelist_fraction()
has been added to the -mm tree. Its filename is
mm-fix-division-by-0-in-percpu_pagelist_fraction.patch
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From: Sasha Levin <levinsasha928@xxxxxxxxx>
Subject: mm: fix division by 0 in percpu_pagelist_fraction()
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>
Reviewed-by: Minchan Kim <minchan@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff -puN mm/page_alloc.c~mm-fix-division-by-0-in-percpu_pagelist_fraction mm/page_alloc.c
--- a/mm/page_alloc.c~mm-fix-division-by-0-in-percpu_pagelist_fraction
+++ a/mm/page_alloc.c
@@ -106,7 +106,7 @@ unsigned long totalreserve_pages __read_
*/
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_hand
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) {
_
Subject: Subject: mm: fix division by 0 in percpu_pagelist_fraction()
Patches currently in -mm which might be from levinsasha928@xxxxxxxxx are
linux-next.patch
mm-fix-division-by-0-in-percpu_pagelist_fraction.patch
brlocks-lglocks-cleanups.patch
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