[131/155] mm/compaction: really limit compact_unevictable_allowed to 0 and 1

Commit Message

Andrew Morton April 2, 2020, 4:10 a.m. UTC

From: Sebastian Andrzej Siewior <[e-mail]>
Subject: mm/compaction: really limit compact_unevictable_allowed to 0 and 1

The proc file `compact_unevictable_allowed' should allow 0 and 1 only, the
`extra*' attribues have been set properly but without
proc_dointvec_minmax() as the `proc_handler' the limit will not be
enforced.

Use proc_dointvec_minmax() as the `proc_handler' to enfoce the valid
specified range.

Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Sebastian Andrzej Siewior <[e-mail]>
Reviewed-by: Andrew Morton <[e-mail]>
Acked-by: Vlastimil Babka <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Luis Chamberlain <[e-mail]>
Cc: Kees Cook <[e-mail]>
Cc: Iurii Zaikin <[e-mail]>
Cc: Mel Gorman <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 kernel/sysctl.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

--- a/kernel/sysctl.c~really-limit-compact_unevictable_allowed-to-0-and-1
+++ a/kernel/sysctl.c
@@ -1467,7 +1467,7 @@  static struct ctl_table vm_table[] = {
 		.data		= &sysctl_compact_unevictable_allowed,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
+		.proc_handler	= proc_dointvec_minmax,
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},