kernel/params.c: fix the maximum length in param_get_string

The length parameter of strlcpy() is supposed to reflect the size of the
target buffer, not of the source string.  Harmless in this case as the
buffer is PAGE_SIZE long and the source string is always much shorter than
this, but conceptually wrong, so let's fix it.

Link: http://lkml.kernel.org/r/20170928162515.24846b4f@endymion
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/params.c b/kernel/params.c
index 1cd8f1a895a8977d2231a00f921582eb7776111e..8283ba045f4f31729288e3304070362ef5564dce 100644 (file)
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -507,7 +507,7 @@ EXPORT_SYMBOL(param_set_copystring);
 int param_get_string(char *buffer, const struct kernel_param *kp)
 {
        const struct kparam_string *kps = kp->str;
-       return strlcpy(buffer, kps->string, kps->maxlen);
+       return strlcpy(buffer, kps->string, PAGE_SIZE);
 }
 EXPORT_SYMBOL(param_get_string);