linux-kernel - [RFC PATCH v1 17/50] net/802/{garp,mrp}.c: Use prandom_u32

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:   Fri, 29 Nov 2019 17:44:31 -0500
From:   George Spelvin <lkml@....org>
To:     linux-kernel@...r.kernel.org, lkml@....org
Cc:     Aruna-Hewapathirane <aruna.hewapathirane@...il.com>,
        "David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org
Subject: [RFC PATCH v1 17/50] net/802/{garp,mrp}.c: Use prandom_u32_max
 instead of manual equivalent

The previous code was carefully written for efficiency, which is
good, but the helper function is more legible.

Signed-off-by: George Spelvin <lkml@....org>
Cc: Aruna-Hewapathirane <aruna.hewapathirane@...il.com>
Cc: David S. Miller <davem@...emloft.net>
Cc: netdev@...r.kernel.org
---
 net/802/garp.c | 2 +-
 net/802/mrp.c  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/802/garp.c b/net/802/garp.c
index 400bd857e5f57..84a82d1b9ed59 100644
--- a/net/802/garp.c
+++ b/net/802/garp.c
@@ -394,7 +394,7 @@ static void garp_join_timer_arm(struct garp_applicant *app)
 {
 	unsigned long delay;
 
-	delay = (u64)msecs_to_jiffies(garp_join_time) * prandom_u32() >> 32;
+	delay = prandom_u32_max(msecs_to_jiffies(garp_join_time));
 	mod_timer(&app->join_timer, jiffies + delay);
 }
 
diff --git a/net/802/mrp.c b/net/802/mrp.c
index bea6e43d45a0d..bed550772aeb5 100644
--- a/net/802/mrp.c
+++ b/net/802/mrp.c
@@ -579,7 +579,7 @@ static void mrp_join_timer_arm(struct mrp_applicant *app)
 {
 	unsigned long delay;
 
-	delay = (u64)msecs_to_jiffies(mrp_join_time) * prandom_u32() >> 32;
+	delay = prandom_u32_max(msecs_to_jiffies(mrp_join_time));
 	mod_timer(&app->join_timer, jiffies + delay);
 }
 
-- 
2.26.0