From 9b3fa47d4a76b1d606a396455f9bbeee083ef008 Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Wed, 13 Dec 2017 15:21:22 -0800
Subject: [PATCH] kobject: fix suppressing modalias in uevents delivered over
netlink
The commit 4a336a23d619 ("kobject: copy env blob in one go") optimized
constructing uevent data for delivery over netlink by using the raw
environment buffer, instead of reconstructing it from individual
environment pointers. Unfortunately in doing so it broke suppressing
MODALIAS attribute for KOBJ_UNBIND events, as the code that suppressed this
attribute only adjusted the environment pointers, but left the buffer
itself alone. Let's fix it by making sure the offending attribute is
obliterated form the buffer as well.
Reported-by: Tariq Toukan <tariqt@mellanox.com>
Reported-by: Casey Leedom <leedom@chelsio.com>
Fixes: 4a336a23d619 ("kobject: copy env blob in one go")
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
lib/kobject_uevent.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index c3e84edc47c96..2615074d3de5c 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -346,7 +346,8 @@ static int kobject_uevent_net_broadcast(struct kobject *kobj,
static void zap_modalias_env(struct kobj_uevent_env *env)
{
static const char modalias_prefix[] = "MODALIAS=";
- int i;
+ size_t len;
+ int i, j;
for (i = 0; i < env->envp_idx;) {
if (strncmp(env->envp[i], modalias_prefix,
@@ -355,11 +356,18 @@ static void zap_modalias_env(struct kobj_uevent_env *env)
continue;
}
- if (i != env->envp_idx - 1)
- memmove(&env->envp[i], &env->envp[i + 1],
- sizeof(env->envp[i]) * env->envp_idx - 1);
+ len = strlen(env->envp[i]) + 1;
+
+ if (i != env->envp_idx - 1) {
+ memmove(env->envp[i], env->envp[i + 1],
+ env->buflen - len);
+
+ for (j = i; j < env->envp_idx - 1; j++)
+ env->envp[j] = env->envp[j + 1] - len;
+ }
env->envp_idx--;
+ env->buflen -= len;
}
}
--
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