Commit 9b3fa47d authored Dec 13, 2017 by Dmitry Torokhov Committed by Greg Kroah-Hartman Dec 21, 2017

kobject: fix suppressing modalias in uevents delivered over netlink



The commit 4a336a23 ("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: 4a336a23 ("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>

parent f57ab9a0

lib/kobject_uevent.c

+12 −4

Original line number	Diff line number	Diff line
		@@ -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;
		}
		}

Admin message