From 0c8463632c166ae1e5bf10c6314ed62f33f2e68e Mon Sep 17 00:00:00 2001 From: Zijun Hu Date: Wed, 24 Jul 2024 21:54:48 +0800 Subject: [PATCH] driver core: bus: Return -EIO instead of 0 when show/store invalid bus attribute BugLink: https://bugs.launchpad.net/bugs/2097301 [ Upstream commit c0fd973c108cdc22a384854bc4b3e288a9717bb2 ] Return -EIO instead of 0 for below erroneous bus attribute operations: - read a bus attribute without show(). - write a bus attribute without store(). Signed-off-by: Zijun Hu Link: https://lore.kernel.org/r/20240724-bus_fix-v2-1-5adbafc698fb@quicinc.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin Signed-off-by: Manuel Diewald Signed-off-by: Koichiro Den --- drivers/base/bus.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 08362ecec0ec..6a68734e7ebd 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -152,7 +152,8 @@ static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, { struct bus_attribute *bus_attr = to_bus_attr(attr); struct subsys_private *subsys_priv = to_subsys_private(kobj); - ssize_t ret = 0; + /* return -EIO for reading a bus attribute without show() */ + ssize_t ret = -EIO; if (bus_attr->show) ret = bus_attr->show(subsys_priv->bus, buf); @@ -164,7 +165,8 @@ static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, { struct bus_attribute *bus_attr = to_bus_attr(attr); struct subsys_private *subsys_priv = to_subsys_private(kobj); - ssize_t ret = 0; + /* return -EIO for writing a bus attribute without store() */ + ssize_t ret = -EIO; if (bus_attr->store) ret = bus_attr->store(subsys_priv->bus, buf, count);