From 36f354ec7bf92f8aaf09eaf3b261ea06c25ec337 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= <kw@linux.com>
Date: Wed, 15 Sep 2021 23:01:26 +0000
Subject: [PATCH] PCI/sysfs: Return -EINVAL consistently from "store" functions
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Content-Transfer-Encoding: 8bit
Git-commit: 36f354ec7bf92f8aaf09eaf3b261ea06c25ec337
References: git-fixes
Patch-mainline: v5.16-rc1
Most of the "store" functions that handle userspace input via sysfs return
-EINVAL should the value fail validation and/or type conversion. This
error code is a clear message to userspace that the value is not a valid
input.
However, some of the "show" functions return input parsing error codes
as-is, which may be either -EINVAL or -ERANGE. The former would often be
from kstrtobool(), and the latter typically from other kstr*() functions
such as kstrtou8(), kstrtou32(), kstrtoint(), etc.
-EINVAL is commonly returned as the error code to indicate that the value
provided is invalid, but -ERANGE is not very useful in userspace.
Therefore, normalize the return error code to be -EINVAL for when the
validation and/or type conversion fails.
Link: https://lore.kernel.org/r/20210915230127.2495723-2-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
drivers/pci/endpoint/functions/pci-epf-ntb.c | 18 ++++------
drivers/pci/endpoint/pci-ep-cfs.c | 35 +++++++-------------
drivers/pci/iov.c | 14 ++++----
drivers/pci/pci-sysfs.c | 20 +++++------
4 files changed, 33 insertions(+), 54 deletions(-)
diff --git a/drivers/pci/endpoint/functions/pci-epf-ntb.c b/drivers/pci/endpoint/functions/pci-epf-ntb.c
index 8b4756159f15..e67489144349 100644
--- a/drivers/pci/endpoint/functions/pci-epf-ntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-ntb.c
@@ -1947,11 +1947,9 @@ static ssize_t epf_ntb_##_name##_store(struct config_item *item, \
struct config_group *group = to_config_group(item); \
struct epf_ntb *ntb = to_epf_ntb(group); \
u32 val; \
- int ret; \
\
- ret = kstrtou32(page, 0, &val); \
- if (ret) \
- return ret; \
+ if (kstrtou32(page, 0, &val) < 0) \
+ return -EINVAL; \
\
ntb->_name = val; \
\
@@ -1980,11 +1978,9 @@ static ssize_t epf_ntb_##_name##_store(struct config_item *item, \
struct device *dev = &ntb->epf->dev; \
int win_no; \
u64 val; \
- int ret; \
\
- ret = kstrtou64(page, 0, &val); \
- if (ret) \
- return ret; \
+ if (kstrtou64(page, 0, &val) < 0) \
+ return -EINVAL; \
\
if (sscanf(#_name, "mw%d", &win_no) != 1) \
return -EINVAL; \
@@ -2005,11 +2001,9 @@ static ssize_t epf_ntb_num_mws_store(struct config_item *item,
struct config_group *group = to_config_group(item);
struct epf_ntb *ntb = to_epf_ntb(group);
u32 val;
- int ret;
- ret = kstrtou32(page, 0, &val);
- if (ret)
- return ret;
+ if (kstrtou32(page, 0, &val) < 0)
+ return -EINVAL;
if (val > MAX_MW)
return -EINVAL;
diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
index 999911801877..19bc0e828c0c 100644
--- a/drivers/pci/endpoint/pci-ep-cfs.c
+++ b/drivers/pci/endpoint/pci-ep-cfs.c
@@ -175,9 +175,8 @@ static ssize_t pci_epc_start_store(struct config_item *item, const char *page,
epc = epc_group->epc;
- ret = kstrtobool(page, &start);
- if (ret)
- return ret;
+ if (kstrtobool(page, &start) < 0)
+ return -EINVAL;
if (!start) {
pci_epc_stop(epc);
@@ -329,13 +328,11 @@ static ssize_t pci_epf_##_name##_store(struct config_item *item, \
const char *page, size_t len) \
{ \
u32 val; \
- int ret; \
struct pci_epf *epf = to_pci_epf_group(item)->epf; \
if (WARN_ON_ONCE(!epf->header)) \
return -EINVAL; \
- ret = kstrtou32(page, 0, &val); \
- if (ret) \
- return ret; \
+ if (kstrtou32(page, 0, &val) < 0) \
+ return -EINVAL; \
epf->header->_name = val; \
return len; \
}
@@ -345,13 +342,11 @@ static ssize_t pci_epf_##_name##_store(struct config_item *item, \
const char *page, size_t len) \
{ \
u16 val; \
- int ret; \
struct pci_epf *epf = to_pci_epf_group(item)->epf; \
if (WARN_ON_ONCE(!epf->header)) \
return -EINVAL; \
- ret = kstrtou16(page, 0, &val); \
- if (ret) \
- return ret; \
+ if (kstrtou16(page, 0, &val) < 0) \
+ return -EINVAL; \
epf->header->_name = val; \
return len; \
}
@@ -361,13 +356,11 @@ static ssize_t pci_epf_##_name##_store(struct config_item *item, \
const char *page, size_t len) \
{ \
u8 val; \
- int ret; \
struct pci_epf *epf = to_pci_epf_group(item)->epf; \
if (WARN_ON_ONCE(!epf->header)) \
return -EINVAL; \
- ret = kstrtou8(page, 0, &val); \
- if (ret) \
- return ret; \
+ if (kstrtou8(page, 0, &val) < 0) \
+ return -EINVAL; \
epf->header->_name = val; \
return len; \
}
@@ -376,11 +369,9 @@ static ssize_t pci_epf_msi_interrupts_store(struct config_item *item,
const char *page, size_t len)
{
u8 val;
- int ret;
- ret = kstrtou8(page, 0, &val);
- if (ret)
- return ret;
+ if (kstrtou8(page, 0, &val) < 0)
+ return -EINVAL;
to_pci_epf_group(item)->epf->msi_interrupts = val;
@@ -398,11 +389,9 @@ static ssize_t pci_epf_msix_interrupts_store(struct config_item *item,
const char *page, size_t len)
{
u16 val;
- int ret;
- ret = kstrtou16(page, 0, &val);
- if (ret)
- return ret;
+ if (kstrtou16(page, 0, &val) < 0)
+ return -EINVAL;
to_pci_epf_group(item)->epf->msix_interrupts = val;
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index dafdc652fcd0..0267977c9f17 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -183,11 +183,10 @@ static ssize_t sriov_vf_msix_count_store(struct device *dev,
{
struct pci_dev *vf_dev = to_pci_dev(dev);
struct pci_dev *pdev = pci_physfn(vf_dev);
- int val, ret;
+ int val, ret = 0;
- ret = kstrtoint(buf, 0, &val);
- if (ret)
- return ret;
+ if (kstrtoint(buf, 0, &val) < 0)
+ return -EINVAL;
if (val < 0)
return -EINVAL;
@@ -376,12 +375,11 @@ static ssize_t sriov_numvfs_store(struct device *dev,
const char *buf, size_t count)
{
struct pci_dev *pdev = to_pci_dev(dev);
- int ret;
+ int ret = 0;
u16 num_vfs;
- ret = kstrtou16(buf, 0, &num_vfs);
- if (ret < 0)
- return ret;
+ if (kstrtou16(buf, 0, &num_vfs) < 0)
+ return -EINVAL;
if (num_vfs > pci_sriov_get_totalvfs(pdev))
return -ERANGE;
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 6832e161be1c..a092fc0c665d 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -273,15 +273,14 @@ static ssize_t enable_store(struct device *dev, struct device_attribute *attr,
{
struct pci_dev *pdev = to_pci_dev(dev);
unsigned long val;
- ssize_t result;
+ ssize_t result = 0;
/* this can crash the machine when done on the "wrong" device */
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- result = kstrtoul(buf, 0, &val);
- if (result < 0)
- return result;
+ if (kstrtoul(buf, 0, &val) < 0)
+ return -EINVAL;
device_lock(dev);
if (dev->driver)
@@ -313,14 +312,13 @@ static ssize_t numa_node_store(struct device *dev,
size_t count)
{
struct pci_dev *pdev = to_pci_dev(dev);
- int node, ret;
+ int node;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- ret = kstrtoint(buf, 0, &node);
- if (ret)
- return ret;
+ if (kstrtoint(buf, 0, &node) < 0)
+ return -EINVAL;
if ((node < 0 && node != NUMA_NO_NODE) || node >= MAX_NUMNODES)
return -EINVAL;
@@ -1340,10 +1338,10 @@ static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
{
struct pci_dev *pdev = to_pci_dev(dev);
unsigned long val;
- ssize_t result = kstrtoul(buf, 0, &val);
+ ssize_t result;
- if (result < 0)
- return result;
+ if (kstrtoul(buf, 0, &val) < 0)
+ return -EINVAL;
if (val != 1)
return -EINVAL;
--
2.26.2