device_create_file() could fail and return an error code. The fix
captures the error and returns the error code upstream in case it
indeed failed.
Signed-off-by: Kangjie Lu <[email protected]>
---
drivers/usb/storage/sierra_ms.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/usb/storage/sierra_ms.c b/drivers/usb/storage/sierra_ms.c
index 6ac60abd2e15..2c049e3a56eb 100644
--- a/drivers/usb/storage/sierra_ms.c
+++ b/drivers/usb/storage/sierra_ms.c
@@ -195,6 +195,10 @@ int sierra_ms_init(struct us_data *us)
}
complete:
result = device_create_file(&us->pusb_intf->dev, &dev_attr_truinst);
+ if (result) {
+ kfree(swocInfo);
+ return result;
+ }
return 0;
}
--
2.17.1
Hi Kangjie,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on usb/usb-testing]
[also build test WARNING on v5.1-rc2 next-20190322]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Kangjie-Lu/usb-sierra-fix-a-missing-check-of-device_create_file/20190325-101328
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
config: x86_64-randconfig-x009-201912 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
All warnings (new ones prefixed by >>):
drivers/usb/storage/sierra_ms.c: In function 'sierra_ms_init':
>> drivers/usb/storage/sierra_ms.c:199:3: warning: 'swocInfo' may be used uninitialized in this function [-Wmaybe-uninitialized]
kfree(swocInfo);
^~~~~~~~~~~~~~~
vim +/swocInfo +199 drivers/usb/storage/sierra_ms.c
126
127 int sierra_ms_init(struct us_data *us)
128 {
129 int result, retries;
130 struct swoc_info *swocInfo;
131 struct usb_device *udev;
132 struct Scsi_Host *sh;
133
134 retries = 3;
135 result = 0;
136 udev = us->pusb_dev;
137
138 sh = us_to_host(us);
139 scsi_get_host_dev(sh);
140
141 /* Force Modem mode */
142 if (swi_tru_install == TRU_FORCE_MODEM) {
143 usb_stor_dbg(us, "SWIMS: Forcing Modem Mode\n");
144 result = sierra_set_ms_mode(udev, SWIMS_SET_MODE_Modem);
145 if (result < 0)
146 usb_stor_dbg(us, "SWIMS: Failed to switch to modem mode\n");
147 return -EIO;
148 }
149 /* Force Mass Storage mode (keep CD-Rom) */
150 else if (swi_tru_install == TRU_FORCE_MS) {
151 usb_stor_dbg(us, "SWIMS: Forcing Mass Storage Mode\n");
152 goto complete;
153 }
154 /* Normal TRU-Install Logic */
155 else {
156 usb_stor_dbg(us, "SWIMS: Normal SWoC Logic\n");
157
158 swocInfo = kmalloc(sizeof(struct swoc_info),
159 GFP_KERNEL);
160 if (!swocInfo)
161 return -ENOMEM;
162
163 retries = 3;
164 do {
165 retries--;
166 result = sierra_get_swoc_info(udev, swocInfo);
167 if (result < 0) {
168 usb_stor_dbg(us, "SWIMS: Failed SWoC query\n");
169 schedule_timeout_uninterruptible(2*HZ);
170 }
171 } while (retries && result < 0);
172
173 if (result < 0) {
174 usb_stor_dbg(us, "SWIMS: Completely failed SWoC query\n");
175 kfree(swocInfo);
176 return -EIO;
177 }
178
179 debug_swoc(&us->pusb_dev->dev, swocInfo);
180
181 /*
182 * If there is not Linux software on the TRU-Install device
183 * then switch to modem mode
184 */
185 if (!containsFullLinuxPackage(swocInfo)) {
186 usb_stor_dbg(us, "SWIMS: Switching to Modem Mode\n");
187 result = sierra_set_ms_mode(udev,
188 SWIMS_SET_MODE_Modem);
189 if (result < 0)
190 usb_stor_dbg(us, "SWIMS: Failed to switch modem\n");
191 kfree(swocInfo);
192 return -EIO;
193 }
194 kfree(swocInfo);
195 }
196 complete:
197 result = device_create_file(&us->pusb_intf->dev, &dev_attr_truinst);
198 if (result) {
> 199 kfree(swocInfo);
200 return result;
201 }
202
203 return 0;
204 }
205
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
device_create_file() could fail and return an error code. The fix
captures the error and returns the error code upstream in case it
indeed failed.
Signed-off-by: Kangjie Lu <[email protected]>
---
drivers/usb/storage/sierra_ms.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/usb/storage/sierra_ms.c b/drivers/usb/storage/sierra_ms.c
index 6ac60abd2e15..e605cbc3d8bf 100644
--- a/drivers/usb/storage/sierra_ms.c
+++ b/drivers/usb/storage/sierra_ms.c
@@ -194,8 +194,6 @@ int sierra_ms_init(struct us_data *us)
kfree(swocInfo);
}
complete:
- result = device_create_file(&us->pusb_intf->dev, &dev_attr_truinst);
-
- return 0;
+ return device_create_file(&us->pusb_intf->dev, &dev_attr_truinst);
}
--
2.17.1
On Sun, 24 Mar 2019, Kangjie Lu wrote:
> device_create_file() could fail and return an error code. The fix
> captures the error and returns the error code upstream in case it
> indeed failed.
>
> Signed-off-by: Kangjie Lu <[email protected]>
> ---
> drivers/usb/storage/sierra_ms.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/usb/storage/sierra_ms.c b/drivers/usb/storage/sierra_ms.c
> index 6ac60abd2e15..e605cbc3d8bf 100644
> --- a/drivers/usb/storage/sierra_ms.c
> +++ b/drivers/usb/storage/sierra_ms.c
> @@ -194,8 +194,6 @@ int sierra_ms_init(struct us_data *us)
> kfree(swocInfo);
> }
> complete:
> - result = device_create_file(&us->pusb_intf->dev, &dev_attr_truinst);
> -
> - return 0;
> + return device_create_file(&us->pusb_intf->dev, &dev_attr_truinst);
> }
Acked-by: Alan Stern <[email protected]>
It's possible the original author intended the function to succeed even
if device_create_file() failed, since the information in the file
doesn't seem to be very important. However, I will accept the patch.
Alan Stern
Hi Kangjie,
Thank you for the patch! Perhaps something to improve:
url: https://github.com/0day-ci/linux/commits/Kangjie-Lu/usb-sierra-fix-a-missing-check-of-device_create_file/20190325-101328
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
smatch warnings:
drivers/usb/storage/sierra_ms.c:199 sierra_ms_init() error: double free of 'swocInfo'
# https://github.com/0day-ci/linux/commit/04d66f3d072c3d14308aebecdbc0f2983ce443d2
git remote add linux-review https://github.com/0day-ci/linux
git remote update linux-review
git checkout 04d66f3d072c3d14308aebecdbc0f2983ce443d2
vim +/swocInfo +199 drivers/usb/storage/sierra_ms.c
32fe5e393 Kevin Lloyd 2008-07-10 126
32fe5e393 Kevin Lloyd 2008-07-10 127 int sierra_ms_init(struct us_data *us)
32fe5e393 Kevin Lloyd 2008-07-10 128 {
32fe5e393 Kevin Lloyd 2008-07-10 129 int result, retries;
32fe5e393 Kevin Lloyd 2008-07-10 130 struct swoc_info *swocInfo;
32fe5e393 Kevin Lloyd 2008-07-10 131 struct usb_device *udev;
32fe5e393 Kevin Lloyd 2008-07-10 132 struct Scsi_Host *sh;
32fe5e393 Kevin Lloyd 2008-07-10 133
32fe5e393 Kevin Lloyd 2008-07-10 134 retries = 3;
32fe5e393 Kevin Lloyd 2008-07-10 135 result = 0;
32fe5e393 Kevin Lloyd 2008-07-10 136 udev = us->pusb_dev;
32fe5e393 Kevin Lloyd 2008-07-10 137
32fe5e393 Kevin Lloyd 2008-07-10 138 sh = us_to_host(us);
0220a3f01 Alan Cox 2012-09-19 139 scsi_get_host_dev(sh);
32fe5e393 Kevin Lloyd 2008-07-10 140
32fe5e393 Kevin Lloyd 2008-07-10 141 /* Force Modem mode */
32fe5e393 Kevin Lloyd 2008-07-10 142 if (swi_tru_install == TRU_FORCE_MODEM) {
191648d03 Joe Perches 2013-04-19 143 usb_stor_dbg(us, "SWIMS: Forcing Modem Mode\n");
32fe5e393 Kevin Lloyd 2008-07-10 144 result = sierra_set_ms_mode(udev, SWIMS_SET_MODE_Modem);
32fe5e393 Kevin Lloyd 2008-07-10 145 if (result < 0)
191648d03 Joe Perches 2013-04-19 146 usb_stor_dbg(us, "SWIMS: Failed to switch to modem mode\n");
32fe5e393 Kevin Lloyd 2008-07-10 147 return -EIO;
32fe5e393 Kevin Lloyd 2008-07-10 148 }
32fe5e393 Kevin Lloyd 2008-07-10 149 /* Force Mass Storage mode (keep CD-Rom) */
32fe5e393 Kevin Lloyd 2008-07-10 150 else if (swi_tru_install == TRU_FORCE_MS) {
191648d03 Joe Perches 2013-04-19 151 usb_stor_dbg(us, "SWIMS: Forcing Mass Storage Mode\n");
32fe5e393 Kevin Lloyd 2008-07-10 152 goto complete;
32fe5e393 Kevin Lloyd 2008-07-10 153 }
32fe5e393 Kevin Lloyd 2008-07-10 154 /* Normal TRU-Install Logic */
32fe5e393 Kevin Lloyd 2008-07-10 155 else {
191648d03 Joe Perches 2013-04-19 156 usb_stor_dbg(us, "SWIMS: Normal SWoC Logic\n");
32fe5e393 Kevin Lloyd 2008-07-10 157
32fe5e393 Kevin Lloyd 2008-07-10 158 swocInfo = kmalloc(sizeof(struct swoc_info),
32fe5e393 Kevin Lloyd 2008-07-10 159 GFP_KERNEL);
191648d03 Joe Perches 2013-04-19 160 if (!swocInfo)
32fe5e393 Kevin Lloyd 2008-07-10 161 return -ENOMEM;
32fe5e393 Kevin Lloyd 2008-07-10 162
32fe5e393 Kevin Lloyd 2008-07-10 163 retries = 3;
32fe5e393 Kevin Lloyd 2008-07-10 164 do {
32fe5e393 Kevin Lloyd 2008-07-10 165 retries--;
32fe5e393 Kevin Lloyd 2008-07-10 166 result = sierra_get_swoc_info(udev, swocInfo);
32fe5e393 Kevin Lloyd 2008-07-10 167 if (result < 0) {
191648d03 Joe Perches 2013-04-19 168 usb_stor_dbg(us, "SWIMS: Failed SWoC query\n");
32fe5e393 Kevin Lloyd 2008-07-10 169 schedule_timeout_uninterruptible(2*HZ);
32fe5e393 Kevin Lloyd 2008-07-10 170 }
32fe5e393 Kevin Lloyd 2008-07-10 171 } while (retries && result < 0);
32fe5e393 Kevin Lloyd 2008-07-10 172
32fe5e393 Kevin Lloyd 2008-07-10 173 if (result < 0) {
191648d03 Joe Perches 2013-04-19 174 usb_stor_dbg(us, "SWIMS: Completely failed SWoC query\n");
32fe5e393 Kevin Lloyd 2008-07-10 175 kfree(swocInfo);
32fe5e393 Kevin Lloyd 2008-07-10 176 return -EIO;
32fe5e393 Kevin Lloyd 2008-07-10 177 }
32fe5e393 Kevin Lloyd 2008-07-10 178
191648d03 Joe Perches 2013-04-19 179 debug_swoc(&us->pusb_dev->dev, swocInfo);
32fe5e393 Kevin Lloyd 2008-07-10 180
f0183a338 Felipe Balbi 2016-04-18 181 /*
f0183a338 Felipe Balbi 2016-04-18 182 * If there is not Linux software on the TRU-Install device
32fe5e393 Kevin Lloyd 2008-07-10 183 * then switch to modem mode
32fe5e393 Kevin Lloyd 2008-07-10 184 */
32fe5e393 Kevin Lloyd 2008-07-10 185 if (!containsFullLinuxPackage(swocInfo)) {
191648d03 Joe Perches 2013-04-19 186 usb_stor_dbg(us, "SWIMS: Switching to Modem Mode\n");
32fe5e393 Kevin Lloyd 2008-07-10 187 result = sierra_set_ms_mode(udev,
32fe5e393 Kevin Lloyd 2008-07-10 188 SWIMS_SET_MODE_Modem);
32fe5e393 Kevin Lloyd 2008-07-10 189 if (result < 0)
191648d03 Joe Perches 2013-04-19 190 usb_stor_dbg(us, "SWIMS: Failed to switch modem\n");
32fe5e393 Kevin Lloyd 2008-07-10 191 kfree(swocInfo);
32fe5e393 Kevin Lloyd 2008-07-10 192 return -EIO;
32fe5e393 Kevin Lloyd 2008-07-10 193 }
32fe5e393 Kevin Lloyd 2008-07-10 194 kfree(swocInfo);
^^^^^^^^^^^^^^^^
32fe5e393 Kevin Lloyd 2008-07-10 195 }
break statement?
32fe5e393 Kevin Lloyd 2008-07-10 196 complete:
32fe5e393 Kevin Lloyd 2008-07-10 197 result = device_create_file(&us->pusb_intf->dev, &dev_attr_truinst);
04d66f3d0 Kangjie Lu 2019-03-24 198 if (result) {
04d66f3d0 Kangjie Lu 2019-03-24 @199 kfree(swocInfo);
^^^^^^^^^^^^^^^
Double free.
04d66f3d0 Kangjie Lu 2019-03-24 200 return result;
04d66f3d0 Kangjie Lu 2019-03-24 201 }
32fe5e393 Kevin Lloyd 2008-07-10 202
be475d902 Alan Stern 2009-05-21 203 return 0;
32fe5e393 Kevin Lloyd 2008-07-10 204 }
32fe5e393 Kevin Lloyd 2008-07-10 205
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
On Tue, Mar 26, 2019 at 11:18:31AM +0300, Dan Carpenter wrote:
> 32fe5e393 Kevin Lloyd 2008-07-10 193 }
> 32fe5e393 Kevin Lloyd 2008-07-10 194 kfree(swocInfo);
> ^^^^^^^^^^^^^^^^
>
> 32fe5e393 Kevin Lloyd 2008-07-10 195 }
>
> break statement?
Sorry, for some reason I saw "complete:" and read "default:". :/
But the warning seems valid.
regards,
dan carpenter
>
> 32fe5e393 Kevin Lloyd 2008-07-10 196 complete:
> 32fe5e393 Kevin Lloyd 2008-07-10 197 result = device_create_file(&us->pusb_intf->dev, &dev_attr_truinst);
> 04d66f3d0 Kangjie Lu 2019-03-24 198 if (result) {
> 04d66f3d0 Kangjie Lu 2019-03-24 @199 kfree(swocInfo);
> ^^^^^^^^^^^^^^^
> Double free.
>