From: Zack Rusin zackr@vmware.com
Make sure vmmouse_data::phys can hold serio::phys (which is 32 bytes) plus an extra string, extend it to 64.
Fixes gcc13 warnings: drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’: drivers/input/mouse/vmmouse.c:455:53: warning: ‘/input1’ directive output may be truncated writing 7 bytes into a region of size between 1 and 32 [-Wformat-truncation=] 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~ drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a destination of size 32 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 456 | psmouse->ps2dev.serio->phys); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Zack Rusin zackr@vmware.com Fixes: 8b8be51b4fd3 ("Input: add vmmouse driver") Cc: Dmitry Torokhov dmitry.torokhov@gmail.com Cc: VMware Graphics Reviewers linux-graphics-maintainer@vmware.com Cc: Arnd Bergmann arnd@arndb.de Cc: Robert Jarzmik robert.jarzmik@free.fr Cc: Raul Rangel rrangel@chromium.org Cc: linux-input@vger.kernel.org Cc: stable@vger.kernel.org # v4.1+ --- drivers/input/mouse/vmmouse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/input/mouse/vmmouse.c b/drivers/input/mouse/vmmouse.c index ea9eff7c8099..7248cada4c8c 100644 --- a/drivers/input/mouse/vmmouse.c +++ b/drivers/input/mouse/vmmouse.c @@ -72,7 +72,7 @@ */ struct vmmouse_data { struct input_dev *abs_dev; - char phys[32]; + char phys[64]; char dev_name[128]; };
Zack,
On Mon, Nov 27, 2023 at 03:42:06PM -0500, Zack Rusin wrote:
From: Zack Rusin zackr@vmware.com
Make sure vmmouse_data::phys can hold serio::phys (which is 32 bytes) plus an extra string, extend it to 64.
Fixes gcc13 warnings: drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’: drivers/input/mouse/vmmouse.c:455:53: warning: ‘/input1’ directive output may be truncated writing 7 bytes into a region of size between 1 and 32 [-Wformat-truncation=] 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~ drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a destination of size 32 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 456 | psmouse->ps2dev.serio->phys); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Zack Rusin zackr@vmware.com Fixes: 8b8be51b4fd3 ("Input: add vmmouse driver") Cc: Dmitry Torokhov dmitry.torokhov@gmail.com Cc: VMware Graphics Reviewers linux-graphics-maintainer@vmware.com Cc: Arnd Bergmann arnd@arndb.de Cc: Robert Jarzmik robert.jarzmik@free.fr Cc: Raul Rangel rrangel@chromium.org Cc: linux-input@vger.kernel.org Cc: stable@vger.kernel.org # v4.1+
drivers/input/mouse/vmmouse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/input/mouse/vmmouse.c b/drivers/input/mouse/vmmouse.c index ea9eff7c8099..7248cada4c8c 100644 --- a/drivers/input/mouse/vmmouse.c +++ b/drivers/input/mouse/vmmouse.c @@ -72,7 +72,7 @@ */ struct vmmouse_data { struct input_dev *abs_dev;
- char phys[32];
- char phys[64];
This simply wastes 32 bytes. It is perfectly fine to truncate phys (which does not happen in real life).
-Wformat-truncation is disabled in normal builds, folks should stop using it with W=1 as well.
Thanks.
On Sun, Dec 3, 2023, at 19:41, Dmitry Torokhov wrote:
On Mon, Nov 27, 2023 at 03:42:06PM -0500, Zack Rusin wrote:
From: Zack Rusin zackr@vmware.com
Make sure vmmouse_data::phys can hold serio::phys (which is 32 bytes) plus an extra string, extend it to 64.
Fixes gcc13 warnings: drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’: drivers/input/mouse/vmmouse.c:455:53: warning: ‘/input1’ directive output may be truncated writing 7 bytes into a region of size between 1 and 32 [-Wformat-truncation=] 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~ drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a destination of size 32 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 456 | psmouse->ps2dev.serio->phys); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This simply wastes 32 bytes. It is perfectly fine to truncate phys (which does not happen in real life).
-Wformat-truncation is disabled in normal builds, folks should stop using it with W=1 as well.
It does find real bugs, and we are fairly close to being able to enable it by default once the remaining warnings are all fixed.
It also doesn't waste any memory in this specific case since vmmouse_data is currently at 168 bytes, which gets rounded up to either 192 or 256 bytes anyway. I'd suggest using the minimum size that is large enough though, in this case 39 bytes for the string I guess.
Arnd
From: Arnd Bergmann
Sent: 03 December 2023 20:51 On Sun, Dec 3, 2023, at 19:41, Dmitry Torokhov wrote:
On Mon, Nov 27, 2023 at 03:42:06PM -0500, Zack Rusin wrote:
From: Zack Rusin zackr@vmware.com
Make sure vmmouse_data::phys can hold serio::phys (which is 32 bytes) plus an extra string, extend it to 64.
Fixes gcc13 warnings: drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’: drivers/input/mouse/vmmouse.c:455:53: warning: ‘/input1’ directive output may be truncated writing
7 bytes into a region of size between 1 and 32 [-Wformat-truncation=]
455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~ drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a
destination of size 32
455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 456 | psmouse->ps2dev.serio->phys); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This simply wastes 32 bytes. It is perfectly fine to truncate phys (which does not happen in real life).
-Wformat-truncation is disabled in normal builds, folks should stop using it with W=1 as well.
It does find real bugs, and we are fairly close to being able to enable it by default once the remaining warnings are all fixed.
It also doesn't waste any memory in this specific case since vmmouse_data is currently at 168 bytes, which gets rounded up to either 192 or 256 bytes anyway. I'd suggest using the minimum size that is large enough though, in this case 39 bytes for the string I guess.
That rather depends on whether any of the earlier char[] lengths have been rounded up to a 'nice' value.
I'd also have thought that dangerous overflows would come from unbounded %s formats, not fixed size strings or integers that are always small.
There really ought to be a sane method of telling gcc not to bleat about snprintf() potentially overflowing the target.
I've tried a few thing but none of them work. IIRC using the result (in some ways) is enough, but neither (void)snprintf(...); or if (snprintf(...)); is enough (but they 'fix' 'warn unused result').
David
Arnd
- Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
On Sun, Dec 03, 2023 at 09:14:49PM +0000, David Laight wrote:
From: Arnd Bergmann
Sent: 03 December 2023 20:51 On Sun, Dec 3, 2023, at 19:41, Dmitry Torokhov wrote:
On Mon, Nov 27, 2023 at 03:42:06PM -0500, Zack Rusin wrote:
From: Zack Rusin zackr@vmware.com
Make sure vmmouse_data::phys can hold serio::phys (which is 32 bytes) plus an extra string, extend it to 64.
Fixes gcc13 warnings: drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’: drivers/input/mouse/vmmouse.c:455:53: warning: ‘/input1’ directive output may be truncated writing
7 bytes into a region of size between 1 and 32 [-Wformat-truncation=]
455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~ drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a
destination of size 32
455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 456 | psmouse->ps2dev.serio->phys); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This simply wastes 32 bytes. It is perfectly fine to truncate phys (which does not happen in real life).
-Wformat-truncation is disabled in normal builds, folks should stop using it with W=1 as well.
It does find real bugs, and we are fairly close to being able to enable it by default once the remaining warnings are all fixed.
It also doesn't waste any memory
... at this time ...
in this specific case since vmmouse_data is currently at 168 bytes, which gets rounded up to either 192 or 256 bytes anyway. I'd suggest using the minimum size that is large enough though, in this case 39 bytes for the string I guess.
This assumes we never change how our allocators work to provide better memory packing.
That rather depends on whether any of the earlier char[] lengths have been rounded up to a 'nice' value.
I'd also have thought that dangerous overflows would come from unbounded %s formats, not fixed size strings or integers that are always small.
There really ought to be a sane method of telling gcc not to bleat about snprintf() potentially overflowing the target.
Yes, that would be my preference before we enable this warning globally.
Thanks.
Make sure vmmouse_data::phys can hold serio::phys (which is 32 bytes) plus an extra string, extend it to 64.
Fixes gcc13 warnings: drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’: drivers/input/mouse/vmmouse.c:455:53: warning: ‘/input1’ directive output may be truncated writing 7 bytes into a region of size between 1 and 32 [-Wformat-truncation=] 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~ drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a destination of size 32 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 456 | psmouse->ps2dev.serio->phys); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
v2: Use the exact size for the vmmouse_data::phys
Signed-off-by: Zack Rusin zack.rusin@broadcom.com Fixes: 8b8be51b4fd3 ("Input: add vmmouse driver") Cc: Dmitry Torokhov dmitry.torokhov@gmail.com Cc: Arnd Bergmann arnd@arndb.de Cc: Robert Jarzmik robert.jarzmik@free.fr Cc: Raul Rangel rrangel@chromium.org Cc: linux-input@vger.kernel.org Cc: stable@vger.kernel.org # v4.1+ --- drivers/input/mouse/vmmouse.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/input/mouse/vmmouse.c b/drivers/input/mouse/vmmouse.c index ea9eff7c8099..74131673e2f3 100644 --- a/drivers/input/mouse/vmmouse.c +++ b/drivers/input/mouse/vmmouse.c @@ -63,6 +63,8 @@ #define VMMOUSE_VENDOR "VMware" #define VMMOUSE_NAME "VMMouse"
+#define VMMOUSE_PHYS_NAME_POSTFIX_STR "/input1" + /** * struct vmmouse_data - private data structure for the vmmouse driver * @@ -72,7 +74,8 @@ */ struct vmmouse_data { struct input_dev *abs_dev; - char phys[32]; + char phys[sizeof_field(struct serio, phys) + + strlen(VMMOUSE_PHYS_NAME_POSTFIX_STR)]; char dev_name[128]; };
@@ -452,7 +455,8 @@ int vmmouse_init(struct psmouse *psmouse) psmouse->private = priv;
/* Set up and register absolute device */ - snprintf(priv->phys, sizeof(priv->phys), "%s/input1", + snprintf(priv->phys, sizeof(priv->phys), + "%s" VMMOUSE_PHYS_NAME_POSTFIX_STR, psmouse->ps2dev.serio->phys);
/* Mimic name setup for relative device in psmouse-base.c */
On Thu, Jan 4, 2024 at 12:06 AM Zack Rusin zack.rusin@broadcom.com wrote:
Make sure vmmouse_data::phys can hold serio::phys (which is 32 bytes) plus an extra string, extend it to 64.
Fixes gcc13 warnings: drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’: drivers/input/mouse/vmmouse.c:455:53: warning: ‘/input1’ directive output may be truncated writing 7 bytes into a region of size between 1 and 32 [-Wformat-truncation=] 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~ drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a destination of size 32 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 456 | psmouse->ps2dev.serio->phys); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
v2: Use the exact size for the vmmouse_data::phys
Signed-off-by: Zack Rusin zack.rusin@broadcom.com Fixes: 8b8be51b4fd3 ("Input: add vmmouse driver") Cc: Dmitry Torokhov dmitry.torokhov@gmail.com Cc: Arnd Bergmann arnd@arndb.de Cc: Robert Jarzmik robert.jarzmik@free.fr Cc: Raul Rangel rrangel@chromium.org Cc: linux-input@vger.kernel.org Cc: stable@vger.kernel.org # v4.1+
drivers/input/mouse/vmmouse.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/input/mouse/vmmouse.c b/drivers/input/mouse/vmmouse.c index ea9eff7c8099..74131673e2f3 100644 --- a/drivers/input/mouse/vmmouse.c +++ b/drivers/input/mouse/vmmouse.c @@ -63,6 +63,8 @@ #define VMMOUSE_VENDOR "VMware" #define VMMOUSE_NAME "VMMouse"
+#define VMMOUSE_PHYS_NAME_POSTFIX_STR "/input1"
/**
- struct vmmouse_data - private data structure for the vmmouse driver
@@ -72,7 +74,8 @@ */ struct vmmouse_data { struct input_dev *abs_dev;
char phys[32];
char phys[sizeof_field(struct serio, phys) +strlen(VMMOUSE_PHYS_NAME_POSTFIX_STR)]; char dev_name[128];};
@@ -452,7 +455,8 @@ int vmmouse_init(struct psmouse *psmouse) psmouse->private = priv;
/* Set up and register absolute device */
snprintf(priv->phys, sizeof(priv->phys), "%s/input1",
snprintf(priv->phys, sizeof(priv->phys),"%s" VMMOUSE_PHYS_NAME_POSTFIX_STR, psmouse->ps2dev.serio->phys); /* Mimic name setup for relative device in psmouse-base.c */
Sorry, I missed the original discussion of this during the VMware->Broadcom email transition. How about we just use the exact sizing then like in the v2?
z
Hi Zack,
kernel test robot noticed the following build errors:
[auto build test ERROR on dtor-input/next] [also build test ERROR on dtor-input/for-linus linus/master v6.7-rc8 next-20240104] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Zack-Rusin/input-vmmouse-Fix-... base: https://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git next patch link: https://lore.kernel.org/r/20240104050605.1773158-1-zack.rusin%40broadcom.com patch subject: [PATCH v2] input/vmmouse: Fix device name copies config: i386-buildonly-randconfig-001-20240104 (https://download.01.org/0day-ci/archive/20240104/202401042305.WdnDeo57-lkp@i...) compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240104/202401042305.WdnDeo57-lkp@i...)
If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot lkp@intel.com | Closes: https://lore.kernel.org/oe-kbuild-all/202401042305.WdnDeo57-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/input/mouse/vmmouse.c:77:7: error: variably modified 'phys' at file scope
char phys[sizeof_field(struct serio, phys) + ^~~~
vim +/phys +77 drivers/input/mouse/vmmouse.c
67 68 /** 69 * struct vmmouse_data - private data structure for the vmmouse driver 70 * 71 * @abs_dev: "Absolute" device used to report absolute mouse movement. 72 * @phys: Physical path for the absolute device. 73 * @dev_name: Name attribute name for the absolute device. 74 */ 75 struct vmmouse_data { 76 struct input_dev *abs_dev;
77 char phys[sizeof_field(struct serio, phys) +
78 strlen(VMMOUSE_PHYS_NAME_POSTFIX_STR)]; 79 char dev_name[128]; 80 }; 81
On Thu, Jan 4, 2024 at 11:04 AM kernel test robot lkp@intel.com wrote:
Hi Zack,
kernel test robot noticed the following build errors:
[auto build test ERROR on dtor-input/next] [also build test ERROR on dtor-input/for-linus linus/master v6.7-rc8 next-20240104] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Zack-Rusin/input-vmmouse-Fix-... base: https://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git next patch link: https://lore.kernel.org/r/20240104050605.1773158-1-zack.rusin%40broadcom.com patch subject: [PATCH v2] input/vmmouse: Fix device name copies config: i386-buildonly-randconfig-001-20240104 (https://download.01.org/0day-ci/archive/20240104/202401042305.WdnDeo57-lkp@i...) compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240104/202401042305.WdnDeo57-lkp@i...)
If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot lkp@intel.com | Closes: https://lore.kernel.org/oe-kbuild-all/202401042305.WdnDeo57-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/input/mouse/vmmouse.c:77:7: error: variably modified 'phys' at file scope
char phys[sizeof_field(struct serio, phys) + ^~~~
This can be trivially fixed by using __builtin_strlen which with fortify-strings.h is used anyway but before respining this I'll wait to hear if this approach is ok. The sparse warning we can't do much about because it doesn't recognize the fact that the array size is a compile time expression.
z
Hi Zack,
kernel test robot noticed the following build warnings:
[auto build test WARNING on dtor-input/next] [also build test WARNING on dtor-input/for-linus linus/master v6.7-rc8 next-20240104] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Zack-Rusin/input-vmmouse-Fix-... base: https://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git next patch link: https://lore.kernel.org/r/20240104050605.1773158-1-zack.rusin%40broadcom.com patch subject: [PATCH v2] input/vmmouse: Fix device name copies config: i386-randconfig-061-20240104 (https://download.01.org/0day-ci/archive/20240105/202401050307.tWbIHuS1-lkp@i...) compiler: gcc-12 (Debian 12.2.0-14) 12.2.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240105/202401050307.tWbIHuS1-lkp@i...)
If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot lkp@intel.com | Closes: https://lore.kernel.org/oe-kbuild-all/202401050307.tWbIHuS1-lkp@intel.com/
sparse warnings: (new ones prefixed by >>)
drivers/input/mouse/vmmouse.c:77:52: sparse: sparse: Variable length array is used. drivers/input/mouse/vmmouse.c:77:14: sparse: sparse: flexible array member 'phys' is not last
vim +77 drivers/input/mouse/vmmouse.c
67 68 /** 69 * struct vmmouse_data - private data structure for the vmmouse driver 70 * 71 * @abs_dev: "Absolute" device used to report absolute mouse movement. 72 * @phys: Physical path for the absolute device. 73 * @dev_name: Name attribute name for the absolute device. 74 */ 75 struct vmmouse_data { 76 struct input_dev *abs_dev;
77 char phys[sizeof_field(struct serio, phys) +
78 strlen(VMMOUSE_PHYS_NAME_POSTFIX_STR)]; 79 char dev_name[128]; 80 }; 81
Hi Zack,
kernel test robot noticed the following build errors:
[auto build test ERROR on dtor-input/next] [also build test ERROR on dtor-input/for-linus linus/master v6.7-rc8 next-20240104] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Zack-Rusin/input-vmmouse-Fix-... base: https://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git next patch link: https://lore.kernel.org/r/20240104050605.1773158-1-zack.rusin%40broadcom.com patch subject: [PATCH v2] input/vmmouse: Fix device name copies config: i386-allmodconfig (https://download.01.org/0day-ci/archive/20240105/202401050506.N1aMF9sD-lkp@i...) compiler: ClangBuiltLinux clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240105/202401050506.N1aMF9sD-lkp@i...)
If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot lkp@intel.com | Closes: https://lore.kernel.org/oe-kbuild-all/202401050506.N1aMF9sD-lkp@intel.com/
All error/warnings (new ones prefixed by >>):
drivers/input/mouse/vmmouse.c:78:5: warning: variable length array used [-Wvla]
77 | char phys[sizeof_field(struct serio, phys) + | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 78 | strlen(VMMOUSE_PHYS_NAME_POSTFIX_STR)]; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/input/mouse/vmmouse.c:77:7: error: fields must have a constant size: 'variable length array in structure' extension will never be supported
77 | char phys[sizeof_field(struct serio, phys) + | ^ 1 warning and 1 error generated.
vim +77 drivers/input/mouse/vmmouse.c
67 68 /** 69 * struct vmmouse_data - private data structure for the vmmouse driver 70 * 71 * @abs_dev: "Absolute" device used to report absolute mouse movement. 72 * @phys: Physical path for the absolute device. 73 * @dev_name: Name attribute name for the absolute device. 74 */ 75 struct vmmouse_data { 76 struct input_dev *abs_dev;
77 char phys[sizeof_field(struct serio, phys) + 78 strlen(VMMOUSE_PHYS_NAME_POSTFIX_STR)];
79 char dev_name[128]; 80 }; 81
From: Zack Rusin
Sent: 04 January 2024 05:06
Make sure vmmouse_data::phys can hold serio::phys (which is 32 bytes) plus an extra string, extend it to 64.
Fixes gcc13 warnings: drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’: drivers/input/mouse/vmmouse.c:455:53: warning: ‘/input1’ directive output may be truncated writing 7 bytes into a region of size between 1 and 32 [-Wformat-truncation=] 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~ drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a destination of size 32 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 456 | psmouse->ps2dev.serio->phys); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
v2: Use the exact size for the vmmouse_data::phys
Signed-off-by: Zack Rusin zack.rusin@broadcom.com Fixes: 8b8be51b4fd3 ("Input: add vmmouse driver") Cc: Dmitry Torokhov dmitry.torokhov@gmail.com Cc: Arnd Bergmann arnd@arndb.de Cc: Robert Jarzmik robert.jarzmik@free.fr Cc: Raul Rangel rrangel@chromium.org Cc: linux-input@vger.kernel.org Cc: stable@vger.kernel.org # v4.1+
drivers/input/mouse/vmmouse.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/input/mouse/vmmouse.c b/drivers/input/mouse/vmmouse.c index ea9eff7c8099..74131673e2f3 100644 --- a/drivers/input/mouse/vmmouse.c +++ b/drivers/input/mouse/vmmouse.c @@ -63,6 +63,8 @@ #define VMMOUSE_VENDOR "VMware" #define VMMOUSE_NAME "VMMouse"
+#define VMMOUSE_PHYS_NAME_POSTFIX_STR "/input1"
/**
- struct vmmouse_data - private data structure for the vmmouse driver
@@ -72,7 +74,8 @@ */ struct vmmouse_data { struct input_dev *abs_dev;
- char phys[32];
- char phys[sizeof_field(struct serio, phys) +
strlen(VMMOUSE_PHYS_NAME_POSTFIX_STR)];};
@@ -452,7 +455,8 @@ int vmmouse_init(struct psmouse *psmouse) psmouse->private = priv;
/* Set up and register absolute device */
- snprintf(priv->phys, sizeof(priv->phys), "%s/input1",
- snprintf(priv->phys, sizeof(priv->phys),
"%s" VMMOUSE_PHYS_NAME_POSTFIX_STR,
Notwithstanding any error (fixed) or not from the gcc/build robert or sparse that 'fix' is entirely horrible.
Related I'm guessing that dev_name[128] is either likely to be truncated or massively far too long?
There are a few way to get gcc to STFU :-)
David
- Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
linux-stable-mirror@lists.linaro.org
-
Arnd Bergmann -
David Laight -
Dmitry Torokhov -
kernel test robot -
Zack Rusin -
Zack Rusin