diff mbox series

[v2] input/vmmouse: Fix device name copies

Message ID 20240104050605.1773158-1-zack.rusin@broadcom.com
State New
Headers show
Series [v2] input/vmmouse: Fix device name copies | expand

Commit Message

Zack Rusin Jan. 4, 2024, 5:06 a.m. UTC
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(-)

Comments

Zack Rusin Jan. 4, 2024, 5:07 a.m. UTC | #1
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
kernel test robot Jan. 4, 2024, 7:23 p.m. UTC | #2
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-device-name-copies/20240104-130724
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@intel.com/config)
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@intel.com/reproduce)

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
kernel test robot Jan. 4, 2024, 10:01 p.m. UTC | #3
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-device-name-copies/20240104-130724
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@intel.com/config)
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@intel.com/reproduce)

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
David Laight Jan. 4, 2024, 10:57 p.m. UTC | #4
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)];
>  	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);

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)
diff mbox series

Patch

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 */