diff mbox series

[97/99] fbdev/vt8623fb: Duplicate video-mode option string

Message ID 20230306160016.4459-98-tzimmermann@suse.de
State New
Headers
Series fbdev: Fix memory leak in option parsing |

Commit Message

Thomas Zimmermann March 6, 2023, 4 p.m. UTC 
  Assume that the driver does not own the option string or its substrings
and hence duplicate the option string for the video mode. The driver only
parses the option string once as part of module initialization, so use
a static buffer to store the duplicated mode option. Linux automatically
frees the memory upon releasing the module.

Done in preparation of constifying the option string.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/video/fbdev/vt8623fb.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

Comments

kernel test robot March 7, 2023, 12:26 a.m. UTC | #1 
Hi Thomas,

I love your patch! Yet something to improve:

[auto build test ERROR on drm-misc/drm-misc-next]
[cannot apply to deller-parisc/for-next staging/staging-testing staging/staging-next staging/staging-linus linus/master v6.3-rc1 next-20230306]
[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/Thomas-Zimmermann/lib-Add-option-iterator/20230307-000524
base:   git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:    https://lore.kernel.org/r/20230306160016.4459-98-tzimmermann%40suse.de
patch subject: [PATCH 97/99] fbdev/vt8623fb: Duplicate video-mode option string
config: x86_64-randconfig-a016-20230306 (https://download.01.org/0day-ci/archive/20230307/202303070859.8Y5URjpT-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/819a7fd9e1404efc4f2140bcb4c7e39643b7e4ab
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Thomas-Zimmermann/lib-Add-option-iterator/20230307-000524
        git checkout 819a7fd9e1404efc4f2140bcb4c7e39643b7e4ab
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202303070859.8Y5URjpT-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/video/fbdev/vt8623fb.c:938:4: error: 'break' statement not in loop or switch statement
                           break;
                           ^
   drivers/video/fbdev/vt8623fb.c:940:4: error: 'break' statement not in loop or switch statement
                           break;
                           ^
   2 errors generated.


vim +/break +938 drivers/video/fbdev/vt8623fb.c

   924	
   925		if (fb_modesetting_disabled("vt8623fb"))
   926			return -ENODEV;
   927	
   928	#ifndef MODULE
   929		if (fb_get_options("vt8623fb", &option))
   930			return -ENODEV;
   931	
   932		if (option && *option) {
   933			static char mode_option_buf[256];
   934			int ret;
   935	
   936			ret = snprintf(mode_option_buf, sizeof(mode_option_buf), "%s", option);
   937			if (WARN(ret < 0, "vt8623fb: ignoring invalid option, ret=%d\n", ret))
 > 938				break;
   939			if (WARN(ret >= sizeof(mode_option_buf), "vt8623fb: option too long\n"))
   940				break;
   941			mode_option = mode_option_buf;
   942		}
   943	#endif
   944	
   945		pr_debug("vt8623fb: initializing\n");
   946		return pci_register_driver(&vt8623fb_pci_driver);
   947	}
   948
diff mbox series

Patch

diff --git a/drivers/video/fbdev/vt8623fb.c b/drivers/video/fbdev/vt8623fb.c
index 034333ee6e45..cbdca42d1708 100644
--- a/drivers/video/fbdev/vt8623fb.c
+++ b/drivers/video/fbdev/vt8623fb.c
@@ -929,8 +929,17 @@  static int __init vt8623fb_init(void)
 	if (fb_get_options("vt8623fb", &option))
 		return -ENODEV;
 
-	if (option && *option)
-		mode_option = option;
+	if (option && *option) {
+		static char mode_option_buf[256];
+		int ret;
+
+		ret = snprintf(mode_option_buf, sizeof(mode_option_buf), "%s", option);
+		if (WARN(ret < 0, "vt8623fb: ignoring invalid option, ret=%d\n", ret))
+			break;
+		if (WARN(ret >= sizeof(mode_option_buf), "vt8623fb: option too long\n"))
+			break;
+		mode_option = mode_option_buf;
+	}
 #endif
 
 	pr_debug("vt8623fb: initializing\n");