[PATCH v2 068/101] fbdev/s3fb: Duplicate video-mode option string

From: Thomas Zimmermann
Date: Thu Mar 09 2023 - 11:08:38 EST


Assume that the driver does not own the option string or its substrings
and hence duplicate the option string for the video mode. Allocate the
copy's memory with kstrdup() and free it in the module's exit function.

Done in preparation of switching the driver to struct option_iter and
constifying the option string.

v2:
* replace static memory with kstrdup()/kfree() (Geert)

Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
drivers/video/fbdev/s3fb.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/s3fb.c b/drivers/video/fbdev/s3fb.c
index 7d257489edcc..6bcedcde8aad 100644
--- a/drivers/video/fbdev/s3fb.c
+++ b/drivers/video/fbdev/s3fb.c
@@ -150,6 +150,7 @@ static const struct svga_timing_regs s3_timing_regs = {
/* Module parameters */


+static char *mode_option_buf;
static char *mode_option;
static int mtrr = 1;
static int fasttext = 1;
@@ -1535,8 +1536,11 @@ static int __init s3fb_setup(char *options)
mtrr = simple_strtoul(opt + 5, NULL, 0);
else if (!strncmp(opt, "fasttext:", 9))
fasttext = simple_strtoul(opt + 9, NULL, 0);
- else
- mode_option = opt;
+ else {
+ kfree(mode_option_buf);
+ mode_option_buf = kstrdup(opt, GFP_KERNEL); // ignore errors
+ mode_option = mode_option_buf;
+ }
}

return 0;
@@ -1549,6 +1553,7 @@ static void __exit s3fb_cleanup(void)
{
pr_debug("s3fb: cleaning up\n");
pci_unregister_driver(&s3fb_pci_driver);
+ kfree(mode_option_buf);
}

/* Driver Initialisation */
--
2.39.2