From:   Thomas Zimmermann <tzimmermann@suse.de>
To:     deller@gmx.de, geert+renesas@glider.be, timur@kernel.org,
        rdunlap@infradead.org, paulus@samba.org, benh@kernel.crashing.org,
        linux@armlinux.org.uk, pjones@redhat.com, adaplas@gmail.com,
        s.hauer@pengutronix.de, shawnguo@kernel.org, mbroemme@libmpq.org,
        thomas@winischhofer.net, James.Bottomley@HansenPartnership.com,
        sudipm.mukherjee@gmail.com, teddy.wang@siliconmotion.com,
        corbet@lwn.net
Cc:     linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org,
        Thomas Zimmermann <tzimmermann@suse.de>
Subject: [PATCH v2 041/101] fbdev/kyrofb: Duplicate video-mode option string
Date:   Thu,  9 Mar 2023 17:01:01 +0100
Message-Id: <20230309160201.5163-42-tzimmermann@suse.de>
In-Reply-To: <20230309160201.5163-1-tzimmermann@suse.de>
References: <20230309160201.5163-1-tzimmermann@suse.de>
MIME-Version: 1.0
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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@suse.de>
---
 drivers/video/fbdev/kyro/fbdev.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/kyro/fbdev.c b/drivers/video/fbdev/kyro/fbdev.c
index 0596573ef140..97f4d8995e36 100644
--- a/drivers/video/fbdev/kyro/fbdev.c
+++ b/drivers/video/fbdev/kyro/fbdev.c
@@ -79,6 +79,7 @@ typedef struct {
 /* global graphics card info structure (one per card) */
 static device_info_t deviceInfo;
 
+static char *mode_option_buf;
 static char *mode_option = NULL;
 static int nopan = 0;
 static int nowrap = 1;
@@ -579,7 +580,9 @@ static int __init kyrofb_setup(char *options)
 		} else if (strcmp(this_opt, "nomtrr") == 0) {
 			nomtrr = 1;
 		} else {
-			mode_option = this_opt;
+			kfree(mode_option_buf);
+			mode_option_buf = kstrdup(this_opt, GFP_KERNEL); // ignore errors
+			mode_option = mode_option_buf;
 		}
 	}
 
@@ -805,6 +808,7 @@ static int __init kyrofb_init(void)
 static void __exit kyrofb_exit(void)
 {
 	pci_unregister_driver(&kyrofb_pci_driver);
+	kfree(mode_option_buf);
 }
 
 module_init(kyrofb_init);
-- 
2.39.2