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 066/101] fbdev/rivafb: Duplicate video-mode option string
Date:   Thu,  9 Mar 2023 17:01:26 +0100
Message-Id: <20230309160201.5163-67-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/riva/fbdev.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/riva/fbdev.c b/drivers/video/fbdev/riva/fbdev.c
index 41edc6e79460..8a7dc7452938 100644
--- a/drivers/video/fbdev/riva/fbdev.c
+++ b/drivers/video/fbdev/riva/fbdev.c
@@ -205,6 +205,7 @@ static bool noaccel  = 0;
 static bool nomtrr = 0;
 static int backlight = IS_BUILTIN(CONFIG_PMAC_BACKLIGHT);
 
+static char *mode_option_buf;
 static char *mode_option = NULL;
 static bool strictmode       = 0;
 
@@ -2132,8 +2133,11 @@ static int rivafb_setup(char *options)
 			strictmode = 1;
 		} else if (!strncmp(this_opt, "noaccel", 7)) {
 			noaccel = 1;
-		} else
-			mode_option = this_opt;
+		} else {
+			kfree(mode_option_buf);
+			mode_option_buf = kstrdup(this_opt, GFP_KERNEL); // ignore errors
+			mode_option = mode_option_buf;
+		}
 	}
 	NVTRACE_LEAVE();
 	return 0;
@@ -2178,6 +2182,7 @@ module_init(rivafb_init);
 static void __exit rivafb_exit(void)
 {
 	pci_unregister_driver(&rivafb_driver);
+	kfree(mode_option_buf);
 }
 
 module_exit(rivafb_exit);
-- 
2.39.2