console: Fix console name size mismatch

commit 6ae9200 ("enlarge console.name") increased the storage for the console name to 16 bytes, but not the corresponding struct console_cmdline::name storage. Console names longer than 8 bytes cause read beyond end-of-string and failure to match console; I'm not sure if there are other unexpected consequences. Cc: <[email protected]> # 2.6.22+ Signed-off-by: Peter Hurley <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
SKAPUSTIANSKYI · Mar 7, 2015 · 30a22c2 · 30a22c2
1 parent f0bf0bd
commit 30a22c2
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Showing 2 changed files with 2 additions and 1 deletion.
diff --git a/kernel/printk/console_cmdline.h b/kernel/printk/console_cmdline.h
@@ -3,7 +3,7 @@
 
 struct console_cmdline
 {
-	char	name[8];			/* Name of the driver	    */
+	char	name[16];			/* Name of the driver	    */
 	int	index;				/* Minor dev. to use	    */
 	char	*options;			/* Options for the driver   */
 #ifdef CONFIG_A11Y_BRAILLE_CONSOLE

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
@@ -2464,6 +2464,7 @@ void register_console(struct console *newcon)
 	for (i = 0, c = console_cmdline;
 	     i < MAX_CMDLINECONSOLES && c->name[0];
 	     i++, c++) {
+		BUILD_BUG_ON(sizeof(c->name) != sizeof(newcon->name));
 		if (strcmp(c->name, newcon->name) != 0)
 			continue;
 		if (newcon->index >= 0 &&