From: Shreyas Joshi shreyas.joshi@biamp.com
[ Upstream commit 48021f98130880dd74286459a1ef48b5e9bc374f ]
If uboot passes a blank string to console_setup then it results in a trashed memory. Ultimately, the kernel crashes during freeing up the memory.
This fix checks if there is a blank parameter being passed to console_setup from uboot. In case it detects that the console parameter is blank then it doesn't setup the serial device and it gracefully exits.
Link: https://lore.kernel.org/r/20200522065306.83-1-shreyas.joshi@biamp.com Signed-off-by: Shreyas Joshi shreyas.joshi@biamp.com Acked-by: Sergey Senozhatsky sergey.senozhatsky@gmail.com [pmladek@suse.com: Better format the commit message and code, remove unnecessary brackets.] Signed-off-by: Petr Mladek pmladek@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/printk/printk.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 4e50beb162c00..f96b22db5fe70 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2092,6 +2092,9 @@ static int __init console_setup(char *str) char *s, *options, *brl_options = NULL; int idx;
+ if (str[0] == 0) + return 1; + if (_braille_console_setup(&str, &brl_options)) return 1;