This is a note to let you know that I've just added the patch titled
printk: handle blank console arguments passed in.
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
printk-handle-blank-console-arguments-passed-in.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 702cec586f6ee210213b0a6ba629230b8b8af02c
Author: Shreyas Joshi <shreyas.joshi@xxxxxxxxx>
Date: Fri May 22 16:53:06 2020 +1000
printk: handle blank console arguments passed in.
[ 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@xxxxxxxxx
Signed-off-by: Shreyas Joshi <shreyas.joshi@xxxxxxxxx>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx>
[pmladek@xxxxxxxx: Better format the commit message and code, remove unnecessary brackets.]
Signed-off-by: Petr Mladek <pmladek@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 3cb0e5b479ff3..cf272aba362be 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -2148,6 +2148,9 @@ 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;
