[PATCH 5.7 088/204] bootconfig: Fix to find the initargs correctly

Greg Kroah-Hartman
2020-08-20T13:06:35Z

From: Masami Hiramatsu <mhiramat@kernel.org>

commit 477d08478170469d10b533624342d13701e24b34 upstream.

Since the parse_args() stops parsing at '--', bootconfig_params()
will never get the '--' as param and initargs_found never be true.
In the result, if we pass some init arguments via the bootconfig,
those are always appended to the kernel command line with '--'
even if the kernel command line already has '--'.

To fix this correctly, check the return value of parse_args()
and set initargs_found true if the return value is not an error
but a valid address.

Link: https://lkml.kernel.org/r/159650953285.270383.14822353843556363851.stgit@devnote2

Fixes: f61872bb58a1 ("bootconfig: Use parse_args() to find bootconfig and '--'")
Cc: stable@vger.kernel.org
Reported-by: Arvind Sankar <nivedita@alum.mit.edu>
Suggested-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
init/main.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

--- a/init/main.c
+++ b/init/main.c
@@ -385,8 +385,6 @@ static int __init bootconfig_params(char
{
if (strcmp(param, "bootconfig") == 0) {
bootconfig_found = true;
- } else if (strcmp(param, "--") == 0) {
- initargs_found = true;
}
return 0;
}
@@ -397,19 +395,23 @@ static void __init setup_boot_config(con
const char *msg;
int pos;
u32 size, csum;
- char *data, *copy;
+ char *data, *copy, *err;
int ret;

/* Cut out the bootconfig data even if we have no bootconfig option */
data = get_boot_config_from_initrd(&size, &csum);

strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
- parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL,
- bootconfig_params);
+ err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL,
+ bootconfig_params);

- if (!bootconfig_found)
+ if (IS_ERR(err) || !bootconfig_found)
return;

+ /* parse_args() stops at '--' and returns an address */
+ if (err)
+ initargs_found = true;
+
if (!data) {
pr_err("'bootconfig' found on command line, but no bootconfig found\n");
return;