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Subject: Re: ac0e958a00:
 Kernel_panic-not_syncing:stack-protector:Kernel_stack_is_corrupted_in:run_init_process
To:     kernel test robot <oliver.sang@intel.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        0day robot <lkp@intel.com>, lkp@lists.01.org
References: <20201112071145.GC17067@xsang-OptiPlex-9020>
From:   Rob Landley <rob@landley.net>
Message-ID: <87765a0e-3a49-d437-4010-4848b8ece199@landley.net>
Date:   Thu, 12 Nov 2020 06:46:09 -0600
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On 11/12/20 1:11 AM, kernel test robot wrote:
> 
> Greeting,
> 
> FYI, we noticed the following commit (built with gcc-9):

Blah, switched from strlcpy to sprintf due to the lack of spaces and didn't
adjust the size.

(And yes, the compiler's lifetime analysis should free the stack space before
the tail call, and I'd assume exec restarts the stack anyway.)

Second-attempt-by: Rob Landley <rob@landley.net>
---

 init/main.c |   15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/init/main.c b/init/main.c
index 130376ec10ba..e92320816ef8 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1328,15 +1328,16 @@ static void __init do_pre_smp_initcalls(void)
 static int run_init_process(const char *init_filename)
 {
 	const char *const *p;
+	char buf[512], *s = buf;

 	argv_init[0] = init_filename;
-	pr_info("Run %s as init process\n", init_filename);
-	pr_debug("  with arguments:\n");
-	for (p = argv_init; *p; p++)
-		pr_debug("    %s\n", *p);
-	pr_debug("  with environment:\n");
-	for (p = envp_init; *p; p++)
-		pr_debug("    %s\n", *p);
+
+	for (p = (void *)envp_init; *p; p++)
+		s += sprintf(s, "%.*s ", (int)(sizeof(buf)-(s-buf)-2), *p);
+	for (p = (void *)argv_init; *p; p++)
+		s += sprintf(s, "%.*s ", (int)(sizeof(buf)-(s-buf)-2), *p);
+	pr_info("Run init: %s\n", buf);
+
 	return kernel_execve(init_filename, argv_init, envp_init);
 }