Commit 3577afb0 authored Dec 09, 2020 by Jim Cromie Committed by Greg Kroah-Hartman Dec 09, 2020

dyndbg: fix use before null check



In commit a2d375ed ("dyndbg: refine export, rename to
dynamic_debug_exec_queries()"), a string is copied before checking it
isn't NULL.  Fix this, report a usage/interface error, and return the
proper error code.

Fixes: a2d375ed ("dyndbg: refine export, rename to dynamic_debug_exec_queries()")
Cc: stable@vger.kernel.org
--
-v2 drop comment tweak, improve commit message

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20201209183625.2432329-1-jim.cromie@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 0b81144a

lib/dynamic_debug.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -561,9 +561,14 @@ static int ddebug_exec_queries(char query, const char modname)
		int dynamic_debug_exec_queries(const char query, const char modname)
		{
		int rc;
		char *qry = kstrndup(query, PAGE_SIZE, GFP_KERNEL);
		char qry; / writable copy of query */

		if (!query)
		if (!query) {
		pr_err("non-null query/command string expected\n");
		return -EINVAL;
		}
		qry = kstrndup(query, PAGE_SIZE, GFP_KERNEL);
		if (!qry)
		return -ENOMEM;

		rc = ddebug_exec_queries(qry, modname);

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