In commit a2d375eda771 ("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: a2d375eda771 ("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 --- lib/dynamic_debug.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index bd7b3aaa93c3..c70d6347afa2 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -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);