Commit 0384c8ea authored by Ankit Khushwaha's avatar Ankit Khushwaha Committed by Andrew Morton
Browse files

selftests/mm/uffd: initialize char variable to Null 

In "uffd-stress.c" & "uffd-unit-tests.c". address of char variable having
garbage value (uninitialized) is passed to 'write' syscall triggers
warning.

	uffd-stress.c:246:39: warning: variable 'c' is uninitialized when
	passed  as a const pointer argument here
	[-Wuninitialized-const-pointer]

	uffd-unit-tests.c:581:31: warning: variable 'c' is uninitialized
	when passed as a const pointer argument here
	[-Wuninitialized-const-pointer]

so the fix is to assign char variable to '\0' to prevent writing of
garbage value.

Link: https://lkml.kernel.org/r/20251126160830.52124-1-ankitkhushwaha.linux@gmail.com


Signed-off-by: default avatarAnkit Khushwaha <ankitkhushwaha.linux@gmail.com>
Reviewed-by: default avatarMike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Bill Wendling <morbo@google.com>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent f65372cd

tools/testing/selftests/mm/uffd-stress.c

+1 −1
Original line number Diff line number Diff line
@@ -241,7 +241,7 @@ static int stress(struct uffd_args *args) 
			return 1;



	for (cpu = 0; cpu < gopts->nr_parallel; cpu++) {

		char c;

		char c = '\0';

		if (bounces & BOUNCE_POLL) {

			if (write(gopts->pipefd[cpu*2+1], &c, 1) != 1)

				err("pipefd write error");

tools/testing/selftests/mm/uffd-unit-tests.c

+4 −4
Original line number Diff line number Diff line
@@ -543,7 +543,7 @@ static void uffd_minor_test_common(uffd_global_test_opts_t *gopts, bool test_col 
{

	unsigned long p;

	pthread_t uffd_mon;

	char c;

	char c = '\0';

	struct uffd_args args = { 0 };

	args.gopts = gopts;
@@ -759,7 +759,7 @@ static void uffd_sigbus_test_common(uffd_global_test_opts_t *gopts, bool wp) 
	pthread_t uffd_mon;

	pid_t pid;

	int err;

	char c;

	char c = '\0';

	struct uffd_args args = { 0 };

	args.gopts = gopts;
@@ -819,7 +819,7 @@ static void uffd_events_test_common(uffd_global_test_opts_t *gopts, bool wp) 
	pthread_t uffd_mon;

	pid_t pid;

	int err;

	char c;

	char c = '\0';

	struct uffd_args args = { 0 };

	args.gopts = gopts;
@@ -1125,7 +1125,7 @@ uffd_move_test_common(uffd_global_test_opts_t *gopts, 
{

	unsigned long nr;

	pthread_t uffd_mon;

	char c;

	char c = '\0';

	unsigned long long count;

	struct uffd_args args = { 0 };

	char *orig_area_src = NULL, *orig_area_dst = NULL;