Commit b78c522a authored Mar 05, 2019 by Marc-André Lureau Committed by Laurent Vivier Mar 07, 2019

linux-user: fix "may be used uninitialized" warnings



Fixes:

/home/elmarco/src/qemu/linux-user/syscall.c: In function ‘do_ioctl_rt’:
/home/elmarco/src/qemu/linux-user/syscall.c:4773:9: error: ‘host_rt_dev_ptr’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
     if (*host_rt_dev_ptr != 0) {
         ^~~~~~~~~~~~~~~~
/home/elmarco/src/qemu/linux-user/syscall.c:4774:9: error: ‘target_rt_dev_ptr’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
         unlock_user((void *)*host_rt_dev_ptr,
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                     *target_rt_dev_ptr, 0);
                     ~~~~~~~~~~~~~~~~~~~~~~

Based on previous discussion from patch "linux-users/syscall: make
do_ioctl_rt safer" by Alex Bennée.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20190305151500.25038-1-marcandre.lureau@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

parent ba584f1d

linux-user/syscall.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -4733,8 +4733,8 @@ static abi_long do_ioctl_rt(const IOCTLEntry ie, uint8_t buf_temp,
		const int dst_offsets, src_offsets;
		int target_size;
		void *argptr;
		abi_ulong *target_rt_dev_ptr;
		unsigned long *host_rt_dev_ptr;
		abi_ulong *target_rt_dev_ptr = NULL;
		unsigned long *host_rt_dev_ptr = NULL;
		abi_long ret;
		int i;

		@@ -4780,6 +4780,9 @@ static abi_long do_ioctl_rt(const IOCTLEntry ie, uint8_t buf_temp,
		unlock_user(argptr, arg, 0);

		ret = get_errno(safe_ioctl(fd, ie->host_cmd, buf_temp));

		assert(host_rt_dev_ptr != NULL);
		assert(target_rt_dev_ptr != NULL);
		if (*host_rt_dev_ptr != 0) {
		unlock_user((void )host_rt_dev_ptr,
		*target_rt_dev_ptr, 0);