On 24 July 2017 at 19:27, Philippe Mathieu-Daudé <[email protected]> wrote:
> Clang's scan-build-5.0 reports:
>
> linux-user/syscall.c:5581:9: warning: Dereference of undefined pointer value
> if (*host_rt_dev_ptr != 0) {
> ^~~~~~~~~~~~~~~~
>
> Reported-by: Clang Static Analyzer
> Suggested-by: Laurent Vivier <[email protected]>
> Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
> ---
> linux-user/syscall.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index fcd20fa276..e79b5baec4 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -5524,7 +5524,7 @@ static abi_long do_ioctl_rt(const IOCTLEntry *ie,
> uint8_t *buf_temp,
> int target_size;
> void *argptr;
> abi_ulong *target_rt_dev_ptr;
> - unsigned long *host_rt_dev_ptr;
> + unsigned long *host_rt_dev_ptr = NULL;
> abi_long ret;
> int i;
>
> @@ -5570,6 +5570,7 @@ 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);
There's not much point in this assert because it doesn't
tell us anything we're not about to find out immediately
by dereferencing the pointer...
> if (*host_rt_dev_ptr != 0) {
> unlock_user((void *)*host_rt_dev_ptr,
> *target_rt_dev_ptr, 0);
> --
> 2.13.3
thanks
-- PMM
