Re: [PATCH] softmmu/physmem.c: Check return value from realpath()

[Paolo Bonzini <pbonzini@redhat.com>]

On 12/08/21 17:15, Peter Maydell wrote:
> The realpath() function can return NULL on error, so we need to check
> for it to avoid crashing when we try to strstr() into it.
> This can happen if we run out of memory, or if /sys/ is not mounted,
> among other situations.
> 
> Fixes: Coverity 1459913, 1460474
> Fixes: ce317be98db0 ("exec: fetch the alignment of Linux devdax pmem character device nodes")
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>   softmmu/physmem.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/softmmu/physmem.c b/softmmu/physmem.c
> index c47cb6da2e4..eb0595d57c4 100644
> --- a/softmmu/physmem.c
> +++ b/softmmu/physmem.c
> @@ -1451,6 +1451,9 @@ static int64_t get_file_align(int fd)
>           path = g_strdup_printf("/sys/dev/char/%d:%d",
>                       major(st.st_rdev), minor(st.st_rdev));
>           rpath = realpath(path, NULL);
> +        if (!rpath) {
> +            return -errno;
> +        }
>   
>           rc = daxctl_new(&ctx);
>           if (rc) {
> 

Queued, thanks.

Paolo