[Spice-devel] [PATCH 15/18] Avoid to call munmap with invalid size

[Christophe Fergeau]

On Mon, Sep 26, 2016 at 09:12:48AM +0100, Frediano Ziglio wrote:
> This could have happened if mremap failed.

If mremap fails, reds_stat  will be set to MAP_FAILED, so munmap will
not be called.

Christophe

> 
> Signed-off-by: Frediano Ziglio <fziglio at redhat.com>
> ---
>  tools/reds_stat.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/reds_stat.c b/tools/reds_stat.c
> index 945659e..d7d82ec 100644
> --- a/tools/reds_stat.c
> +++ b/tools/reds_stat.c
> @@ -66,7 +66,7 @@ int main(int argc, char **argv)
>      pid_t kvm_pid;
>      uint32_t num_of_nodes = 0;
>      size_t shm_size;
> -    size_t shm_old_size;
> +    size_t shm_new_size;
>      int shm_name_len;
>      int ret = -1;
>      int fd;
> @@ -105,13 +105,13 @@ int main(int argc, char **argv)
>          printf("spice statistics\n\n");
>          if (num_of_nodes != reds_stat->num_of_nodes) {
>              num_of_nodes = reds_stat->num_of_nodes;
> -            shm_old_size = shm_size;
> -            shm_size = sizeof(SpiceStat) + num_of_nodes * sizeof(SpiceStatNode);
> -            reds_stat = mremap(reds_stat, shm_old_size, shm_size, MREMAP_MAYMOVE);
> +            shm_new_size = sizeof(SpiceStat) + num_of_nodes * sizeof(SpiceStatNode);
> +            reds_stat = mremap(reds_stat, shm_size, shm_new_size, MREMAP_MAYMOVE);
>              if (reds_stat == (SpiceStat *)MAP_FAILED) {
>                  perror("mremap");
>                  goto error;
>              }
> +            shm_size = shm_new_size;
>              values = (uint64_t *)realloc(values, num_of_nodes * sizeof(uint64_t));
>              if (values == NULL) {
>                  perror("realloc");
> -- 
> 2.7.4
> 
> _______________________________________________
> Spice-devel mailing list
> Spice-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/spice-devel
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 801 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/spice-devel/attachments/20160927/3b32ac03/attachment.sig>