On Thu, Jul 6, 2023 at 10:03 AM Christian Göttsche
<cgzones@xxxxxxxxxxxxxx> wrote:
>
> put_entry() is used during writing binary policies. Avoid short writes
> due to an overflow.
>
> Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
Acked-by: James Carter <jwcart2@xxxxxxxxx>
> ---
> libsepol/src/services.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/libsepol/src/services.c b/libsepol/src/services.c
> index 062510ab..07ae051b 100644
> --- a/libsepol/src/services.c
> +++ b/libsepol/src/services.c
> @@ -1708,7 +1708,10 @@ int next_entry(void *buf, struct policy_file *fp, size_t bytes)
> size_t put_entry(const void *ptr, size_t size, size_t n,
> struct policy_file *fp)
> {
> - size_t bytes = size * n;
> + size_t bytes;
> +
> + if (__builtin_mul_overflow(size, n, &bytes))
> + return 0;
>
> switch (fp->type) {
> case PF_USE_STDIO:
> --
> 2.40.1
>
