On 2023-02-07 01:35 +01, Alexander Bluhm <alexander.bl...@gmx.net> wrote: > On Tue, Jan 31, 2023 at 11:32:44PM +0100, Jan Klemkow wrote: >> On Tue, Jan 31, 2023 at 09:12:51PM +0100, Christian Weisgerber wrote: >> > > - Check if the mbuf is large enough for an ether header. > >> if (m == NULL || m->m_len - hoff < sizeof(*ext->ip4)) > > Could you change this code to > > if (m == NULL || m->m_len < sizeof(*ext->ip4) + hoff) > > I don't want to think about what happens if there is an integer > underflow. Overflow cannot happen as hoff should be much smaller > than maximum size_t. Or is it just me who does not understand the > C conversion from negative int to size_t comparison. >
It's not just you...
