On 2011-09-27 12:56, Fabien Chouteau wrote: > On 27/09/2011 11:20, Thomas Huth wrote: >> >> The two new variables "arp_requested" and "expiration_date" in the mbuf >> structure have been added after the variable-sized "m_dat_" array. The >> variables have to be added before the m_dat_ array instead. >> Without this patch, the expiration_date gets clobbered by code that >> accesses the m_dat_ array. >> I experienced this problem with the code in slirp/tftp.c: The >> tftp_send_data() function created a new packet with the m_get() >> function (which fills-in a default expiration_date value). Then the >> TFTP code cleared the data section of the packet, which accidentially >> also cleared the expiration_date. This zeroed expiration_date then >> finally causes the packet to be discarded during if_start(), so that >> TFTP packets were not transmitted anymore. >> > > Thanks for the patch Thomas. > > I think we can add a comment to avoid this kind of mistake in the > future. > > /* This is a "flexible array member". It should always remain > * the last member of the structure. > */
Good point, folded something like that in. Thanks, Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux
