On 30/10/2019 07:52, David Marchand wrote: > On Tue, Oct 1, 2019 at 2:54 PM Kevin Traynor <[email protected]> wrote: >> >> Previously rx/tx_queues were passed into eth_from_pcaps_common() >> as ptrs and were checked for being NULL. >> >> In commit da6ba28f0540 ("net/pcap: use a struct to pass user options") >> that changed to pass in a ptr to a pmd_devargs_all which contains >> the rx/tx_queues. >> >> The parameter checking was not updated as part of that commit and >> coverity caught that there was still a check if rx/tx_queues were >> NULL, apparently after they had been dereferenced. >> >> Fix that by checking the pmd_devargs_all ptr and removing the NULL >> checks on rx/tx_queues. >> >> 1231 struct pmd_devargs *rx_queues = &devargs_all->rx_queues; >> 1232 struct pmd_devargs *tx_queues = &devargs_all->tx_queues; >> 1233 const unsigned int nb_rx_queues = rx_queues->num_of_queue; >> deref_ptr: Directly dereferencing pointer tx_queues. >> 1234 const unsigned int nb_tx_queues = tx_queues->num_of_queue; >> 1235 unsigned int i; >> 1236 >> 1237 /* do some parameter checking */ >> CID 345004: Dereference before null check (REVERSE_INULL) >> [select issue] >> 1238 if (rx_queues == NULL && nb_rx_queues > 0) >> 1239 return -1; >> CID 345029 (#1 of 1): Dereference before null check (REVERSE_INULL) >> check_after_deref: Null-checking tx_queues suggests that it may be >> null, but it has already been dereferenced on all paths leading to >> the check. >> 1240 if (tx_queues == NULL && nb_tx_queues > 0) >> 1241 return -1; >> >> Coverity issue: 345029 >> Coverity issue: 345044 >> Fixes: da6ba28f0540 ("net/pcap: use a struct to pass user options") >> Cc: [email protected] >> Cc: [email protected] >> >> Signed-off-by: Kevin Traynor <[email protected]> > > This patch hides the coverity warning. > But can't we just remove those checks? > > Iiuc, the checks on NULL pointers are unnecessary since > https://git.dpdk.org/dpdk/commit/?id=a0fce1193ce13a50c00624cb36605ebef7a3e60b. > >
Aside from the Coverity complaint about rxq/txq NULL check after use, the checks didn't seem to make sense anymore as rxq/txq are part of devargs_all struct now, so they were removed. I added the NULL check on devargs_all to avoid a NULL deference while getting them instead. The check isn't doing any harm, but looking at the current paths to this fn. can see devargs_all would not be NULL, so I'm ok to remove it too. Cian/Ferruh, wdyt?
