Hi Dan,
Thanks for pointing this out.
The u_ctx pointer in case of ch_ktls will always be valid.
So this condition if(u_ctx && u_ctx->detach) must be if(u_ctx->detach).
and xa_erase(&u_ctx->tid_list, tx_info->tid) doesnot requires a u_ctx check.
So I will send a fix which replaces if(u_ctx && u_ctx->detach) to
if(u_ctx->detach)
and removes the checks for u_ctx pointer in ch_ktls driver.
Thanks,
Ayush
On 5/15/2021 4:12 PM, Dan Carpenter wrote:
Hello Ayush Sawal,
This is a semi-automatic email about new static checker warnings.
The patch 65e302a9bd57: "cxgb4/ch_ktls: Clear resources when pf4
device is removed" from May 13, 2021, leads to the following Smatch
complaint:
drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:393 chcr_ktls_dev_del()
error: we previously assumed 'u_ctx' could be null (see line 374)
drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c
373 u_ctx = tx_info->adap->uld[CXGB4_ULD_KTLS].handle;
374 if (u_ctx && u_ctx->detach)
^^^^^
Can u_ctx be NULL?
375 return;
376 /* clear l2t entry */
377 if (tx_info->l2te)
378 cxgb4_l2t_release(tx_info->l2te);
379
380 #if IS_ENABLED(CONFIG_IPV6)
381 /* clear clip entry */
382 if (tx_info->ip_family == AF_INET6)
383 cxgb4_clip_release(netdev, (const u32 *)
384 &tx_info->sk->sk_v6_rcv_saddr,
385 1);
386 #endif
387
388 /* clear tid */
389 if (tx_info->tid != -1) {
390 cxgb4_remove_tid(&tx_info->adap->tids, tx_info->tx_chan,
391 tx_info->tid, tx_info->ip_family);
392
393 xa_erase(&u_ctx->tid_list, tx_info->tid);
^^^^^^^^^^^^^^^^
Unchecked dereference.
394 }
395
regards,
dan carpenter
