Re: [PATCH net] net/smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint

[Leon Romanovsky <leon@kernel.org>]

On Sun, May 17, 2026 at 11:08:44PM +0800, Dust Li wrote:
> On 2026-05-17 11:45:13, Leon Romanovsky wrote:
> >On Sun, May 10, 2026 at 03:26:40PM -0700, Xiang Mei wrote:
> >> The smc_msg_event tracepoint class, shared by smc_tx_sendmsg and
> >> smc_rx_recvmsg, unconditionally dereferences smc->conn.lnk:
> >> 
> >> 	__string(name, smc->conn.lnk->ibname)
> >
> >My comment is not directly related to this patch, but it was triggered
> >while reviewing it. The ibname should not be cached, as users can rename
> >it through rdmatool or udev.
> >
> >For example, this function is racy:
> >   552 static int smc_nl_handle_smcr_dev(struct smc_ib_device *smcibdev,
> >   553                                   struct sk_buff *skb,
> >   554                                   struct netlink_callback *cb)
> >   555 {
> >   ...
> >   582         snprintf(smc_ibname, sizeof(smc_ibname), "%s", smcibdev->ibdev->name);
> >
> >Thanks
> 
> Hi, Leon
> 
> OK, I'll submit a patch removing all the ibvdev->name in SMC.

Thanks

> 
> Best regards,
> Dust
>