Re: [PATCH net] net/smc: avoid overwriting when adjusting sock bufsizes

From: Wen Gu
Date: Tue Jun 04 2024 - 07:13:33 EST




On 2024/5/31 16:54, Wen Gu wrote:
When copying smc settings to clcsock, avoid setting clcsock's sk_sndbuf
to sysctl_tcp_wmem[1], since this may overwrite the value set by
tcp_sndbuf_expand() in TCP connection establishment.

And the other setting sk_{snd|rcv}buf to sysctl value in
smc_adjust_sock_bufsizes() can also be omitted since the initialization
of smc sock and clcsock has set sk_{snd|rcv}buf to smc.sysctl_{w|r}mem
or ipv4_sysctl_tcp_{w|r}mem[1].

Fixes: 30c3c4a4497c ("net/smc: Use correct buffer sizes when switching between TCP and SMC")
Link: https://lore.kernel.org/r/5eaf3858-e7fd-4db8-83e8-3d7a3e0e9ae2@xxxxxxxxxxxxxxxxx
Signed-off-by: Wen Gu <guwen@xxxxxxxxxxxxxxxxx>
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FYI,
The detailed motivation and testing can be found in the link above.
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Hi, Gerd and Wenjia, do you think this makes sense? Thanks!