On Tue, Jun 25, 2019 at 01:29:35PM -0700, Josh Hunt wrote:
On 6/25/19 1:26 PM, Sasha Levin wrote:
On Tue, Jun 25, 2019 at 01:19:37PM -0400, Josh Hunt wrote:
Backport of dad3a9314ac95dedc007bc7dacacb396ea10e376:
You probably meant b6653b3629e5b88202be3c9abc44713973f5c4b4 here.
I wasn't sure if I should reference the upstream commit or stable commit.
The upstream commit please.
dad3a9314 is the version of the commit from linux-4.14.y. There may be a similar issue with the Fixes tag below since that also references the 4.14 vers of the change.
tcp_fragment() might be called for skbs in the write queue.
Memory limits might have been exceeded because tcp_sendmsg() only checks limits at full skb (64KB) boundaries.
Therefore, we need to make sure tcp_fragment() wont punish applications that might have setup very low SO_SNDBUF values.
Backport notes: Initial version used tcp_queue type which is not present in older kernels, so added a new arg to tcp_fragment() to determine whether this is a retransmit or not.
Fixes: 9daf226ff926 ("tcp: tcp_fragment() should apply sane memory limits") Signed-off-by: Josh Hunt johunt@akamai.com Reviewed-by: Jason Baron jbaron@akamai.com
Eric/Greg - This applies on top of v4.14.130. I did not see anything come through for the older (<4.19) stable kernels yet. Without this change Christoph Paasch's packetrill script (https://lore.kernel.org/netdev/CALMXkpYVRxgeqarp4gnmX7GqYh1sWOAt6UaRFqYBOaaN...)
will fail on 4.14 stable kernels, but passes with this change.
Eric, it would be great if you could Ack this, it's very different from your original patch.
Yes, that would be great.
I would prefer if this looks a bit more like the upstream fix, perhaps a backport of the function that added the "direction" of the packet first, and then Eric's patch? As it is, this patch adds a different parameter to the function than what is in Linus's tree, and I bet will cause problems at some later point in time.
thanks,
greg k-h