tcp/dccp: add SLAB_DESTROY_BY_RCU flag for request sockets
Before letting request sockets being put in TCP/DCCP regular
ehash table, we need to add either :
- SLAB_DESTROY_BY_RCU flag to their kmem_cache
- add RCU grace period before freeing them.
Since we carefully respected the SLAB_DESTROY_BY_RCU protocol
like ESTABLISH and TIMEWAIT sockets, use it here.
req_prot_init() being only used by TCP and DCCP, I did not add
a new slab_flags into their rsk_prot, but reuse prot->slab_flags
Since all reqsk_alloc() users are correctly dealing with a failure,
add the __GFP_NOWARN flag to avoid traces under pressure.
Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/sock.c b/net/core/sock.c
index 3307c02..7dd1263 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2758,7 +2758,7 @@
rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
rsk_prot->obj_size, 0,
- 0, NULL);
+ prot->slab_flags, NULL);
if (!rsk_prot->slab) {
pr_crit("%s: Can't create request sock SLAB cache!\n",
