diff options
| author | Tejun Heo <tj@kernel.org> | 2015-12-07 17:38:51 -0500 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-12-08 22:02:33 -0500 |
| commit | 297dbde19cf6a0ccb6fd4396c6220a5912ed61e8 (patch) | |
| tree | d1b65de60b8d8adfd2f84542cd59d9ed61f12c6b | |
| parent | bc9b145a092aca91a7f6ef40cdb3628b6ada7ec9 (diff) | |
| download | linux-297dbde19cf6a0ccb6fd4396c6220a5912ed61e8.tar.bz2 | |
netprio_cgroup: limit the maximum css->id to USHRT_MAX
netprio builds per-netdev contiguous priomap array which is indexed by
css->id. The array is allocated using kzalloc() effectively limiting
the maximum ID supported to some thousand range. This patch caps the
maximum supported css->id to USHRT_MAX which should be way above what
is actually useable.
This allows reducing sock->sk_cgrp_prioidx to u16 from u32. The freed
up part will be used to overload the cgroup related fields.
sock->sk_cgrp_prioidx's position is swapped with sk_mark so that the
two cgroup related fields are adjacent.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
CC: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/sock.h | 10 | ||||
| -rw-r--r-- | net/core/netprio_cgroup.c | 9 |
2 files changed, 14 insertions, 5 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 6f58b84fc742..a95bcf7d6efa 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -288,7 +288,6 @@ struct cg_proto; * @sk_ack_backlog: current listen backlog * @sk_max_ack_backlog: listen backlog set in listen() * @sk_priority: %SO_PRIORITY setting - * @sk_cgrp_prioidx: socket group's priority map index * @sk_type: socket type (%SOCK_STREAM, etc) * @sk_protocol: which protocol this socket belongs in this network family * @sk_peer_pid: &struct pid for this socket's peer @@ -309,6 +308,7 @@ struct cg_proto; * @sk_send_head: front of stuff to transmit * @sk_security: used by security modules * @sk_mark: generic packet mark + * @sk_cgrp_prioidx: socket group's priority map index * @sk_classid: this socket's cgroup classid * @sk_cgrp: this socket's cgroup-specific proto data * @sk_write_pending: a write to stream socket waits to start @@ -425,9 +425,7 @@ struct sock { u32 sk_ack_backlog; u32 sk_max_ack_backlog; __u32 sk_priority; -#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) - __u32 sk_cgrp_prioidx; -#endif + __u32 sk_mark; struct pid *sk_peer_pid; const struct cred *sk_peer_cred; long sk_rcvtimeo; @@ -445,7 +443,9 @@ struct sock { #ifdef CONFIG_SECURITY void *sk_security; #endif - __u32 sk_mark; +#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) + u16 sk_cgrp_prioidx; +#endif #ifdef CONFIG_CGROUP_NET_CLASSID u32 sk_classid; #endif diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c index cbd0a199bf52..2b9159b7a28a 100644 --- a/net/core/netprio_cgroup.c +++ b/net/core/netprio_cgroup.c @@ -27,6 +27,12 @@ #include <linux/fdtable.h> +/* + * netprio allocates per-net_device priomap array which is indexed by + * css->id. Limiting css ID to 16bits doesn't lose anything. + */ +#define NETPRIO_ID_MAX USHRT_MAX + #define PRIOMAP_MIN_SZ 128 /* @@ -144,6 +150,9 @@ static int cgrp_css_online(struct cgroup_subsys_state *css) struct net_device *dev; int ret = 0; + if (css->id > NETPRIO_ID_MAX) + return -ENOSPC; + if (!parent_css) return 0; |