From 6088b5823b4cb132a838878747384cbfb5ce6646 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 9 Sep 2016 02:45:28 +0200 Subject: [PATCH 1/1] bpf: minor cleanups in helpers Some minor misc cleanups, f.e. use sizeof(__u32) instead of hardcoding and in __bpf_skb_max_len(), I missed that we always have skb->dev valid anyway, so we can drop the unneeded test for dev; also few more other misc bits addressed here. Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- kernel/bpf/helpers.c | 6 +++--- net/core/filter.c | 7 +++---- 2 files changed, 6 insertions(+), 7 deletions(-) diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 1ea3afba1a4f..6df73bd1ba34 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -126,7 +126,7 @@ static u64 bpf_get_current_pid_tgid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) { struct task_struct *task = current; - if (!task) + if (unlikely(!task)) return -EINVAL; return (u64) task->tgid << 32 | task->pid; @@ -144,12 +144,12 @@ static u64 bpf_get_current_uid_gid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) kuid_t uid; kgid_t gid; - if (!task) + if (unlikely(!task)) return -EINVAL; current_uid_gid(&uid, &gid); return (u64) from_kgid(&init_user_ns, gid) << 32 | - from_kuid(&init_user_ns, uid); + from_kuid(&init_user_ns, uid); } const struct bpf_func_proto bpf_get_current_uid_gid_proto = { diff --git a/net/core/filter.c b/net/core/filter.c index a83766be1ad2..628ed8c7d38d 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2010,8 +2010,7 @@ static u32 __bpf_skb_min_len(const struct sk_buff *skb) static u32 __bpf_skb_max_len(const struct sk_buff *skb) { - return skb->dev ? skb->dev->mtu + skb->dev->hard_header_len : - 65536; + return skb->dev->mtu + skb->dev->hard_header_len; } static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len) @@ -2605,7 +2604,7 @@ static bool __is_valid_xdp_access(int off, int size, return false; if (off % size != 0) return false; - if (size != 4) + if (size != sizeof(__u32)) return false; return true; @@ -2727,7 +2726,7 @@ static u32 bpf_net_convert_ctx_access(enum bpf_access_type type, int dst_reg, dst_reg, src_reg, insn); case offsetof(struct __sk_buff, cb[0]) ... - offsetof(struct __sk_buff, cb[4]): + offsetof(struct __sk_buff, cb[4]): BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20); prog->cb_access = 1; -- 2.20.1