From 2ed46ce45ec02f6b2188419acdf372a144e06fb5 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 11 Aug 2017 18:31:25 +0200 Subject: [PATCH] bpf: fix two missing target_size settings in bpf_convert_ctx_access When CONFIG_NET_SCHED or CONFIG_NET_RX_BUSY_POLL is /not/ set and we try a narrow __sk_buff load of tc_index or napi_id, respectively, then verifier rightfully complains that it's misconfigured, because we need to set target_size in each of the two cases. The rewrite for the ctx access is just a dummy op, but needs to pass, so fix this up. Fixes: f96da09473b5 ("bpf: simplify narrower ctx access") Reported-by: Shubham Bansal Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller --- net/core/filter.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/core/filter.c b/net/core/filter.c index f44fc22fd45a..6280a602604c 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3505,6 +3505,7 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type, bpf_target_off(struct sk_buff, tc_index, 2, target_size)); #else + *target_size = 2; if (type == BPF_WRITE) *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg); else @@ -3520,6 +3521,7 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type, *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1); *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); #else + *target_size = 4; *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); #endif break; -- 2.30.2