diff options
Diffstat (limited to 'net/core/filter.c')
-rw-r--r-- | net/core/filter.c | 83 |
1 files changed, 41 insertions, 42 deletions
diff --git a/net/core/filter.c b/net/core/filter.c index ff943bed21af..2bc5376d4037 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -112,39 +112,41 @@ EXPORT_SYMBOL(sk_filter); */ unsigned int sk_run_filter(struct sk_buff *skb, struct sock_filter *filter, int flen) { - struct sock_filter *fentry; /* We walk down these */ void *ptr; u32 A = 0; /* Accumulator */ u32 X = 0; /* Index Register */ u32 mem[BPF_MEMWORDS]; /* Scratch Memory Store */ + unsigned long memvalid = 0; u32 tmp; int k; int pc; + BUILD_BUG_ON(BPF_MEMWORDS > BITS_PER_LONG); /* * Process array of filter instructions. */ for (pc = 0; pc < flen; pc++) { - fentry = &filter[pc]; + const struct sock_filter *fentry = &filter[pc]; + u32 f_k = fentry->k; switch (fentry->code) { case BPF_ALU|BPF_ADD|BPF_X: A += X; continue; case BPF_ALU|BPF_ADD|BPF_K: - A += fentry->k; + A += f_k; continue; case BPF_ALU|BPF_SUB|BPF_X: A -= X; continue; case BPF_ALU|BPF_SUB|BPF_K: - A -= fentry->k; + A -= f_k; continue; case BPF_ALU|BPF_MUL|BPF_X: A *= X; continue; case BPF_ALU|BPF_MUL|BPF_K: - A *= fentry->k; + A *= f_k; continue; case BPF_ALU|BPF_DIV|BPF_X: if (X == 0) @@ -152,49 +154,49 @@ unsigned int sk_run_filter(struct sk_buff *skb, struct sock_filter *filter, int A /= X; continue; case BPF_ALU|BPF_DIV|BPF_K: - A /= fentry->k; + A /= f_k; continue; case BPF_ALU|BPF_AND|BPF_X: A &= X; continue; case BPF_ALU|BPF_AND|BPF_K: - A &= fentry->k; + A &= f_k; continue; case BPF_ALU|BPF_OR|BPF_X: A |= X; continue; case BPF_ALU|BPF_OR|BPF_K: - A |= fentry->k; + A |= f_k; continue; case BPF_ALU|BPF_LSH|BPF_X: A <<= X; continue; case BPF_ALU|BPF_LSH|BPF_K: - A <<= fentry->k; + A <<= f_k; continue; case BPF_ALU|BPF_RSH|BPF_X: A >>= X; continue; case BPF_ALU|BPF_RSH|BPF_K: - A >>= fentry->k; + A >>= f_k; continue; case BPF_ALU|BPF_NEG: A = -A; continue; case BPF_JMP|BPF_JA: - pc += fentry->k; + pc += f_k; continue; case BPF_JMP|BPF_JGT|BPF_K: - pc += (A > fentry->k) ? fentry->jt : fentry->jf; + pc += (A > f_k) ? fentry->jt : fentry->jf; continue; case BPF_JMP|BPF_JGE|BPF_K: - pc += (A >= fentry->k) ? fentry->jt : fentry->jf; + pc += (A >= f_k) ? fentry->jt : fentry->jf; continue; case BPF_JMP|BPF_JEQ|BPF_K: - pc += (A == fentry->k) ? fentry->jt : fentry->jf; + pc += (A == f_k) ? fentry->jt : fentry->jf; continue; case BPF_JMP|BPF_JSET|BPF_K: - pc += (A & fentry->k) ? fentry->jt : fentry->jf; + pc += (A & f_k) ? fentry->jt : fentry->jf; continue; case BPF_JMP|BPF_JGT|BPF_X: pc += (A > X) ? fentry->jt : fentry->jf; @@ -209,7 +211,7 @@ unsigned int sk_run_filter(struct sk_buff *skb, struct sock_filter *filter, int pc += (A & X) ? fentry->jt : fentry->jf; continue; case BPF_LD|BPF_W|BPF_ABS: - k = fentry->k; + k = f_k; load_w: ptr = load_pointer(skb, k, 4, &tmp); if (ptr != NULL) { @@ -218,7 +220,7 @@ load_w: } break; case BPF_LD|BPF_H|BPF_ABS: - k = fentry->k; + k = f_k; load_h: ptr = load_pointer(skb, k, 2, &tmp); if (ptr != NULL) { @@ -227,7 +229,7 @@ load_h: } break; case BPF_LD|BPF_B|BPF_ABS: - k = fentry->k; + k = f_k; load_b: ptr = load_pointer(skb, k, 1, &tmp); if (ptr != NULL) { @@ -242,32 +244,34 @@ load_b: X = skb->len; continue; case BPF_LD|BPF_W|BPF_IND: - k = X + fentry->k; + k = X + f_k; goto load_w; case BPF_LD|BPF_H|BPF_IND: - k = X + fentry->k; + k = X + f_k; goto load_h; case BPF_LD|BPF_B|BPF_IND: - k = X + fentry->k; + k = X + f_k; goto load_b; case BPF_LDX|BPF_B|BPF_MSH: - ptr = load_pointer(skb, fentry->k, 1, &tmp); + ptr = load_pointer(skb, f_k, 1, &tmp); if (ptr != NULL) { X = (*(u8 *)ptr & 0xf) << 2; continue; } return 0; case BPF_LD|BPF_IMM: - A = fentry->k; + A = f_k; continue; case BPF_LDX|BPF_IMM: - X = fentry->k; + X = f_k; continue; case BPF_LD|BPF_MEM: - A = mem[fentry->k]; + A = (memvalid & (1UL << f_k)) ? + mem[f_k] : 0; continue; case BPF_LDX|BPF_MEM: - X = mem[fentry->k]; + X = (memvalid & (1UL << f_k)) ? + mem[f_k] : 0; continue; case BPF_MISC|BPF_TAX: X = A; @@ -276,14 +280,16 @@ load_b: A = X; continue; case BPF_RET|BPF_K: - return fentry->k; + return f_k; case BPF_RET|BPF_A: return A; case BPF_ST: - mem[fentry->k] = A; + memvalid |= 1UL << f_k; + mem[f_k] = A; continue; case BPF_STX: - mem[fentry->k] = X; + memvalid |= 1UL << f_k; + mem[f_k] = X; continue; default: WARN_ON(1); @@ -466,23 +472,16 @@ int sk_chk_filter(struct sock_filter *filter, int flen) EXPORT_SYMBOL(sk_chk_filter); /** - * sk_filter_rcu_release: Release a socket filter by rcu_head + * sk_filter_release_rcu: Release a socket filter by rcu_head * @rcu: rcu_head that contains the sk_filter to free */ -static void sk_filter_rcu_release(struct rcu_head *rcu) +void sk_filter_release_rcu(struct rcu_head *rcu) { struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu); - sk_filter_release(fp); -} - -static void sk_filter_delayed_uncharge(struct sock *sk, struct sk_filter *fp) -{ - unsigned int size = sk_filter_len(fp); - - atomic_sub(size, &sk->sk_omem_alloc); - call_rcu_bh(&fp->rcu, sk_filter_rcu_release); + kfree(fp); } +EXPORT_SYMBOL(sk_filter_release_rcu); /** * sk_attach_filter - attach a socket filter @@ -527,7 +526,7 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk) rcu_read_unlock_bh(); if (old_fp) - sk_filter_delayed_uncharge(sk, old_fp); + sk_filter_uncharge(sk, old_fp); return 0; } EXPORT_SYMBOL_GPL(sk_attach_filter); @@ -541,7 +540,7 @@ int sk_detach_filter(struct sock *sk) filter = rcu_dereference_bh(sk->sk_filter); if (filter) { rcu_assign_pointer(sk->sk_filter, NULL); - sk_filter_delayed_uncharge(sk, filter); + sk_filter_uncharge(sk, filter); ret = 0; } rcu_read_unlock_bh(); |