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authorJohannes Berg <johannes.berg@intel.com>2016-10-04 09:22:19 +0200
committerJohannes Berg <johannes.berg@intel.com>2016-10-04 09:46:44 +0200
commit1e1430d5282bc3a572465ef3261eea793d98a653 (patch)
tree81c8883606ed2dd821f4509581888505d48631dd /include/linux/bpf_verifier.h
parentbb42f2d13ffcd0baed7547b37d05add51fcd50e1 (diff)
parent9a8dd213d2a38349e5ea2ca8888400952112b45c (diff)
Merge remote-tracking branch 'net-next/master' into mac80211-next
Resolve the merge conflict between Felix's/my and Toke's patches coming into the tree through net and mac80211-next respectively. Most of Felix's changes go away due to Toke's new infrastructure work, my patch changes to "goto begin" (the label wasn't there before) instead of returning NULL so flow control towards drivers is preserved better. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'include/linux/bpf_verifier.h')
-rw-r--r--include/linux/bpf_verifier.h102
1 files changed, 102 insertions, 0 deletions
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
new file mode 100644
index 000000000000..7035b997aaa5
--- /dev/null
+++ b/include/linux/bpf_verifier.h
@@ -0,0 +1,102 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#ifndef _LINUX_BPF_VERIFIER_H
+#define _LINUX_BPF_VERIFIER_H 1
+
+#include <linux/bpf.h> /* for enum bpf_reg_type */
+#include <linux/filter.h> /* for MAX_BPF_STACK */
+
+ /* Just some arbitrary values so we can safely do math without overflowing and
+ * are obviously wrong for any sort of memory access.
+ */
+#define BPF_REGISTER_MAX_RANGE (1024 * 1024 * 1024)
+#define BPF_REGISTER_MIN_RANGE -(1024 * 1024 * 1024)
+
+struct bpf_reg_state {
+ enum bpf_reg_type type;
+ /*
+ * Used to determine if any memory access using this register will
+ * result in a bad access.
+ */
+ u64 min_value, max_value;
+ union {
+ /* valid when type == CONST_IMM | PTR_TO_STACK | UNKNOWN_VALUE */
+ s64 imm;
+
+ /* valid when type == PTR_TO_PACKET* */
+ struct {
+ u32 id;
+ u16 off;
+ u16 range;
+ };
+
+ /* valid when type == CONST_PTR_TO_MAP | PTR_TO_MAP_VALUE |
+ * PTR_TO_MAP_VALUE_OR_NULL
+ */
+ struct bpf_map *map_ptr;
+ };
+};
+
+enum bpf_stack_slot_type {
+ STACK_INVALID, /* nothing was stored in this stack slot */
+ STACK_SPILL, /* register spilled into stack */
+ STACK_MISC /* BPF program wrote some data into this slot */
+};
+
+#define BPF_REG_SIZE 8 /* size of eBPF register in bytes */
+
+/* state of the program:
+ * type of all registers and stack info
+ */
+struct bpf_verifier_state {
+ struct bpf_reg_state regs[MAX_BPF_REG];
+ u8 stack_slot_type[MAX_BPF_STACK];
+ struct bpf_reg_state spilled_regs[MAX_BPF_STACK / BPF_REG_SIZE];
+};
+
+/* linked list of verifier states used to prune search */
+struct bpf_verifier_state_list {
+ struct bpf_verifier_state state;
+ struct bpf_verifier_state_list *next;
+};
+
+struct bpf_insn_aux_data {
+ enum bpf_reg_type ptr_type; /* pointer type for load/store insns */
+};
+
+#define MAX_USED_MAPS 64 /* max number of maps accessed by one eBPF program */
+
+struct bpf_verifier_env;
+struct bpf_ext_analyzer_ops {
+ int (*insn_hook)(struct bpf_verifier_env *env,
+ int insn_idx, int prev_insn_idx);
+};
+
+/* single container for all structs
+ * one verifier_env per bpf_check() call
+ */
+struct bpf_verifier_env {
+ struct bpf_prog *prog; /* eBPF program being verified */
+ struct bpf_verifier_stack_elem *head; /* stack of verifier states to be processed */
+ int stack_size; /* number of states to be processed */
+ struct bpf_verifier_state cur_state; /* current verifier state */
+ struct bpf_verifier_state_list **explored_states; /* search pruning optimization */
+ const struct bpf_ext_analyzer_ops *analyzer_ops; /* external analyzer ops */
+ void *analyzer_priv; /* pointer to external analyzer's private data */
+ struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */
+ u32 used_map_cnt; /* number of used maps */
+ u32 id_gen; /* used to generate unique reg IDs */
+ bool allow_ptr_leaks;
+ bool seen_direct_write;
+ bool varlen_map_value_access;
+ struct bpf_insn_aux_data *insn_aux_data; /* array of per-insn state */
+};
+
+int bpf_analyzer(struct bpf_prog *prog, const struct bpf_ext_analyzer_ops *ops,
+ void *priv);
+
+#endif /* _LINUX_BPF_VERIFIER_H */