4.9-stable review patch. If anyone has any objections, please let me know.
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From: Ben Hutchings ben.hutchings@codethink.co.uk
Extracted from commit 31fd85816dbe "bpf: permits narrower load from bpf program context fields".
Cc: Daniel Borkmann daniel@iogearbox.net Cc: Alexei Starovoitov ast@kernel.org Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/bpf/verifier.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)
--- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -745,7 +745,7 @@ static int check_ptr_alignment(struct bp * if t==write && value_regno==-1, some unknown value is stored into memory * if t==read && value_regno==-1, don't care what we read from memory */ -static int check_mem_access(struct bpf_verifier_env *env, u32 regno, int off, +static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regno, int off, int bpf_size, enum bpf_access_type t, int value_regno) { @@ -875,7 +875,7 @@ static int check_mem_access(struct bpf_v return err; }
-static int check_xadd(struct bpf_verifier_env *env, struct bpf_insn *insn) +static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn) { struct bpf_reg_state *regs = env->cur_state.regs; int err; @@ -908,13 +908,13 @@ static int check_xadd(struct bpf_verifie }
/* check whether atomic_add can read the memory */ - err = check_mem_access(env, insn->dst_reg, insn->off, + err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off, BPF_SIZE(insn->code), BPF_READ, -1); if (err) return err;
/* check whether atomic_add can write into the same memory */ - return check_mem_access(env, insn->dst_reg, insn->off, + return check_mem_access(env, insn_idx, insn->dst_reg, insn->off, BPF_SIZE(insn->code), BPF_WRITE, -1); }
@@ -1270,7 +1270,7 @@ static int check_call(struct bpf_verifie * is inferred from register state. */ for (i = 0; i < meta.access_size; i++) { - err = check_mem_access(env, meta.regno, i, BPF_B, BPF_WRITE, -1); + err = check_mem_access(env, insn_idx, meta.regno, i, BPF_B, BPF_WRITE, -1); if (err) return err; } @@ -2936,7 +2936,7 @@ static int do_check(struct bpf_verifier_ /* check that memory (src_reg + off) is readable, * the state of dst_reg will be updated by this func */ - err = check_mem_access(env, insn->src_reg, insn->off, + err = check_mem_access(env, insn_idx, insn->src_reg, insn->off, BPF_SIZE(insn->code), BPF_READ, insn->dst_reg); if (err) @@ -2976,7 +2976,7 @@ static int do_check(struct bpf_verifier_ enum bpf_reg_type *prev_dst_type, dst_reg_type;
if (BPF_MODE(insn->code) == BPF_XADD) { - err = check_xadd(env, insn); + err = check_xadd(env, insn_idx, insn); if (err) return err; insn_idx++; @@ -2995,7 +2995,7 @@ static int do_check(struct bpf_verifier_ dst_reg_type = regs[insn->dst_reg].type;
/* check that memory (dst_reg + off) is writeable */ - err = check_mem_access(env, insn->dst_reg, insn->off, + err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off, BPF_SIZE(insn->code), BPF_WRITE, insn->src_reg); if (err) @@ -3030,7 +3030,7 @@ static int do_check(struct bpf_verifier_ }
/* check that memory (dst_reg + off) is writeable */ - err = check_mem_access(env, insn->dst_reg, insn->off, + err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off, BPF_SIZE(insn->code), BPF_WRITE, -1); if (err)