Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Alexei Starovoitov says:

====================
pull-request: bpf 2019-04-25

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) the bpf verifier fix to properly mark registers in all stack frames, from Paul.

2) preempt_enable_no_resched->preempt_enable fix, from Peter.

3) other misc fixes.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2019-04-26 01:54:42 -04:00
commit ad759c9069
7 changed files with 101 additions and 33 deletions

View File

@ -186,8 +186,9 @@ enum which_ebpf_reg {
* separate frame pointer, so BPF_REG_10 relative accesses are
* adjusted to be $sp relative.
*/
int ebpf_to_mips_reg(struct jit_ctx *ctx, const struct bpf_insn *insn,
enum which_ebpf_reg w)
static int ebpf_to_mips_reg(struct jit_ctx *ctx,
const struct bpf_insn *insn,
enum which_ebpf_reg w)
{
int ebpf_reg = (w == src_reg || w == src_reg_no_fp) ?
insn->src_reg : insn->dst_reg;

View File

@ -510,7 +510,7 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
} \
_out: \
rcu_read_unlock(); \
preempt_enable_no_resched(); \
preempt_enable(); \
_ret; \
})

View File

@ -4138,15 +4138,35 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
return 0;
}
static void __find_good_pkt_pointers(struct bpf_func_state *state,
struct bpf_reg_state *dst_reg,
enum bpf_reg_type type, u16 new_range)
{
struct bpf_reg_state *reg;
int i;
for (i = 0; i < MAX_BPF_REG; i++) {
reg = &state->regs[i];
if (reg->type == type && reg->id == dst_reg->id)
/* keep the maximum range already checked */
reg->range = max(reg->range, new_range);
}
bpf_for_each_spilled_reg(i, state, reg) {
if (!reg)
continue;
if (reg->type == type && reg->id == dst_reg->id)
reg->range = max(reg->range, new_range);
}
}
static void find_good_pkt_pointers(struct bpf_verifier_state *vstate,
struct bpf_reg_state *dst_reg,
enum bpf_reg_type type,
bool range_right_open)
{
struct bpf_func_state *state = vstate->frame[vstate->curframe];
struct bpf_reg_state *regs = state->regs, *reg;
u16 new_range;
int i, j;
int i;
if (dst_reg->off < 0 ||
(dst_reg->off == 0 && range_right_open))
@ -4211,20 +4231,9 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *vstate,
* the range won't allow anything.
* dst_reg->off is known < MAX_PACKET_OFF, therefore it fits in a u16.
*/
for (i = 0; i < MAX_BPF_REG; i++)
if (regs[i].type == type && regs[i].id == dst_reg->id)
/* keep the maximum range already checked */
regs[i].range = max(regs[i].range, new_range);
for (j = 0; j <= vstate->curframe; j++) {
state = vstate->frame[j];
bpf_for_each_spilled_reg(i, state, reg) {
if (!reg)
continue;
if (reg->type == type && reg->id == dst_reg->id)
reg->range = max(reg->range, new_range);
}
}
for (i = 0; i <= vstate->curframe; i++)
__find_good_pkt_pointers(vstate->frame[i], dst_reg, type,
new_range);
}
/* compute branch direction of the expression "if (reg opcode val) goto target;"
@ -4698,6 +4707,22 @@ static void mark_ptr_or_null_reg(struct bpf_func_state *state,
}
}
static void __mark_ptr_or_null_regs(struct bpf_func_state *state, u32 id,
bool is_null)
{
struct bpf_reg_state *reg;
int i;
for (i = 0; i < MAX_BPF_REG; i++)
mark_ptr_or_null_reg(state, &state->regs[i], id, is_null);
bpf_for_each_spilled_reg(i, state, reg) {
if (!reg)
continue;
mark_ptr_or_null_reg(state, reg, id, is_null);
}
}
/* The logic is similar to find_good_pkt_pointers(), both could eventually
* be folded together at some point.
*/
@ -4705,10 +4730,10 @@ static void mark_ptr_or_null_regs(struct bpf_verifier_state *vstate, u32 regno,
bool is_null)
{
struct bpf_func_state *state = vstate->frame[vstate->curframe];
struct bpf_reg_state *reg, *regs = state->regs;
struct bpf_reg_state *regs = state->regs;
u32 ref_obj_id = regs[regno].ref_obj_id;
u32 id = regs[regno].id;
int i, j;
int i;
if (ref_obj_id && ref_obj_id == id && is_null)
/* regs[regno] is in the " == NULL" branch.
@ -4717,17 +4742,8 @@ static void mark_ptr_or_null_regs(struct bpf_verifier_state *vstate, u32 regno,
*/
WARN_ON_ONCE(release_reference_state(state, id));
for (i = 0; i < MAX_BPF_REG; i++)
mark_ptr_or_null_reg(state, &regs[i], id, is_null);
for (j = 0; j <= vstate->curframe; j++) {
state = vstate->frame[j];
bpf_for_each_spilled_reg(i, state, reg) {
if (!reg)
continue;
mark_ptr_or_null_reg(state, reg, id, is_null);
}
}
for (i = 0; i <= vstate->curframe; i++)
__mark_ptr_or_null_regs(vstate->frame[i], id, is_null);
}
static bool try_match_pkt_pointers(const struct bpf_insn *insn,

View File

@ -1151,6 +1151,9 @@ static int do_create(int argc, char **argv)
return -1;
}
NEXT_ARG();
} else {
p_err("unknown arg %s", *argv);
return -1;
}
}

View File

@ -1,3 +1,4 @@
libbpf_version.h
FEATURE-DUMP.libbpf
test_libbpf
libbpf.so.*

View File

@ -374,6 +374,31 @@
.prog_type = BPF_PROG_TYPE_XDP,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"calls: ptr null check in subprog",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_6, 0),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
},
.errstr_unpriv = "function calls to other bpf functions are allowed for root only",
.fixup_map_hash_48b = { 3 },
.result_unpriv = REJECT,
.result = ACCEPT,
.retval = 0,
},
{
"calls: two calls with args",
.insns = {

View File

@ -631,3 +631,25 @@
.errstr = "invalid access to packet",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
"direct packet access: test29 (reg > pkt_end in subprog)",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, data)),
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
offsetof(struct __sk_buff, data_end)),
BPF_MOV64_REG(BPF_REG_3, BPF_REG_6),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 8),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_6, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_REG(BPF_JGT, BPF_REG_3, BPF_REG_2, 1),
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},