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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-20 16:33:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-20 16:33:39 -0700
commit96080f697786e0a30006fcbcc5b53f350fcb3e9f (patch)
tree77b130e0e7714a55ce2a579f9524173e151e3b2d /kernel/bpf
parent63a86362130f4c17eaa57f3ef5171ec43111a54e (diff)
parentcbf5ecb305601d063dc94a57680dfbc3f96c188d (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller: 1) BPF verifier signed/unsigned value tracking fix, from Daniel Borkmann, Edward Cree, and Josef Bacik. 2) Fix memory allocation length when setting up calls to ->ndo_set_mac_address, from Cong Wang. 3) Add a new cxgb4 device ID, from Ganesh Goudar. 4) Fix FIB refcount handling, we have to set it's initial value before the configure callback (which can bump it). From David Ahern. 5) Fix double-free in qcom/emac driver, from Timur Tabi. 6) A bunch of gcc-7 string format overflow warning fixes from Arnd Bergmann. 7) Fix link level headroom tests in ip_do_fragment(), from Vasily Averin. 8) Fix chunk walking in SCTP when iterating over error and parameter headers. From Alexander Potapenko. 9) TCP BBR congestion control fixes from Neal Cardwell. 10) Fix SKB fragment handling in bcmgenet driver, from Doug Berger. 11) BPF_CGROUP_RUN_PROG_SOCK_OPS needs to check for null __sk, from Cong Wang. 12) xmit_recursion in ppp driver needs to be per-device not per-cpu, from Gao Feng. 13) Cannot release skb->dst in UDP if IP options processing needs it. From Paolo Abeni. 14) Some netdev ioctl ifr_name[] NULL termination fixes. From Alexander Levin and myself. 15) Revert some rtnetlink notification changes that are causing regressions, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (83 commits) net: bonding: Fix transmit load balancing in balance-alb mode rds: Make sure updates to cp_send_gen can be observed net: ethernet: ti: cpsw: Push the request_irq function to the end of probe ipv4: initialize fib_trie prior to register_netdev_notifier call. rtnetlink: allocate more memory for dev_set_mac_address() net: dsa: b53: Add missing ARL entries for BCM53125 bpf: more tests for mixed signed and unsigned bounds checks bpf: add test for mixed signed and unsigned bounds checks bpf: fix up test cases with mixed signed/unsigned bounds bpf: allow to specify log level and reduce it for test_verifier bpf: fix mixed signed/unsigned derived min/max value bounds ipv6: avoid overflow of offset in ip6_find_1stfragopt net: tehuti: don't process data if it has not been copied from userspace Revert "rtnetlink: Do not generate notifications for CHANGEADDR event" net: dsa: mv88e6xxx: Enable CMODE config support for 6390X dt-binding: ptp: Add SoC compatibility strings for dte ptp clock NET: dwmac: Make dwmac reset unconditional net: Zero terminate ifr_name in dev_ifname(). wireless: wext: terminate ifr name coming from userspace netfilter: fix netfilter_net_init() return ...
Diffstat (limited to 'kernel/bpf')
-rw-r--r--kernel/bpf/verifier.c108
1 files changed, 94 insertions, 14 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 6a86723c5b64..af9e84a4944e 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -504,6 +504,7 @@ static void reset_reg_range_values(struct bpf_reg_state *regs, u32 regno)
{
regs[regno].min_value = BPF_REGISTER_MIN_RANGE;
regs[regno].max_value = BPF_REGISTER_MAX_RANGE;
+ regs[regno].value_from_signed = false;
regs[regno].min_align = 0;
}
@@ -777,12 +778,13 @@ static int check_ctx_access(struct bpf_verifier_env *env, int insn_idx, int off,
return -EACCES;
}
-static bool is_pointer_value(struct bpf_verifier_env *env, int regno)
+static bool __is_pointer_value(bool allow_ptr_leaks,
+ const struct bpf_reg_state *reg)
{
- if (env->allow_ptr_leaks)
+ if (allow_ptr_leaks)
return false;
- switch (env->cur_state.regs[regno].type) {
+ switch (reg->type) {
case UNKNOWN_VALUE:
case CONST_IMM:
return false;
@@ -791,6 +793,11 @@ static bool is_pointer_value(struct bpf_verifier_env *env, int regno)
}
}
+static bool is_pointer_value(struct bpf_verifier_env *env, int regno)
+{
+ return __is_pointer_value(env->allow_ptr_leaks, &env->cur_state.regs[regno]);
+}
+
static int check_pkt_ptr_alignment(const struct bpf_reg_state *reg,
int off, int size, bool strict)
{
@@ -1832,10 +1839,24 @@ static void adjust_reg_min_max_vals(struct bpf_verifier_env *env,
dst_align = dst_reg->min_align;
/* We don't know anything about what was done to this register, mark it
- * as unknown.
+ * as unknown. Also, if both derived bounds came from signed/unsigned
+ * mixed compares and one side is unbounded, we cannot really do anything
+ * with them as boundaries cannot be trusted. Thus, arithmetic of two
+ * regs of such kind will get invalidated bounds on the dst side.
*/
- if (min_val == BPF_REGISTER_MIN_RANGE &&
- max_val == BPF_REGISTER_MAX_RANGE) {
+ if ((min_val == BPF_REGISTER_MIN_RANGE &&
+ max_val == BPF_REGISTER_MAX_RANGE) ||
+ (BPF_SRC(insn->code) == BPF_X &&
+ ((min_val != BPF_REGISTER_MIN_RANGE &&
+ max_val == BPF_REGISTER_MAX_RANGE) ||
+ (min_val == BPF_REGISTER_MIN_RANGE &&
+ max_val != BPF_REGISTER_MAX_RANGE) ||
+ (dst_reg->min_value != BPF_REGISTER_MIN_RANGE &&
+ dst_reg->max_value == BPF_REGISTER_MAX_RANGE) ||
+ (dst_reg->min_value == BPF_REGISTER_MIN_RANGE &&
+ dst_reg->max_value != BPF_REGISTER_MAX_RANGE)) &&
+ regs[insn->dst_reg].value_from_signed !=
+ regs[insn->src_reg].value_from_signed)) {
reset_reg_range_values(regs, insn->dst_reg);
return;
}
@@ -2023,6 +2044,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
regs[insn->dst_reg].max_value = insn->imm;
regs[insn->dst_reg].min_value = insn->imm;
regs[insn->dst_reg].min_align = calc_align(insn->imm);
+ regs[insn->dst_reg].value_from_signed = false;
}
} else if (opcode > BPF_END) {
@@ -2198,40 +2220,63 @@ static void reg_set_min_max(struct bpf_reg_state *true_reg,
struct bpf_reg_state *false_reg, u64 val,
u8 opcode)
{
+ bool value_from_signed = true;
+ bool is_range = true;
+
switch (opcode) {
case BPF_JEQ:
/* If this is false then we know nothing Jon Snow, but if it is
* true then we know for sure.
*/
true_reg->max_value = true_reg->min_value = val;
+ is_range = false;
break;
case BPF_JNE:
/* If this is true we know nothing Jon Snow, but if it is false
* we know the value for sure;
*/
false_reg->max_value = false_reg->min_value = val;
+ is_range = false;
break;
case BPF_JGT:
- /* Unsigned comparison, the minimum value is 0. */
- false_reg->min_value = 0;
+ value_from_signed = false;
/* fallthrough */
case BPF_JSGT:
+ if (true_reg->value_from_signed != value_from_signed)
+ reset_reg_range_values(true_reg, 0);
+ if (false_reg->value_from_signed != value_from_signed)
+ reset_reg_range_values(false_reg, 0);
+ if (opcode == BPF_JGT) {
+ /* Unsigned comparison, the minimum value is 0. */
+ false_reg->min_value = 0;
+ }
/* If this is false then we know the maximum val is val,
* otherwise we know the min val is val+1.
*/
false_reg->max_value = val;
+ false_reg->value_from_signed = value_from_signed;
true_reg->min_value = val + 1;
+ true_reg->value_from_signed = value_from_signed;
break;
case BPF_JGE:
- /* Unsigned comparison, the minimum value is 0. */
- false_reg->min_value = 0;
+ value_from_signed = false;
/* fallthrough */
case BPF_JSGE:
+ if (true_reg->value_from_signed != value_from_signed)
+ reset_reg_range_values(true_reg, 0);
+ if (false_reg->value_from_signed != value_from_signed)
+ reset_reg_range_values(false_reg, 0);
+ if (opcode == BPF_JGE) {
+ /* Unsigned comparison, the minimum value is 0. */
+ false_reg->min_value = 0;
+ }
/* If this is false then we know the maximum value is val - 1,
* otherwise we know the mimimum value is val.
*/
false_reg->max_value = val - 1;
+ false_reg->value_from_signed = value_from_signed;
true_reg->min_value = val;
+ true_reg->value_from_signed = value_from_signed;
break;
default:
break;
@@ -2239,6 +2284,12 @@ static void reg_set_min_max(struct bpf_reg_state *true_reg,
check_reg_overflow(false_reg);
check_reg_overflow(true_reg);
+ if (is_range) {
+ if (__is_pointer_value(false, false_reg))
+ reset_reg_range_values(false_reg, 0);
+ if (__is_pointer_value(false, true_reg))
+ reset_reg_range_values(true_reg, 0);
+ }
}
/* Same as above, but for the case that dst_reg is a CONST_IMM reg and src_reg
@@ -2248,41 +2299,64 @@ static void reg_set_min_max_inv(struct bpf_reg_state *true_reg,
struct bpf_reg_state *false_reg, u64 val,
u8 opcode)
{
+ bool value_from_signed = true;
+ bool is_range = true;
+
switch (opcode) {
case BPF_JEQ:
/* If this is false then we know nothing Jon Snow, but if it is
* true then we know for sure.
*/
true_reg->max_value = true_reg->min_value = val;
+ is_range = false;
break;
case BPF_JNE:
/* If this is true we know nothing Jon Snow, but if it is false
* we know the value for sure;
*/
false_reg->max_value = false_reg->min_value = val;
+ is_range = false;
break;
case BPF_JGT:
- /* Unsigned comparison, the minimum value is 0. */
- true_reg->min_value = 0;
+ value_from_signed = false;
/* fallthrough */
case BPF_JSGT:
+ if (true_reg->value_from_signed != value_from_signed)
+ reset_reg_range_values(true_reg, 0);
+ if (false_reg->value_from_signed != value_from_signed)
+ reset_reg_range_values(false_reg, 0);
+ if (opcode == BPF_JGT) {
+ /* Unsigned comparison, the minimum value is 0. */
+ true_reg->min_value = 0;
+ }
/*
* If this is false, then the val is <= the register, if it is
* true the register <= to the val.
*/
false_reg->min_value = val;
+ false_reg->value_from_signed = value_from_signed;
true_reg->max_value = val - 1;
+ true_reg->value_from_signed = value_from_signed;
break;
case BPF_JGE:
- /* Unsigned comparison, the minimum value is 0. */
- true_reg->min_value = 0;
+ value_from_signed = false;
/* fallthrough */
case BPF_JSGE:
+ if (true_reg->value_from_signed != value_from_signed)
+ reset_reg_range_values(true_reg, 0);
+ if (false_reg->value_from_signed != value_from_signed)
+ reset_reg_range_values(false_reg, 0);
+ if (opcode == BPF_JGE) {
+ /* Unsigned comparison, the minimum value is 0. */
+ true_reg->min_value = 0;
+ }
/* If this is false then constant < register, if it is true then
* the register < constant.
*/
false_reg->min_value = val + 1;
+ false_reg->value_from_signed = value_from_signed;
true_reg->max_value = val;
+ true_reg->value_from_signed = value_from_signed;
break;
default:
break;
@@ -2290,6 +2364,12 @@ static void reg_set_min_max_inv(struct bpf_reg_state *true_reg,
check_reg_overflow(false_reg);
check_reg_overflow(true_reg);
+ if (is_range) {
+ if (__is_pointer_value(false, false_reg))
+ reset_reg_range_values(false_reg, 0);
+ if (__is_pointer_value(false, true_reg))
+ reset_reg_range_values(true_reg, 0);
+ }
}
static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id,