diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-10-21 22:44:48 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-10-21 22:44:48 -0400 |
commit | b5ac3beb5a9f0ef0ea64cd85faf94c0dc4de0e42 (patch) | |
tree | 70a8d684c18f71aa4be2d67896362f864afb4d57 /kernel/bpf/verifier.c | |
parent | e5f468b3f23313994c5e6c356135f9b0d76bcb94 (diff) | |
parent | 8d5f4b07174976c55a5f5d6967777373c6826944 (diff) | |
download | linux-b5ac3beb5a9f0ef0ea64cd85faf94c0dc4de0e42.tar.bz2 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
"A little more than usual this time around. Been travelling, so that is
part of it.
Anyways, here are the highlights:
1) Deal with memcontrol races wrt. listener dismantle, from Eric
Dumazet.
2) Handle page allocation failures properly in nfp driver, from Jaku
Kicinski.
3) Fix memory leaks in macsec, from Sabrina Dubroca.
4) Fix crashes in pppol2tp_session_ioctl(), from Guillaume Nault.
5) Several fixes in bnxt_en driver, including preventing potential
NVRAM parameter corruption from Michael Chan.
6) Fix for KRACK attacks in wireless, from Johannes Berg.
7) rtnetlink event generation fixes from Xin Long.
8) Deadlock in mlxsw driver, from Ido Schimmel.
9) Disallow arithmetic operations on context pointers in bpf, from
Jakub Kicinski.
10) Missing sock_owned_by_user() check in sctp_icmp_redirect(), from
Xin Long.
11) Only TCP is supported for sockmap, make that explicit with a
check, from John Fastabend.
12) Fix IP options state races in DCCP and TCP, from Eric Dumazet.
13) Fix panic in packet_getsockopt(), also from Eric Dumazet.
14) Add missing locked in hv_sock layer, from Dexuan Cui.
15) Various aquantia bug fixes, including several statistics handling
cures. From Igor Russkikh et al.
16) Fix arithmetic overflow in devmap code, from John Fastabend.
17) Fix busted socket memory accounting when we get a fault in the tcp
zero copy paths. From Willem de Bruijn.
18) Don't leave opt->tot_len uninitialized in ipv6, from Eric Dumazet"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (106 commits)
stmmac: Don't access tx_q->dirty_tx before netif_tx_lock
ipv6: flowlabel: do not leave opt->tot_len with garbage
of_mdio: Fix broken PHY IRQ in case of probe deferral
textsearch: fix typos in library helpers
rxrpc: Don't release call mutex on error pointer
net: stmmac: Prevent infinite loop in get_rx_timestamp_status()
net: stmmac: Fix stmmac_get_rx_hwtstamp()
net: stmmac: Add missing call to dev_kfree_skb()
mlxsw: spectrum_router: Configure TIGCR on init
mlxsw: reg: Add Tunneling IPinIP General Configuration Register
net: ethtool: remove error check for legacy setting transceiver type
soreuseport: fix initialization race
net: bridge: fix returning of vlan range op errors
sock: correct sk_wmem_queued accounting on efault in tcp zerocopy
bpf: add test cases to bpf selftests to cover all access tests
bpf: fix pattern matches for direct packet access
bpf: fix off by one for range markings with L{T, E} patterns
bpf: devmap fix arithmetic overflow in bitmap_size calculation
net: aquantia: Bad udp rate on default interrupt coalescing
net: aquantia: Enable coalescing management via ethtool interface
...
Diffstat (limited to 'kernel/bpf/verifier.c')
-rw-r--r-- | kernel/bpf/verifier.c | 65 |
1 files changed, 51 insertions, 14 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 8b8d6ba39e23..c48ca2a34b5e 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1116,7 +1116,12 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn /* ctx accesses must be at a fixed offset, so that we can * determine what type of data were returned. */ - if (!tnum_is_const(reg->var_off)) { + if (reg->off) { + verbose("dereference of modified ctx ptr R%d off=%d+%d, ctx+const is allowed, ctx+const+const is not\n", + regno, reg->off, off - reg->off); + return -EACCES; + } + if (!tnum_is_const(reg->var_off) || reg->var_off.value) { char tn_buf[48]; tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off); @@ -1124,7 +1129,6 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn tn_buf, off, size); return -EACCES; } - off += reg->var_off.value; err = check_ctx_access(env, insn_idx, off, size, t, ®_type); if (!err && t == BPF_READ && value_regno >= 0) { /* ctx access returns either a scalar, or a @@ -2426,12 +2430,15 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) } static void find_good_pkt_pointers(struct bpf_verifier_state *state, - struct bpf_reg_state *dst_reg) + struct bpf_reg_state *dst_reg, + bool range_right_open) { struct bpf_reg_state *regs = state->regs, *reg; + u16 new_range; int i; - if (dst_reg->off < 0) + if (dst_reg->off < 0 || + (dst_reg->off == 0 && range_right_open)) /* This doesn't give us any range */ return; @@ -2442,9 +2449,13 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state, */ return; - /* LLVM can generate four kind of checks: + new_range = dst_reg->off; + if (range_right_open) + new_range--; + + /* Examples for register markings: * - * Type 1/2: + * pkt_data in dst register: * * r2 = r3; * r2 += 8; @@ -2461,7 +2472,7 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state, * r2=pkt(id=n,off=8,r=0) * r3=pkt(id=n,off=0,r=0) * - * Type 3/4: + * pkt_data in src register: * * r2 = r3; * r2 += 8; @@ -2479,7 +2490,9 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state, * r3=pkt(id=n,off=0,r=0) * * Find register r3 and mark its range as r3=pkt(id=n,off=0,r=8) - * so that range of bytes [r3, r3 + 8) is safe to access. + * or r3=pkt(id=n,off=0,r=8-1), so that range of bytes [r3, r3 + 8) + * and [r3, r3 + 8-1) respectively is safe to access depending on + * the check. */ /* If our ids match, then we must have the same max_value. And we @@ -2490,14 +2503,14 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state, for (i = 0; i < MAX_BPF_REG; i++) if (regs[i].type == PTR_TO_PACKET && regs[i].id == dst_reg->id) /* keep the maximum range already checked */ - regs[i].range = max_t(u16, regs[i].range, dst_reg->off); + regs[i].range = max(regs[i].range, new_range); for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) { if (state->stack_slot_type[i] != STACK_SPILL) continue; reg = &state->spilled_regs[i / BPF_REG_SIZE]; if (reg->type == PTR_TO_PACKET && reg->id == dst_reg->id) - reg->range = max_t(u16, reg->range, dst_reg->off); + reg->range = max(reg->range, new_range); } } @@ -2861,19 +2874,43 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGT && dst_reg->type == PTR_TO_PACKET && regs[insn->src_reg].type == PTR_TO_PACKET_END) { - find_good_pkt_pointers(this_branch, dst_reg); + /* pkt_data' > pkt_end */ + find_good_pkt_pointers(this_branch, dst_reg, false); + } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGT && + dst_reg->type == PTR_TO_PACKET_END && + regs[insn->src_reg].type == PTR_TO_PACKET) { + /* pkt_end > pkt_data' */ + find_good_pkt_pointers(other_branch, ®s[insn->src_reg], true); } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLT && dst_reg->type == PTR_TO_PACKET && regs[insn->src_reg].type == PTR_TO_PACKET_END) { - find_good_pkt_pointers(other_branch, dst_reg); + /* pkt_data' < pkt_end */ + find_good_pkt_pointers(other_branch, dst_reg, true); + } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLT && + dst_reg->type == PTR_TO_PACKET_END && + regs[insn->src_reg].type == PTR_TO_PACKET) { + /* pkt_end < pkt_data' */ + find_good_pkt_pointers(this_branch, ®s[insn->src_reg], false); + } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGE && + dst_reg->type == PTR_TO_PACKET && + regs[insn->src_reg].type == PTR_TO_PACKET_END) { + /* pkt_data' >= pkt_end */ + find_good_pkt_pointers(this_branch, dst_reg, true); } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGE && dst_reg->type == PTR_TO_PACKET_END && regs[insn->src_reg].type == PTR_TO_PACKET) { - find_good_pkt_pointers(other_branch, ®s[insn->src_reg]); + /* pkt_end >= pkt_data' */ + find_good_pkt_pointers(other_branch, ®s[insn->src_reg], false); + } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLE && + dst_reg->type == PTR_TO_PACKET && + regs[insn->src_reg].type == PTR_TO_PACKET_END) { + /* pkt_data' <= pkt_end */ + find_good_pkt_pointers(other_branch, dst_reg, false); } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLE && dst_reg->type == PTR_TO_PACKET_END && regs[insn->src_reg].type == PTR_TO_PACKET) { - find_good_pkt_pointers(this_branch, ®s[insn->src_reg]); + /* pkt_end <= pkt_data' */ + find_good_pkt_pointers(this_branch, ®s[insn->src_reg], true); } else if (is_pointer_value(env, insn->dst_reg)) { verbose("R%d pointer comparison prohibited\n", insn->dst_reg); return -EACCES; |