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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-01-03 12:53:47 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-01-03 12:53:47 -0800 |
commit | 43d86ee8c639df750529b4d8f062b328b61c423e (patch) | |
tree | 076161dd7ce3f843b9c965a780ecfbf020f75e8e /kernel/bpf/core.c | |
parent | 645ff1e8e704c4f33ab1fcd3c87f95cb9b6d7144 (diff) | |
parent | c5ee066333ebc322a24a00a743ed941a0c68617e (diff) | |
download | linux-43d86ee8c639df750529b4d8f062b328b61c423e.tar.gz linux-43d86ee8c639df750529b4d8f062b328b61c423e.tar.bz2 linux-43d86ee8c639df750529b4d8f062b328b61c423e.zip |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
"Several fixes here. Basically split down the line between newly
introduced regressions and long existing problems:
1) Double free in tipc_enable_bearer(), from Cong Wang.
2) Many fixes to nf_conncount, from Florian Westphal.
3) op->get_regs_len() can throw an error, check it, from Yunsheng
Lin.
4) Need to use GFP_ATOMIC in *_add_hash_mac_address() of fsl/fman
driver, from Scott Wood.
5) Inifnite loop in fib_empty_table(), from Yue Haibing.
6) Use after free in ax25_fillin_cb(), from Cong Wang.
7) Fix socket locking in nr_find_socket(), also from Cong Wang.
8) Fix WoL wakeup enable in r8169, from Heiner Kallweit.
9) On 32-bit sock->sk_stamp is not thread-safe, from Deepa Dinamani.
10) Fix ptr_ring wrap during queue swap, from Cong Wang.
11) Missing shutdown callback in hinic driver, from Xue Chaojing.
12) Need to return NULL on error from ip6_neigh_lookup(), from Stefano
Brivio.
13) BPF out of bounds speculation fixes from Daniel Borkmann"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (57 commits)
ipv6: Consider sk_bound_dev_if when binding a socket to an address
ipv6: Fix dump of specific table with strict checking
bpf: add various test cases to selftests
bpf: prevent out of bounds speculation on pointer arithmetic
bpf: fix check_map_access smin_value test when pointer contains offset
bpf: restrict unknown scalars of mixed signed bounds for unprivileged
bpf: restrict stack pointer arithmetic for unprivileged
bpf: restrict map value pointer arithmetic for unprivileged
bpf: enable access to ax register also from verifier rewrite
bpf: move tmp variable into ax register in interpreter
bpf: move {prev_,}insn_idx into verifier env
isdn: fix kernel-infoleak in capi_unlocked_ioctl
ipv6: route: Fix return value of ip6_neigh_lookup() on neigh_create() error
net/hamradio/6pack: use mod_timer() to rearm timers
net-next/hinic:add shutdown callback
net: hns3: call hns3_nic_net_open() while doing HNAE3_UP_CLIENT
ip: validate header length on virtual device xmit
tap: call skb_probe_transport_header after setting skb->dev
ptr_ring: wrap back ->producer in __ptr_ring_swap_queue()
net: rds: remove unnecessary NULL check
...
Diffstat (limited to 'kernel/bpf/core.c')
-rw-r--r-- | kernel/bpf/core.c | 54 |
1 files changed, 37 insertions, 17 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 38de580abcc2..f908b9356025 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -54,6 +54,7 @@ #define DST regs[insn->dst_reg] #define SRC regs[insn->src_reg] #define FP regs[BPF_REG_FP] +#define AX regs[BPF_REG_AX] #define ARG1 regs[BPF_REG_ARG1] #define CTX regs[BPF_REG_CTX] #define IMM insn->imm @@ -857,6 +858,26 @@ static int bpf_jit_blind_insn(const struct bpf_insn *from, BUILD_BUG_ON(BPF_REG_AX + 1 != MAX_BPF_JIT_REG); BUILD_BUG_ON(MAX_BPF_REG + 1 != MAX_BPF_JIT_REG); + /* Constraints on AX register: + * + * AX register is inaccessible from user space. It is mapped in + * all JITs, and used here for constant blinding rewrites. It is + * typically "stateless" meaning its contents are only valid within + * the executed instruction, but not across several instructions. + * There are a few exceptions however which are further detailed + * below. + * + * Constant blinding is only used by JITs, not in the interpreter. + * The interpreter uses AX in some occasions as a local temporary + * register e.g. in DIV or MOD instructions. + * + * In restricted circumstances, the verifier can also use the AX + * register for rewrites as long as they do not interfere with + * the above cases! + */ + if (from->dst_reg == BPF_REG_AX || from->src_reg == BPF_REG_AX) + goto out; + if (from->imm == 0 && (from->code == (BPF_ALU | BPF_MOV | BPF_K) || from->code == (BPF_ALU64 | BPF_MOV | BPF_K))) { @@ -1188,7 +1209,6 @@ bool bpf_opcode_in_insntable(u8 code) */ static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack) { - u64 tmp; #define BPF_INSN_2_LBL(x, y) [BPF_##x | BPF_##y] = &&x##_##y #define BPF_INSN_3_LBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = &&x##_##y##_##z static const void *jumptable[256] = { @@ -1268,36 +1288,36 @@ select_insn: (*(s64 *) &DST) >>= IMM; CONT; ALU64_MOD_X: - div64_u64_rem(DST, SRC, &tmp); - DST = tmp; + div64_u64_rem(DST, SRC, &AX); + DST = AX; CONT; ALU_MOD_X: - tmp = (u32) DST; - DST = do_div(tmp, (u32) SRC); + AX = (u32) DST; + DST = do_div(AX, (u32) SRC); CONT; ALU64_MOD_K: - div64_u64_rem(DST, IMM, &tmp); - DST = tmp; + div64_u64_rem(DST, IMM, &AX); + DST = AX; CONT; ALU_MOD_K: - tmp = (u32) DST; - DST = do_div(tmp, (u32) IMM); + AX = (u32) DST; + DST = do_div(AX, (u32) IMM); CONT; ALU64_DIV_X: DST = div64_u64(DST, SRC); CONT; ALU_DIV_X: - tmp = (u32) DST; - do_div(tmp, (u32) SRC); - DST = (u32) tmp; + AX = (u32) DST; + do_div(AX, (u32) SRC); + DST = (u32) AX; CONT; ALU64_DIV_K: DST = div64_u64(DST, IMM); CONT; ALU_DIV_K: - tmp = (u32) DST; - do_div(tmp, (u32) IMM); - DST = (u32) tmp; + AX = (u32) DST; + do_div(AX, (u32) IMM); + DST = (u32) AX; CONT; ALU_END_TO_BE: switch (IMM) { @@ -1553,7 +1573,7 @@ STACK_FRAME_NON_STANDARD(___bpf_prog_run); /* jump table */ static unsigned int PROG_NAME(stack_size)(const void *ctx, const struct bpf_insn *insn) \ { \ u64 stack[stack_size / sizeof(u64)]; \ - u64 regs[MAX_BPF_REG]; \ + u64 regs[MAX_BPF_EXT_REG]; \ \ FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \ ARG1 = (u64) (unsigned long) ctx; \ @@ -1566,7 +1586,7 @@ static u64 PROG_NAME_ARGS(stack_size)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, \ const struct bpf_insn *insn) \ { \ u64 stack[stack_size / sizeof(u64)]; \ - u64 regs[MAX_BPF_REG]; \ + u64 regs[MAX_BPF_EXT_REG]; \ \ FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \ BPF_R1 = r1; \ |