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| author | Jakub Kicinski <kuba@kernel.org> | 2024-05-02 22:05:13 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-05-02 22:06:25 +0300 |
| commit | e958da0ddbe831197a0023251880a4a09d5ba268 (patch) | |
| tree | eacded26f9563064a44fd1afe730493898adadb9 /kernel/bpf | |
| parent | dcc61472534e48a200262fd297ab21f8dd94d6cc (diff) | |
| parent | 545c494465d24b10a4370545ba213c0916f70b95 (diff) | |
| download | linux-e958da0ddbe831197a0023251880a4a09d5ba268.tar.xz | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.
Conflicts:
include/linux/filter.h
kernel/bpf/core.c
66e13b615a0c ("bpf: verifier: prevent userspace memory access")
d503a04f8bc0 ("bpf: Add support for certain atomics in bpf_arena to x86 JIT")
https://lore.kernel.org/all/20240429114939.210328b0@canb.auug.org.au/
No adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/core.c | 9 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 33 |
2 files changed, 40 insertions, 2 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 95c7fd093e55..192f67dd1f25 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -2970,6 +2970,15 @@ bool __weak bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena) return false; } +u64 __weak bpf_arch_uaddress_limit(void) +{ +#if defined(CONFIG_64BIT) && defined(CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE) + return TASK_SIZE; +#else + return 0; +#endif +} + /* Return TRUE if the JIT backend satisfies the following two conditions: * 1) JIT backend supports atomic_xchg() on pointer-sized words. * 2) Under the specific arch, the implementation of xchg() is the same diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 87ff414899cf..719c633e500a 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -18469,8 +18469,7 @@ static int resolve_pseudo_ldimm64(struct bpf_verifier_env *env) f = fdget(fd); map = __bpf_map_get(f); if (IS_ERR(map)) { - verbose(env, "fd %d is not pointing to valid bpf_map\n", - insn[0].imm); + verbose(env, "fd %d is not pointing to valid bpf_map\n", fd); return PTR_ERR(map); } @@ -19886,6 +19885,36 @@ static int do_misc_fixups(struct bpf_verifier_env *env) goto next_insn; } + /* Make it impossible to de-reference a userspace address */ + if (BPF_CLASS(insn->code) == BPF_LDX && + (BPF_MODE(insn->code) == BPF_PROBE_MEM || + BPF_MODE(insn->code) == BPF_PROBE_MEMSX)) { + struct bpf_insn *patch = &insn_buf[0]; + u64 uaddress_limit = bpf_arch_uaddress_limit(); + + if (!uaddress_limit) + goto next_insn; + + *patch++ = BPF_MOV64_REG(BPF_REG_AX, insn->src_reg); + if (insn->off) + *patch++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_AX, insn->off); + *patch++ = BPF_ALU64_IMM(BPF_RSH, BPF_REG_AX, 32); + *patch++ = BPF_JMP_IMM(BPF_JLE, BPF_REG_AX, uaddress_limit >> 32, 2); + *patch++ = *insn; + *patch++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1); + *patch++ = BPF_MOV64_IMM(insn->dst_reg, 0); + + cnt = patch - insn_buf; + new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt); + if (!new_prog) + return -ENOMEM; + + delta += cnt - 1; + env->prog = prog = new_prog; + insn = new_prog->insnsi + i + delta; + goto next_insn; + } + /* Implement LD_ABS and LD_IND with a rewrite, if supported by the program type. */ if (BPF_CLASS(insn->code) == BPF_LD && (BPF_MODE(insn->code) == BPF_ABS || |