diff options
| -rw-r--r-- | arch/arm64/net/bpf_jit_comp.c | 39 |
1 files changed, 30 insertions, 9 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index 7ae33545535b..71088952ed27 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -19,12 +19,13 @@ #define pr_fmt(fmt) "bpf_jit: " fmt #include <linux/filter.h> -#include <linux/moduleloader.h> #include <linux/printk.h> #include <linux/skbuff.h> #include <linux/slab.h> + #include <asm/byteorder.h> #include <asm/cacheflush.h> +#include <asm/debug-monitors.h> #include "bpf_jit.h" @@ -119,6 +120,14 @@ static inline int bpf2a64_offset(int bpf_to, int bpf_from, return to - from; } +static void jit_fill_hole(void *area, unsigned int size) +{ + u32 *ptr; + /* We are guaranteed to have aligned memory. */ + for (ptr = area; size >= sizeof(u32); size -= sizeof(u32)) + *ptr++ = cpu_to_le32(AARCH64_BREAK_FAULT); +} + static inline int epilogue_offset(const struct jit_ctx *ctx) { int to = ctx->offset[ctx->prog->len - 1]; @@ -613,8 +622,10 @@ void bpf_jit_compile(struct bpf_prog *prog) void bpf_int_jit_compile(struct bpf_prog *prog) { + struct bpf_binary_header *header; struct jit_ctx ctx; int image_size; + u8 *image_ptr; if (!bpf_jit_enable) return; @@ -636,23 +647,25 @@ void bpf_int_jit_compile(struct bpf_prog *prog) goto out; build_prologue(&ctx); - build_epilogue(&ctx); /* Now we know the actual image size. */ image_size = sizeof(u32) * ctx.idx; - ctx.image = module_alloc(image_size); - if (unlikely(ctx.image == NULL)) + header = bpf_jit_binary_alloc(image_size, &image_ptr, + sizeof(u32), jit_fill_hole); + if (header == NULL) goto out; /* 2. Now, the actual pass. */ + ctx.image = (u32 *)image_ptr; ctx.idx = 0; + build_prologue(&ctx); ctx.body_offset = ctx.idx; if (build_body(&ctx)) { - module_free(NULL, ctx.image); + bpf_jit_binary_free(header); goto out; } @@ -663,17 +676,25 @@ void bpf_int_jit_compile(struct bpf_prog *prog) bpf_jit_dump(prog->len, image_size, 2, ctx.image); bpf_flush_icache(ctx.image, ctx.image + ctx.idx); + + set_memory_ro((unsigned long)header, header->pages); prog->bpf_func = (void *)ctx.image; prog->jited = 1; - out: kfree(ctx.offset); } void bpf_jit_free(struct bpf_prog *prog) { - if (prog->jited) - module_free(NULL, prog->bpf_func); + unsigned long addr = (unsigned long)prog->bpf_func & PAGE_MASK; + struct bpf_binary_header *header = (void *)addr; + + if (!prog->jited) + goto free_filter; + + set_memory_rw(addr, header->pages); + bpf_jit_binary_free(header); - kfree(prog); +free_filter: + bpf_prog_unlock_free(prog); } |