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[34.244.49.215]) by smtp.gmail.com with ESMTPSA id c18-20020adfed92000000b0030ae499da59sm8882103wro.111.2023.06.05.00.40.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Jun 2023 00:40:26 -0700 (PDT) From: Puranjay Mohan To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, bpf@vger.kernel.org, kpsingh@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: puranjay12@gmail.com Subject: [PATCH bpf-next 1/3] bpf: make bpf_prog_pack allocator portable Date: Mon, 5 Jun 2023 07:40:22 +0000 Message-Id: <20230605074024.1055863-2-puranjay12@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230605074024.1055863-1-puranjay12@gmail.com> References: <20230605074024.1055863-1-puranjay12@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_ENVFROM_END_DIGIT, FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net The bpf_prog_pack allocator currently uses module_alloc() and module_memfree() to allocate and free memory. This is not portable because different architectures use different methods for allocating memory for BPF programs. Like ARM64 uses vmalloc()/vfree(). Use bpf_jit_alloc_exec() and bpf_jit_free_exec() for memory management in bpf_prog_pack allocator. Other architectures can override these with their implementation and will be able to use bpf_prog_pack directly. Signed-off-by: Puranjay Mohan Acked-by: Song Liu --- kernel/bpf/core.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 7421487422d4..2bc9092bf9be 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -860,7 +860,7 @@ static struct bpf_prog_pack *alloc_new_pack(bpf_jit_fill_hole_t bpf_fill_ill_ins GFP_KERNEL); if (!pack) return NULL; - pack->ptr = module_alloc(BPF_PROG_PACK_SIZE); + pack->ptr = bpf_jit_alloc_exec(BPF_PROG_PACK_SIZE); if (!pack->ptr) { kfree(pack); return NULL; @@ -884,7 +884,7 @@ void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns) mutex_lock(&pack_mutex); if (size > BPF_PROG_PACK_SIZE) { size = round_up(size, PAGE_SIZE); - ptr = module_alloc(size); + ptr = bpf_jit_alloc_exec(size); if (ptr) { bpf_fill_ill_insns(ptr, size); set_vm_flush_reset_perms(ptr); @@ -922,7 +922,7 @@ void bpf_prog_pack_free(struct bpf_binary_header *hdr) mutex_lock(&pack_mutex); if (hdr->size > BPF_PROG_PACK_SIZE) { - module_memfree(hdr); + bpf_jit_free_exec(hdr); goto out; } @@ -946,7 +946,7 @@ void bpf_prog_pack_free(struct bpf_binary_header *hdr) if (bitmap_find_next_zero_area(pack->bitmap, BPF_PROG_CHUNK_COUNT, 0, BPF_PROG_CHUNK_COUNT, 0) == 0) { list_del(&pack->list); - module_memfree(pack->ptr); + bpf_jit_free_exec(pack->ptr); kfree(pack); } out: From patchwork Mon Jun 5 07:40:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Puranjay Mohan X-Patchwork-Id: 13267031 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D03911CA4 for ; Mon, 5 Jun 2023 07:40:30 +0000 (UTC) Received: from mail-wm1-x333.google.com (mail-wm1-x333.google.com [IPv6:2a00:1450:4864:20::333]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 75B00D3; Mon, 5 Jun 2023 00:40:28 -0700 (PDT) Received: by mail-wm1-x333.google.com with SMTP id 5b1f17b1804b1-3f6da07ff00so45672305e9.3; Mon, 05 Jun 2023 00:40:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1685950827; x=1688542827; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=IkzqYxL73s22EAwsna++GGXRkm1HvzsrQXeSnzKLJ6M=; b=ad1sTI8nqnhQ4S/1WnIPW6zm48etDauqxoNS4yAm8F/DkP+AJY3rZU6ft/MBECBmMb 8F29zfFuogHVFdyX+p0h627jFsihUhI+MZrV4E4xFEuBWhoo0iFHN7HEUNxT79PjePaz +OscpeOPWhNmq9mW15hMqAabb4Fm1MjCFVWwut+poRj6rFEvyyXhz9ey5BpE6FTxpnrR QHqIXTmpLEefs/M+wfYU967NOJITwOMCfXsOGa+tn8EA457L1tuFaRi6+MoeqHipcZmw IlKuB8RufCWHnEqiToTsqgaZzPE30xdn6xutUufEjbRcTpN07qItho2sPv/8hxbKlYxK Fipg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685950827; x=1688542827; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=IkzqYxL73s22EAwsna++GGXRkm1HvzsrQXeSnzKLJ6M=; b=ImvDZRSEIXrA/ZdqOvLVubkN7hG7Od92b+QNcatLglVqDmU+GBL3sAKS+4XXhIg9d6 urSUw+mfpKtcdk5QUZDC7+7SGhBaCU/z5FLTxYQSXJrbFj4NqDHYkN5Isi9JsWNFegzV wiESdEWxnUTDGzm39eWLGwovy7F6Wimbodzuddw8AIoBS5un2L3qQYtlB1JafgiE11Kk 4NF+XcCHn6oB9vy2SLtx8EegZGI+WkrKzBxSxIwnUYsw0vuB+ZkBSyhwfPTEL3vopW53 PYSD7FVd9bwokk/NkRxeOTiYtwO7uRy0xgrQ3tIdAPeW/RrZF9hIt3Y5nb9BDxk6e6TV XLeA== X-Gm-Message-State: AC+VfDz94mUR1jj0BU7Lk9CjIoxuWbTQJFJFpdj3qr5hJCBXuW+IQypc DghgSHqtZM2nHgiJjqzOhVA= X-Google-Smtp-Source: ACHHUZ7Ls9cXd9bOy8NVrhksZPkskca3CwSJJZLtxIsyFgHq0GzJNJ2CJ6bYNnwlMBoG7rmQWQMQgg== X-Received: by 2002:a7b:ca46:0:b0:3f1:789d:ad32 with SMTP id m6-20020a7bca46000000b003f1789dad32mr8195807wml.11.1685950826769; Mon, 05 Jun 2023 00:40:26 -0700 (PDT) Received: from ip-172-31-22-112.eu-west-1.compute.internal (ec2-34-244-49-215.eu-west-1.compute.amazonaws.com. [34.244.49.215]) by smtp.gmail.com with ESMTPSA id c18-20020adfed92000000b0030ae499da59sm8882103wro.111.2023.06.05.00.40.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Jun 2023 00:40:26 -0700 (PDT) From: Puranjay Mohan To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, bpf@vger.kernel.org, kpsingh@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: puranjay12@gmail.com Subject: [PATCH bpf-next 2/3] arm64: patching: Add aarch64_insn_copy() Date: Mon, 5 Jun 2023 07:40:23 +0000 Message-Id: <20230605074024.1055863-3-puranjay12@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230605074024.1055863-1-puranjay12@gmail.com> References: <20230605074024.1055863-1-puranjay12@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_ENVFROM_END_DIGIT, FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net This will be used by BPF JIT compiler to dump JITed binary to a RX huge page, and thus allow multiple BPF programs sharing the a huge (2MB) page. The bpf_prog_pack allocator that implements the above feature allocates a RX/RW buffer pair. The JITed code is written to the RW buffer and then this function will be used to copy the code from RW to RX buffer. Signed-off-by: Puranjay Mohan Acked-by: Song Liu --- arch/arm64/include/asm/patching.h | 1 + arch/arm64/kernel/patching.c | 39 +++++++++++++++++++++++++++++++ 2 files changed, 40 insertions(+) diff --git a/arch/arm64/include/asm/patching.h b/arch/arm64/include/asm/patching.h index 68908b82b168..dba9eb392bf1 100644 --- a/arch/arm64/include/asm/patching.h +++ b/arch/arm64/include/asm/patching.h @@ -8,6 +8,7 @@ int aarch64_insn_read(void *addr, u32 *insnp); int aarch64_insn_write(void *addr, u32 insn); int aarch64_insn_write_literal_u64(void *addr, u64 val); +void *aarch64_insn_copy(void *addr, const void *opcode, size_t len); int aarch64_insn_patch_text_nosync(void *addr, u32 insn); int aarch64_insn_patch_text(void *addrs[], u32 insns[], int cnt); diff --git a/arch/arm64/kernel/patching.c b/arch/arm64/kernel/patching.c index b4835f6d594b..48c710f6a1ff 100644 --- a/arch/arm64/kernel/patching.c +++ b/arch/arm64/kernel/patching.c @@ -105,6 +105,45 @@ noinstr int aarch64_insn_write_literal_u64(void *addr, u64 val) return ret; } +/** + * aarch64_insn_copy - Copy instructions into (an unused part of) RX memory + * @addr: address to modify + * @opcode: source of the copy + * @len: length to copy + * + * Useful for JITs to dump new code blocks into unused regions of RX memory. + */ +noinstr void *aarch64_insn_copy(void *addr, const void *opcode, size_t len) +{ + unsigned long flags; + size_t patched = 0; + size_t size; + void *waddr; + void *dst; + int ret; + + raw_spin_lock_irqsave(&patch_lock, flags); + + while (patched < len) { + dst = addr + patched; + size = min_t(size_t, PAGE_SIZE - offset_in_page(dst), + len - patched); + + waddr = patch_map(dst, FIX_TEXT_POKE0); + ret = copy_to_kernel_nofault(waddr, opcode + patched, size); + patch_unmap(FIX_TEXT_POKE0); + + if (ret < 0) { + raw_spin_unlock_irqrestore(&patch_lock, flags); + return NULL; + } + patched += size; + } + raw_spin_unlock_irqrestore(&patch_lock, flags); + + return addr; +} + int __kprobes aarch64_insn_patch_text_nosync(void *addr, u32 insn) { u32 *tp = addr; From patchwork Mon Jun 5 07:40:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Puranjay Mohan X-Patchwork-Id: 13267032 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D407911CA1 for ; Mon, 5 Jun 2023 07:40:30 +0000 (UTC) Received: from mail-wr1-x42b.google.com (mail-wr1-x42b.google.com [IPv6:2a00:1450:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 084D1BD; Mon, 5 Jun 2023 00:40:29 -0700 (PDT) Received: by mail-wr1-x42b.google.com with SMTP id ffacd0b85a97d-30af0aa4812so3963052f8f.1; Mon, 05 Jun 2023 00:40:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1685950827; x=1688542827; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=U7uLu0MKoT2YcSWwQmWFrEpyEOBt5snH1w0w+98A6AE=; b=Fd+8ZiArtALO8L+RipgFoGryrvHn7aJdM+c71cEUaFe8WfAEZ6lgy6p4vBq2GEJ+Rr HiP7oQvJecxPZYwzaIuV2kqp/4UpNHlwwM/R1a1bcPALoJBjY3mZPzFOrvQE8AI0DK+T pQe9AfMue8cdVvJFzyaVUQS/0f/67AFrUeahlUbZ8ke6675YAEJY8rmrQN9YTf/kD79D L800uulHIHdoJE3F33NV+yY9eaWmMlaBLTkWbspCOPf3OFtxl2OwIBmBfgFVTCF1GWdw +6VgCl58xSBkJl87ubVaCA5rQAL085z8Vi3CbKQtK4KYdbv5XFe2mr/MXZaE8B3hVoSe YOSg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685950827; x=1688542827; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=U7uLu0MKoT2YcSWwQmWFrEpyEOBt5snH1w0w+98A6AE=; b=OGT/92ewv9ZQMTT68BfEJw4I19Bu4RSnb1SrDW4X7fPMqx742BGNl4N7YUmGU8rthp rH2iNtcaNDlPDbwoL80t/rO4FqxFqjCrehCDGyrg5gbfO8op1mLJboEVKZ0veKKonjUA TRtZqZXaExPEkOSMgoAfakiRH+0vM7O4IiIw+8E3LQVPHPO3rWMr5C4YbvsfH3mFDdke 0rmXRIMI12mlsrh3Poa6lrNgcIyoh5nGNKVe9oAzHWlccO6hd16ePyeRvBfnWdrlhKzB F5g5r7dCizqddQqd4caDL+DHyijt6srmUcWQqhjq90WMLhGd3tqi54w1jGTTAZPvKbRb OM9A== X-Gm-Message-State: AC+VfDxFt03BtBTWeCx+RbSkTA8/FA2OjTtljlG86tBlmEz6utO9klPl 4WnaHsSUIW5hBJsev7GI7eU= X-Google-Smtp-Source: ACHHUZ5Db5vZjZItfR09bz49VUXwkGlA7pPtWGZM69tBAdXIUMUY/apMk1UlRmXTQKopJ/U4OGhBvg== X-Received: by 2002:a05:6000:194e:b0:307:c471:7b38 with SMTP id e14-20020a056000194e00b00307c4717b38mr4119865wry.59.1685950827352; Mon, 05 Jun 2023 00:40:27 -0700 (PDT) Received: from ip-172-31-22-112.eu-west-1.compute.internal (ec2-34-244-49-215.eu-west-1.compute.amazonaws.com. [34.244.49.215]) by smtp.gmail.com with ESMTPSA id c18-20020adfed92000000b0030ae499da59sm8882103wro.111.2023.06.05.00.40.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Jun 2023 00:40:27 -0700 (PDT) From: Puranjay Mohan To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, bpf@vger.kernel.org, kpsingh@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: puranjay12@gmail.com Subject: [PATCH bpf-next 3/3] bpf, arm64: use bpf_jit_binary_pack_alloc Date: Mon, 5 Jun 2023 07:40:24 +0000 Message-Id: <20230605074024.1055863-4-puranjay12@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230605074024.1055863-1-puranjay12@gmail.com> References: <20230605074024.1055863-1-puranjay12@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_ENVFROM_END_DIGIT, FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net Use bpf_jit_binary_pack_alloc for memory management of JIT binaries in ARM64 BPF JIT. The bpf_jit_binary_pack_alloc creates a pair of RW and RX buffers. The JIT writes the program into the RW buffer. When the JIT is done, the program is copied to the final ROX buffer with bpf_jit_binary_pack_finalize. Implement bpf_arch_text_copy() and bpf_arch_text_invalidate() for ARM64 JIT as these functions are required by bpf_jit_binary_pack allocator. Signed-off-by: Puranjay Mohan --- arch/arm64/net/bpf_jit_comp.c | 119 +++++++++++++++++++++++++++++----- 1 file changed, 102 insertions(+), 17 deletions(-) diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index 145b540ec34f..ee9414cadea8 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -76,6 +76,7 @@ struct jit_ctx { int *offset; int exentry_idx; __le32 *image; + __le32 *ro_image; u32 stack_size; int fpb_offset; }; @@ -205,6 +206,20 @@ static void jit_fill_hole(void *area, unsigned int size) *ptr++ = cpu_to_le32(AARCH64_BREAK_FAULT); } +int bpf_arch_text_invalidate(void *dst, size_t len) +{ + __le32 *ptr; + int ret; + + for (ptr = dst; len >= sizeof(u32); len -= sizeof(u32)) { + ret = aarch64_insn_patch_text_nosync(ptr++, AARCH64_BREAK_FAULT); + if (ret) + return ret; + } + + return 0; +} + static inline int epilogue_offset(const struct jit_ctx *ctx) { int to = ctx->epilogue_offset; @@ -701,7 +716,8 @@ static int add_exception_handler(const struct bpf_insn *insn, struct jit_ctx *ctx, int dst_reg) { - off_t offset; + off_t ins_offset; + off_t fixup_offset; unsigned long pc; struct exception_table_entry *ex; @@ -717,12 +733,11 @@ static int add_exception_handler(const struct bpf_insn *insn, return -EINVAL; ex = &ctx->prog->aux->extable[ctx->exentry_idx]; - pc = (unsigned long)&ctx->image[ctx->idx - 1]; + pc = (unsigned long)&ctx->ro_image[ctx->idx - 1]; - offset = pc - (long)&ex->insn; - if (WARN_ON_ONCE(offset >= 0 || offset < INT_MIN)) + ins_offset = pc - (long)&ex->insn; + if (WARN_ON_ONCE(ins_offset >= 0 || ins_offset < INT_MIN)) return -ERANGE; - ex->insn = offset; /* * Since the extable follows the program, the fixup offset is always @@ -732,11 +747,20 @@ static int add_exception_handler(const struct bpf_insn *insn, * modifying the upper bits because the table is already sorted, and * isn't part of the main exception table. */ - offset = (long)&ex->fixup - (pc + AARCH64_INSN_SIZE); - if (!FIELD_FIT(BPF_FIXUP_OFFSET_MASK, offset)) + fixup_offset = (long)&ex->fixup - (pc + AARCH64_INSN_SIZE); + if (!FIELD_FIT(BPF_FIXUP_OFFSET_MASK, fixup_offset)) return -ERANGE; - ex->fixup = FIELD_PREP(BPF_FIXUP_OFFSET_MASK, offset) | + /* + * The offsets above have been calculated using the RO+X buffer but we + * need to use the R/W buffer for writes. + * switch ex to rw buffer for writing. + */ + ex = (void *)ctx->image + ((void *)ex - (void *)ctx->ro_image); + + ex->insn = ins_offset; + + ex->fixup = FIELD_PREP(BPF_FIXUP_OFFSET_MASK, fixup_offset) | FIELD_PREP(BPF_FIXUP_REG_MASK, dst_reg); ex->type = EX_TYPE_BPF; @@ -1446,6 +1470,7 @@ static inline void bpf_flush_icache(void *start, void *end) struct arm64_jit_data { struct bpf_binary_header *header; + struct bpf_binary_header *rw_header; u8 *image; struct jit_ctx ctx; }; @@ -1454,6 +1479,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) { int image_size, prog_size, extable_size, extable_align, extable_offset; struct bpf_prog *tmp, *orig_prog = prog; + struct bpf_binary_header *rw_header; struct bpf_binary_header *header; struct arm64_jit_data *jit_data; bool was_classic = bpf_prog_was_classic(prog); @@ -1461,6 +1487,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) bool extra_pass = false; struct jit_ctx ctx; u8 *image_ptr; + u8 *rw_image_ptr; if (!prog->jit_requested) return orig_prog; @@ -1489,6 +1516,9 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) ctx = jit_data->ctx; image_ptr = jit_data->image; header = jit_data->header; + rw_header = jit_data->rw_header; + rw_image_ptr = (void *)rw_header + ((void *)image_ptr + - (void *)header); extra_pass = true; prog_size = sizeof(u32) * ctx.idx; goto skip_init_ctx; @@ -1533,8 +1563,9 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) /* also allocate space for plt target */ extable_offset = round_up(prog_size + PLT_TARGET_SIZE, extable_align); image_size = extable_offset + extable_size; - header = bpf_jit_binary_alloc(image_size, &image_ptr, - sizeof(u32), jit_fill_hole); + header = bpf_jit_binary_pack_alloc(image_size, &image_ptr, sizeof(u32), + &rw_header, &rw_image_ptr, + jit_fill_hole); if (header == NULL) { prog = orig_prog; goto out_off; @@ -1542,19 +1573,24 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) /* 2. Now, the actual pass. */ - ctx.image = (__le32 *)image_ptr; if (extable_size) prog->aux->extable = (void *)image_ptr + extable_offset; skip_init_ctx: + /* + * Use the rw_image_ptr for writing the JITed instructions. + * Save the read only image_ptr in ctx because it will be used to + * calculate offsets for filling out the exception table later. + */ + ctx.image = (__le32 *)rw_image_ptr; + ctx.ro_image = (__le32 *)image_ptr; ctx.idx = 0; ctx.exentry_idx = 0; build_prologue(&ctx, was_classic); if (build_body(&ctx, extra_pass)) { - bpf_jit_binary_free(header); prog = orig_prog; - goto out_off; + goto out_free_hdr; } build_epilogue(&ctx); @@ -1562,32 +1598,42 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) /* 3. Extra pass to validate JITed code. */ if (validate_ctx(&ctx)) { - bpf_jit_binary_free(header); prog = orig_prog; - goto out_off; + goto out_free_hdr; } /* And we're done. */ if (bpf_jit_enable > 1) bpf_jit_dump(prog->len, prog_size, 2, ctx.image); + /* + * As the JITed instructions have been written to the R/W buffer, we can + * move ctx.image back to the RO+X buffer from where the BPF program + * will run. bpf_jit_binary_pack_finalize() will copy the instructions + * from the R/W buffer to the RO+X buffer. + */ + ctx.image = (__le32 *)image_ptr; bpf_flush_icache(header, ctx.image + ctx.idx); if (!prog->is_func || extra_pass) { if (extra_pass && ctx.idx != jit_data->ctx.idx) { pr_err_once("multi-func JIT bug %d != %d\n", ctx.idx, jit_data->ctx.idx); - bpf_jit_binary_free(header); prog->bpf_func = NULL; prog->jited = 0; prog->jited_len = 0; + goto out_free_hdr; + } + if (WARN_ON(bpf_jit_binary_pack_finalize(prog, header, + rw_header))) { + header = NULL; goto out_off; } - bpf_jit_binary_lock_ro(header); } else { jit_data->ctx = ctx; jit_data->image = image_ptr; jit_data->header = header; + jit_data->rw_header = rw_header; } prog->bpf_func = (void *)ctx.image; prog->jited = 1; @@ -1610,6 +1656,14 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) bpf_jit_prog_release_other(prog, prog == orig_prog ? tmp : orig_prog); return prog; + +out_free_hdr: + if (header) { + bpf_arch_text_copy(&header->size, &rw_header->size, + sizeof(rw_header->size)); + bpf_jit_binary_pack_free(header, rw_header); + } + goto out_off; } bool bpf_jit_supports_kfunc_call(void) @@ -1617,6 +1671,13 @@ bool bpf_jit_supports_kfunc_call(void) return true; } +void *bpf_arch_text_copy(void *dst, void *src, size_t len) +{ + if (aarch64_insn_copy(dst, src, len) == NULL) + return ERR_PTR(-EINVAL); + return dst; +} + u64 bpf_jit_alloc_exec_limit(void) { return VMALLOC_END - VMALLOC_START; @@ -2221,3 +2282,27 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type poke_type, return ret; } + +void bpf_jit_free(struct bpf_prog *prog) +{ + if (prog->jited) { + struct arm64_jit_data *jit_data = prog->aux->jit_data; + struct bpf_binary_header *hdr; + + /* + * If we fail the final pass of JIT (from jit_subprogs), + * the program may not be finalized yet. Call finalize here + * before freeing it. + */ + if (jit_data) { + bpf_jit_binary_pack_finalize(prog, jit_data->header, + jit_data->rw_header); + kfree(jit_data); + } + hdr = bpf_jit_binary_pack_hdr(prog); + bpf_jit_binary_pack_free(hdr, NULL); + WARN_ON_ONCE(!bpf_prog_kallsyms_verify_off(prog)); + } + + bpf_prog_unlock_free(prog); +}