From patchwork Tue Oct 8 09:14:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 13826014 X-Patchwork-Delegate: bpf@iogearbox.net Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (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 A341419994E for ; Tue, 8 Oct 2024 09:02:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728378155; cv=none; b=domqBPv7AuMde/TzJnkoBfbwVI11tb2RWIo633c/7QZeRwF9U3sypboazSk1UcfW67WHs8ZV6vF80pVcPp0nDhD0upsuuyRULYUEcy0kmpvGzA1Qu4XtcqOThD/Z33XiD8d6MheJtQlKrDt3YWwazWQl1D/1msr6sw/Gm03lxrc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728378155; c=relaxed/simple; bh=QLd+X2SvqaZ7PkkpneE9fez8BCTG0V4lLSMf7nduySU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PmZsA2Ck5hOSNoHjQZ5bYRCHlr8Nptun3VTvXsWRCxzx6MXzHTSQN0n43pKZhxM3uh/AO7EN0JANjnT2eFtr8Tkt7k8tc9Ww+P2AXVX71/Zzecpl2TOXLA4xFvkH/XXKm3Gj39iTR5GwVxHfvgtjTPWmWFSYWALdPciGj7/kF38= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.216]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4XN9570CXCz4f3jt1 for ; Tue, 8 Oct 2024 17:02:19 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id BA7B41A08FC for ; Tue, 8 Oct 2024 17:02:30 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.112.60]) by APP4 (Coremail) with SMTP id gCh0CgDH+sYd9QRnbOEHDg--.25681S15; Tue, 08 Oct 2024 17:02:30 +0800 (CST) From: Hou Tao To: bpf@vger.kernel.org Cc: Martin KaFai Lau , Alexei Starovoitov , Andrii Nakryiko , Eduard Zingerman , Song Liu , Hao Luo , Yonghong Song , Daniel Borkmann , KP Singh , Stanislav Fomichev , Jiri Olsa , John Fastabend , houtao1@huawei.com, xukuohai@huawei.com Subject: [PATCH bpf-next 11/16] bpf: Add bpf_mem_alloc_check_size() helper Date: Tue, 8 Oct 2024 17:14:56 +0800 Message-ID: <20241008091501.8302-12-houtao@huaweicloud.com> X-Mailer: git-send-email 2.45.0 In-Reply-To: <20241008091501.8302-1-houtao@huaweicloud.com> References: <20241008091501.8302-1-houtao@huaweicloud.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgDH+sYd9QRnbOEHDg--.25681S15 X-Coremail-Antispam: 1UD129KBjvJXoW7Aw17AF1Uuw18XFWUXw4xJFb_yoW5Jry5pF 47tr18AFs5JF48Wa42gw1xAas8Xw4vg3W7tay3XryUZF93GrnrWFs8try7XFnayrW5Aayx Jr1vgrWfCryUZ3DanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPvb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E 14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7 xfMcIj6xIIjxv20xvE14v26r106r15McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Y z7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1lc7CjxVAaw2 AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAq x4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r 43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Gr0_Xr1lIxAIcVC0I7IYx2IY6xkF 7I0E14v26r4UJVWxJr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14 v26r4j6F4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr1j6F4UJbIYCTnIWIevJa73UjIFyTuY vjxUoo7KUUUUU X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-Patchwork-Delegate: bpf@iogearbox.net From: Hou Tao Introduce bpf_mem_alloc_check_size() to check whether the allocation size exceeds the limitation for kmalloc-equivalent allocator. Because the upper limit for percpu allocation is LLIST_NODE_SZ bytes larger than non-percpu allocation, so an extra percpu argument is added to the helper. It will be used by the following patch to check whether the maximum size of variable-length key is valid. Signed-off-by: Hou Tao --- include/linux/bpf_mem_alloc.h | 3 +++ kernel/bpf/memalloc.c | 14 +++++++++++++- 2 files changed, 16 insertions(+), 1 deletion(-) diff --git a/include/linux/bpf_mem_alloc.h b/include/linux/bpf_mem_alloc.h index aaf004d94322..e45162ef59bb 100644 --- a/include/linux/bpf_mem_alloc.h +++ b/include/linux/bpf_mem_alloc.h @@ -33,6 +33,9 @@ int bpf_mem_alloc_percpu_init(struct bpf_mem_alloc *ma, struct obj_cgroup *objcg int bpf_mem_alloc_percpu_unit_init(struct bpf_mem_alloc *ma, int size); void bpf_mem_alloc_destroy(struct bpf_mem_alloc *ma); +/* Check the allocation size for kmalloc equivalent allocator */ +int bpf_mem_alloc_check_size(bool percpu, size_t size); + /* kmalloc/kfree equivalent: */ void *bpf_mem_alloc(struct bpf_mem_alloc *ma, size_t size); void bpf_mem_free(struct bpf_mem_alloc *ma, void *ptr); diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index b3858a76e0b3..146f5b57cfb1 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -35,6 +35,8 @@ */ #define LLIST_NODE_SZ sizeof(struct llist_node) +#define BPF_MEM_ALLOC_SIZE_MAX 4096 + /* similar to kmalloc, but sizeof == 8 bucket is gone */ static u8 size_index[24] __ro_after_init = { 3, /* 8 */ @@ -65,7 +67,7 @@ static u8 size_index[24] __ro_after_init = { static int bpf_mem_cache_idx(size_t size) { - if (!size || size > 4096) + if (!size || size > BPF_MEM_ALLOC_SIZE_MAX) return -1; if (size <= 192) @@ -1005,3 +1007,13 @@ void notrace *bpf_mem_cache_alloc_flags(struct bpf_mem_alloc *ma, gfp_t flags) return !ret ? NULL : ret + LLIST_NODE_SZ; } + +int bpf_mem_alloc_check_size(bool percpu, size_t size) +{ + /* The size of percpu allocation doesn't have LLIST_NODE_SZ overhead */ + if ((percpu && size > BPF_MEM_ALLOC_SIZE_MAX) || + (!percpu && size > BPF_MEM_ALLOC_SIZE_MAX - LLIST_NODE_SZ)) + return -E2BIG; + + return 0; +}