From nobody Thu Apr 2 09:27:35 2026 Received: from out-178.mta0.migadu.com (out-178.mta0.migadu.com [91.218.175.178]) (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 D843D314B61 for ; Mon, 16 Feb 2026 15:06:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.178 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254363; cv=none; b=Vf9vD0R7Pt443MOQVJ68I8k9KbD3kCr20kJouHicxCrZR85+oWkaiQwPhP/c9G9A4upEoFfU0TEfryXZ4o162zoM0f13mmiZ51N+9nceExGnyp+WYwfZHPZGMu2rH+z/eP5e5CBhooi56pkcwwpxo4CuLihx+PLmv1Wnckk5y2Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254363; c=relaxed/simple; bh=LjfH1DlLA8gEeHwZbcUBKWf2hLkFhHejBbxMzhqfH6Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pDb6fS9HhTRlgA2Suwmd/hZAK1e3LCbz/P6qok6OiRjqQv5JYMOIAVcipdzT4fc3v6qORyK60GOCrI1x493LGa83pENqNmZ4u9WoJOksa4b0cTa/LgzliUzrB3BSLmjyWnoaqo9cEeLYNf/UbpDJ3cfWysSBNkiDCgbmP9Df39s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=bXnESz5F; arc=none smtp.client-ip=91.218.175.178 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="bXnESz5F" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771254358; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Q1AT3YeJPTEMZKh/Vk3atwGdvuDg0mgHwA9lNLKly18=; b=bXnESz5Fq61/Uuat44DsxV7yjG4P0q4ltf7t3gHK2qHWij7GMzDG/VJ63EQH1ju9bS1BGy 5V+fShRl4Jl2js8NhjYklM59nszucystEqnKIXZ94G6iRqme6TID9jFzfueJl4NhZdTdVI j6+cbe7yznHz4zlK+J00y2gCPvR5i/4= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v11 1/8] bpf: Extend BPF syscall with common attributes support Date: Mon, 16 Feb 2026 23:04:38 +0800 Message-ID: <20260216150445.68278-2-leon.hwang@linux.dev> In-Reply-To: <20260216150445.68278-1-leon.hwang@linux.dev> References: <20260216150445.68278-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" Add generic BPF syscall support for passing common attributes. The initial set of common attributes includes: 1. 'log_buf': User-provided buffer for storing logs. 2. 'log_size': Size of the log buffer. 3. 'log_level': Log verbosity level. 4. 'log_true_size': Actual log size reported by kernel. The common-attribute pointer and its size are passed as the 4th and 5th syscall arguments. A new command bit, 'BPF_COMMON_ATTRS' ('1 << 16'), indicates that common attributes are supplied. This commit adds syscall and uapi plumbing. Command-specific handling is added in follow-up patches. Signed-off-by: Leon Hwang --- include/linux/syscalls.h | 3 ++- include/uapi/linux/bpf.h | 8 ++++++++ kernel/bpf/syscall.c | 25 +++++++++++++++++++++---- tools/include/uapi/linux/bpf.h | 8 ++++++++ 4 files changed, 39 insertions(+), 5 deletions(-) diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 02bd6ddb6278..f4848c64872f 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -936,7 +936,8 @@ asmlinkage long sys_seccomp(unsigned int op, unsigned i= nt flags, asmlinkage long sys_getrandom(char __user *buf, size_t count, unsigned int flags); asmlinkage long sys_memfd_create(const char __user *uname_ptr, unsigned in= t flags); -asmlinkage long sys_bpf(int cmd, union bpf_attr __user *attr, unsigned int= size); +asmlinkage long sys_bpf(int cmd, union bpf_attr __user *attr, unsigned int= size, + struct bpf_common_attr __user *attr_common, unsigned int size_common); asmlinkage long sys_execveat(int dfd, const char __user *filename, const char __user *const __user *argv, const char __user *const __user *envp, int flags); diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index c8d400b7680a..b2126c9641ec 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -994,6 +994,7 @@ enum bpf_cmd { BPF_PROG_STREAM_READ_BY_FD, BPF_PROG_ASSOC_STRUCT_OPS, __MAX_BPF_CMD, + BPF_COMMON_ATTRS =3D 1 << 16, /* Indicate carrying syscall common attrs. = */ }; =20 enum bpf_map_type { @@ -1500,6 +1501,13 @@ struct bpf_stack_build_id { }; }; =20 +struct bpf_common_attr { + __u64 log_buf; + __u32 log_size; + __u32 log_level; + __u32 log_true_size; +}; + #define BPF_OBJ_NAME_LEN 16U =20 enum { diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index dd89bf809772..e7ab87908189 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -6187,8 +6187,10 @@ static int prog_assoc_struct_ops(union bpf_attr *att= r) return ret; } =20 -static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size) +static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size, + bpfptr_t uattr_common, unsigned int size_common) { + struct bpf_common_attr attr_common; union bpf_attr attr; int err; =20 @@ -6202,6 +6204,20 @@ static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uatt= r, unsigned int size) if (copy_from_bpfptr(&attr, uattr, size) !=3D 0) return -EFAULT; =20 + memset(&attr_common, 0, sizeof(attr_common)); + if (cmd & BPF_COMMON_ATTRS) { + err =3D bpf_check_uarg_tail_zero(uattr_common, sizeof(attr_common), size= _common); + if (err) + return err; + + cmd &=3D ~BPF_COMMON_ATTRS; + size_common =3D min_t(u32, size_common, sizeof(attr_common)); + if (copy_from_bpfptr(&attr_common, uattr_common, size_common) !=3D 0) + return -EFAULT; + } else { + size_common =3D 0; + } + err =3D security_bpf(cmd, &attr, size, uattr.is_kernel); if (err < 0) return err; @@ -6337,9 +6353,10 @@ static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uatt= r, unsigned int size) return err; } =20 -SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned in= t, size) +SYSCALL_DEFINE5(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned in= t, size, + struct bpf_common_attr __user *, uattr_common, unsigned int, size_common) { - return __sys_bpf(cmd, USER_BPFPTR(uattr), size); + return __sys_bpf(cmd, USER_BPFPTR(uattr), size, USER_BPFPTR(uattr_common)= , size_common); } =20 static bool syscall_prog_is_valid_access(int off, int size, @@ -6370,7 +6387,7 @@ BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, a= ttr, u32, attr_size) default: return -EINVAL; } - return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size); + return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size, KERNEL_BPFPTR(NULL)= , 0); } =20 =20 diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 5e38b4887de6..c4934c2370fd 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -994,6 +994,7 @@ enum bpf_cmd { BPF_PROG_STREAM_READ_BY_FD, BPF_PROG_ASSOC_STRUCT_OPS, __MAX_BPF_CMD, + BPF_COMMON_ATTRS =3D 1 << 16, /* Indicate carrying syscall common attrs. = */ }; =20 enum bpf_map_type { @@ -1500,6 +1501,13 @@ struct bpf_stack_build_id { }; }; =20 +struct bpf_common_attr { + __u64 log_buf; + __u32 log_size; + __u32 log_level; + __u32 log_true_size; +}; + #define BPF_OBJ_NAME_LEN 16U =20 enum { --=20 2.52.0 From nobody Thu Apr 2 09:27:35 2026 Received: from out-173.mta0.migadu.com (out-173.mta0.migadu.com [91.218.175.173]) (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 F2B3C3161B1 for ; Mon, 16 Feb 2026 15:06:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254376; cv=none; b=J5jX/pot537GzaNqNjDCdaZIgwcQVAeC9TlZr3TP62KNg/XpriP4JWkIHjgW4jCb0kNXmpYcwU4oMeSd+jlGGc2FQOYipObs8ZheWp6UhFNpUrVoJOsZuuFjgCprjSUc/uR8uJd/aIjDio+V7k25HbirAskt5RDJLEMOQE0EZkM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254376; c=relaxed/simple; bh=+rpFprJBjV+nkGhaF+kJyg6eUDCUKexcnfBuSKsRM0U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nKTipGSTwlSE4hYpZQqtF1cG9wOjEtvIo1/M8DTktUIUkM7xQizaINsEF3YSpSB8EjUHvy3eF0C42e5SEqZGvt3/IUARSM4gq/tpibTrs1G9X4YvfWKp4xoNmvncHOQlWv9Ah6gceWMignZNSW2pdAjYtQNAI4DV2opQCkN6/+0= ARC-Authentication-Results: i=1; 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DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771254372; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=z226B2XpSmq8CSurWwANapKEljmLoPyyQ4nyb6ASTzE=; b=P+YhlP9+zLY5jgc+mxcRPgEtZeahM2kPCrCsbholOWeQNj3O9LOSwL8D5mwkBcD0kgoLh5 8zurFu6IjPf5oW0EZ846rlRBEZYtYDbBC2Kpewv077i3tEq0b5QOmt8EyWWv0aVCNE77bc wjAeFN7gvA9IrqwD3V6GpQZfHlVcQLI= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v11 2/8] libbpf: Add support for extended BPF syscall Date: Mon, 16 Feb 2026 23:04:39 +0800 Message-ID: <20260216150445.68278-3-leon.hwang@linux.dev> In-Reply-To: <20260216150445.68278-1-leon.hwang@linux.dev> References: <20260216150445.68278-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" To support the extended BPF syscall introduced in the previous commit, introduce the following internal APIs: * 'sys_bpf_ext()' * 'sys_bpf_ext_fd()' They wrap the raw 'syscall()' interface to support passing extended attributes. * 'probe_sys_bpf_ext()' Check whether current kernel supports the BPF syscall common attributes. Acked-by: Andrii Nakryiko Signed-off-by: Leon Hwang --- tools/lib/bpf/bpf.c | 36 +++++++++++++++++++++++++++++++++ tools/lib/bpf/features.c | 8 ++++++++ tools/lib/bpf/libbpf_internal.h | 3 +++ 3 files changed, 47 insertions(+) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 5846de364209..9d8740761b7a 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -69,6 +69,42 @@ static inline __u64 ptr_to_u64(const void *ptr) return (__u64) (unsigned long) ptr; } =20 +static inline int sys_bpf_ext(enum bpf_cmd cmd, union bpf_attr *attr, + unsigned int size, + struct bpf_common_attr *attr_common, + unsigned int size_common) +{ + cmd =3D attr_common ? (cmd | BPF_COMMON_ATTRS) : (cmd & ~BPF_COMMON_ATTRS= ); + return syscall(__NR_bpf, cmd, attr, size, attr_common, size_common); +} + +static inline int sys_bpf_ext_fd(enum bpf_cmd cmd, union bpf_attr *attr, + unsigned int size, + struct bpf_common_attr *attr_common, + unsigned int size_common) +{ + int fd; + + fd =3D sys_bpf_ext(cmd, attr, size, attr_common, size_common); + return ensure_good_fd(fd); +} + +int probe_sys_bpf_ext(void) +{ + const size_t attr_sz =3D offsetofend(union bpf_attr, prog_token_fd); + union bpf_attr attr; + int fd; + + memset(&attr, 0, attr_sz); + fd =3D syscall(__NR_bpf, BPF_PROG_LOAD | BPF_COMMON_ATTRS, &attr, attr_sz= , NULL, + sizeof(struct bpf_common_attr)); + if (fd >=3D 0) { + close(fd); + return -EINVAL; + } + return errno =3D=3D EFAULT ? 1 : 0; +} + static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr, unsigned int size) { diff --git a/tools/lib/bpf/features.c b/tools/lib/bpf/features.c index b842b83e2480..e0d646a9e233 100644 --- a/tools/lib/bpf/features.c +++ b/tools/lib/bpf/features.c @@ -506,6 +506,11 @@ static int probe_kern_arg_ctx_tag(int token_fd) return probe_fd(prog_fd); } =20 +static int probe_bpf_syscall_common_attrs(int token_fd) +{ + return probe_sys_bpf_ext(); +} + typedef int (*feature_probe_fn)(int /* token_fd */); =20 static struct kern_feature_cache feature_cache; @@ -581,6 +586,9 @@ static struct kern_feature_desc { [FEAT_BTF_QMARK_DATASEC] =3D { "BTF DATASEC names starting from '?'", probe_kern_btf_qmark_datasec, }, + [FEAT_BPF_SYSCALL_COMMON_ATTRS] =3D { + "BPF syscall common attributes support", probe_bpf_syscall_common_attrs, + }, }; =20 bool feat_supported(struct kern_feature_cache *cache, enum kern_feature_id= feat_id) diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_interna= l.h index fc59b21b51b5..aa16be869c4f 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -392,6 +392,8 @@ enum kern_feature_id { FEAT_ARG_CTX_TAG, /* Kernel supports '?' at the front of datasec names */ FEAT_BTF_QMARK_DATASEC, + /* Kernel supports BPF syscall common attributes */ + FEAT_BPF_SYSCALL_COMMON_ATTRS, __FEAT_CNT, }; =20 @@ -757,4 +759,5 @@ int probe_fd(int fd); #define SHA256_DWORD_SIZE SHA256_DIGEST_LENGTH / sizeof(__u64) =20 void libbpf_sha256(const void *data, size_t len, __u8 out[SHA256_DIGEST_LE= NGTH]); +int probe_sys_bpf_ext(void); #endif /* __LIBBPF_LIBBPF_INTERNAL_H */ --=20 2.52.0 From nobody Thu Apr 2 09:27:35 2026 Received: from out-181.mta0.migadu.com (out-181.mta0.migadu.com [91.218.175.181]) (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 A20783168F6 for ; Mon, 16 Feb 2026 15:06:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.181 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254402; cv=none; b=NJNxVnOiIfSH2E5RZd7wBjIWjpeDZFGFf/MqEpXxN7aWYVxZ0i4VxCInxvJ55J+shYVfr6AcZQBwFCE9wRNAZw6uV2NBEPHkMrf9WS0OW9fk2WdPYZenzU/hS/eys/c3mx6Tu/+ORqiGHQE9rtzHtElYCTRDZRpqpkIEKwpIDr0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254402; c=relaxed/simple; bh=vIb3WtV6muTrwY74mrd0aD9sE5NcgH/zI69x2P/K4OI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=USGK45OK6AZBeoBxNC1PV13UdAlhQaygMTj2dsgZCfecidVwz3lD9Gl9FBeVtBIVOqBxt/UtprSbvzTYsjjHxjLs4uxgyPtI1EaRBTsh8cz9wtyTm5pj7afwQyQN/bSqiM10MG6h0sZY4y0ZrBsL7niEGzOAE+c+WaXbAIFs3jU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=DqOKndYx; arc=none smtp.client-ip=91.218.175.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="DqOKndYx" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771254397; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=XUYvhzf4IP0hxOuyLi9vHfUxsMp6/UWnkq0DQeM7pl8=; b=DqOKndYxuuHAIuZm4J+AB1uVeyLSWtPOPLELVl5HlWciiMRZKzJ1t2IByXJPvm4UdbWt42 SZ3qBlkfZz+AAx/q69E/IT88xtktLkkkIe/rjpxCIRhyh+h1JUZITAtGbV5Fg0OnBbGmAq HlyCkH7j5JOgK99Goh/CArCA/b4FsSg= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v11 3/8] bpf: Refactor reporting log_true_size for prog_load Date: Mon, 16 Feb 2026 23:04:40 +0800 Message-ID: <20260216150445.68278-4-leon.hwang@linux.dev> In-Reply-To: <20260216150445.68278-1-leon.hwang@linux.dev> References: <20260216150445.68278-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" The next commit will add support for reporting logs via extended common attributes, including 'log_true_size'. To prepare for that, refactor the 'log_true_size' reporting logic by introducing a new struct bpf_log_attr to encapsulate log-related behavior: * bpf_log_attr_init(): initialize log fields, which will support extended common attributes in the next commit. * bpf_log_attr_finalize(): handle log finalization and write back 'log_true_size' to userspace. Acked-by: Andrii Nakryiko Signed-off-by: Leon Hwang --- include/linux/bpf.h | 4 +++- include/linux/bpf_verifier.h | 11 +++++++++++ kernel/bpf/log.c | 25 +++++++++++++++++++++++++ kernel/bpf/syscall.c | 13 ++++++++++--- kernel/bpf/verifier.c | 17 ++++------------- 5 files changed, 53 insertions(+), 17 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index cd9b96434904..d4dbcc7ad156 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -2913,7 +2913,9 @@ int bpf_check_uarg_tail_zero(bpfptr_t uaddr, size_t e= xpected_size, size_t actual_size); =20 /* verify correctness of eBPF program */ -int bpf_check(struct bpf_prog **fp, union bpf_attr *attr, bpfptr_t uattr, = u32 uattr_size); +struct bpf_log_attr; +int bpf_check(struct bpf_prog **fp, union bpf_attr *attr, bpfptr_t uattr, + struct bpf_log_attr *attr_log); =20 #ifndef CONFIG_BPF_JIT_ALWAYS_ON void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth); diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index c1e30096ea7b..b21cb7066f6f 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -634,6 +634,17 @@ static inline bool bpf_verifier_log_needed(const struc= t bpf_verifier_log *log) return log && log->level; } =20 +struct bpf_log_attr { + char __user *log_buf; + u32 log_size; + u32 log_level; + u32 __user *log_true_size; +}; + +int bpf_log_attr_init(struct bpf_log_attr *log, u64 log_buf, u32 log_size,= u32 log_level, + u32 __user *log_true_size); +int bpf_log_attr_finalize(struct bpf_log_attr *attr, struct bpf_verifier_l= og *log); + #define BPF_MAX_SUBPROGS 256 =20 struct bpf_subprog_arg_info { diff --git a/kernel/bpf/log.c b/kernel/bpf/log.c index 37d72b052192..d4dbf2465620 100644 --- a/kernel/bpf/log.c +++ b/kernel/bpf/log.c @@ -865,3 +865,28 @@ void print_insn_state(struct bpf_verifier_env *env, co= nst struct bpf_verifier_st } print_verifier_state(env, vstate, frameno, false); } + +int bpf_log_attr_init(struct bpf_log_attr *log, u64 log_buf, u32 log_size,= u32 log_level, + u32 __user *log_true_size) +{ + memset(log, 0, sizeof(*log)); + log->log_buf =3D u64_to_user_ptr(log_buf); + log->log_size =3D log_size; + log->log_level =3D log_level; + log->log_true_size =3D log_true_size; + return 0; +} + +int bpf_log_attr_finalize(struct bpf_log_attr *attr, struct bpf_verifier_l= og *log) +{ + u32 log_true_size; + int err; + + err =3D bpf_vlog_finalize(log, &log_true_size); + + if (attr->log_true_size && copy_to_user(attr->log_true_size, &log_true_si= ze, + sizeof(log_true_size))) + return -EFAULT; + + return err; +} diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index e7ab87908189..d6fa752401a9 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2868,7 +2868,7 @@ static int bpf_prog_mark_insn_arrays_ready(struct bpf= _prog *prog) /* last field in 'union bpf_attr' used by this command */ #define BPF_PROG_LOAD_LAST_FIELD keyring_id =20 -static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_s= ize) +static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_= log_attr *attr_log) { enum bpf_prog_type type =3D attr->prog_type; struct bpf_prog *prog, *dst_prog =3D NULL; @@ -3086,7 +3086,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr= _t uattr, u32 uattr_size) goto free_prog_sec; =20 /* run eBPF verifier */ - err =3D bpf_check(&prog, attr, uattr, uattr_size); + err =3D bpf_check(&prog, attr, uattr, attr_log); if (err < 0) goto free_used_maps; =20 @@ -6190,7 +6190,10 @@ static int prog_assoc_struct_ops(union bpf_attr *att= r) static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size, bpfptr_t uattr_common, unsigned int size_common) { + bool from_user =3D !bpfptr_is_kernel(uattr); struct bpf_common_attr attr_common; + u32 __user *log_true_size =3D NULL; + struct bpf_log_attr attr_log; union bpf_attr attr; int err; =20 @@ -6242,7 +6245,11 @@ static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uatt= r, unsigned int size, err =3D map_freeze(&attr); break; case BPF_PROG_LOAD: - err =3D bpf_prog_load(&attr, uattr, size); + if (from_user && size >=3D offsetofend(union bpf_attr, log_true_size)) + log_true_size =3D uattr.user + offsetof(union bpf_attr, log_true_size); + err =3D bpf_log_attr_init(&attr_log, attr.log_buf, attr.log_size, attr.l= og_level, + log_true_size); + err =3D err ?: bpf_prog_load(&attr, uattr, &attr_log); break; case BPF_OBJ_PIN: err =3D bpf_obj_pin(&attr); diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 0162f946032f..779cf863dc9a 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -25790,12 +25790,12 @@ static int compute_scc(struct bpf_verifier_env *e= nv) return err; } =20 -int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr= , __u32 uattr_size) +int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, + struct bpf_log_attr *attr_log) { u64 start_time =3D ktime_get_ns(); struct bpf_verifier_env *env; int i, len, ret =3D -EINVAL, err; - u32 log_true_size; bool is_priv; =20 BTF_TYPE_EMIT(enum bpf_features); @@ -25842,9 +25842,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_att= r *attr, bpfptr_t uattr, __u3 /* user could have requested verbose verifier output * and supplied buffer to store the verification trace */ - ret =3D bpf_vlog_init(&env->log, attr->log_level, - (char __user *) (unsigned long) attr->log_buf, - attr->log_size); + ret =3D bpf_vlog_init(&env->log, attr_log->log_level, attr_log->log_buf, = attr_log->log_size); if (ret) goto err_unlock; =20 @@ -25994,17 +25992,10 @@ int bpf_check(struct bpf_prog **prog, union bpf_a= ttr *attr, bpfptr_t uattr, __u3 env->prog->aux->verified_insns =3D env->insn_processed; =20 /* preserve original error even if log finalization is successful */ - err =3D bpf_vlog_finalize(&env->log, &log_true_size); + err =3D bpf_log_attr_finalize(attr_log, &env->log); if (err) ret =3D err; =20 - if (uattr_size >=3D offsetofend(union bpf_attr, log_true_size) && - copy_to_bpfptr_offset(uattr, offsetof(union bpf_attr, log_true_size), - &log_true_size, sizeof(log_true_size))) { - ret =3D -EFAULT; - goto err_release_maps; - } - if (ret) goto err_release_maps; =20 --=20 2.52.0 From nobody Thu Apr 2 09:27:35 2026 Received: from out-183.mta0.migadu.com (out-183.mta0.migadu.com [91.218.175.183]) (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 E19D33128C6 for ; 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DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771254410; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pd+XEM/uBOYtPAyprTQvce3wuyLfg25eqbS4ipXXqUk=; b=J1d+XsmRKtjzVV3oHSDUSa7AXBQL59q29LPMio73TKo9avVP5ZqOU+ZYAasmRGs63+5lHi c4mARZXmrQ9JjuOCiP+113qc0JFUIxHBRp9gZKvMoF+SAAFjQzOoxYEPc7Vga6Avfz6IJZ 3uxzKBII4ODX0taSnC8aLuWSg9ZtY2c= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v11 4/8] bpf: Add syscall common attributes support for prog_load Date: Mon, 16 Feb 2026 23:04:41 +0800 Message-ID: <20260216150445.68278-5-leon.hwang@linux.dev> In-Reply-To: <20260216150445.68278-1-leon.hwang@linux.dev> References: <20260216150445.68278-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" BPF_PROG_LOAD can now take log parameters from both union bpf_attr and struct bpf_common_attr. The merge rules are: - if both sides provide a complete log tuple (buf/size/level) and they match, use it; - if only one side provides log parameters, use that one; - if both sides provide complete tuples but they differ, return -EINVAL. Signed-off-by: Leon Hwang --- include/linux/bpf_verifier.h | 3 ++- kernel/bpf/log.c | 38 ++++++++++++++++++++++++++++-------- kernel/bpf/syscall.c | 2 +- 3 files changed, 33 insertions(+), 10 deletions(-) diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index b21cb7066f6f..de1d42a48af5 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -642,7 +642,8 @@ struct bpf_log_attr { }; =20 int bpf_log_attr_init(struct bpf_log_attr *log, u64 log_buf, u32 log_size,= u32 log_level, - u32 __user *log_true_size); + u32 __user *log_true_size, struct bpf_common_attr *common, bpfptr_= t uattr, + u32 size); int bpf_log_attr_finalize(struct bpf_log_attr *attr, struct bpf_verifier_l= og *log); =20 #define BPF_MAX_SUBPROGS 256 diff --git a/kernel/bpf/log.c b/kernel/bpf/log.c index d4dbf2465620..a1c0c42b0b8c 100644 --- a/kernel/bpf/log.c +++ b/kernel/bpf/log.c @@ -13,17 +13,17 @@ =20 #define verbose(env, fmt, args...) bpf_verifier_log_write(env, fmt, ##args) =20 -static bool bpf_verifier_log_attr_valid(const struct bpf_verifier_log *log) +static bool bpf_verifier_log_attr_valid(u32 log_level, char __user *log_bu= f, u32 log_size) { /* ubuf and len_total should both be specified (or not) together */ - if (!!log->ubuf !=3D !!log->len_total) + if (!!log_buf !=3D !!log_size) return false; /* log buf without log_level is meaningless */ - if (log->ubuf && log->level =3D=3D 0) + if (log_buf && log_level =3D=3D 0) return false; - if (log->level & ~BPF_LOG_MASK) + if (log_level & ~BPF_LOG_MASK) return false; - if (log->len_total > UINT_MAX >> 2) + if (log_size > UINT_MAX >> 2) return false; return true; } @@ -36,7 +36,7 @@ int bpf_vlog_init(struct bpf_verifier_log *log, u32 log_l= evel, log->len_total =3D log_size; =20 /* log attributes have to be sane */ - if (!bpf_verifier_log_attr_valid(log)) + if (!bpf_verifier_log_attr_valid(log_level, log_buf, log_size)) return -EINVAL; =20 return 0; @@ -867,13 +867,35 @@ void print_insn_state(struct bpf_verifier_env *env, c= onst struct bpf_verifier_st } =20 int bpf_log_attr_init(struct bpf_log_attr *log, u64 log_buf, u32 log_size,= u32 log_level, - u32 __user *log_true_size) + u32 __user *log_true_size, struct bpf_common_attr *common, bpfptr_= t uattr, + u32 size) { + char __user *ubuf_common =3D u64_to_user_ptr(common->log_buf); + char __user *ubuf =3D u64_to_user_ptr(log_buf); + + if (!bpf_verifier_log_attr_valid(common->log_level, ubuf_common, common->= log_size) || + !bpf_verifier_log_attr_valid(log_level, ubuf, log_size)) + return -EINVAL; + + if (ubuf && ubuf_common && (ubuf !=3D ubuf_common || log_size !=3D common= ->log_size || + log_level !=3D common->log_level)) + return -EINVAL; + memset(log, 0, sizeof(*log)); - log->log_buf =3D u64_to_user_ptr(log_buf); + log->log_buf =3D ubuf; log->log_size =3D log_size; log->log_level =3D log_level; log->log_true_size =3D log_true_size; + + if (!ubuf && ubuf_common) { + log->log_buf =3D ubuf_common; + log->log_size =3D common->log_size; + log->log_level =3D common->log_level; + log->log_true_size =3D NULL; + if (size >=3D offsetofend(struct bpf_common_attr, log_true_size)) + log->log_true_size =3D uattr.user + + offsetof(struct bpf_common_attr, log_true_size); + } return 0; } =20 diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index d6fa752401a9..f37396f71e8d 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -6248,7 +6248,7 @@ static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr= , unsigned int size, if (from_user && size >=3D offsetofend(union bpf_attr, log_true_size)) log_true_size =3D uattr.user + offsetof(union bpf_attr, log_true_size); err =3D bpf_log_attr_init(&attr_log, attr.log_buf, attr.log_size, attr.l= og_level, - log_true_size); + log_true_size, &attr_common, uattr_common, size_common); err =3D err ?: bpf_prog_load(&attr, uattr, &attr_log); break; case BPF_OBJ_PIN: --=20 2.52.0 From nobody Thu Apr 2 09:27:35 2026 Received: from out-173.mta0.migadu.com (out-173.mta0.migadu.com [91.218.175.173]) (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 42C9830CD91 for ; Mon, 16 Feb 2026 15:07:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254426; cv=none; b=dwXSdL/w7cXQ1YnlZGi3BavlVsfo/QoZL4vttga2RqC7xPpNroQUhQkPYMMDtmF0UO9ZXs524z1FQJ6XCPLhq8Rd0sF/BCTtbzi6bk8bc/k8OXmHPhfCFqLLzJLTPa0pW92qL25NoO0hkm6VMkUkMFBWC+yT5h04eFeEOIfmaew= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; 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DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771254422; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=rNTHfnyugYeRFm01S4dbRPUG/ER5O10oix5d8Wl3AjQ=; b=K6/Xgof5k/SOw/XQ5xwKOrq6Ddj4F1H0K78kRvpCuMrqOmfOLI2SlwV76xEycRWfUl0tQ7 H2bxLIsiWdRm1YNACmEOHfz/IRTVbavU3Q/n5poLYPY2dmS5iLnvcyHg9SLx6P2ceZ2HGA iB8cBDVRTuEtEod4hpnwV2Q8U4Aja3Y= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v11 5/8] bpf: Add syscall common attributes support for btf_load Date: Mon, 16 Feb 2026 23:04:42 +0800 Message-ID: <20260216150445.68278-6-leon.hwang@linux.dev> In-Reply-To: <20260216150445.68278-1-leon.hwang@linux.dev> References: <20260216150445.68278-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" BPF_BTF_LOAD can now take log parameters from both union bpf_attr and struct bpf_common_attr, with the same merge rules as BPF_PROG_LOAD: - if both sides provide a complete log tuple (buf/size/level) and they match, use it; - if only one side provides log parameters, use that one; - if both sides provide complete tuples but they differ, return -EINVAL. Acked-by: Andrii Nakryiko Signed-off-by: Leon Hwang --- include/linux/btf.h | 3 ++- kernel/bpf/btf.c | 30 +++++++----------------------- kernel/bpf/syscall.c | 11 ++++++++--- 3 files changed, 17 insertions(+), 27 deletions(-) diff --git a/include/linux/btf.h b/include/linux/btf.h index 48108471c5b1..f64d87315c5f 100644 --- a/include/linux/btf.h +++ b/include/linux/btf.h @@ -145,7 +145,8 @@ const char *btf_get_name(const struct btf *btf); void btf_get(struct btf *btf); void btf_put(struct btf *btf); const struct btf_header *btf_header(const struct btf *btf); -int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr, u32 uattr_sz); +struct bpf_log_attr; +int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_= attr *attr_log); struct btf *btf_get_by_fd(int fd); int btf_get_info_by_fd(const struct btf *btf, const union bpf_attr *attr, diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 7708958e3fb8..810007028b72 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -5857,25 +5857,10 @@ static int btf_check_type_tags(struct btf_verifier_= env *env, return 0; } =20 -static int finalize_log(struct bpf_verifier_log *log, bpfptr_t uattr, u32 = uattr_size) -{ - u32 log_true_size; - int err; - - err =3D bpf_vlog_finalize(log, &log_true_size); - - if (uattr_size >=3D offsetofend(union bpf_attr, btf_log_true_size) && - copy_to_bpfptr_offset(uattr, offsetof(union bpf_attr, btf_log_true_si= ze), - &log_true_size, sizeof(log_true_size))) - err =3D -EFAULT; - - return err; -} - -static struct btf *btf_parse(const union bpf_attr *attr, bpfptr_t uattr, u= 32 uattr_size) +static struct btf *btf_parse(const union bpf_attr *attr, bpfptr_t uattr, + struct bpf_log_attr *attr_log) { bpfptr_t btf_data =3D make_bpfptr(attr->btf, uattr.is_kernel); - char __user *log_ubuf =3D u64_to_user_ptr(attr->btf_log_buf); struct btf_struct_metas *struct_meta_tab; struct btf_verifier_env *env =3D NULL; struct btf *btf =3D NULL; @@ -5892,8 +5877,7 @@ static struct btf *btf_parse(const union bpf_attr *at= tr, bpfptr_t uattr, u32 uat /* user could have requested verbose verifier output * and supplied buffer to store the verification trace */ - err =3D bpf_vlog_init(&env->log, attr->btf_log_level, - log_ubuf, attr->btf_log_size); + err =3D bpf_vlog_init(&env->log, attr_log->log_level, attr_log->log_buf, = attr_log->log_size); if (err) goto errout_free; =20 @@ -5954,7 +5938,7 @@ static struct btf *btf_parse(const union bpf_attr *at= tr, bpfptr_t uattr, u32 uat } } =20 - err =3D finalize_log(&env->log, uattr, uattr_size); + err =3D bpf_log_attr_finalize(attr_log, &env->log); if (err) goto errout_free; =20 @@ -5966,7 +5950,7 @@ static struct btf *btf_parse(const union bpf_attr *at= tr, bpfptr_t uattr, u32 uat btf_free_struct_meta_tab(btf); errout: /* overwrite err with -ENOSPC or -EFAULT */ - ret =3D finalize_log(&env->log, uattr, uattr_size); + ret =3D bpf_log_attr_finalize(attr_log, &env->log); if (ret) err =3D ret; errout_free: @@ -8137,12 +8121,12 @@ static int __btf_new_fd(struct btf *btf) return anon_inode_getfd("btf", &btf_fops, btf, O_RDONLY | O_CLOEXEC); } =20 -int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) +int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_= attr *attr_log) { struct btf *btf; int ret; =20 - btf =3D btf_parse(attr, uattr, uattr_size); + btf =3D btf_parse(attr, uattr, attr_log); if (IS_ERR(btf)) return PTR_ERR(btf); =20 diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index f37396f71e8d..be66b824e4cf 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -5449,7 +5449,7 @@ static int bpf_obj_get_info_by_fd(const union bpf_att= r *attr, =20 #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd =20 -static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 = uattr_size) +static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, struct= bpf_log_attr *attr_log) { struct bpf_token *token =3D NULL; =20 @@ -5476,7 +5476,7 @@ static int bpf_btf_load(const union bpf_attr *attr, b= pfptr_t uattr, __u32 uattr_ =20 bpf_token_put(token); =20 - return btf_new_fd(attr, uattr, uattr_size); + return btf_new_fd(attr, uattr, attr_log); } =20 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD fd_by_id_token_fd @@ -6294,7 +6294,12 @@ static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uatt= r, unsigned int size, err =3D bpf_raw_tracepoint_open(&attr); break; case BPF_BTF_LOAD: - err =3D bpf_btf_load(&attr, uattr, size); + if (from_user && size >=3D offsetofend(union bpf_attr, btf_log_true_size= )) + log_true_size =3D uattr.user + offsetof(union bpf_attr, btf_log_true_si= ze); + err =3D bpf_log_attr_init(&attr_log, attr.btf_log_buf, attr.btf_log_size, + attr.btf_log_level, log_true_size, &attr_common, + uattr_common, size_common); + err =3D err ?: bpf_btf_load(&attr, uattr, &attr_log); break; case BPF_BTF_GET_FD_BY_ID: err =3D bpf_btf_get_fd_by_id(&attr); --=20 2.52.0 From nobody Thu Apr 2 09:27:35 2026 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (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 490D8314D1D for ; Mon, 16 Feb 2026 15:07:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.185 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; 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DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771254448; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SFGJ50n9+bv2f9D9DqaYiurpxwP/FhFm6n1QOwE8JOk=; b=pbXaEZxATZcpgwgRYW4SRhxr1Mzax45Gr4RpKnagXm1u9Iv6ww4EeD1GEfEDK/ujR3CYYn fDWled8rRW4PYvlXWGT/GayC0VUs1TgKAsGdh2Pma92m19fktf8Fd/U8XNxzmijuiWxIiE gQ1LnJ5nZy1fmD3AQC3Lle5XVKyQCjQ= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v11 6/8] bpf: Add syscall common attributes support for map_create Date: Mon, 16 Feb 2026 23:04:43 +0800 Message-ID: <20260216150445.68278-7-leon.hwang@linux.dev> In-Reply-To: <20260216150445.68278-1-leon.hwang@linux.dev> References: <20260216150445.68278-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" Many BPF_MAP_CREATE validation failures currently return -EINVAL without any explanation to userspace. Plumb common syscall log attributes into map_create(), create a verifier log from bpf_common_attr::log_buf/log_size/log_level, and report map-creation failure reasons through that buffer. This improves debuggability by allowing userspace to inspect why map creation failed and read back log_true_size from common attributes. Signed-off-by: Leon Hwang --- include/linux/bpf_verifier.h | 3 ++ kernel/bpf/log.c | 30 +++++++++++++++++ kernel/bpf/syscall.c | 65 ++++++++++++++++++++++++++++++------ 3 files changed, 88 insertions(+), 10 deletions(-) diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index de1d42a48af5..6e02081fa24b 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -644,6 +644,9 @@ struct bpf_log_attr { int bpf_log_attr_init(struct bpf_log_attr *log, u64 log_buf, u32 log_size,= u32 log_level, u32 __user *log_true_size, struct bpf_common_attr *common, bpfptr_= t uattr, u32 size); +struct bpf_verifier_log *bpf_log_attr_create_vlog(struct bpf_log_attr *att= r_log, + struct bpf_common_attr *common, bpfptr_t uattr, + u32 size); int bpf_log_attr_finalize(struct bpf_log_attr *attr, struct bpf_verifier_l= og *log); =20 #define BPF_MAX_SUBPROGS 256 diff --git a/kernel/bpf/log.c b/kernel/bpf/log.c index a1c0c42b0b8c..c31d4cf17517 100644 --- a/kernel/bpf/log.c +++ b/kernel/bpf/log.c @@ -899,6 +899,36 @@ int bpf_log_attr_init(struct bpf_log_attr *log, u64 lo= g_buf, u32 log_size, u32 l return 0; } =20 + +struct bpf_verifier_log *bpf_log_attr_create_vlog(struct bpf_log_attr *att= r_log, + struct bpf_common_attr *common, bpfptr_t uattr, + u32 size) +{ + struct bpf_verifier_log *log; + int err; + + memset(attr_log, 0, sizeof(*attr_log)); + if (size >=3D offsetofend(struct bpf_common_attr, log_true_size)) + attr_log->log_true_size =3D uattr.user + offsetof(struct bpf_common_attr, + log_true_size); + + if (!common->log_buf) + return NULL; + + log =3D kzalloc_obj(*log, GFP_KERNEL); + if (!log) + return ERR_PTR(-ENOMEM); + + err =3D bpf_vlog_init(log, common->log_level, u64_to_user_ptr(common->log= _buf), + common->log_size); + if (err) { + kfree(log); + return ERR_PTR(err); + } + + return log; +} + int bpf_log_attr_finalize(struct bpf_log_attr *attr, struct bpf_verifier_l= og *log) { u32 log_true_size; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index be66b824e4cf..6f89dbbceb64 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1366,7 +1366,7 @@ static int map_check_btf(struct bpf_map *map, struct = bpf_token *token, =20 #define BPF_MAP_CREATE_LAST_FIELD excl_prog_hash_size /* called via syscall */ -static int map_create(union bpf_attr *attr, bpfptr_t uattr) +static int __map_create(union bpf_attr *attr, bpfptr_t uattr, struct bpf_v= erifier_log *log) { const struct bpf_map_ops *ops; struct bpf_token *token =3D NULL; @@ -1378,8 +1378,10 @@ static int map_create(union bpf_attr *attr, bpfptr_t= uattr) int err; =20 err =3D CHECK_ATTR(BPF_MAP_CREATE); - if (err) + if (err) { + bpf_log(log, "Invalid attr.\n"); return -EINVAL; + } =20 /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it * to avoid per-map type checks tripping on unknown flag @@ -1388,17 +1390,25 @@ static int map_create(union bpf_attr *attr, bpfptr_= t uattr) attr->map_flags &=3D ~BPF_F_TOKEN_FD; =20 if (attr->btf_vmlinux_value_type_id) { - if (attr->map_type !=3D BPF_MAP_TYPE_STRUCT_OPS || - attr->btf_key_type_id || attr->btf_value_type_id) + if (attr->map_type !=3D BPF_MAP_TYPE_STRUCT_OPS) { + bpf_log(log, "btf_vmlinux_value_type_id can only be used with struct_op= s maps.\n"); return -EINVAL; + } + if (attr->btf_key_type_id || attr->btf_value_type_id) { + bpf_log(log, "btf_vmlinux_value_type_id is mutually exclusive with btf_= key_type_id and btf_value_type_id.\n"); + return -EINVAL; + } } else if (attr->btf_key_type_id && !attr->btf_value_type_id) { + bpf_log(log, "Invalid btf_value_type_id.\n"); return -EINVAL; } =20 if (attr->map_type !=3D BPF_MAP_TYPE_BLOOM_FILTER && attr->map_type !=3D BPF_MAP_TYPE_ARENA && - attr->map_extra !=3D 0) + attr->map_extra !=3D 0) { + bpf_log(log, "Invalid map_extra.\n"); return -EINVAL; + } =20 f_flags =3D bpf_get_file_flag(attr->map_flags); if (f_flags < 0) @@ -1406,13 +1416,17 @@ static int map_create(union bpf_attr *attr, bpfptr_= t uattr) =20 if (numa_node !=3D NUMA_NO_NODE && ((unsigned int)numa_node >=3D nr_node_ids || - !node_online(numa_node))) + !node_online(numa_node))) { + bpf_log(log, "Invalid numa_node.\n"); return -EINVAL; + } =20 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ map_type =3D attr->map_type; - if (map_type >=3D ARRAY_SIZE(bpf_map_types)) + if (map_type >=3D ARRAY_SIZE(bpf_map_types)) { + bpf_log(log, "Invalid map_type.\n"); return -EINVAL; + } map_type =3D array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types)); ops =3D bpf_map_types[map_type]; if (!ops) @@ -1430,8 +1444,10 @@ static int map_create(union bpf_attr *attr, bpfptr_t= uattr) =20 if (token_flag) { token =3D bpf_token_get_from_fd(attr->map_token_fd); - if (IS_ERR(token)) + if (IS_ERR(token)) { + bpf_log(log, "Invalid map_token_fd.\n"); return PTR_ERR(token); + } =20 /* if current token doesn't grant map creation permissions, * then we can't use this token, so ignore it and rely on @@ -1514,8 +1530,10 @@ static int map_create(union bpf_attr *attr, bpfptr_t= uattr) =20 err =3D bpf_obj_name_cpy(map->name, attr->map_name, sizeof(attr->map_name)); - if (err < 0) + if (err < 0) { + bpf_log(log, "Invalid map_name.\n"); goto free_map; + } =20 preempt_disable(); map->cookie =3D gen_cookie_next(&bpf_map_cookie); @@ -1538,6 +1556,7 @@ static int map_create(union bpf_attr *attr, bpfptr_t = uattr) =20 btf =3D btf_get_by_fd(attr->btf_fd); if (IS_ERR(btf)) { + bpf_log(log, "Invalid btf_fd.\n"); err =3D PTR_ERR(btf); goto free_map; } @@ -1565,6 +1584,7 @@ static int map_create(union bpf_attr *attr, bpfptr_t = uattr) bpfptr_t uprog_hash =3D make_bpfptr(attr->excl_prog_hash, uattr.is_kerne= l); =20 if (attr->excl_prog_hash_size !=3D SHA256_DIGEST_SIZE) { + bpf_log(log, "Invalid excl_prog_hash_size.\n"); err =3D -EINVAL; goto free_map; } @@ -1580,6 +1600,7 @@ static int map_create(union bpf_attr *attr, bpfptr_t = uattr) goto free_map; } } else if (attr->excl_prog_hash_size) { + bpf_log(log, "Invalid excl_prog_hash_size.\n"); err =3D -EINVAL; goto free_map; } @@ -1618,6 +1639,30 @@ static int map_create(union bpf_attr *attr, bpfptr_t= uattr) return err; } =20 +static int map_create(union bpf_attr *attr, bpfptr_t uattr, struct bpf_com= mon_attr *attr_common, + bpfptr_t uattr_common, u32 size_common) +{ + struct bpf_verifier_log *log; + struct bpf_log_attr attr_log; + int err, ret; + + log =3D bpf_log_attr_create_vlog(&attr_log, attr_common, uattr_common, si= ze_common); + if (IS_ERR(log)) + return PTR_ERR(log); + + err =3D __map_create(attr, uattr, log); + if (err >=3D 0) + goto free; + + ret =3D bpf_log_attr_finalize(&attr_log, log); + if (ret) + err =3D ret; + +free: + kfree(log); + return err; +} + void bpf_map_inc(struct bpf_map *map) { atomic64_inc(&map->refcnt); @@ -6227,7 +6272,7 @@ static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr= , unsigned int size, =20 switch (cmd) { case BPF_MAP_CREATE: - err =3D map_create(&attr, uattr); + err =3D map_create(&attr, uattr, &attr_common, uattr_common, size_common= ); break; case BPF_MAP_LOOKUP_ELEM: err =3D map_lookup_elem(&attr); --=20 2.52.0 From nobody Thu Apr 2 09:27:35 2026 Received: from out-172.mta0.migadu.com (out-172.mta0.migadu.com [91.218.175.172]) (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 2F42631196F for ; Mon, 16 Feb 2026 15:07:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254465; cv=none; b=DC32Tc7lwsXvr6OKe3Ce6+IiRoRdhAAChqpAR9hNI3q51GSmZULiM2LYSrKuk5IsuF0SoWed7xwQy5HLi3kd1vSdW6ytx6UeNdeUUFb+fOLZKJ8BH3EQwvemKzE0sxjh+QSjc6DADR0oVt0luRPFaHIxNSjCk5jyR8Y8QG0aXdM= ARC-Message-Signature: i=1; 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DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771254461; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WEd1Tu6pzCQjp2hnQoKiK4JRxMafdGLudagS7tdkGr4=; b=I5pFXRmLHcRV3WQIWWPVikxPMT/hlh3q02/8GP4z3bQvFfnTC+lEs8o7NmmXGCjn2XLcG4 vDvF6zxrE1AMhWlVkG03GWAIUMfL8bX+PDq8pmQTixu7L6Ea2wiKjNIxX/WgJVPSTquN1Y tciiQx9KMGXWQ4nZuuWqJNOdYMvkAIY= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v11 7/8] libbpf: Add syscall common attributes support for map_create Date: Mon, 16 Feb 2026 23:04:44 +0800 Message-ID: <20260216150445.68278-8-leon.hwang@linux.dev> In-Reply-To: <20260216150445.68278-1-leon.hwang@linux.dev> References: <20260216150445.68278-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" With the previous commit adding common attribute support for BPF_MAP_CREATE, users can now retrieve detailed error messages when map creation fails via the log_buf field. Introduce struct bpf_log_opts with the following fields: log_buf, log_size, log_level, and log_true_size. Extend bpf_map_create_opts with a new field log_opts, allowing users to capture and inspect log messages on map creation failures. Acked-by: Andrii Nakryiko Signed-off-by: Leon Hwang --- tools/lib/bpf/bpf.c | 16 +++++++++++++++- tools/lib/bpf/bpf.h | 17 ++++++++++++++++- 2 files changed, 31 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 9d8740761b7a..0c3e40844d80 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -209,6 +209,9 @@ int bpf_map_create(enum bpf_map_type map_type, const struct bpf_map_create_opts *opts) { const size_t attr_sz =3D offsetofend(union bpf_attr, excl_prog_hash_size); + const size_t attr_common_sz =3D sizeof(struct bpf_common_attr); + struct bpf_common_attr attr_common; + struct bpf_log_opts *log_opts; union bpf_attr attr; int fd; =20 @@ -242,7 +245,18 @@ int bpf_map_create(enum bpf_map_type map_type, attr.excl_prog_hash =3D ptr_to_u64(OPTS_GET(opts, excl_prog_hash, NULL)); attr.excl_prog_hash_size =3D OPTS_GET(opts, excl_prog_hash_size, 0); =20 - fd =3D sys_bpf_fd(BPF_MAP_CREATE, &attr, attr_sz); + log_opts =3D OPTS_GET(opts, log_opts, NULL); + if (log_opts && feat_supported(NULL, FEAT_BPF_SYSCALL_COMMON_ATTRS)) { + memset(&attr_common, 0, attr_common_sz); + attr_common.log_buf =3D ptr_to_u64(OPTS_GET(log_opts, log_buf, NULL)); + attr_common.log_size =3D OPTS_GET(log_opts, log_size, 0); + attr_common.log_level =3D OPTS_GET(log_opts, log_level, 0); + fd =3D sys_bpf_ext_fd(BPF_MAP_CREATE, &attr, attr_sz, &attr_common, attr= _common_sz); + OPTS_SET(log_opts, log_true_size, attr_common.log_true_size); + } else { + fd =3D sys_bpf_fd(BPF_MAP_CREATE, &attr, attr_sz); + OPTS_SET(log_opts, log_true_size, 0); + } return libbpf_err_errno(fd); } =20 diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 2c8e88ddb674..db834f09799e 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -37,6 +37,18 @@ extern "C" { =20 LIBBPF_API int libbpf_set_memlock_rlim(size_t memlock_bytes); =20 +struct bpf_log_opts { + size_t sz; /* size of this struct for forward/backward compatibility */ + + char *log_buf; + __u32 log_size; + __u32 log_level; + __u32 log_true_size; /* out parameter set by kernel */ + + size_t :0; +}; +#define bpf_log_opts__last_field log_true_size + struct bpf_map_create_opts { size_t sz; /* size of this struct for forward/backward compatibility */ =20 @@ -57,9 +69,12 @@ struct bpf_map_create_opts { =20 const void *excl_prog_hash; __u32 excl_prog_hash_size; + + struct bpf_log_opts *log_opts; + size_t :0; }; -#define bpf_map_create_opts__last_field excl_prog_hash_size +#define bpf_map_create_opts__last_field log_opts =20 LIBBPF_API int bpf_map_create(enum bpf_map_type map_type, const char *map_name, --=20 2.52.0 From nobody Thu Apr 2 09:27:35 2026 Received: from out-189.mta0.migadu.com (out-189.mta0.migadu.com [91.218.175.189]) (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 E5536314A9B for ; Mon, 16 Feb 2026 15:07:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.189 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254477; cv=none; b=Ky4oaaD6D8LsNlGk5eSwyi8asLQO/vEpZrPcOVYRUzEDURtHFcrCzNhnktV5r7vY/KYF5yLSxjAwHtc4k/7VfylGBIAlAHOeF8Ulr+HrRyQHMpppxAjEGTIKxBvoyXwDGI0/XXLvCMlLLClEEsO9fWEszkvfABxfRYe8rXL/ONU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771254477; c=relaxed/simple; bh=uiv5i7ykoQi/imAFG9w62Cq9HOMQY7H+7kuY4uZNwbM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LB4+SrQqswOkokDQ2MLPwP6RSb9R7JgTSKVsoOlDPZ5cfbwsXEjiaA4swet2NGJiNAJ+tTlfQiEWG1w8mBH4U/Gk5VqVuUwWOdNXd2HjTmibORPoZTKoMkSiDrSkCtq2eHldunMJmigfzM4d2hjtO76lQUX0yevxFJHJL1y2ADc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=F0a0OEHk; arc=none smtp.client-ip=91.218.175.189 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="F0a0OEHk" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1771254473; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jNmy8vEFRMQsXmFtGr71cdHXYHhxyH31MwOTXPEe7yY=; b=F0a0OEHkfNgvUS/bOOvV3M9UAgAiw874fESc3CZEqigI1EUzeLJmAOy3fza4UZgZwDPS9E qzZYlPrnzJTaUCxQg+Nbjoo8SUsqDmrBQzI2WEjVVIsBaDMNvcyYGOBPyYN9RdUqFsDZMy xqI+jNDOk5tcihc8Hm5aBGWl+2Lzvpk= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Christian Brauner , Seth Forshee , Yuichiro Tsuji , Andrey Albershteyn , Leon Hwang , Willem de Bruijn , Jason Xing , Tao Chen , Mykyta Yatsenko , Kumar Kartikeya Dwivedi , Anton Protopopov , Amery Hung , Rong Tao , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v11 8/8] selftests/bpf: Add tests to verify map create failure log Date: Mon, 16 Feb 2026 23:04:45 +0800 Message-ID: <20260216150445.68278-9-leon.hwang@linux.dev> In-Reply-To: <20260216150445.68278-1-leon.hwang@linux.dev> References: <20260216150445.68278-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" Add tests to verify that the kernel reports the expected error messages and correct log_true_size when map creation fails. Signed-off-by: Leon Hwang --- .../selftests/bpf/prog_tests/map_init.c | 166 ++++++++++++++++++ 1 file changed, 166 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/map_init.c b/tools/test= ing/selftests/bpf/prog_tests/map_init.c index 14a31109dd0e..b8b727e24b5e 100644 --- a/tools/testing/selftests/bpf/prog_tests/map_init.c +++ b/tools/testing/selftests/bpf/prog_tests/map_init.c @@ -212,3 +212,169 @@ void test_map_init(void) if (test__start_subtest("pcpu_lru_map_init")) test_pcpu_lru_map_init(); } + +static void test_map_create(enum bpf_map_type map_type, const char *map_na= me, + struct bpf_map_create_opts *opts, const char *exp_msg) +{ + const int key_size =3D 4, value_size =3D 4, max_entries =3D 1; + char log_buf[128]; + int fd; + LIBBPF_OPTS(bpf_log_opts, log_opts); + + log_buf[0] =3D '\0'; + log_opts.log_buf =3D log_buf; + log_opts.log_size =3D sizeof(log_buf); + log_opts.log_level =3D 1; + opts->log_opts =3D &log_opts; + fd =3D bpf_map_create(map_type, map_name, key_size, value_size, max_entri= es, opts); + if (!ASSERT_LT(fd, 0, "bpf_map_create")) { + close(fd); + return; + } + + ASSERT_STREQ(log_buf, exp_msg, "log_buf"); + ASSERT_EQ(log_opts.log_true_size, strlen(exp_msg) + 1, "log_true_size"); +} + +static void test_map_create_array(struct bpf_map_create_opts *opts, const = char *exp_msg) +{ + test_map_create(BPF_MAP_TYPE_ARRAY, "test_map_create", opts, exp_msg); +} + +static void test_invalid_vmlinux_value_type_id_struct_ops(void) +{ + const char *msg =3D "btf_vmlinux_value_type_id can only be used with stru= ct_ops maps.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .btf_vmlinux_value_type_id =3D 1, + ); + + test_map_create_array(&opts, msg); +} + +static void test_invalid_vmlinux_value_type_id_kv_type_id(void) +{ + const char *msg =3D "btf_vmlinux_value_type_id is mutually exclusive with= btf_key_type_id and btf_value_type_id.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .btf_vmlinux_value_type_id =3D 1, + .btf_key_type_id =3D 1, + ); + + test_map_create(BPF_MAP_TYPE_STRUCT_OPS, "test_map_create", &opts, msg); +} + +static void test_invalid_value_type_id(void) +{ + const char *msg =3D "Invalid btf_value_type_id.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .btf_key_type_id =3D 1, + ); + + test_map_create_array(&opts, msg); +} + +static void test_invalid_map_extra(void) +{ + const char *msg =3D "Invalid map_extra.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .map_extra =3D 1, + ); + + test_map_create_array(&opts, msg); +} + +static void test_invalid_numa_node(void) +{ + const char *msg =3D "Invalid numa_node.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .map_flags =3D BPF_F_NUMA_NODE, + .numa_node =3D 0xFF, + ); + + test_map_create_array(&opts, msg); +} + +static void test_invalid_map_type(void) +{ + const char *msg =3D "Invalid map_type.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts); + + test_map_create(__MAX_BPF_MAP_TYPE, "test_map_create", &opts, msg); +} + +static void test_invalid_token_fd(void) +{ + const char *msg =3D "Invalid map_token_fd.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .map_flags =3D BPF_F_TOKEN_FD, + .token_fd =3D 0xFF, + ); + + test_map_create_array(&opts, msg); +} + +static void test_invalid_map_name(void) +{ + const char *msg =3D "Invalid map_name.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts); + + test_map_create(BPF_MAP_TYPE_ARRAY, "test-!@#", &opts, msg); +} + +static void test_invalid_btf_fd(void) +{ + const char *msg =3D "Invalid btf_fd.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .btf_fd =3D -1, + .btf_key_type_id =3D 1, + .btf_value_type_id =3D 1, + ); + + test_map_create_array(&opts, msg); +} + +static void test_excl_prog_hash_size_1(void) +{ + const char *msg =3D "Invalid excl_prog_hash_size.\n"; + const char *hash =3D "DEADCODE"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .excl_prog_hash =3D hash, + ); + + test_map_create_array(&opts, msg); +} + +static void test_excl_prog_hash_size_2(void) +{ + const char *msg =3D "Invalid excl_prog_hash_size.\n"; + LIBBPF_OPTS(bpf_map_create_opts, opts, + .excl_prog_hash_size =3D 1, + ); + + test_map_create_array(&opts, msg); +} + +void test_map_create_failure(void) +{ + if (test__start_subtest("invalid_vmlinux_value_type_id_struct_ops")) + test_invalid_vmlinux_value_type_id_struct_ops(); + if (test__start_subtest("invalid_vmlinux_value_type_id_kv_type_id")) + test_invalid_vmlinux_value_type_id_kv_type_id(); + if (test__start_subtest("invalid_value_type_id")) + test_invalid_value_type_id(); + if (test__start_subtest("invalid_map_extra")) + test_invalid_map_extra(); + if (test__start_subtest("invalid_numa_node")) + test_invalid_numa_node(); + if (test__start_subtest("invalid_map_type")) + test_invalid_map_type(); + if (test__start_subtest("invalid_token_fd")) + test_invalid_token_fd(); + if (test__start_subtest("invalid_map_name")) + test_invalid_map_name(); + if (test__start_subtest("invalid_btf_fd")) + test_invalid_btf_fd(); + if (test__start_subtest("invalid_excl_prog_hash_size_1")) + test_excl_prog_hash_size_1(); + if (test__start_subtest("invalid_excl_prog_hash_size_2")) + test_excl_prog_hash_size_2(); +} --=20 2.52.0