diff mbox series

[v2,bpf-next,2/6] selftests/bpf: Implement socket kfuncs for bpf_testmod

Message ID 20240412165230.2009746-3-jrife@google.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series selftests/bpf: Add sockaddr tests for kernel networking | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-2 success Logs for Unittests
bpf/vmtest-bpf-next-VM_Test-1 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-0 success Logs for Lint
bpf/vmtest-bpf-next-VM_Test-3 success Logs for Validate matrix.py
bpf/vmtest-bpf-next-VM_Test-5 success Logs for aarch64-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-4 success Logs for aarch64-gcc / build / build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-10 success Logs for aarch64-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-9 success Logs for aarch64-gcc / test (test_verifier, false, 360) / test_verifier on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-12 success Logs for s390x-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-11 success Logs for s390x-gcc / build / build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-18 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-19 success Logs for x86_64-gcc / build / build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-20 success Logs for x86_64-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-17 success Logs for s390x-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-16 success Logs for s390x-gcc / test (test_verifier, false, 360) / test_verifier on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-26 success Logs for x86_64-gcc / test (test_verifier, false, 360) / test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-28 success Logs for x86_64-llvm-17 / build / build for x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-29 success Logs for x86_64-llvm-17 / build-release / build for x86_64 with llvm-17 and -O2 optimization
bpf/vmtest-bpf-next-VM_Test-33 success Logs for x86_64-llvm-17 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-34 success Logs for x86_64-llvm-17 / veristat
bpf/vmtest-bpf-next-VM_Test-35 success Logs for x86_64-llvm-18 / build / build for x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-36 success Logs for x86_64-llvm-18 / build-release / build for x86_64 with llvm-18 and -O2 optimization
bpf/vmtest-bpf-next-VM_Test-41 success Logs for x86_64-llvm-18 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-42 success Logs for x86_64-llvm-18 / veristat
bpf/vmtest-bpf-next-VM_Test-22 success Logs for x86_64-gcc / test (test_progs, false, 360) / test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-6 success Logs for aarch64-gcc / test (test_maps, false, 360) / test_maps on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-21 success Logs for x86_64-gcc / test (test_maps, false, 360) / test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-23 success Logs for x86_64-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-25 success Logs for x86_64-gcc / test (test_progs_parallel, true, 30) / test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-24 success Logs for x86_64-gcc / test (test_progs_no_alu32_parallel, true, 30) / test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-27 success Logs for x86_64-gcc / veristat / veristat on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-30 success Logs for x86_64-llvm-17 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-31 success Logs for x86_64-llvm-17 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-32 success Logs for x86_64-llvm-17 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-38 success Logs for x86_64-llvm-18 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-37 success Logs for x86_64-llvm-18 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-39 success Logs for x86_64-llvm-18 / test (test_progs_cpuv4, false, 360) / test_progs_cpuv4 on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-40 success Logs for x86_64-llvm-18 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-7 success Logs for aarch64-gcc / test (test_progs, false, 360) / test_progs on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-8 success Logs for aarch64-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-13 success Logs for s390x-gcc / test (test_maps, false, 360) / test_maps on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-14 success Logs for s390x-gcc / test (test_progs, false, 360) / test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-15 success Logs for s390x-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on s390x with gcc
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/build_tools success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 4 maintainers not CCed: linux-stm32@st-md-mailman.stormreply.com linux-arm-kernel@lists.infradead.org alexandre.torgue@foss.st.com mcoquelin.stm32@gmail.com
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch warning CHECK: No space is necessary after a cast
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Jordan Rife April 12, 2024, 4:52 p.m. UTC 
This patch adds a set of kfuncs to bpf_testmod that can be used to
manipulate a socket from kernel space.

Signed-off-by: Jordan Rife <jrife@google.com>
---
 .../selftests/bpf/bpf_testmod/bpf_testmod.c   | 139 ++++++++++++++++++
 .../bpf/bpf_testmod/bpf_testmod_kfunc.h       |  27 ++++
 2 files changed, 166 insertions(+)

Comments

Kui-Feng Lee April 13, 2024, 1:26 a.m. UTC | #1 
On 4/12/24 09:52, Jordan Rife wrote:
> This patch adds a set of kfuncs to bpf_testmod that can be used to
> manipulate a socket from kernel space.
> 
> Signed-off-by: Jordan Rife <jrife@google.com>
> ---
>   .../selftests/bpf/bpf_testmod/bpf_testmod.c   | 139 ++++++++++++++++++
>   .../bpf/bpf_testmod/bpf_testmod_kfunc.h       |  27 ++++
>   2 files changed, 166 insertions(+)
> 
> diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> index 39ad96a18123f..663df8148097e 100644
> --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> @@ -10,18 +10,29 @@
>   #include <linux/percpu-defs.h>
>   #include <linux/sysfs.h>
>   #include <linux/tracepoint.h>
> +#include <linux/net.h>
> +#include <linux/socket.h>
> +#include <linux/nsproxy.h>
> +#include <linux/inet.h>
> +#include <linux/in.h>
> +#include <linux/in6.h>
> +#include <linux/un.h>
> +#include <net/sock.h>
>   #include "bpf_testmod.h"
>   #include "bpf_testmod_kfunc.h"
>   
>   #define CREATE_TRACE_POINTS
>   #include "bpf_testmod-events.h"
>   
> +#define CONNECT_TIMEOUT_SEC 1
> +
>   typedef int (*func_proto_typedef)(long);
>   typedef int (*func_proto_typedef_nested1)(func_proto_typedef);
>   typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1);
>   
>   DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123;
>   long bpf_testmod_test_struct_arg_result;
> +static struct socket *sock;
>   
>   struct bpf_testmod_struct_arg_1 {
>   	int a;
> @@ -494,6 +505,124 @@ __bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused
>   	return arg;
>   }
>   
> +__bpf_kfunc int bpf_kfunc_init_sock(struct init_sock_args *args)
> +{
> +	int proto;
> +
> +	if (sock)
> +		pr_warn("%s called without releasing old sock", __func__);
> +
> +	switch (args->af) {
> +	case AF_INET:
> +	case AF_INET6:
> +		proto = args->type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP;
> +		break;
> +	case AF_UNIX:
> +		proto = PF_UNIX;
> +		break;
> +	default:
> +		pr_err("invalid address family %d\n", args->af);
> +		return -EINVAL;
> +	}
> +
> +	return sock_create_kern(&init_net, args->af, args->type, proto, &sock);
> +}
> +
> +__bpf_kfunc void bpf_kfunc_close_sock(void)
> +{
> +	if (sock) {
> +		sock_release(sock);
> +		sock = NULL;
> +	}
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_connect(struct addr_args *args)
> +{
> +	/* Set timeout for call to kernel_connect() to prevent it from hanging,
> +	 * and consider the connection attempt failed if it returns
> +	 * -EINPROGRESS.
> +	 */
> +	sock->sk->sk_sndtimeo = CONNECT_TIMEOUT_SEC * HZ;
> +
> +	return kernel_connect(sock, (struct sockaddr *)&args->addr,
> +			      args->addrlen, 0);
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_bind(struct addr_args *args)
> +{
> +	return kernel_bind(sock, (struct sockaddr *)&args->addr, args->addrlen);
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_listen(void)
> +{
> +	return kernel_listen(sock, 128);
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args)
> +{
> +	struct msghdr msg = {
> +		.msg_name	= &args->addr.addr,
> +		.msg_namelen	= args->addr.addrlen,
> +	};
> +	struct kvec iov;
> +	int err;
> +
> +	iov.iov_base = args->msg;
> +	iov.iov_len  = args->msglen;

It would be better to check if args->msglen > sizeof(arg->msg) although
this function is just for test cases. Same for args->addr.addrlen.

> +
> +	err = kernel_sendmsg(sock, &msg, &iov, 1, args->msglen);
> +	args->addr.addrlen = msg.msg_namelen;
> +
> +	return err;
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args)
> +{
> +	struct msghdr msg = {
> +		.msg_name	= &args->addr.addr,
> +		.msg_namelen	= args->addr.addrlen,
> +	};
> +	struct kvec iov;
> +	int err;
> +
> +	iov.iov_base = args->msg;
> +	iov.iov_len  = args->msglen;
> +
> +	iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, args->msglen);
> +	err = sock_sendmsg(sock, &msg);
> +	args->addr.addrlen = msg.msg_namelen;
> +
> +	return err;
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_getsockname(struct addr_args *args)
> +{
> +	int err;
> +
> +	err = kernel_getsockname(sock, (struct sockaddr *)&args->addr);
> +	if (err < 0)
> +		goto out;
> +
> +	args->addrlen = err;
> +	err = 0;
> +out:
> +	return err;
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_getpeername(struct addr_args *args)
> +{
> +	int err;
> +
> +	err = kernel_getpeername(sock, (struct sockaddr *)&args->addr);
> +	if (err < 0)
> +		goto out;
> +
> +	args->addrlen = err;
> +	err = 0;
> +out:
> +	return err;
> +}
> +
>   BTF_KFUNCS_START(bpf_testmod_check_kfunc_ids)
>   BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc)
>   BTF_ID_FLAGS(func, bpf_kfunc_call_test1)
> @@ -520,6 +649,15 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS | KF_RCU)
>   BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE)
>   BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg)
>   BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset)
> +BTF_ID_FLAGS(func, bpf_kfunc_init_sock)
> +BTF_ID_FLAGS(func, bpf_kfunc_close_sock)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_connect)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_bind)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_listen)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_sendmsg)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_sock_sendmsg)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getsockname)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getpeername)
>   BTF_KFUNCS_END(bpf_testmod_check_kfunc_ids)
>   
>   static int bpf_testmod_ops_init(struct btf *btf)
> @@ -650,6 +788,7 @@ static int bpf_testmod_init(void)
>   		return ret;
>   	if (bpf_fentry_test1(0) < 0)
>   		return -EINVAL;
> +	sock = NULL;
>   	return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file);
>   }
>   
> diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> index 7c664dd610597..cdf7769a7d8ca 100644
> --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> @@ -64,6 +64,22 @@ struct prog_test_fail3 {
>   	char arr2[];
>   };
>   
> +struct init_sock_args {
> +	int af;
> +	int type;
> +};
> +
> +struct addr_args {
> +	char addr[sizeof(struct __kernel_sockaddr_storage)];
> +	int addrlen;
> +};
> +
> +struct sendmsg_args {
> +	struct addr_args addr;
> +	char msg[10];
> +	int msglen;
> +};
> +
>   struct prog_test_ref_kfunc *
>   bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym;
>   void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
> @@ -106,4 +122,15 @@ void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p);
>   void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len);
>   
>   void bpf_kfunc_common_test(void) __ksym;
> +
> +int bpf_kfunc_init_sock(struct init_sock_args *args) __ksym;
> +void bpf_kfunc_close_sock(void) __ksym;
> +int bpf_kfunc_call_kernel_connect(struct addr_args *args) __ksym;
> +int bpf_kfunc_call_kernel_bind(struct addr_args *args) __ksym;
> +int bpf_kfunc_call_kernel_listen(void) __ksym;
> +int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) __ksym;
> +int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) __ksym;
> +int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) __ksym;
> +int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) __ksym;
> +
>   #endif /* _BPF_TESTMOD_KFUNC_H */
Jordan Rife April 15, 2024, 3:34 p.m. UTC | #2 
> It would be better to check if args->msglen > sizeof(arg->msg) although
> this function is just for test cases. Same for args->addr.addrlen.

Ack. I will add this.

Thanks,
Jordan


On Fri, Apr 12, 2024 at 6:26 PM Kui-Feng Lee <sinquersw@gmail.com> wrote:
>
>
>
> On 4/12/24 09:52, Jordan Rife wrote:
> > This patch adds a set of kfuncs to bpf_testmod that can be used to
> > manipulate a socket from kernel space.
> >
> > Signed-off-by: Jordan Rife <jrife@google.com>
> > ---
> >   .../selftests/bpf/bpf_testmod/bpf_testmod.c   | 139 ++++++++++++++++++
> >   .../bpf/bpf_testmod/bpf_testmod_kfunc.h       |  27 ++++
> >   2 files changed, 166 insertions(+)
> >
> > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > index 39ad96a18123f..663df8148097e 100644
> > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > @@ -10,18 +10,29 @@
> >   #include <linux/percpu-defs.h>
> >   #include <linux/sysfs.h>
> >   #include <linux/tracepoint.h>
> > +#include <linux/net.h>
> > +#include <linux/socket.h>
> > +#include <linux/nsproxy.h>
> > +#include <linux/inet.h>
> > +#include <linux/in.h>
> > +#include <linux/in6.h>
> > +#include <linux/un.h>
> > +#include <net/sock.h>
> >   #include "bpf_testmod.h"
> >   #include "bpf_testmod_kfunc.h"
> >
> >   #define CREATE_TRACE_POINTS
> >   #include "bpf_testmod-events.h"
> >
> > +#define CONNECT_TIMEOUT_SEC 1
> > +
> >   typedef int (*func_proto_typedef)(long);
> >   typedef int (*func_proto_typedef_nested1)(func_proto_typedef);
> >   typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1);
> >
> >   DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123;
> >   long bpf_testmod_test_struct_arg_result;
> > +static struct socket *sock;
> >
> >   struct bpf_testmod_struct_arg_1 {
> >       int a;
> > @@ -494,6 +505,124 @@ __bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused
> >       return arg;
> >   }
> >
> > +__bpf_kfunc int bpf_kfunc_init_sock(struct init_sock_args *args)
> > +{
> > +     int proto;
> > +
> > +     if (sock)
> > +             pr_warn("%s called without releasing old sock", __func__);
> > +
> > +     switch (args->af) {
> > +     case AF_INET:
> > +     case AF_INET6:
> > +             proto = args->type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP;
> > +             break;
> > +     case AF_UNIX:
> > +             proto = PF_UNIX;
> > +             break;
> > +     default:
> > +             pr_err("invalid address family %d\n", args->af);
> > +             return -EINVAL;
> > +     }
> > +
> > +     return sock_create_kern(&init_net, args->af, args->type, proto, &sock);
> > +}
> > +
> > +__bpf_kfunc void bpf_kfunc_close_sock(void)
> > +{
> > +     if (sock) {
> > +             sock_release(sock);
> > +             sock = NULL;
> > +     }
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_connect(struct addr_args *args)
> > +{
> > +     /* Set timeout for call to kernel_connect() to prevent it from hanging,
> > +      * and consider the connection attempt failed if it returns
> > +      * -EINPROGRESS.
> > +      */
> > +     sock->sk->sk_sndtimeo = CONNECT_TIMEOUT_SEC * HZ;
> > +
> > +     return kernel_connect(sock, (struct sockaddr *)&args->addr,
> > +                           args->addrlen, 0);
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_bind(struct addr_args *args)
> > +{
> > +     return kernel_bind(sock, (struct sockaddr *)&args->addr, args->addrlen);
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_listen(void)
> > +{
> > +     return kernel_listen(sock, 128);
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args)
> > +{
> > +     struct msghdr msg = {
> > +             .msg_name       = &args->addr.addr,
> > +             .msg_namelen    = args->addr.addrlen,
> > +     };
> > +     struct kvec iov;
> > +     int err;
> > +
> > +     iov.iov_base = args->msg;
> > +     iov.iov_len  = args->msglen;
>
> It would be better to check if args->msglen > sizeof(arg->msg) although
> this function is just for test cases. Same for args->addr.addrlen.
>
> > +
> > +     err = kernel_sendmsg(sock, &msg, &iov, 1, args->msglen);
> > +     args->addr.addrlen = msg.msg_namelen;
> > +
> > +     return err;
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args)
> > +{
> > +     struct msghdr msg = {
> > +             .msg_name       = &args->addr.addr,
> > +             .msg_namelen    = args->addr.addrlen,
> > +     };
> > +     struct kvec iov;
> > +     int err;
> > +
> > +     iov.iov_base = args->msg;
> > +     iov.iov_len  = args->msglen;
> > +
> > +     iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, args->msglen);
> > +     err = sock_sendmsg(sock, &msg);
> > +     args->addr.addrlen = msg.msg_namelen;
> > +
> > +     return err;
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_getsockname(struct addr_args *args)
> > +{
> > +     int err;
> > +
> > +     err = kernel_getsockname(sock, (struct sockaddr *)&args->addr);
> > +     if (err < 0)
> > +             goto out;
> > +
> > +     args->addrlen = err;
> > +     err = 0;
> > +out:
> > +     return err;
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_getpeername(struct addr_args *args)
> > +{
> > +     int err;
> > +
> > +     err = kernel_getpeername(sock, (struct sockaddr *)&args->addr);
> > +     if (err < 0)
> > +             goto out;
> > +
> > +     args->addrlen = err;
> > +     err = 0;
> > +out:
> > +     return err;
> > +}
> > +
> >   BTF_KFUNCS_START(bpf_testmod_check_kfunc_ids)
> >   BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc)
> >   BTF_ID_FLAGS(func, bpf_kfunc_call_test1)
> > @@ -520,6 +649,15 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS | KF_RCU)
> >   BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE)
> >   BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg)
> >   BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset)
> > +BTF_ID_FLAGS(func, bpf_kfunc_init_sock)
> > +BTF_ID_FLAGS(func, bpf_kfunc_close_sock)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_connect)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_bind)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_listen)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_sendmsg)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_sock_sendmsg)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getsockname)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getpeername)
> >   BTF_KFUNCS_END(bpf_testmod_check_kfunc_ids)
> >
> >   static int bpf_testmod_ops_init(struct btf *btf)
> > @@ -650,6 +788,7 @@ static int bpf_testmod_init(void)
> >               return ret;
> >       if (bpf_fentry_test1(0) < 0)
> >               return -EINVAL;
> > +     sock = NULL;
> >       return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file);
> >   }
> >
> > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> > index 7c664dd610597..cdf7769a7d8ca 100644
> > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> > @@ -64,6 +64,22 @@ struct prog_test_fail3 {
> >       char arr2[];
> >   };
> >
> > +struct init_sock_args {
> > +     int af;
> > +     int type;
> > +};
> > +
> > +struct addr_args {
> > +     char addr[sizeof(struct __kernel_sockaddr_storage)];
> > +     int addrlen;
> > +};
> > +
> > +struct sendmsg_args {
> > +     struct addr_args addr;
> > +     char msg[10];
> > +     int msglen;
> > +};
> > +
> >   struct prog_test_ref_kfunc *
> >   bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym;
> >   void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
> > @@ -106,4 +122,15 @@ void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p);
> >   void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len);
> >
> >   void bpf_kfunc_common_test(void) __ksym;
> > +
> > +int bpf_kfunc_init_sock(struct init_sock_args *args) __ksym;
> > +void bpf_kfunc_close_sock(void) __ksym;
> > +int bpf_kfunc_call_kernel_connect(struct addr_args *args) __ksym;
> > +int bpf_kfunc_call_kernel_bind(struct addr_args *args) __ksym;
> > +int bpf_kfunc_call_kernel_listen(void) __ksym;
> > +int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) __ksym;
> > +int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) __ksym;
> > +int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) __ksym;
> > +int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) __ksym;
> > +
> >   #endif /* _BPF_TESTMOD_KFUNC_H */
Martin KaFai Lau April 16, 2024, 6:43 a.m. UTC | #3 
On 4/12/24 9:52 AM, Jordan Rife wrote:
> This patch adds a set of kfuncs to bpf_testmod that can be used to
> manipulate a socket from kernel space.
> 
> Signed-off-by: Jordan Rife <jrife@google.com>
> ---
>   .../selftests/bpf/bpf_testmod/bpf_testmod.c   | 139 ++++++++++++++++++
>   .../bpf/bpf_testmod/bpf_testmod_kfunc.h       |  27 ++++
>   2 files changed, 166 insertions(+)
> 
> diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> index 39ad96a18123f..663df8148097e 100644
> --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> @@ -10,18 +10,29 @@
>   #include <linux/percpu-defs.h>
>   #include <linux/sysfs.h>
>   #include <linux/tracepoint.h>
> +#include <linux/net.h>
> +#include <linux/socket.h>
> +#include <linux/nsproxy.h>
> +#include <linux/inet.h>
> +#include <linux/in.h>
> +#include <linux/in6.h>
> +#include <linux/un.h>
> +#include <net/sock.h>
>   #include "bpf_testmod.h"
>   #include "bpf_testmod_kfunc.h"
>   
>   #define CREATE_TRACE_POINTS
>   #include "bpf_testmod-events.h"
>   
> +#define CONNECT_TIMEOUT_SEC 1
> +
>   typedef int (*func_proto_typedef)(long);
>   typedef int (*func_proto_typedef_nested1)(func_proto_typedef);
>   typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1);
>   
>   DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123;
>   long bpf_testmod_test_struct_arg_result;
> +static struct socket *sock;
>   
>   struct bpf_testmod_struct_arg_1 {
>   	int a;
> @@ -494,6 +505,124 @@ __bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused
>   	return arg;
>   }
>   
> +__bpf_kfunc int bpf_kfunc_init_sock(struct init_sock_args *args)
> +{
> +	int proto;
> +
> +	if (sock)
> +		pr_warn("%s called without releasing old sock", __func__);

hmm...this global sock pointer is quite unease. e.g. what if multiple tasks 
trying to use init/close/connect... in parallel.

Storing sock in a bpf map will be better but that may be overkill for testing. 
Can a separate global lock/mutex (not the lock_sock) be acquired first before 
using the sock pointer in the kfuncs?

> +
> +	switch (args->af) {
> +	case AF_INET:
> +	case AF_INET6:
> +		proto = args->type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP;
> +		break;
> +	case AF_UNIX:
> +		proto = PF_UNIX;
> +		break;
> +	default:
> +		pr_err("invalid address family %d\n", args->af);
> +		return -EINVAL;
> +	}
> +
> +	return sock_create_kern(&init_net, args->af, args->type, proto, &sock);
> +}
> +
> +__bpf_kfunc void bpf_kfunc_close_sock(void)
> +{
> +	if (sock) {
> +		sock_release(sock);

bpf_testmod_exit() should probably do this NULL check and sock_release() also.

> +		sock = NULL;
> +	}
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_connect(struct addr_args *args)
> +{
> +	/* Set timeout for call to kernel_connect() to prevent it from hanging,
> +	 * and consider the connection attempt failed if it returns
> +	 * -EINPROGRESS.
> +	 */
> +	sock->sk->sk_sndtimeo = CONNECT_TIMEOUT_SEC * HZ;

Is it better to set sk_sndtimeo in bpf_kfunc_init_sock() ?

> +
> +	return kernel_connect(sock, (struct sockaddr *)&args->addr,
> +			      args->addrlen, 0);
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_bind(struct addr_args *args)
> +{
> +	return kernel_bind(sock, (struct sockaddr *)&args->addr, args->addrlen);
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_listen(void)
> +{
> +	return kernel_listen(sock, 128);
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args)
> +{
> +	struct msghdr msg = {
> +		.msg_name	= &args->addr.addr,
> +		.msg_namelen	= args->addr.addrlen,
> +	};
> +	struct kvec iov;
> +	int err;
> +
> +	iov.iov_base = args->msg;
> +	iov.iov_len  = args->msglen;
> +
> +	err = kernel_sendmsg(sock, &msg, &iov, 1, args->msglen);
> +	args->addr.addrlen = msg.msg_namelen;
> +
> +	return err;
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args)
> +{
> +	struct msghdr msg = {
> +		.msg_name	= &args->addr.addr,
> +		.msg_namelen	= args->addr.addrlen,
> +	};
> +	struct kvec iov;
> +	int err;
> +
> +	iov.iov_base = args->msg;
> +	iov.iov_len  = args->msglen;
> +
> +	iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, args->msglen);
> +	err = sock_sendmsg(sock, &msg);
> +	args->addr.addrlen = msg.msg_namelen;
> +
> +	return err;
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_getsockname(struct addr_args *args)
> +{
> +	int err;
> +
> +	err = kernel_getsockname(sock, (struct sockaddr *)&args->addr);
> +	if (err < 0)
> +		goto out;
> +
> +	args->addrlen = err;
> +	err = 0;
> +out:
> +	return err;
> +}
> +
> +__bpf_kfunc int bpf_kfunc_call_kernel_getpeername(struct addr_args *args)
> +{
> +	int err;
> +
> +	err = kernel_getpeername(sock, (struct sockaddr *)&args->addr);
> +	if (err < 0)
> +		goto out;
> +
> +	args->addrlen = err;
> +	err = 0;
> +out:
> +	return err;
> +}
> +
>   BTF_KFUNCS_START(bpf_testmod_check_kfunc_ids)
>   BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc)
>   BTF_ID_FLAGS(func, bpf_kfunc_call_test1)
> @@ -520,6 +649,15 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS | KF_RCU)
>   BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE)
>   BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg)
>   BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset)
> +BTF_ID_FLAGS(func, bpf_kfunc_init_sock)
> +BTF_ID_FLAGS(func, bpf_kfunc_close_sock)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_connect)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_bind)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_listen)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_sendmsg)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_sock_sendmsg)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getsockname)
> +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getpeername)

All these new kfunc should have the KF_SLEEPABLE flag.

>   BTF_KFUNCS_END(bpf_testmod_check_kfunc_ids)
>   
>   static int bpf_testmod_ops_init(struct btf *btf)
> @@ -650,6 +788,7 @@ static int bpf_testmod_init(void)
>   		return ret;
>   	if (bpf_fentry_test1(0) < 0)
>   		return -EINVAL;
> +	sock = NULL;
>   	return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file);
>   }
>   
> diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> index 7c664dd610597..cdf7769a7d8ca 100644
> --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> @@ -64,6 +64,22 @@ struct prog_test_fail3 {
>   	char arr2[];
>   };
>   
> +struct init_sock_args {
> +	int af;
> +	int type;
> +};
> +
> +struct addr_args {
> +	char addr[sizeof(struct __kernel_sockaddr_storage)];

nit. Can "struct sockaddr_storage addr;" be directly used instead of a char array?

> +	int addrlen;
> +};
> +
> +struct sendmsg_args {
> +	struct addr_args addr;
> +	char msg[10];
> +	int msglen;
> +};
> +
>   struct prog_test_ref_kfunc *
>   bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym;
>   void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
> @@ -106,4 +122,15 @@ void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p);
>   void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len);
>   
>   void bpf_kfunc_common_test(void) __ksym;
> +
> +int bpf_kfunc_init_sock(struct init_sock_args *args) __ksym;
> +void bpf_kfunc_close_sock(void) __ksym;
> +int bpf_kfunc_call_kernel_connect(struct addr_args *args) __ksym;
> +int bpf_kfunc_call_kernel_bind(struct addr_args *args) __ksym;
> +int bpf_kfunc_call_kernel_listen(void) __ksym;
> +int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) __ksym;
> +int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) __ksym;
> +int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) __ksym;
> +int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) __ksym;
> +
>   #endif /* _BPF_TESTMOD_KFUNC_H */
Jordan Rife April 17, 2024, 4:59 p.m. UTC | #4 
Martin,

Thank you for the detailed feedback.

> Can a separate global lock/mutex (not the lock_sock) be acquired first before
> using the sock pointer in the kfuncs?

Sure. I will add the mutex around the socket operations. As for the
single global sock pointer, I wanted to keep it simple in this patch
series to fulfill the current use case. I agree it might be overkill
for now to add the bpf map and such.

> Is it better to set sk_sndtimeo in bpf_kfunc_init_sock() ?
> All these new kfunc should have the KF_SLEEPABLE flag.
> bpf_testmod_exit() should probably do this NULL check and sock_release() also.

Ack. I will add this.

> nit. Can "struct sockaddr_storage addr;" be directly used instead of a char array?

When using "struct sockaddr_storage addr;" directly, the BPF program
fails to load with the following error message.

> libbpf: prog 'kernel_connect': BPF program load failed: Invalid argument
> libbpf: prog 'kernel_connect': -- BEGIN PROG LOAD LOG --
> 0: R1=ctx() R10=fp0
> ; return bpf_kfunc_call_kernel_connect(args); @ sock_addr_kern.c:26
> 0: (85) call bpf_kfunc_call_kernel_connect#99994
> arg#0 pointer type STRUCT addr_args must point to scalar, or struct with scalar
> processed 1 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
> -- END PROG LOAD LOG --
> libbpf: prog 'kernel_connect': failed to load: -22
> libbpf: failed to load object 'sock_addr_kern'
> libbpf: failed to load BPF skeleton 'sock_addr_kern': -22
> load_sock_addr_kern:FAIL:skel unexpected error: -22
> test_sock_addr:FAIL:load_sock_addr_kern unexpected error: -1 (errno 22)
> #288 sock_addr:FAIL

-Jordan

On Tue, Apr 16, 2024 at 2:43 AM Martin KaFai Lau <martin.lau@linux.dev> wrote:
>
> On 4/12/24 9:52 AM, Jordan Rife wrote:
> > This patch adds a set of kfuncs to bpf_testmod that can be used to
> > manipulate a socket from kernel space.
> >
> > Signed-off-by: Jordan Rife <jrife@google.com>
> > ---
> >   .../selftests/bpf/bpf_testmod/bpf_testmod.c   | 139 ++++++++++++++++++
> >   .../bpf/bpf_testmod/bpf_testmod_kfunc.h       |  27 ++++
> >   2 files changed, 166 insertions(+)
> >
> > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > index 39ad96a18123f..663df8148097e 100644
> > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > @@ -10,18 +10,29 @@
> >   #include <linux/percpu-defs.h>
> >   #include <linux/sysfs.h>
> >   #include <linux/tracepoint.h>
> > +#include <linux/net.h>
> > +#include <linux/socket.h>
> > +#include <linux/nsproxy.h>
> > +#include <linux/inet.h>
> > +#include <linux/in.h>
> > +#include <linux/in6.h>
> > +#include <linux/un.h>
> > +#include <net/sock.h>
> >   #include "bpf_testmod.h"
> >   #include "bpf_testmod_kfunc.h"
> >
> >   #define CREATE_TRACE_POINTS
> >   #include "bpf_testmod-events.h"
> >
> > +#define CONNECT_TIMEOUT_SEC 1
> > +
> >   typedef int (*func_proto_typedef)(long);
> >   typedef int (*func_proto_typedef_nested1)(func_proto_typedef);
> >   typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1);
> >
> >   DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123;
> >   long bpf_testmod_test_struct_arg_result;
> > +static struct socket *sock;
> >
> >   struct bpf_testmod_struct_arg_1 {
> >       int a;
> > @@ -494,6 +505,124 @@ __bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused
> >       return arg;
> >   }
> >
> > +__bpf_kfunc int bpf_kfunc_init_sock(struct init_sock_args *args)
> > +{
> > +     int proto;
> > +
> > +     if (sock)
> > +             pr_warn("%s called without releasing old sock", __func__);
>
> hmm...this global sock pointer is quite unease. e.g. what if multiple tasks
> trying to use init/close/connect... in parallel.
>
> Storing sock in a bpf map will be better but that may be overkill for testing.
> Can a separate global lock/mutex (not the lock_sock) be acquired first before
> using the sock pointer in the kfuncs?
>
> > +
> > +     switch (args->af) {
> > +     case AF_INET:
> > +     case AF_INET6:
> > +             proto = args->type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP;
> > +             break;
> > +     case AF_UNIX:
> > +             proto = PF_UNIX;
> > +             break;
> > +     default:
> > +             pr_err("invalid address family %d\n", args->af);
> > +             return -EINVAL;
> > +     }
> > +
> > +     return sock_create_kern(&init_net, args->af, args->type, proto, &sock);
> > +}
> > +
> > +__bpf_kfunc void bpf_kfunc_close_sock(void)
> > +{
> > +     if (sock) {
> > +             sock_release(sock);
>
> bpf_testmod_exit() should probably do this NULL check and sock_release() also.
>
> > +             sock = NULL;
> > +     }
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_connect(struct addr_args *args)
> > +{
> > +     /* Set timeout for call to kernel_connect() to prevent it from hanging,
> > +      * and consider the connection attempt failed if it returns
> > +      * -EINPROGRESS.
> > +      */
> > +     sock->sk->sk_sndtimeo = CONNECT_TIMEOUT_SEC * HZ;
>
> Is it better to set sk_sndtimeo in bpf_kfunc_init_sock() ?
>
> > +
> > +     return kernel_connect(sock, (struct sockaddr *)&args->addr,
> > +                           args->addrlen, 0);
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_bind(struct addr_args *args)
> > +{
> > +     return kernel_bind(sock, (struct sockaddr *)&args->addr, args->addrlen);
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_listen(void)
> > +{
> > +     return kernel_listen(sock, 128);
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args)
> > +{
> > +     struct msghdr msg = {
> > +             .msg_name       = &args->addr.addr,
> > +             .msg_namelen    = args->addr.addrlen,
> > +     };
> > +     struct kvec iov;
> > +     int err;
> > +
> > +     iov.iov_base = args->msg;
> > +     iov.iov_len  = args->msglen;
> > +
> > +     err = kernel_sendmsg(sock, &msg, &iov, 1, args->msglen);
> > +     args->addr.addrlen = msg.msg_namelen;
> > +
> > +     return err;
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args)
> > +{
> > +     struct msghdr msg = {
> > +             .msg_name       = &args->addr.addr,
> > +             .msg_namelen    = args->addr.addrlen,
> > +     };
> > +     struct kvec iov;
> > +     int err;
> > +
> > +     iov.iov_base = args->msg;
> > +     iov.iov_len  = args->msglen;
> > +
> > +     iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, args->msglen);
> > +     err = sock_sendmsg(sock, &msg);
> > +     args->addr.addrlen = msg.msg_namelen;
> > +
> > +     return err;
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_getsockname(struct addr_args *args)
> > +{
> > +     int err;
> > +
> > +     err = kernel_getsockname(sock, (struct sockaddr *)&args->addr);
> > +     if (err < 0)
> > +             goto out;
> > +
> > +     args->addrlen = err;
> > +     err = 0;
> > +out:
> > +     return err;
> > +}
> > +
> > +__bpf_kfunc int bpf_kfunc_call_kernel_getpeername(struct addr_args *args)
> > +{
> > +     int err;
> > +
> > +     err = kernel_getpeername(sock, (struct sockaddr *)&args->addr);
> > +     if (err < 0)
> > +             goto out;
> > +
> > +     args->addrlen = err;
> > +     err = 0;
> > +out:
> > +     return err;
> > +}
> > +
> >   BTF_KFUNCS_START(bpf_testmod_check_kfunc_ids)
> >   BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc)
> >   BTF_ID_FLAGS(func, bpf_kfunc_call_test1)
> > @@ -520,6 +649,15 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS | KF_RCU)
> >   BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE)
> >   BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg)
> >   BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset)
> > +BTF_ID_FLAGS(func, bpf_kfunc_init_sock)
> > +BTF_ID_FLAGS(func, bpf_kfunc_close_sock)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_connect)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_bind)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_listen)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_sendmsg)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_sock_sendmsg)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getsockname)
> > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getpeername)
>
> All these new kfunc should have the KF_SLEEPABLE flag.
>
> >   BTF_KFUNCS_END(bpf_testmod_check_kfunc_ids)
> >
> >   static int bpf_testmod_ops_init(struct btf *btf)
> > @@ -650,6 +788,7 @@ static int bpf_testmod_init(void)
> >               return ret;
> >       if (bpf_fentry_test1(0) < 0)
> >               return -EINVAL;
> > +     sock = NULL;
> >       return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file);
> >   }
> >
> > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> > index 7c664dd610597..cdf7769a7d8ca 100644
> > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
> > @@ -64,6 +64,22 @@ struct prog_test_fail3 {
> >       char arr2[];
> >   };
> >
> > +struct init_sock_args {
> > +     int af;
> > +     int type;
> > +};
> > +
> > +struct addr_args {
> > +     char addr[sizeof(struct __kernel_sockaddr_storage)];
>
> nit. Can "struct sockaddr_storage addr;" be directly used instead of a char array?
>
> > +     int addrlen;
> > +};
> > +
> > +struct sendmsg_args {
> > +     struct addr_args addr;
> > +     char msg[10];
> > +     int msglen;
> > +};
> > +
> >   struct prog_test_ref_kfunc *
> >   bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym;
> >   void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
> > @@ -106,4 +122,15 @@ void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p);
> >   void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len);
> >
> >   void bpf_kfunc_common_test(void) __ksym;
> > +
> > +int bpf_kfunc_init_sock(struct init_sock_args *args) __ksym;
> > +void bpf_kfunc_close_sock(void) __ksym;
> > +int bpf_kfunc_call_kernel_connect(struct addr_args *args) __ksym;
> > +int bpf_kfunc_call_kernel_bind(struct addr_args *args) __ksym;
> > +int bpf_kfunc_call_kernel_listen(void) __ksym;
> > +int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) __ksym;
> > +int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) __ksym;
> > +int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) __ksym;
> > +int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) __ksym;
> > +
> >   #endif /* _BPF_TESTMOD_KFUNC_H */
>
Kui-Feng Lee May 1, 2024, 9:54 p.m. UTC | #5 
On 4/17/24 09:59, Jordan Rife wrote:
>> nit. Can "struct sockaddr_storage addr;" be directly used instead of a char array?
> When using "struct sockaddr_storage addr;" directly, the BPF program
> fails to load with the following error message.
> 
>> libbpf: prog 'kernel_connect': BPF program load failed: Invalid argument
>> libbpf: prog 'kernel_connect': -- BEGIN PROG LOAD LOG --
>> 0: R1=ctx() R10=fp0
>> ; return bpf_kfunc_call_kernel_connect(args); @ sock_addr_kern.c:26
>> 0: (85) call bpf_kfunc_call_kernel_connect#99994
>> arg#0 pointer type STRUCT addr_args must point to scalar, or struct with scalar
>> processed 1 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
>> -- END PROG LOAD LOG --
>> libbpf: prog 'kernel_connect': failed to load: -22
>> libbpf: failed to load object 'sock_addr_kern'
>> libbpf: failed to load BPF skeleton 'sock_addr_kern': -22
>> load_sock_addr_kern:FAIL:skel unexpected error: -22
>> test_sock_addr:FAIL:load_sock_addr_kern unexpected error: -1 (errno 22)
>> #288 sock_addr:FAIL

I just looked into the definition of struct __kernel_sockaddr_sotrage
and the change log of this type. It has a pointer in it, causing this
error. According to the commit log, the pointer is there to fix an
alignment issue. I am curious if we can replace the pointer with
intptr_t to fix this error.

Of course, this should not block this patch set.
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
index 39ad96a18123f..663df8148097e 100644
--- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
+++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
@@ -10,18 +10,29 @@ 
 #include <linux/percpu-defs.h>
 #include <linux/sysfs.h>
 #include <linux/tracepoint.h>
+#include <linux/net.h>
+#include <linux/socket.h>
+#include <linux/nsproxy.h>
+#include <linux/inet.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/un.h>
+#include <net/sock.h>
 #include "bpf_testmod.h"
 #include "bpf_testmod_kfunc.h"
 
 #define CREATE_TRACE_POINTS
 #include "bpf_testmod-events.h"
 
+#define CONNECT_TIMEOUT_SEC 1
+
 typedef int (*func_proto_typedef)(long);
 typedef int (*func_proto_typedef_nested1)(func_proto_typedef);
 typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1);
 
 DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123;
 long bpf_testmod_test_struct_arg_result;
+static struct socket *sock;
 
 struct bpf_testmod_struct_arg_1 {
 	int a;
@@ -494,6 +505,124 @@  __bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused
 	return arg;
 }
 
+__bpf_kfunc int bpf_kfunc_init_sock(struct init_sock_args *args)
+{
+	int proto;
+
+	if (sock)
+		pr_warn("%s called without releasing old sock", __func__);
+
+	switch (args->af) {
+	case AF_INET:
+	case AF_INET6:
+		proto = args->type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP;
+		break;
+	case AF_UNIX:
+		proto = PF_UNIX;
+		break;
+	default:
+		pr_err("invalid address family %d\n", args->af);
+		return -EINVAL;
+	}
+
+	return sock_create_kern(&init_net, args->af, args->type, proto, &sock);
+}
+
+__bpf_kfunc void bpf_kfunc_close_sock(void)
+{
+	if (sock) {
+		sock_release(sock);
+		sock = NULL;
+	}
+}
+
+__bpf_kfunc int bpf_kfunc_call_kernel_connect(struct addr_args *args)
+{
+	/* Set timeout for call to kernel_connect() to prevent it from hanging,
+	 * and consider the connection attempt failed if it returns
+	 * -EINPROGRESS.
+	 */
+	sock->sk->sk_sndtimeo = CONNECT_TIMEOUT_SEC * HZ;
+
+	return kernel_connect(sock, (struct sockaddr *)&args->addr,
+			      args->addrlen, 0);
+}
+
+__bpf_kfunc int bpf_kfunc_call_kernel_bind(struct addr_args *args)
+{
+	return kernel_bind(sock, (struct sockaddr *)&args->addr, args->addrlen);
+}
+
+__bpf_kfunc int bpf_kfunc_call_kernel_listen(void)
+{
+	return kernel_listen(sock, 128);
+}
+
+__bpf_kfunc int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args)
+{
+	struct msghdr msg = {
+		.msg_name	= &args->addr.addr,
+		.msg_namelen	= args->addr.addrlen,
+	};
+	struct kvec iov;
+	int err;
+
+	iov.iov_base = args->msg;
+	iov.iov_len  = args->msglen;
+
+	err = kernel_sendmsg(sock, &msg, &iov, 1, args->msglen);
+	args->addr.addrlen = msg.msg_namelen;
+
+	return err;
+}
+
+__bpf_kfunc int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args)
+{
+	struct msghdr msg = {
+		.msg_name	= &args->addr.addr,
+		.msg_namelen	= args->addr.addrlen,
+	};
+	struct kvec iov;
+	int err;
+
+	iov.iov_base = args->msg;
+	iov.iov_len  = args->msglen;
+
+	iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, args->msglen);
+	err = sock_sendmsg(sock, &msg);
+	args->addr.addrlen = msg.msg_namelen;
+
+	return err;
+}
+
+__bpf_kfunc int bpf_kfunc_call_kernel_getsockname(struct addr_args *args)
+{
+	int err;
+
+	err = kernel_getsockname(sock, (struct sockaddr *)&args->addr);
+	if (err < 0)
+		goto out;
+
+	args->addrlen = err;
+	err = 0;
+out:
+	return err;
+}
+
+__bpf_kfunc int bpf_kfunc_call_kernel_getpeername(struct addr_args *args)
+{
+	int err;
+
+	err = kernel_getpeername(sock, (struct sockaddr *)&args->addr);
+	if (err < 0)
+		goto out;
+
+	args->addrlen = err;
+	err = 0;
+out:
+	return err;
+}
+
 BTF_KFUNCS_START(bpf_testmod_check_kfunc_ids)
 BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc)
 BTF_ID_FLAGS(func, bpf_kfunc_call_test1)
@@ -520,6 +649,15 @@  BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS | KF_RCU)
 BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE)
 BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg)
 BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset)
+BTF_ID_FLAGS(func, bpf_kfunc_init_sock)
+BTF_ID_FLAGS(func, bpf_kfunc_close_sock)
+BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_connect)
+BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_bind)
+BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_listen)
+BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_sendmsg)
+BTF_ID_FLAGS(func, bpf_kfunc_call_sock_sendmsg)
+BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getsockname)
+BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getpeername)
 BTF_KFUNCS_END(bpf_testmod_check_kfunc_ids)
 
 static int bpf_testmod_ops_init(struct btf *btf)
@@ -650,6 +788,7 @@  static int bpf_testmod_init(void)
 		return ret;
 	if (bpf_fentry_test1(0) < 0)
 		return -EINVAL;
+	sock = NULL;
 	return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file);
 }
 
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
index 7c664dd610597..cdf7769a7d8ca 100644
--- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
+++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h
@@ -64,6 +64,22 @@  struct prog_test_fail3 {
 	char arr2[];
 };
 
+struct init_sock_args {
+	int af;
+	int type;
+};
+
+struct addr_args {
+	char addr[sizeof(struct __kernel_sockaddr_storage)];
+	int addrlen;
+};
+
+struct sendmsg_args {
+	struct addr_args addr;
+	char msg[10];
+	int msglen;
+};
+
 struct prog_test_ref_kfunc *
 bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym;
 void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
@@ -106,4 +122,15 @@  void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p);
 void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len);
 
 void bpf_kfunc_common_test(void) __ksym;
+
+int bpf_kfunc_init_sock(struct init_sock_args *args) __ksym;
+void bpf_kfunc_close_sock(void) __ksym;
+int bpf_kfunc_call_kernel_connect(struct addr_args *args) __ksym;
+int bpf_kfunc_call_kernel_bind(struct addr_args *args) __ksym;
+int bpf_kfunc_call_kernel_listen(void) __ksym;
+int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) __ksym;
+int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) __ksym;
+int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) __ksym;
+int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) __ksym;
+
 #endif /* _BPF_TESTMOD_KFUNC_H */