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samples/bpf, selftests/bpf: Use bpf_probe_read_kernel

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A handful of samples and selftests fail to build on s390, because
after commit 0ebeea8ca8 ("bpf: Restrict bpf_probe_read{, str}()
only to archs where they work") bpf_probe_read is not available
anymore.

Fix by using bpf_probe_read_kernel.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720114806.88823-1-iii@linux.ibm.com
This commit is contained in:
Ilya Leoshkevich 2020-07-20 13:48:06 +02:00 committed by Alexei Starovoitov
parent 6bd557275a
commit e4d9c23207
10 changed files with 33 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
samples/bpf/offwaketime_kern.c
View File

@ -12,7 +12,12 @@
#include <bpf/bpf_helpers.h> #include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h> #include <bpf/bpf_tracing.h>
#define _(P) ({typeof(P) val; bpf_probe_read(&val, sizeof(val), &P); val;}) #define _(P) \
({ \
typeof(P) val; \
bpf_probe_read_kernel(&val, sizeof(val), &(P)); \
val; \
})
#define MINBLOCK_US 1 #define MINBLOCK_US 1

12
samples/bpf/test_overhead_kprobe_kern.c
View File

@ -10,7 +10,12 @@
#include <bpf/bpf_helpers.h> #include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h> #include <bpf/bpf_tracing.h>
#define _(P) ({typeof(P) val = 0; bpf_probe_read(&val, sizeof(val), &P); val;}) #define _(P) \
({ \
typeof(P) val = 0; \
bpf_probe_read_kernel(&val, sizeof(val), &(P)); \
val; \
})
SEC("kprobe/__set_task_comm") SEC("kprobe/__set_task_comm")
int prog(struct pt_regs *ctx) int prog(struct pt_regs *ctx)
@ -25,8 +30,9 @@ int prog(struct pt_regs *ctx)
tsk = (void *)PT_REGS_PARM1(ctx); tsk = (void *)PT_REGS_PARM1(ctx);
pid = _(tsk->pid); pid = _(tsk->pid);
bpf_probe_read(oldcomm, sizeof(oldcomm), &tsk->comm); bpf_probe_read_kernel(oldcomm, sizeof(oldcomm), &tsk->comm);
bpf_probe_read(newcomm, sizeof(newcomm), (void *)PT_REGS_PARM2(ctx)); bpf_probe_read_kernel(newcomm, sizeof(newcomm),
(void *)PT_REGS_PARM2(ctx));
signal = _(tsk->signal); signal = _(tsk->signal);
oom_score_adj = _(signal->oom_score_adj); oom_score_adj = _(signal->oom_score_adj);
return 0; return 0;

9
samples/bpf/tracex1_kern.c
View File

@ -11,7 +11,12 @@
#include <bpf/bpf_helpers.h> #include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h> #include <bpf/bpf_tracing.h>
#define _(P) ({typeof(P) val = 0; bpf_probe_read(&val, sizeof(val), &P); val;}) #define _(P) \
({ \
typeof(P) val = 0; \
bpf_probe_read_kernel(&val, sizeof(val), &(P)); \
val; \
})
/* kprobe is NOT a stable ABI /* kprobe is NOT a stable ABI
* kernel functions can be removed, renamed or completely change semantics. * kernel functions can be removed, renamed or completely change semantics.
@ -34,7 +39,7 @@ int bpf_prog1(struct pt_regs *ctx)
dev = _(skb->dev); dev = _(skb->dev);
len = _(skb->len); len = _(skb->len);
bpf_probe_read(devname, sizeof(devname), dev->name); bpf_probe_read_kernel(devname, sizeof(devname), dev->name);
if (devname[0] == 'l' && devname[1] == 'o') { if (devname[0] == 'l' && devname[1] == 'o') {
char fmt[] = "skb %p len %d\n"; char fmt[] = "skb %p len %d\n";

4
samples/bpf/tracex5_kern.c
View File

@ -47,7 +47,7 @@ PROG(SYS__NR_write)(struct pt_regs *ctx)
{ {
struct seccomp_data sd; struct seccomp_data sd;
bpf_probe_read(&sd, sizeof(sd), (void *)PT_REGS_PARM2(ctx)); bpf_probe_read_kernel(&sd, sizeof(sd), (void *)PT_REGS_PARM2(ctx));
if (sd.args[2] == 512) { if (sd.args[2] == 512) {
char fmt[] = "write(fd=%d, buf=%p, size=%d)\n"; char fmt[] = "write(fd=%d, buf=%p, size=%d)\n";
bpf_trace_printk(fmt, sizeof(fmt), bpf_trace_printk(fmt, sizeof(fmt),
@ -60,7 +60,7 @@ PROG(SYS__NR_read)(struct pt_regs *ctx)
{ {
struct seccomp_data sd; struct seccomp_data sd;
bpf_probe_read(&sd, sizeof(sd), (void *)PT_REGS_PARM2(ctx)); bpf_probe_read_kernel(&sd, sizeof(sd), (void *)PT_REGS_PARM2(ctx));
if (sd.args[2] > 128 && sd.args[2] <= 1024) { if (sd.args[2] > 128 && sd.args[2] <= 1024) {
char fmt[] = "read(fd=%d, buf=%p, size=%d)\n"; char fmt[] = "read(fd=%d, buf=%p, size=%d)\n";
bpf_trace_printk(fmt, sizeof(fmt), bpf_trace_printk(fmt, sizeof(fmt),

3
tools/bpf/bpftool/skeleton/pid_iter.bpf.c
View File

@ -71,7 +71,8 @@ int iter(struct bpf_iter__task_file *ctx)
e.pid = task->tgid; e.pid = task->tgid;
e.id = get_obj_id(file->private_data, obj_type); e.id = get_obj_id(file->private_data, obj_type);
bpf_probe_read(&e.comm, sizeof(e.comm), task->group_leader->comm); bpf_probe_read_kernel(&e.comm, sizeof(e.comm),
task->group_leader->comm);
bpf_seq_write(ctx->meta->seq, &e, sizeof(e)); bpf_seq_write(ctx->meta->seq, &e, sizeof(e));
return 0; return 0;

6
tools/testing/selftests/bpf/progs/bpf_iter_netlink.c
View File

@ -36,10 +36,10 @@ int dump_netlink(struct bpf_iter__netlink *ctx)
if (!nlk->groups) { if (!nlk->groups) {
group = 0; group = 0;
} else { } else {
/* FIXME: temporary use bpf_probe_read here, needs /* FIXME: temporary use bpf_probe_read_kernel here, needs
* verifier support to do direct access. * verifier support to do direct access.
*/ */
bpf_probe_read(&group, sizeof(group), &nlk->groups[0]); bpf_probe_read_kernel(&group, sizeof(group), &nlk->groups[0]);
} }
BPF_SEQ_PRINTF(seq, "%-10u %08x %-8d %-8d %-5d %-8d ", BPF_SEQ_PRINTF(seq, "%-10u %08x %-8d %-8d %-5d %-8d ",
nlk->portid, (u32)group, nlk->portid, (u32)group,
@ -56,7 +56,7 @@ int dump_netlink(struct bpf_iter__netlink *ctx)
* with current verifier. * with current verifier.
*/ */
inode = SOCK_INODE(sk); inode = SOCK_INODE(sk);
bpf_probe_read(&ino, sizeof(ino), &inode->i_ino); bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
} }
BPF_SEQ_PRINTF(seq, "%-8u %-8lu\n", s->sk_drops.counter, ino); BPF_SEQ_PRINTF(seq, "%-8u %-8lu\n", s->sk_drops.counter, ino);

2
tools/testing/selftests/bpf/progs/bpf_iter_tcp4.c
View File

@ -57,7 +57,7 @@ static long sock_i_ino(const struct sock *sk)
return 0; return 0;
inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode; inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
bpf_probe_read(&ino, sizeof(ino), &inode->i_ino); bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
return ino; return ino;
} }

2
tools/testing/selftests/bpf/progs/bpf_iter_tcp6.c
View File

@ -57,7 +57,7 @@ static long sock_i_ino(const struct sock *sk)
return 0; return 0;
inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode; inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
bpf_probe_read(&ino, sizeof(ino), &inode->i_ino); bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
return ino; return ino;
} }

2
tools/testing/selftests/bpf/progs/bpf_iter_udp4.c
View File

@ -18,7 +18,7 @@ static long sock_i_ino(const struct sock *sk)
return 0; return 0;
inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode; inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
bpf_probe_read(&ino, sizeof(ino), &inode->i_ino); bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
return ino; return ino;
} }

2
tools/testing/selftests/bpf/progs/bpf_iter_udp6.c
View File

@ -25,7 +25,7 @@ static long sock_i_ino(const struct sock *sk)
return 0; return 0;
inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode; inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
bpf_probe_read(&ino, sizeof(ino), &inode->i_ino); bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
return ino; return ino;
} }