diff options
| -rw-r--r-- | include/uapi/linux/ptrace.h | 4 | ||||
| -rw-r--r-- | kernel/seccomp.c | 6 | ||||
| -rw-r--r-- | tools/testing/selftests/seccomp/seccomp_bpf.c | 61 |
3 files changed, 67 insertions, 4 deletions
diff --git a/include/uapi/linux/ptrace.h b/include/uapi/linux/ptrace.h index e46d82b91166..d5a1b8a492b9 100644 --- a/include/uapi/linux/ptrace.h +++ b/include/uapi/linux/ptrace.h @@ -69,8 +69,8 @@ struct ptrace_peeksiginfo_args { #define PTRACE_SECCOMP_GET_METADATA 0x420d struct seccomp_metadata { - unsigned long filter_off; /* Input: which filter */ - unsigned int flags; /* Output: filter's flags */ + __u64 filter_off; /* Input: which filter */ + __u64 flags; /* Output: filter's flags */ }; /* Read signals from a shared (process wide) queue */ diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 940fa408a288..dc77548167ef 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -1076,14 +1076,16 @@ long seccomp_get_metadata(struct task_struct *task, size = min_t(unsigned long, size, sizeof(kmd)); - if (copy_from_user(&kmd, data, size)) + if (size < sizeof(kmd.filter_off)) + return -EINVAL; + + if (copy_from_user(&kmd.filter_off, data, sizeof(kmd.filter_off))) return -EFAULT; filter = get_nth_filter(task, kmd.filter_off); if (IS_ERR(filter)) return PTR_ERR(filter); - memset(&kmd, 0, sizeof(kmd)); if (filter->log) kmd.flags |= SECCOMP_FILTER_FLAG_LOG; diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c index 0b457e8e0f0c..5df609950a66 100644 --- a/tools/testing/selftests/seccomp/seccomp_bpf.c +++ b/tools/testing/selftests/seccomp/seccomp_bpf.c @@ -141,6 +141,15 @@ struct seccomp_data { #define SECCOMP_FILTER_FLAG_LOG 2 #endif +#ifndef PTRACE_SECCOMP_GET_METADATA +#define PTRACE_SECCOMP_GET_METADATA 0x420d + +struct seccomp_metadata { + __u64 filter_off; /* Input: which filter */ + __u64 flags; /* Output: filter's flags */ +}; +#endif + #ifndef seccomp int seccomp(unsigned int op, unsigned int flags, void *args) { @@ -2845,6 +2854,58 @@ TEST(get_action_avail) EXPECT_EQ(errno, EOPNOTSUPP); } +TEST(get_metadata) +{ + pid_t pid; + int pipefd[2]; + char buf; + struct seccomp_metadata md; + + ASSERT_EQ(0, pipe(pipefd)); + + pid = fork(); + ASSERT_GE(pid, 0); + if (pid == 0) { + struct sock_filter filter[] = { + BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), + }; + struct sock_fprog prog = { + .len = (unsigned short)ARRAY_SIZE(filter), + .filter = filter, + }; + + /* one with log, one without */ + ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, + SECCOMP_FILTER_FLAG_LOG, &prog)); + ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog)); + + ASSERT_EQ(0, close(pipefd[0])); + ASSERT_EQ(1, write(pipefd[1], "1", 1)); + ASSERT_EQ(0, close(pipefd[1])); + + while (1) + sleep(100); + } + + ASSERT_EQ(0, close(pipefd[1])); + ASSERT_EQ(1, read(pipefd[0], &buf, 1)); + + ASSERT_EQ(0, ptrace(PTRACE_ATTACH, pid)); + ASSERT_EQ(pid, waitpid(pid, NULL, 0)); + + md.filter_off = 0; + ASSERT_EQ(sizeof(md), ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md)); + EXPECT_EQ(md.flags, SECCOMP_FILTER_FLAG_LOG); + EXPECT_EQ(md.filter_off, 0); + + md.filter_off = 1; + ASSERT_EQ(sizeof(md), ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md)); + EXPECT_EQ(md.flags, 0); + EXPECT_EQ(md.filter_off, 1); + + ASSERT_EQ(0, kill(pid, SIGKILL)); +} + /* * TODO: * - add microbenchmarks |