[PATCH 2/2] ptrace: add ability to attach a file descriptor to another task

[Andrew Vagin]

Signed-off-by: Andrew Vagin <avagin@xxxxxxxxxx>
---
 include/linux/ptrace.h |    1 +
 kernel/ptrace.c        |   27 +++++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 0 deletions(-)

diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index 800f113..8439ce9 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -50,6 +50,7 @@
 #define PTRACE_SEIZE		0x4206
 #define PTRACE_INTERRUPT	0x4207
 #define PTRACE_LISTEN		0x4208
+#define PTRACE_DUPFD		0x4209
 
 /* flags in @data for PTRACE_SEIZE */
 #define PTRACE_SEIZE_DEVEL	0x80000000 /* temp flag for development */
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 24d0447..a646d01 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -24,6 +24,7 @@
 #include <linux/regset.h>
 #include <linux/hw_breakpoint.h>
 #include <linux/cn_proc.h>
+#include <linux/file.h>
 
 
 static int ptrace_trapping_sleep_fn(void *flags)
@@ -826,6 +827,32 @@ int ptrace_request(struct task_struct *child, long request,
 		break;
 	}
 #endif
+	case PTRACE_DUPFD:
+	{
+		struct file *file = fget_raw(data);
+		ret = -EBADF;
+
+		if (!file)
+			break;
+
+		task_lock(child);
+		if (!child->files)
+			goto out_getfd;
+
+		ret = alloc_task_fd(child, 0, 0);
+		if (ret < 0) {
+			fput(file);
+			goto out_getfd;
+		}
+
+		fd_task_install(child, ret, file);
+
+out_getfd:
+		task_unlock(child);
+
+		break;
+	}
+
 	default:
 		break;
 	}
-- 
1.7.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/