o Introduce extattr_{delete,get,set}_fd() to allow extended attribute

  operations on file descriptors, which complement the existing set of
  calls, extattr_{delete,get,set}_file() which act on paths.  In doing
  so, restructure the system call implementation such that the two sets
  of functions share most of the relevant code, rather than duplicating
  it.  This pushes the vnode locking into the shared code, but keeps
  the copying in of some arguments in the system call code.  Allowing
  access via file descriptors reduces the opportunity for race
  conditions when managing extended attributes.

Obtained from:	TrustedBSD Project

1 files changed, 8 insertions, 0 deletions

diff --git a/sys/kern/syscalls.master b/sys/kern/syscalls.master
index 4130ff6..aec2ea6 100644
--- a/sys/kern/syscalls.master
+++ b/sys/kern/syscalls.master
@@ -533,3 +533,11 @@
 368	STD	BSD	{ int __cap_set_fd(int fd, struct cap *cap_p); }
 369	STD	BSD	{ int __cap_set_file(const char *path_p, struct cap *cap_p); }
 370	NODEF	NOHIDE	lkmressys lkmressys nosys_args int
+371	STD	BSD	{ int extattr_set_fd(int fd, int attrnamespace, \
+			    const char *attrname, struct iovec *iovp, \
+			    int iovcnt); }
+372	STD	BSD	{ int extattr_get_fd(int fd, int attrnamespace, \
+			    const char *attrname, struct iovec *iovp, \
+			    int iovcnt); }
+373	STD	BSD	{ int extattr_delete_fd(int fd, int attrnamespace, \
+			    const char *attrname); }