client: implement support for O_PATH on Linux.

Signed-off-by: Radoslaw Zarzynski <rzarzynski@mirantis.com>

diff --git a/src/client/Client.cc b/src/client/Client.cc
index 8d5e192ba7cab5ac9a5b5d27fbd0272913703b4e..adf87a0b9791ff9e9db49d2801ef95d8401a73db 100644 (file)
--- a/src/client/Client.cc
+++ b/src/client/Client.cc
@@ -5587,6 +5587,10 @@ int Client::fchmod(int fd, mode_t mode)
   Fh *f = get_filehandle(fd);
   if (!f)
     return -EBADF;
+#if defined(__linux__)
+  if (f->flags & O_PATH)
+    return -EBADF;
+#endif
   struct stat attr;
   attr.st_mode = mode;
   return _setattr(f->inode, &attr, CEPH_SETATTR_MODE);
@@ -5640,6 +5644,10 @@ int Client::fchown(int fd, int uid, int gid)
   Fh *f = get_filehandle(fd);
   if (!f)
     return -EBADF;
+#if defined(__linux__)
+  if (f->flags & O_PATH)
+    return -EBADF;
+#endif
   struct stat attr;
   attr.st_uid = uid;
   attr.st_gid = gid;
@@ -6375,6 +6383,14 @@ int Client::open(const char *relpath, int flags, mode_t mode, int stripe_unit,
 
   Fh *fh = NULL;
 
+#if defined(__linux__)
+  /* When the O_PATH is being specified, others flags than O_DIRECTORY
+   * and O_NOFOLLOW are ignored. Please refer do_entry_open() function
+   * in kernel (fs/open.c). */
+  if (flags & O_PATH)
+    flags &= O_DIRECTORY | O_NOFOLLOW | O_PATH;
+#endif
+
   filepath path(relpath);
   Inode *in;
   bool created = false;
@@ -6385,7 +6401,11 @@ int Client::open(const char *relpath, int flags, mode_t mode, int stripe_unit,
   if (r == 0 && (flags & O_CREAT) && (flags & O_EXCL))
     return -EEXIST;
 
+#if defined(__linux__)
+  if (r == 0 && in->is_symlink() && (flags & O_NOFOLLOW) && !(flags & O_PATH))
+#else
   if (r == 0 && in->is_symlink() && (flags & O_NOFOLLOW))
+#endif
     return -ELOOP;
 
   if (r == -ENOENT && (flags & O_CREAT)) {
@@ -6700,6 +6720,10 @@ loff_t Client::lseek(int fd, loff_t offset, int whence)
   Fh *f = get_filehandle(fd);
   if (!f)
     return -EBADF;
+#if defined(__linux__)
+  if (f->flags & O_PATH)
+    return -EBADF;
+#endif
   return _lseek(f, offset, whence);
 }
 
@@ -6819,6 +6843,10 @@ int Client::read(int fd, char *buf, loff_t size, loff_t offset)
   Fh *f = get_filehandle(fd);
   if (!f)
     return -EBADF;
+#if defined(__linux__)
+  if (f->flags & O_PATH)
+    return -EBADF;
+#endif
   bufferlist bl;
   int r = _read(f, offset, size, &bl);
   ldout(cct, 3) << "read(" << fd << ", " << (void*)buf << ", " << size << ", " << offset << ") = " << r << dendl;
@@ -7140,6 +7168,10 @@ int Client::write(int fd, const char *buf, loff_t size, loff_t offset)
   Fh *fh = get_filehandle(fd);
   if (!fh)
     return -EBADF;
+#if defined(__linux__)
+  if (fh->flags & O_PATH)
+    return -EBADF;
+#endif
   int r = _write(fh, offset, size, buf);
   ldout(cct, 3) << "write(" << fd << ", \"...\", " << size << ", " << offset << ") = " << r << dendl;
   return r;
@@ -7385,6 +7417,10 @@ int Client::ftruncate(int fd, loff_t length)
   Fh *f = get_filehandle(fd);
   if (!f)
     return -EBADF;
+#if defined(__linux__)
+  if (f->flags & O_PATH)
+    return -EBADF;
+#endif
   struct stat attr;
   attr.st_size = length;
   return _setattr(f->inode, &attr, CEPH_SETATTR_SIZE);
@@ -7400,6 +7436,10 @@ int Client::fsync(int fd, bool syncdataonly)
   Fh *f = get_filehandle(fd);
   if (!f)
     return -EBADF;
+#if defined(__linux__)
+  if (f->flags & O_PATH)
+    return -EBADF;
+#endif
   int r = _fsync(f, syncdataonly);
   ldout(cct, 3) << "fsync(" << fd << ", " << syncdataonly << ") = " << r << dendl;
   return r;
@@ -9984,6 +10024,10 @@ int Client::fallocate(int fd, int mode, loff_t offset, loff_t length)
   Fh *fh = get_filehandle(fd);
   if (!fh)
     return -EBADF;
+#if defined(__linux__)
+  if (fh->flags & O_PATH)
+    return -EBADF;
+#endif
   return _fallocate(fh, mode, offset, length);
 }
 

diff --git a/src/test/libcephfs/test.cc b/src/test/libcephfs/test.cc
index 00cd36c080e29ea43f575016be3866f71396bd1e..a607a1bd8270a9628719b87c84962d161bd06446 100644 (file)
--- a/src/test/libcephfs/test.cc
+++ b/src/test/libcephfs/test.cc
@@ -22,6 +22,10 @@
 #include <dirent.h>
 #include <sys/xattr.h>
 
+#ifdef __linux__
+#include <limits.h>
+#endif
+
 TEST(LibCephFS, OpenEmptyComponent) {
 
   pid_t mypid = getpid();
@@ -650,8 +654,53 @@ TEST(LibCephFS, Fchown) {
 
   fd = ceph_open(cmount, test_file, O_RDWR, 0);
   ASSERT_EQ(fd, -EACCES);
+
+  ceph_shutdown(cmount);
+}
+
+#ifdef __linux__
+TEST(LibCephFS, FlagO_PATH) {
+  struct ceph_mount_info *cmount;
+
+  ASSERT_EQ(0, ceph_create(&cmount, NULL));
+  ASSERT_EQ(0, ceph_conf_parse_env(cmount, NULL));
+  ASSERT_EQ(0, ceph_conf_read_file(cmount, NULL));
+  ASSERT_EQ(0, ceph_mount(cmount, NULL));
+
+  char test_file[PATH_MAX];
+  sprintf(test_file, "test_oflag_%d", getpid());
+
+  int fd = ceph_open(cmount, test_file, O_CREAT|O_RDWR|O_PATH, 0666);
+  ASSERT_EQ(-ENOENT, fd);
+
+  fd = ceph_open(cmount, test_file, O_CREAT|O_RDWR, 0666);
+  ASSERT_GT(fd, 0);
+  ASSERT_EQ(0, ceph_close(cmount, fd));
+
+  // ok, the file has been created. perform real checks now
+  fd = ceph_open(cmount, test_file, O_CREAT|O_RDWR|O_PATH, 0666);
+  ASSERT_GT(fd, 0);
+
+  char buf[128];
+  ASSERT_EQ(-EBADF, ceph_read(cmount, fd, buf, sizeof(buf), 0));
+  ASSERT_EQ(-EBADF, ceph_write(cmount, fd, buf, sizeof(buf), 0));
+
+  // set perms to readable and writeable only by owner
+  ASSERT_EQ(-EBADF, ceph_fchmod(cmount, fd, 0600));
+
+  // change ownership to nobody -- we assume nobody exists and id is always 65534
+  ASSERT_EQ(-EBADF, ceph_fchown(cmount, fd, 65534, 65534));
+
+  // try to sync
+  ASSERT_EQ(-EBADF, ceph_fsync(cmount, fd, false));
+
+  struct stat sb;
+  ASSERT_EQ(0, ceph_fstat(cmount, fd, &sb));
+
+  ASSERT_EQ(0, ceph_close(cmount, fd));
   ceph_shutdown(cmount);
 }
+#endif /* __linux */
 
 TEST(LibCephFS, Symlinks) {
   struct ceph_mount_info *cmount;