diff options
Diffstat (limited to 'fs/orangefs/file.c')
| -rw-r--r-- | fs/orangefs/file.c | 39 |
1 files changed, 37 insertions, 2 deletions
diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c index a5612abc0936..c740159d9ad1 100644 --- a/fs/orangefs/file.c +++ b/fs/orangefs/file.c @@ -46,8 +46,9 @@ static int flush_racache(struct inode *inode) * Post and wait for the I/O upcall to finish */ ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inode, - loff_t *offset, struct iov_iter *iter, size_t total_size, - loff_t readahead_size, struct orangefs_write_range *wr, int *index_return) + loff_t *offset, struct iov_iter *iter, size_t total_size, + loff_t readahead_size, struct orangefs_write_range *wr, + int *index_return, struct file *file) { struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode); struct orangefs_khandle *handle = &orangefs_inode->refn.khandle; @@ -55,6 +56,8 @@ ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inode, int buffer_index; ssize_t ret; size_t copy_amount; + int open_for_read; + int open_for_write; new_op = op_alloc(ORANGEFS_VFS_OP_FILE_IO); if (!new_op) @@ -90,6 +93,38 @@ populate_shared_memory: new_op->upcall.uid = from_kuid(&init_user_ns, wr->uid); new_op->upcall.gid = from_kgid(&init_user_ns, wr->gid); } + /* + * Orangefs has no open, and orangefs checks file permissions + * on each file access. Posix requires that file permissions + * be checked on open and nowhere else. Orangefs-through-the-kernel + * needs to seem posix compliant. + * + * The VFS opens files, even if the filesystem provides no + * method. We can see if a file was successfully opened for + * read and or for write by looking at file->f_mode. + * + * When writes are flowing from the page cache, file is no + * longer available. We can trust the VFS to have checked + * file->f_mode before writing to the page cache. + * + * The mode of a file might change between when it is opened + * and IO commences, or it might be created with an arbitrary mode. + * + * We'll make sure we don't hit EACCES during the IO stage by + * using UID 0. Some of the time we have access without changing + * to UID 0 - how to check? + */ + if (file) { + open_for_write = file->f_mode & FMODE_WRITE; + open_for_read = file->f_mode & FMODE_READ; + } else { + open_for_write = 1; + open_for_read = 0; /* not relevant? */ + } + if ((type == ORANGEFS_IO_WRITE) && open_for_write) + new_op->upcall.uid = 0; + if ((type == ORANGEFS_IO_READ) && open_for_read) + new_op->upcall.uid = 0; gossip_debug(GOSSIP_FILE_DEBUG, "%s(%pU): offset: %llu total_size: %zd\n", |