linux-brain/fs/udf/udf_i.h
Steven J. Magnani c3367a1b47 udf: augment UDF permissions on new inodes
Windows presents files created within Linux as read-only, even when
permissions in Linux indicate the file should be writable.

UDF defines a slightly different set of basic file permissions than Linux.
Specifically, UDF has "delete" and "change attribute" permissions for each
access class (user/group/other). Linux has no equivalents for these.

When the Linux UDF driver creates a file (or directory), no UDF delete or
change attribute permissions are granted. The lack of delete permission
appears to cause Windows to mark an item read-only when its permissions
otherwise indicate that it should be read-write.

Fix this by having UDF delete permissions track Linux write permissions.
Also grant UDF change attribute permission to the owner when creating a
new inode.

Reported by: Ty Young
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Link: https://lore.kernel.org/r/20190827121359.9954-1-steve@digidescorp.com
Signed-off-by: Jan Kara <jack@suse.cz>
2019-08-27 15:38:46 +02:00

68 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _UDF_I_H
#define _UDF_I_H
struct extent_position {
struct buffer_head *bh;
uint32_t offset;
struct kernel_lb_addr block;
};
struct udf_ext_cache {
/* Extent position */
struct extent_position epos;
/* Start logical offset in bytes */
loff_t lstart;
};
/*
* The i_data_sem and i_mutex serve for protection of allocation information
* of a regular files and symlinks. This includes all extents belonging to
* the file/symlink, a fact whether data are in-inode or in external data
* blocks, preallocation, goal block information... When extents are read,
* i_mutex or i_data_sem must be held (for reading is enough in case of
* i_data_sem). When extents are changed, i_data_sem must be held for writing
* and also i_mutex must be held.
*
* For directories i_mutex is used for all the necessary protection.
*/
struct udf_inode_info {
struct timespec64 i_crtime;
/* Physical address of inode */
struct kernel_lb_addr i_location;
__u64 i_unique;
__u32 i_lenEAttr;
__u32 i_lenAlloc;
__u64 i_lenExtents;
__u32 i_next_alloc_block;
__u32 i_next_alloc_goal;
__u32 i_checkpoint;
__u32 i_extraPerms;
unsigned i_alloc_type : 3;
unsigned i_efe : 1; /* extendedFileEntry */
unsigned i_use : 1; /* unallocSpaceEntry */
unsigned i_strat4096 : 1;
unsigned i_streamdir : 1;
unsigned reserved : 25;
union {
struct short_ad *i_sad;
struct long_ad *i_lad;
__u8 *i_data;
} i_ext;
struct kernel_lb_addr i_locStreamdir;
__u64 i_lenStreams;
struct rw_semaphore i_data_sem;
struct udf_ext_cache cached_extent;
/* Spinlock for protecting extent cache */
spinlock_t i_extent_cache_lock;
struct inode vfs_inode;
};
static inline struct udf_inode_info *UDF_I(struct inode *inode)
{
return container_of(inode, struct udf_inode_info, vfs_inode);
}
#endif /* _UDF_I_H) */