summaryrefslogtreecommitdiff
path: root/fs/udf/inode.c
diff options
context:
space:
mode:
authorSteven J. Magnani <steve.magnani@digidescorp.com>2019-08-27 07:13:59 -0500
committerJan Kara <jack@suse.cz>2019-08-27 15:38:46 +0200
commitc3367a1b47d590f97109cd4b5189e750fb26c0f1 (patch)
tree8f29eb87d3375f3ff048b3384bef9692bde86367 /fs/udf/inode.c
parent8cbd9af9d208b1f015cf8a4645602f0a007270a8 (diff)
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>
Diffstat (limited to 'fs/udf/inode.c')
-rw-r--r--fs/udf/inode.c31
1 files changed, 27 insertions, 4 deletions
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 54eee39f2698..ea80036d7897 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -45,6 +45,13 @@
#define EXTENT_MERGE_SIZE 5
+#define FE_MAPPED_PERMS (FE_PERM_U_READ | FE_PERM_U_WRITE | FE_PERM_U_EXEC | \
+ FE_PERM_G_READ | FE_PERM_G_WRITE | FE_PERM_G_EXEC | \
+ FE_PERM_O_READ | FE_PERM_O_WRITE | FE_PERM_O_EXEC)
+
+#define FE_DELETE_PERMS (FE_PERM_U_DELETE | FE_PERM_G_DELETE | \
+ FE_PERM_O_DELETE)
+
static umode_t udf_convert_permissions(struct fileEntry *);
static int udf_update_inode(struct inode *, int);
static int udf_sync_inode(struct inode *inode);
@@ -1458,6 +1465,8 @@ reread:
else
inode->i_mode = udf_convert_permissions(fe);
inode->i_mode &= ~sbi->s_umask;
+ iinfo->i_extraPerms = le32_to_cpu(fe->permissions) & ~FE_MAPPED_PERMS;
+
read_unlock(&sbi->s_cred_lock);
link_count = le16_to_cpu(fe->fileLinkCount);
@@ -1631,6 +1640,23 @@ static umode_t udf_convert_permissions(struct fileEntry *fe)
return mode;
}
+void udf_update_extra_perms(struct inode *inode, umode_t mode)
+{
+ struct udf_inode_info *iinfo = UDF_I(inode);
+
+ /*
+ * UDF 2.01 sec. 3.3.3.3 Note 2:
+ * In Unix, delete permission tracks write
+ */
+ iinfo->i_extraPerms &= ~FE_DELETE_PERMS;
+ if (mode & 0200)
+ iinfo->i_extraPerms |= FE_PERM_U_DELETE;
+ if (mode & 0020)
+ iinfo->i_extraPerms |= FE_PERM_G_DELETE;
+ if (mode & 0002)
+ iinfo->i_extraPerms |= FE_PERM_O_DELETE;
+}
+
int udf_write_inode(struct inode *inode, struct writeback_control *wbc)
{
return udf_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
@@ -1703,10 +1729,7 @@ static int udf_update_inode(struct inode *inode, int do_sync)
((inode->i_mode & 0070) << 2) |
((inode->i_mode & 0700) << 4);
- udfperms |= (le32_to_cpu(fe->permissions) &
- (FE_PERM_O_DELETE | FE_PERM_O_CHATTR |
- FE_PERM_G_DELETE | FE_PERM_G_CHATTR |
- FE_PERM_U_DELETE | FE_PERM_U_CHATTR));
+ udfperms |= iinfo->i_extraPerms;
fe->permissions = cpu_to_le32(udfperms);
if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)