udf: Clean up handling of invalid uid/gid

Current code relies on the fact that invalid uid/gid as defined by UDF
2.60 3.3.3.1 and 3.3.3.2 coincides with invalid uid/gid as used by the
user namespaces implementation. Since this is only lucky coincidence,
clean this up to avoid future surprises in case user namespaces
implementation changes. Also this is more robust in presence of valid
(from UDF point of view) uids / gids which do not map into current user
namespace.

Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Kara 2018-02-22 10:28:52 +01:00
parent ecd10aa428
commit 0c9850f4d4
2 changed files with 15 additions and 8 deletions

View File

@ -1275,6 +1275,7 @@ static int udf_read_inode(struct inode *inode, bool hidden_inode)
unsigned int indirections = 0;
int bs = inode->i_sb->s_blocksize;
int ret = -EIO;
uint32_t uid, gid;
reread:
if (iloc->partitionReferenceNum >= sbi->s_partitions) {
@ -1400,15 +1401,19 @@ reread:
ret = -EIO;
read_lock(&sbi->s_cred_lock);
i_uid_write(inode, le32_to_cpu(fe->uid));
if (!uid_valid(inode->i_uid) ||
uid = le32_to_cpu(fe->uid);
if (uid == UDF_INVALID_ID ||
UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_SET))
inode->i_uid = UDF_SB(inode->i_sb)->s_uid;
inode->i_uid = sbi->s_uid;
else
i_uid_write(inode, uid);
i_gid_write(inode, le32_to_cpu(fe->gid));
if (!gid_valid(inode->i_gid) ||
gid = le32_to_cpu(fe->gid);
if (gid == UDF_INVALID_ID ||
UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
inode->i_gid = UDF_SB(inode->i_sb)->s_gid;
inode->i_gid = sbi->s_gid;
else
i_gid_write(inode, gid);
if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
sbi->s_fmode != UDF_INVALID_MODE)
@ -1653,12 +1658,12 @@ static int udf_update_inode(struct inode *inode, int do_sync)
}
if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
fe->uid = cpu_to_le32(-1);
fe->uid = cpu_to_le32(UDF_INVALID_ID);
else
fe->uid = cpu_to_le32(i_uid_read(inode));
if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_FORGET))
fe->gid = cpu_to_le32(-1);
fe->gid = cpu_to_le32(UDF_INVALID_ID);
else
fe->gid = cpu_to_le32(i_gid_read(inode));

View File

@ -48,6 +48,8 @@ extern __printf(3, 4) void _udf_warn(struct super_block *sb,
#define UDF_EXTENT_LENGTH_MASK 0x3FFFFFFF
#define UDF_EXTENT_FLAG_MASK 0xC0000000
#define UDF_INVALID_ID ((uint32_t)-1)
#define UDF_NAME_PAD 4
#define UDF_NAME_LEN 254
#define UDF_NAME_LEN_CS0 255