udf: Protect default inode credentials by rwlock

Superblock carries credentials (uid, gid, etc.) which are used as default
values in __udf_read_inode() when media does not provide these. These
credentials can change during remount so we protect them by a rwlock so that
each inode gets a consistent set of credentials.

Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Kara 2010-10-20 22:17:28 +02:00
parent 949f4a7c08
commit c03cad241a
3 changed files with 14 additions and 7 deletions

View file

@ -1201,6 +1201,7 @@ static void udf_fill_inode(struct inode *inode, struct buffer_head *bh)
return;
}
read_lock(&sbi->s_cred_lock);
inode->i_uid = le32_to_cpu(fe->uid);
if (inode->i_uid == -1 ||
UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_IGNORE) ||
@ -1213,13 +1214,6 @@ static void udf_fill_inode(struct inode *inode, struct buffer_head *bh)
UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_GID_SET))
inode->i_gid = UDF_SB(inode->i_sb)->s_gid;
inode->i_nlink = le16_to_cpu(fe->fileLinkCount);
if (!inode->i_nlink)
inode->i_nlink = 1;
inode->i_size = le64_to_cpu(fe->informationLength);
iinfo->i_lenExtents = inode->i_size;
if (fe->icbTag.fileType != ICBTAG_FILE_TYPE_DIRECTORY &&
sbi->s_fmode != UDF_INVALID_MODE)
inode->i_mode = sbi->s_fmode;
@ -1229,6 +1223,14 @@ static void udf_fill_inode(struct inode *inode, struct buffer_head *bh)
else
inode->i_mode = udf_convert_permissions(fe);
inode->i_mode &= ~sbi->s_umask;
read_unlock(&sbi->s_cred_lock);
inode->i_nlink = le16_to_cpu(fe->fileLinkCount);
if (!inode->i_nlink)
inode->i_nlink = 1;
inode->i_size = le64_to_cpu(fe->informationLength);
iinfo->i_lenExtents = inode->i_size;
if (iinfo->i_efe == 0) {
inode->i_blocks = le64_to_cpu(fe->logicalBlocksRecorded) <<

View file

@ -568,12 +568,14 @@ static int udf_remount_fs(struct super_block *sb, int *flags, char *options)
return -EINVAL;
lock_kernel();
write_lock(&sbi->s_cred_lock);
sbi->s_flags = uopt.flags;
sbi->s_uid = uopt.uid;
sbi->s_gid = uopt.gid;
sbi->s_umask = uopt.umask;
sbi->s_fmode = uopt.fmode;
sbi->s_dmode = uopt.dmode;
write_unlock(&sbi->s_cred_lock);
if (sbi->s_lvid_bh) {
int write_rev = le16_to_cpu(udf_sb_lvidiu(sbi)->minUDFWriteRev);
@ -1960,6 +1962,7 @@ static int udf_fill_super(struct super_block *sb, void *options, int silent)
sbi->s_fmode = uopt.fmode;
sbi->s_dmode = uopt.dmode;
sbi->s_nls_map = uopt.nls_map;
rwlock_init(&sbi->s_cred_lock);
if (uopt.session == 0xFFFFFFFF)
sbi->s_session = udf_get_last_session(sb);

View file

@ -129,6 +129,8 @@ struct udf_sb_info {
uid_t s_uid;
mode_t s_fmode;
mode_t s_dmode;
/* Lock protecting consistency of above permission settings */
rwlock_t s_cred_lock;
/* Root Info */
struct timespec s_record_time;