diff options
Diffstat (limited to 'fs/overlayfs')
-rw-r--r-- | fs/overlayfs/dir.c | 22 | ||||
-rw-r--r-- | fs/overlayfs/inode.c | 32 | ||||
-rw-r--r-- | fs/overlayfs/namei.c | 41 | ||||
-rw-r--r-- | fs/overlayfs/overlayfs.h | 10 | ||||
-rw-r--r-- | fs/overlayfs/readdir.c | 5 | ||||
-rw-r--r-- | fs/overlayfs/super.c | 13 | ||||
-rw-r--r-- | fs/overlayfs/util.c | 7 |
7 files changed, 88 insertions, 42 deletions
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index 641d9ee97f91..48b70e6490f3 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -481,17 +481,30 @@ out_cleanup: } static int ovl_create_or_link(struct dentry *dentry, struct inode *inode, - struct cattr *attr, struct dentry *hardlink) + struct cattr *attr, struct dentry *hardlink, + bool origin) { int err; const struct cred *old_cred; struct cred *override_cred; + struct dentry *parent = dentry->d_parent; - err = ovl_copy_up(dentry->d_parent); + err = ovl_copy_up(parent); if (err) return err; old_cred = ovl_override_creds(dentry->d_sb); + + /* + * When linking a file with copy up origin into a new parent, mark the + * new parent dir "impure". + */ + if (origin) { + err = ovl_set_impure(parent, ovl_dentry_upper(parent)); + if (err) + goto out_revert_creds; + } + err = -ENOMEM; override_cred = prepare_creds(); if (override_cred) { @@ -550,7 +563,7 @@ static int ovl_create_object(struct dentry *dentry, int mode, dev_t rdev, inode_init_owner(inode, dentry->d_parent->d_inode, mode); attr.mode = inode->i_mode; - err = ovl_create_or_link(dentry, inode, &attr, NULL); + err = ovl_create_or_link(dentry, inode, &attr, NULL, false); if (err) iput(inode); @@ -609,7 +622,8 @@ static int ovl_link(struct dentry *old, struct inode *newdir, inode = d_inode(old); ihold(inode); - err = ovl_create_or_link(new, inode, NULL, ovl_dentry_upper(old)); + err = ovl_create_or_link(new, inode, NULL, ovl_dentry_upper(old), + ovl_type_origin(old)); if (err) iput(inode); diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 69f4fc26ee39..5bc71642b226 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -202,37 +202,38 @@ bool ovl_is_private_xattr(const char *name) sizeof(OVL_XATTR_PREFIX) - 1) == 0; } -int ovl_xattr_set(struct dentry *dentry, const char *name, const void *value, - size_t size, int flags) +int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name, + const void *value, size_t size, int flags) { int err; - struct path realpath; - enum ovl_path_type type = ovl_path_real(dentry, &realpath); + struct dentry *upperdentry = ovl_i_dentry_upper(inode); + struct dentry *realdentry = upperdentry ?: ovl_dentry_lower(dentry); const struct cred *old_cred; err = ovl_want_write(dentry); if (err) goto out; - if (!value && !OVL_TYPE_UPPER(type)) { - err = vfs_getxattr(realpath.dentry, name, NULL, 0); + if (!value && !upperdentry) { + err = vfs_getxattr(realdentry, name, NULL, 0); if (err < 0) goto out_drop_write; } - err = ovl_copy_up(dentry); - if (err) - goto out_drop_write; + if (!upperdentry) { + err = ovl_copy_up(dentry); + if (err) + goto out_drop_write; - if (!OVL_TYPE_UPPER(type)) - ovl_path_upper(dentry, &realpath); + realdentry = ovl_dentry_upper(dentry); + } old_cred = ovl_override_creds(dentry->d_sb); if (value) - err = vfs_setxattr(realpath.dentry, name, value, size, flags); + err = vfs_setxattr(realdentry, name, value, size, flags); else { WARN_ON(flags != XATTR_REPLACE); - err = vfs_removexattr(realpath.dentry, name); + err = vfs_removexattr(realdentry, name); } revert_creds(old_cred); @@ -242,12 +243,13 @@ out: return err; } -int ovl_xattr_get(struct dentry *dentry, const char *name, +int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name, void *value, size_t size) { - struct dentry *realdentry = ovl_dentry_real(dentry); ssize_t res; const struct cred *old_cred; + struct dentry *realdentry = + ovl_i_dentry_upper(inode) ?: ovl_dentry_lower(dentry); old_cred = ovl_override_creds(dentry->d_sb); res = vfs_getxattr(realdentry, name, value, size); diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c index 9bc0e580a5b3..8aef2b304b2d 100644 --- a/fs/overlayfs/namei.c +++ b/fs/overlayfs/namei.c @@ -397,8 +397,19 @@ int ovl_verify_index(struct dentry *index, struct path *lowerstack, if (!d_inode(index)) return 0; - err = -EISDIR; - if (d_is_dir(index)) + /* + * Directory index entries are going to be used for looking up + * redirected upper dirs by lower dir fh when decoding an overlay + * file handle of a merge dir. Whiteout index entries are going to be + * used as an indication that an exported overlay file handle should + * be treated as stale (i.e. after unlink of the overlay inode). + * We don't know the verification rules for directory and whiteout + * index entries, because they have not been implemented yet, so return + * EROFS if those entries are found to avoid corrupting an index that + * was created by a newer kernel. + */ + err = -EROFS; + if (d_is_dir(index) || ovl_is_whiteout(index)) goto fail; err = -EINVAL; @@ -436,8 +447,8 @@ out: return err; fail: - pr_warn_ratelimited("overlayfs: failed to verify index (%pd2, err=%i)\n", - index, err); + pr_warn_ratelimited("overlayfs: failed to verify index (%pd2, ftype=%x, err=%i)\n", + index, d_inode(index)->i_mode & S_IFMT, err); goto out; } @@ -502,6 +513,7 @@ static struct dentry *ovl_lookup_index(struct dentry *dentry, goto out; } + inode = d_inode(index); if (d_is_negative(index)) { if (upper && d_inode(origin)->i_nlink > 1) { pr_warn_ratelimited("overlayfs: hard link with origin but no index (ino=%lu).\n", @@ -511,11 +523,22 @@ static struct dentry *ovl_lookup_index(struct dentry *dentry, dput(index); index = NULL; - } else if (upper && d_inode(index) != d_inode(upper)) { - inode = d_inode(index); - pr_warn_ratelimited("overlayfs: wrong index found (index ino: %lu, upper ino: %lu).\n", - d_inode(index)->i_ino, - d_inode(upper)->i_ino); + } else if (upper && d_inode(upper) != inode) { + pr_warn_ratelimited("overlayfs: wrong index found (index=%pd2, ino=%lu, upper ino=%lu).\n", + index, inode->i_ino, d_inode(upper)->i_ino); + goto fail; + } else if (ovl_dentry_weird(index) || ovl_is_whiteout(index) || + ((inode->i_mode ^ d_inode(origin)->i_mode) & S_IFMT)) { + /* + * Index should always be of the same file type as origin + * except for the case of a whiteout index. A whiteout + * index should only exist if all lower aliases have been + * unlinked, which means that finding a lower origin on lookup + * whose index is a whiteout should be treated as an error. + */ + pr_warn_ratelimited("overlayfs: bad index found (index=%pd2, ftype=%x, origin ftype=%x).\n", + index, d_inode(index)->i_mode & S_IFMT, + d_inode(origin)->i_mode & S_IFMT); goto fail; } diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 60d26605e039..e927a62c97ae 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -47,7 +47,8 @@ enum ovl_flag { /* Is the real inode encoded in fid an upper inode? */ #define OVL_FH_FLAG_PATH_UPPER (1 << 2) -#define OVL_FH_FLAG_ALL (OVL_FH_FLAG_BIG_ENDIAN | OVL_FH_FLAG_ANY_ENDIAN) +#define OVL_FH_FLAG_ALL (OVL_FH_FLAG_BIG_ENDIAN | OVL_FH_FLAG_ANY_ENDIAN | \ + OVL_FH_FLAG_PATH_UPPER) #if defined(__LITTLE_ENDIAN) #define OVL_FH_FLAG_CPU_ENDIAN 0 @@ -199,6 +200,7 @@ enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path); struct dentry *ovl_dentry_upper(struct dentry *dentry); struct dentry *ovl_dentry_lower(struct dentry *dentry); struct dentry *ovl_dentry_real(struct dentry *dentry); +struct dentry *ovl_i_dentry_upper(struct inode *inode); struct inode *ovl_inode_upper(struct inode *inode); struct inode *ovl_inode_lower(struct inode *inode); struct inode *ovl_inode_real(struct inode *inode); @@ -270,9 +272,9 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr); int ovl_getattr(const struct path *path, struct kstat *stat, u32 request_mask, unsigned int flags); int ovl_permission(struct inode *inode, int mask); -int ovl_xattr_set(struct dentry *dentry, const char *name, const void *value, - size_t size, int flags); -int ovl_xattr_get(struct dentry *dentry, const char *name, +int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name, + const void *value, size_t size, int flags); +int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name, void *value, size_t size); ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size); struct posix_acl *ovl_get_acl(struct inode *inode, int type); diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c index 0298463cf9c3..3d424a51cabb 100644 --- a/fs/overlayfs/readdir.c +++ b/fs/overlayfs/readdir.c @@ -703,7 +703,10 @@ int ovl_indexdir_cleanup(struct dentry *dentry, struct vfsmount *mnt, err = PTR_ERR(index); break; } - if (ovl_verify_index(index, lowerstack, numlower)) { + err = ovl_verify_index(index, lowerstack, numlower); + if (err) { + if (err == -EROFS) + break; err = ovl_cleanup(dir, index); if (err) break; diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 44dc2d6ffe0f..d86e89f97201 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -692,7 +692,7 @@ ovl_posix_acl_xattr_get(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size) { - return ovl_xattr_get(dentry, handler->name, buffer, size); + return ovl_xattr_get(dentry, inode, handler->name, buffer, size); } static int __maybe_unused @@ -742,7 +742,7 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler, return err; } - err = ovl_xattr_set(dentry, handler->name, value, size, flags); + err = ovl_xattr_set(dentry, inode, handler->name, value, size, flags); if (!err) ovl_copyattr(ovl_inode_real(inode), inode); @@ -772,7 +772,7 @@ static int ovl_other_xattr_get(const struct xattr_handler *handler, struct dentry *dentry, struct inode *inode, const char *name, void *buffer, size_t size) { - return ovl_xattr_get(dentry, name, buffer, size); + return ovl_xattr_get(dentry, inode, name, buffer, size); } static int ovl_other_xattr_set(const struct xattr_handler *handler, @@ -780,7 +780,7 @@ static int ovl_other_xattr_set(const struct xattr_handler *handler, const char *name, const void *value, size_t size, int flags) { - return ovl_xattr_set(dentry, name, value, size, flags); + return ovl_xattr_set(dentry, inode, name, value, size, flags); } static const struct xattr_handler __maybe_unused @@ -1058,10 +1058,6 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) ufs->indexdir = ovl_workdir_create(sb, ufs, workpath.dentry, OVL_INDEXDIR_NAME, true); - err = PTR_ERR(ufs->indexdir); - if (IS_ERR(ufs->indexdir)) - goto out_put_lower_mnt; - if (ufs->indexdir) { /* Verify upper root is index dir origin */ err = ovl_verify_origin(ufs->indexdir, ufs->upper_mnt, @@ -1090,6 +1086,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) else sb->s_d_op = &ovl_dentry_operations; + err = -ENOMEM; ufs->creator_cred = cred = prepare_creds(); if (!cred) goto out_put_indexdir; diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index c492ba75c659..f46ad75dc96a 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -157,9 +157,14 @@ struct dentry *ovl_dentry_real(struct dentry *dentry) return ovl_dentry_upper(dentry) ?: ovl_dentry_lower(dentry); } +struct dentry *ovl_i_dentry_upper(struct inode *inode) +{ + return ovl_upperdentry_dereference(OVL_I(inode)); +} + struct inode *ovl_inode_upper(struct inode *inode) { - struct dentry *upperdentry = ovl_upperdentry_dereference(OVL_I(inode)); + struct dentry *upperdentry = ovl_i_dentry_upper(inode); return upperdentry ? d_inode(upperdentry) : NULL; } |