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| author | Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com> | 2018-10-31 01:06:14 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-10-31 18:54:13 +0300 |
| commit | d92915c35bfaf763d78bf1d5ac7f183420e3bd99 (patch) | |
| tree | 6c55bdd6cdbff28215f7a4df2c61ed31716ca09a /fs/hfsplus/catalog.c | |
| parent | ef75bcc5763d130451a99825f247d301088b790b (diff) | |
| download | linux-d92915c35bfaf763d78bf1d5ac7f183420e3bd99.tar.xz | |
hfsplus: prevent btree data loss on ENOSPC
Inserting or deleting a record in a btree may require splitting several of
its nodes. If we hit ENOSPC halfway through, the new nodes will be left
orphaned and their records will be lost. This could mean lost inodes,
extents or xattrs.
Henceforth, check the available disk space before making any changes.
This still leaves the potential problem of corruption on ENOMEM.
The patch can be tested with xfstests generic/027.
Link: http://lkml.kernel.org/r/4596eef22fbda137b4ffa0272d92f0da15364421.1536269129.git.ernesto.mnd.fernandez@gmail.com
Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/hfsplus/catalog.c')
| -rw-r--r-- | fs/hfsplus/catalog.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/fs/hfsplus/catalog.c b/fs/hfsplus/catalog.c index a196369ba779..35472cba750e 100644 --- a/fs/hfsplus/catalog.c +++ b/fs/hfsplus/catalog.c @@ -265,6 +265,14 @@ int hfsplus_create_cat(u32 cnid, struct inode *dir, if (err) return err; + /* + * Fail early and avoid ENOSPC during the btree operations. We may + * have to split the root node at most once. + */ + err = hfs_bmap_reserve(fd.tree, 2 * fd.tree->depth); + if (err) + goto err2; + hfsplus_cat_build_key_with_cnid(sb, fd.search_key, cnid); entry_size = hfsplus_fill_cat_thread(sb, &entry, S_ISDIR(inode->i_mode) ? @@ -333,6 +341,14 @@ int hfsplus_delete_cat(u32 cnid, struct inode *dir, const struct qstr *str) if (err) return err; + /* + * Fail early and avoid ENOSPC during the btree operations. We may + * have to split the root node at most once. + */ + err = hfs_bmap_reserve(fd.tree, 2 * (int)fd.tree->depth - 2); + if (err) + goto out; + if (!str) { int len; @@ -433,6 +449,14 @@ int hfsplus_rename_cat(u32 cnid, return err; dst_fd = src_fd; + /* + * Fail early and avoid ENOSPC during the btree operations. We may + * have to split the root node at most twice. + */ + err = hfs_bmap_reserve(src_fd.tree, 4 * (int)src_fd.tree->depth - 1); + if (err) + goto out; + /* find the old dir entry and read the data */ err = hfsplus_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name); |