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| author | Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com> | 2018-10-30 15:06:17 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-10-31 08:54:13 -0700 |
| commit | 54640c7502e5ed41fbf4eedd499e85f9acc9698f (patch) | |
| tree | 0745ae35891531719808bf29bdcecf0bf8cf1119 /fs/hfs/extent.c | |
| parent | d92915c35bfaf763d78bf1d5ac7f183420e3bd99 (diff) | |
| download | linux-54640c7502e5ed41fbf4eedd499e85f9acc9698f.tar.bz2 | |
hfs: prevent btree data loss on ENOSPC
Inserting a new 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 or
extents.
Henceforth, check the available disk space before making any changes.
This still leaves the potential problem of corruption on ENOMEM.
There is no need to reserve space before deleting a catalog record, as we
do for hfsplus. This difference is because hfs index nodes have fixed
length keys.
Link: http://lkml.kernel.org/r/ab5fc8a7d5ffccfd5f27b1cf2cb4ceb6c110da74.1536269131.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/hfs/extent.c')
| -rw-r--r-- | fs/hfs/extent.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/hfs/extent.c b/fs/hfs/extent.c index 5d0182654580..0c638c612152 100644 --- a/fs/hfs/extent.c +++ b/fs/hfs/extent.c @@ -117,6 +117,10 @@ static int __hfs_ext_write_extent(struct inode *inode, struct hfs_find_data *fd) if (HFS_I(inode)->flags & HFS_FLG_EXT_NEW) { if (res != -ENOENT) return res; + /* Fail early and avoid ENOSPC during the btree operation */ + res = hfs_bmap_reserve(fd->tree, fd->tree->depth + 1); + if (res) + return res; hfs_brec_insert(fd, HFS_I(inode)->cached_extents, sizeof(hfs_extent_rec)); HFS_I(inode)->flags &= ~(HFS_FLG_EXT_DIRTY|HFS_FLG_EXT_NEW); } else { |