Mounting a local repository onto its own directory caused the FUSE
server to read its own backend files through the mount it had just
created, deadlocking the kernel. `umount` then reported "Device or
resource busy" and recovery required a reboot that took several
minutes. The same shape occurs when the mountpoint is nested inside
the repository directory, or when the repository directory is nested
inside the mountpoint.
The mount command now resolves both paths via filepath.Abs and
filepath.EvalSymlinks and refuses with a fatal error if either path
equals or contains the other. The check runs before the repository
lock is acquired so an overlap fails fast. Only the local backend is
checked; remote backends cannot shadow the mountpoint directory.
* mount: check for more requisite mountpoint conditions
In order to be able to mount a repository over a mountpoint target
directory via FUSE, that target directory needs to be both writeable and
executable for the UID performing the mount.
Without this patch, `restic mount` only checks for the target pathname's
existence, which can lead to a lot of data transfer and/or computation
for large repos to be performed before eventually croaking with a fatal
"fusermount: failed to chdir to mountpoint: Permission denied" (or
similar) error.
FUSE does allow for mounting over a target path that refers to a regular
(writeable) file, but the result is not accessible via chdir(), so we
prevent that as well, and accept only directory inodes as the intended
target mountpoint path.
* Don't use snake_case identifiers
* Add changelog entry
* tweak changelog summary
---------
Co-authored-by: Michael Eischer <michael.eischer@fau.de>
cmd/restic/cmd_rewrite.go:
introduction of include filters for this command:
- add include filters, add error checking code
- add new parameter 'keepEmptyDirectoryFunc' to 'walker.NewSnapshotSizeRewriter()',
so empty directories have to be kept to keep the directory structure intact
- add parameter 'keepEmptySnapshot' to 'filterAndReplaceSnapshot()' to keep snapshots
intact when nothing is to be included
- introduce helper function 'gatherIncludeFilters()' and 'gatherExcludeFilters()' to
keep code flow clean
cmd/restic/cmd_rewrite_integration_test.go:
add several new tests around the 'include' functionality
internal/filter/include.go:
this is where is include filter is defined
internal/walker/rewriter.go:
- struct RewriteOpts gains field 'KeepEmtpyDirectory', which is a 'NodeKeepEmptyDirectoryFunc()'
which defaults to nil, so that al subdirectories are kept
- function 'NewSnapshotSizeRewriter()' gains the parameter 'keepEmptyDirecoryFilter' which
controls the management of empty subdirectories in case of include filters active
internal/data/tree.go:
gains a function Count() for checking the number if node elements in a newly built tree
internal/walker/rewriter_test.go:
function 'NewSnapshotSizeRewriter()' gets an additional parameter nil to keeps things happy
cmd/restic/cmd_repair_snapshots.go:
function 'filterAndReplaceSnapshot()' gets an additional parameter 'keepEmptySnapshot=nil'
doc/045_working_with_repos.rst:
gets to mention include filters
changelog/unreleased/issue-4278:
the usual announcement file
git rebase master -i produced this
restic rewrite include - keep linter happy
cmd/restic/cmd_rewrite_integration_test.go:
linter likes strings.Contain() better than my strings.Index() >= 0
Michael Eischer
Michael Eischer
Yaroslav Halchenko
Winfried Plappert
Srigovind Nayak
Paulo Saraiva
Matt
Johannes Truschnigg
Andreas Scherbaum
gunar