With --links/-l, a symlink is served as a .rclonelink object whose
content is the target path. A Range request with a start offset beyond
the target length (e.g. "Range: bytes=99999999999-") reached
openTranslatedLink and sliced the target string at that offset, panicking
with "slice bounds out of range".
Clamp the offset to the target length so an out-of-range start reads
empty, matching how a real file read past EOF behaves.
With -l/--links the local backend faithfully recreates a source ".rclonelink" as
a real symlink at the destination. Directory metadata (chmod/chown/chtimes),
however, was applied with the raw following syscalls
os.Chmod/os.Chown/os.Chtimes rather than through the os.Root sandbox used for
content writes. A Directory is never a translatedLink, so when the destination
path already existed as a symlink planted by an untrusted source, the metadata
was applied through it to a target outside the backup destination.
Route directory metadata through os.Root when translating symlinks, so a planted
symlink can no longer redirect chmod/chown/chtimes out of the destination, while
legitimate in-tree directories are unaffected.
The concurrent walker created by walk() only stopped when the callback
returned an error or the whole tree had been listed. Cancelling the
context (for example via the rc job/stop endpoint for an async
operations/size or recursive operations/list call) was therefore
ignored: the checkers kept pulling list jobs from the channel and kept
listing the entire tree, burning CPU and making job cancellation
useless for every backend without a native ListR implementation.
Make every checker select on ctx.Done() so a cancelled walk shuts down
promptly through the existing quit/drain path and reports the context
error. Also check the context between directory read chunks in the
local backend so a single huge directory does not block cancellation.
When copying to the local backend with checksums enabled (the default),
rclone hashed the incoming data by wrapping the source reader in an
io.TeeReader. TeeReader has no WriteTo method, so io.Copy could not use
the source's fast path and fell back to its generic 32 KiB buffer loop.
The same wrapping also stopped the destination *os.File using
copy_file_range, since the source was no longer a raw fd.
This meant checksummed copies were written in 32 KiB chunks whereas
--ignore-checksum copies were written in much larger blocks (typically
1 MiB). On filesystems where small writes are expensive, such as FUSE
mounts like LucidLink, this made a big difference: copying a 100 MiB
file took 3203 x 32 KiB writes in 3.6s, and now takes 108 x ~1 MiB
writes in 0.47s.
The local backend built every OS path by joining the root with the source
name converted through the configured encoding, so the encoding was the only
thing keeping a name from turning into path syntax.
With an encoding which omits Dot (Slash, None, Raw) rclone's standard ".."
decodes back to a real "..", and with an encoding which omits BackSlash a name
like "..\file" becomes a native path on Windows. filepath.Join then resolved
those out of the destination the user chose, so a source object called
"../marker.txt" - an s3 key of "tenant/../marker.txt" listed with the remote
rooted at "tenant", say - created or overwrote a file outside it.
localPath now joins the name to the root and checks with filepath.Rel that the
result is still inside it. localPath is the only place the root is joined to a
name, so threading the error through newObject and newDirectory covers every
operation.
Default configurations were not affected, as encoder.OS includes Dot on all
platforms and BackSlash on Windows.
Fixes GHSA-7p4m-qxvv-g567
cleanRootPath used filepath.Abs which prepends the current directory,
but the resulting absolute path does not always refer to the same
directory as the original relative path - for example when the current
directory is shadowed by a mount or has been removed. This made
"rclone copy --links . ../dst" fail where "cp -ra . ../dst" succeeds.
rclone now cleans the path lexically on non-Windows platforms instead,
leaving relative roots relative so the OS resolves them against the live
working directory. Windows still makes the path absolute as required for
UNC long-path conversion.
With -l/--links rclone recreates a .rclonelink object as a symlink. A
malicious or compromised source could serve a symlink whose target points
outside the destination, plus a sibling object whose path traverses it, so
that rclone followed the planted symlink and wrote outside the destination
causing arbitrary file write.
When translating symlinks, rclone now performs all destination writes
(directory creation, file writes and symlink creation) through an os.Root
anchored at the destination. os.Root resolves every path component relative
to the destination's file descriptor and refuses any that escapes the root,
even under concurrent modification, so a planted symlink can never be
traversed out of the destination.
Symlinks are still reproduced verbatim - including ones whose target points
outside the destination - so backups remain faithful. Only writing
*through* such a link is refused. In-tree symlinks are unaffected.
Fixes CVE-2026-54572
Fixes GHSA-cf44-9pgv-m4xc
When applying the "mode" from --metadata the local backend cast the
source value straight to an os.FileMode, so a source that supplied a
mode with Go's setuid, setgid or sticky bits set would have those bits
applied to the freshly written file. As both the file content and its
metadata come from the source remote, a malicious source could plant a
setuid binary, and a victim running "rclone copy -M" as root against
an untrusted remote could end up with a root-owned setuid binary with
attacker-controlled content.
Rclone records "mode" in the unix st_mode layout where the special
bits live in different positions to Go's os.FileMode, so honest
sources never actually round-tripped these bits in the first place.
Apply only the permission bits by default, which closes this off and
is backwards compatible, and add the --local-metadata-restore-special-bits
lag to restore the previous behaviour for trusted sources such as
restoring a system backup made by rclone.
See: GHSA-945v-v9p3-v5xw
When enabled, an out-of-space error during a local write returns a
fatal error that aborts the run, instead of being retried.
Without this option, ENOSPC errors are treated as retryable and
rclone may spin through the retry loop many times on a full disk
before giving up. That is fine for transient network errors but
unhelpful when the disk is genuinely full and the operator wants
the run to fail loudly. Default is off so existing behaviour is
unchanged.
Implementation follows the pattern suggested in the issue: a defer
at the top of Update wraps the error with fserrors.FatalError when
the option is on and the error is disk-full. Detection covers both
file.ErrDiskFull from the preallocate path and syscall.ENOSPC from
io.Copy or Close, via a small helper that uses fserrors.IsErrNoSpace.
Remove the POSIX_FADV_DONTNEED and POSIX_FADV_SEQUENTIAL calls
from the local backend. The DONTNEED calls cause severe spinlock
contention on parallel file systems (and any system with many
concurrent transfers), because each call triggers per-page cache
teardown under a global lock.
Observed on a 256-core system running rclone with 64 parallel
transfers over Lustre: 69% of all CPU cycles were spent in
kernel spinlock contention from the fadvise path, with effective
throughput well below hardware capability.
The kernel's own page reclaim (kswapd) handles eviction more
efficiently from a single context. Since rclone does not always
read files sequentially (e.g. multipart uploads rewind and
re-read blocks), FADV_SEQUENTIAL was also not reliably correct.
This is consistent with the non-Linux behavior (which never
called fadvise) and with restic's decision to remove identical
code (restic/restic#670).
Fixes#7886
Give users a way to explicitly acknowledge that pipes, sockets and block
devices are to be ignored without warnings.
This follows the precedent set in commit 6152bab28 (local: add
--skip-links to suppress symlink warnings, 2017-07-21) for ignoring
warnings about symlinks.
Before this change, Rmdir (and other commands that rely on Rmdir) would fail
with "Access is denied" on Windows, if the directory had
FILE_ATTRIBUTE_READONLY. This could happen if, for example, an empty folder had
a custom icon added via Windows Explorer's interface (Properties => Customize =>
Change Icon...).
However, Microsoft docs indicate that "This attribute is not honored on
directories."
https://learn.microsoft.com/en-us/windows/win32/fileio/file-attribute-constants#file_attribute_readonly
Accordingly, this created an odd situation where such directories were removable
(by their owner) via File Explorer and the rd command, but not via rclone.
An upstream issue has been open since 2018, but has not yet resulted in a fix.
https://github.com/golang/go/issues/26295
This change gets around the issue by doing os.Chmod on the dir and then retrying
os.Remove. If the dir is not empty, this will still fail with "The directory is
not empty."
A bisync user confirmed that it fixed their issue in
https://forum.rclone.org/t/bisync-leaving-empty-directories-on-unc-path-1-or-local-filesystem-path-2-on-directory-renames/52456/4?u=nielash
It is likely also a fix for #8019, although @ncw is correct that Purge would be
a more efficient solution in that particular scenario.
Due to a change in Go which was enabled by the `go 1.22` in `go.mod`
rclone has stopped skipping junction points ("My Documents" in
particular) if `--skip-links` is set on Windows.
This is because the output from os.Lstat has changed and junction
points are no longer marked with os.ModeSymlink but with
os.ModeIrregular instead.
This fix now skips os.ModeIrregular objects if --skip-links is set on
Windows only.
Fixes#8561
See: https://github.com/golang/go/issues/73827
This commit modernizes Go usage. This was done with:
go run golang.org/x/tools/gopls/internal/analysis/modernize/cmd/modernize@latest -fix -test ./...
Then files needed to be `go fmt`ed and a few comments needed to be
restored.
The modernizations include replacing
- if/else conditional assignment by a call to the built-in min or max functions added in go1.21
- sort.Slice(x, func(i, j int) bool) { return s[i] < s[j] } by a call to slices.Sort(s), added in go1.21
- interface{} by the 'any' type added in go1.18
- append([]T(nil), s...) by slices.Clone(s) or slices.Concat(s), added in go1.21
- loop around an m[k]=v map update by a call to one of the Collect, Copy, Clone, or Insert functions from the maps package, added in go1.21
- []byte(fmt.Sprintf...) by fmt.Appendf(nil, ...), added in go1.19
- append(s[:i], s[i+1]...) by slices.Delete(s, i, i+1), added in go1.21
- a 3-clause for i := 0; i < n; i++ {} loop by for i := range n {}, added in go1.22
Before this change the --links flag when using the VFS override the
--links flag for the local backend which meant the local backend
needed explicit config to use links.
This fixes the problem by making the --links flag global and adding a
new --local-links flag and --vfs-links flags to control the features
individually if required.
This flag allows users to disable the reflink cloning feature and instead force
"deep" copies, for certain use cases where data redundancy is preferable. It is
functionally equivalent to using `--disable Copy` on local.
fix#7824
Statements like rclone copy <somewhere> . will spontaneously miss
if . expands to a path with a Full Width replacement character.
This is due to the incorrect order in which
relative paths and decoding were handled in the original implementation.
In this commit (2014 for v1.02) Purge was implemented for the local
backend:
1527e64ee7 local: Implement Purger interface
This appeared to be implemented just to make a Purge and doesn't
appear to do anything useful.
It is in fact significatly worse than the rclone fallback purge since
it doesn't operate in parallel or update stats.
This patch removes the Purge routine for a consequent speed up and
showing of stats.
See: https://forum.rclone.org/t/progress-flag-for-rclone-purge/44416
A consequence of this is that fs.Directory returned by the local
backend will now have a correct size in (rather than -1). Some tests
depended on this and have been fixed by this commit too.
Similar to
https://github.com/rclone/rclone/commit/acf1e2df84a350b7a86d7672d749dfb1ba090a44,
go1.21.4 appears to have broken sync.MoveDir on Windows because
filepath.VolumeName() returns `\\?` instead of `\\?\C:` in cleanRootPath. It
looks like the Go team is aware of the issue and planning a fix, so this may
only be needed temporarily.
For some files the Windows Volume Shadow Service (VSS) advertises the
file size as X in the directory listing but returns a different number
Y on stat-ing the file. If the file is opened and read there are Y
bytes available for reading.
Existing copy tools copy Y bytes rather than X so for consistency
rclone should do the same.
This fixes the problem by stat-ing the file immediately before opening
it. This will also reduce the unnecessary occurrence of "can't copy -
source file is being updated" errors; if the file has finished
changing by the time we come to copy it then we now can copy it
successfully.
See: https://forum.rclone.org/t/consistently-getting-corrupted-on-transfer-sizes-differ-syncing-to-an-smb-share/42218/
Before this change if a directory entry could be listed but not
lstat-ed then rclone would give an error and abort the directory
listing with the error
failed to read directory entry: failed to read directory "XXX": lstat XXX
This change makes sure that the directory listing carries on even
after this kind of error.
The sync will be failed but it will carry on.
This problem was caused by a programming error setting the err
variable in an outer scope when it should have been using a local err
variable.
See: https://forum.rclone.org/t/sync-aborts-if-even-one-single-unreadable-folder-is-encountered/39653
Implement a Partialuploads feature flag to mark backends for which
uploads are not atomic.
This is set for the following backends
- local
- ftp
- sftp
See #3770
Before this change using /path/to/file.rclonelink would not find the
file when using -l/--links.
This fixes the problem by doing another stat call if the file wasn't
found without the suffix if -l/--links is in use.
It will also give an error if you refer to a symlink without its
suffix which will not work because the limit to a single file
filtering will be using the file name without the .rclonelink suffix.
need ".rclonelink" suffix to refer to symlink when using -l/--links
Before this change it would use the symlink as a directory which then
would fail when listed.
See: #6855
Before this fix, a dangling symlink was erroring the sync. It was
writing an ERROR log and causing rclone to exit with an error. The
List method wasn't returning an error though.
This fix makes sure that we don't log or report a global error on a
file/directory that has been excluded.
This feature was first implemented in:
a61d219bc local: fix -L/--copy-links with filters missing directories
Then fixed in:
8d1fff9a8 local: obey file filters in listing to fix errors on excluded files
This commit also adds test cases for the failure modes of those commits.
See #6376
In this commit
8d1fff9a82 local: obey file filters in listing to fix errors on excluded files
We introduced the concept of local backend filters.
Unfortunately the filters were being applied before we had resolved
the symlink to point to a directory. This meant that symlinks pointing
to directories were filtered out when they shouldn't have been.
This was fixed by moving the filter check until after the symlink had
been resolved.
See: https://forum.rclone.org/t/copy-links-not-following-symlinks-on-1-60-0/34073/7
In this commit
8d1fff9a82 local: obey file filters in listing to fix errors on excluded files
We started using filters in the local backend so the user could short
circuit troublesome files/directories at a low level.
However this caused a number of integration tests to fail. This turned
out to be in backends wrapping the local backend. For example the
combine backend test failed because it changes the paths passed to the
local backend so they no longer match the paths in the current filter.
To fix this, a new feature flag `FilterAware` was added and the
UseFilter context flag is only passed to backends which support it. As
the wrapping backends don't support the flag, this fixes the problems
in the integration tests.
In future the wrapping backends could modify the active filters to
match the path modifications and then they could set the FilterAware
flag.
See #6376
Before this change, if rclone was run with `-M` on a filesystem
without xattr support, it would error out.
This patch makes rclone detect the not supported errors and disable
xattrs from then on. It prints one ERROR level message about this.
See: https://forum.rclone.org/t/metadata-update-local-s3/32277/7