This fixes an inifinite loop in mkdirAs(), used by `MkdirAllAndChown`,
`MkdirAndChown`, and `MkdirAllAndChownNew`, as well as directories being
chown'd multiple times when relative paths are used.
The for loop in this function was incorrectly assuming that;
1. `filepath.Dir()` would always return the parent directory of any given path
2. traversing any given path to ultimately result in "/"
While this is correct for absolute and "cleaned" paths, both assumptions are
incorrect in some variations of "path";
1. for paths with a trailing path-separator ("some/path/"), or dot ("."),
`filepath.Dir()` considers the (implicit) "." to be a location _within_ the
directory, and returns "some/path" as ("parent") directory. This resulted
in the path itself to be included _twice_ in the list of paths to chown.
2. for relative paths ("./some-path", "../some-path"), "traversing" the path
would never end in "/", causing the for loop to run indefinitely:
```go
// walk back to "/" looking for directories which do not exist
// and add them to the paths array for chown after creation
dirPath := path
for {
dirPath = filepath.Dir(dirPath)
if dirPath == "/" {
break
}
if _, err := os.Stat(dirPath); err != nil && os.IsNotExist(err) {
paths = append(paths, dirPath)
}
}
```
A _partial_ mitigation for this would be to use `filepath.Clean()` before using
the path (while `filepath.Dir()` _does_ call `filepath.Clean()`, it only does so
_after_ some processing, so only cleans the result). Doing so would prevent the
double chown from happening, but would not prevent the "final" path to be "."
or ".." (in the relative path case), still causing an infinite loop, or
additional checks for "." / ".." to be needed.
| path | filepath.Dir(path) | filepath.Dir(filepath.Clean(path)) |
|----------------|--------------------|------------------------------------|
| some-path | . | . |
| ./some-path | . | . |
| ../some-path | .. | .. |
| some/path/ | some/path | some |
| ./some/path/ | some/path | some |
| ../some/path/ | ../some/path | ../some |
| some/path/. | some/path | some |
| ./some/path/. | some/path | some |
| ../some/path/. | ../some/path | ../some |
| /some/path/ | /some/path | /some |
| /some/path/. | /some/path | /some |
Instead, this patch adds a `filepath.Abs()` to the function, so make sure that
paths are both cleaned, and not resulting in an infinite loop.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 1e13247d6d)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Finish the refactor which was partially completed with commit
34536c498d, passing around IdentityMapping structs instead of pairs of
[]IDMap slices.
Existing code which uses []IDMap relies on zero-valued fields to be
valid, empty mappings. So in order to successfully finish the
refactoring without introducing bugs, their replacement therefore also
needs to have a useful zero value which represents an empty mapping.
Change IdentityMapping to be a pass-by-value type so that there are no
nil pointers to worry about.
The functionality provided by the deprecated NewIDMappingsFromMaps
function is required by unit tests to to construct arbitrary
IdentityMapping values. And the daemon will always need to access the
mappings to pass them to the Linux kernel. Accommodate these use cases
by exporting the struct fields instead. BuildKit currently depends on
the UIDs and GIDs methods so we cannot get rid of them yet.
Signed-off-by: Cory Snider <csnider@mirantis.com>
The io/ioutil package has been deprecated in Go 1.16. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
NewIdentityMapping took group name as an argument, and used
the group name also to parse the /etc/sub{uid,gui}. But as per
linux man pages, the sub{uid,gid} file maps username or uid,
not a group name.
Therefore, all occurrences where mapping is used need to
consider only username and uid. Code trying to map using gid
and group name in the daemon is also removed.
Signed-off-by: Akhil Mohan <akhil.mohan@mayadata.io>
This implements chown support on Windows. Built-in accounts as well
as accounts included in the SAM database of the container are supported.
NOTE: IDPair is now named Identity and IDMappings is now named
IdentityMapping.
The following are valid examples:
ADD --chown=Guest . <some directory>
COPY --chown=Administrator . <some directory>
COPY --chown=Guests . <some directory>
COPY --chown=ContainerUser . <some directory>
On Windows an owner is only granted the permission to read the security
descriptor and read/write the discretionary access control list. This
fix also grants read/write and execute permissions to the owner.
Signed-off-by: Salahuddin Khan <salah@docker.com>
It should check `os.Geteuid` with `uid` instead of `os.Getegid`.
On the container (where the tests run), the uid and gid seems to be
the same, thus this doesn't fail.
Signed-off-by: Vincent Demeester <vincent@sbr.pm>
Standard golang's `os.MkdirAll()` function returns "not a directory" error
in case a directory to be created already exists but is not a directory
(e.g. a file). Our own `idtools.MkdirAs*()` functions do not replicate
the behavior.
This is a bug since all `Mkdir()`-like functions are expected to ensure
the required directory exists and is indeed a directory, and return an
error otherwise.
As the code is using our in-house `system.Stat()` call returning a type
which is incompatible with that of golang's `os.Stat()`, I had to amend
the `system` package with `IsDir()`.
A test case is also provided.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Switch some more usage of the Stat function and the Stat_t type from the
syscall package to golang.org/x/sys. Those were missing in PR #33399.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Since Docker is already skipping newlines in /etc/sub{uid,gid},
this patch skips commented out lines - otherwise Docker fails to start.
Add unit test also.
Signed-off-by: Antonio Murdaca <runcom@redhat.com>
This fixes errors in ownership on directory creation during build that
can cause inaccessible files depending on the paths in the Dockerfile
and non-existing directories in the starting image.
Add tests for the mkdir variants in pkg/idtools
Docker-DCO-1.1-Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com> (github: estesp)
