Intentionally allow ZFS_READONLY in zfs_write #11693
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
ZFS_READONLY represents the "DOS R/O" attribute. When that flag is set, we should behave as if write access were not granted by anything in the ACL. In particular: We _must_ allow writes after opening the file r/w, then setting the DOS R/O attribute, and writing some more. (Similar to how you can write after fchmod(fd, 0444).) Restore these semantics which were lost on FreeBSD when refactoring zfs_write. To my knowledge Linux does not actually expose this flag, but we'll need it to eventually so I've added the supporting checks. Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
ghost
added
the
Could you perhaps add it to the ZTS as part of this PR please? Even if it's only enabled on FreeBSD. |
behlendorf
approved these changes
Mar 5, 2021
I'll clean that up and hook it in to ZTS separately when I get a chance next week. It doesn't need to block this PR. |
ghost
deleted the
behlendorf
pushed a commit
that referenced
this pull request
Mar 8, 2021
ZFS_READONLY represents the "DOS R/O" attribute. When that flag is set, we should behave as if write access were not granted by anything in the ACL. In particular: We _must_ allow writes after opening the file r/w, then setting the DOS R/O attribute, and writing some more. (Similar to how you can write after fchmod(fd, 0444).) Restore these semantics which were lost on FreeBSD when refactoring zfs_write. To my knowledge Linux does not actually expose this flag, but we'll need it to eventually so I've added the supporting checks. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Ryan Moeller <ryan@iXsystems.com> Closes #11693
jsai20
pushed a commit
to jsai20/zfs
that referenced
this pull request
Mar 30, 2021
ZFS_READONLY represents the "DOS R/O" attribute. When that flag is set, we should behave as if write access were not granted by anything in the ACL. In particular: We _must_ allow writes after opening the file r/w, then setting the DOS R/O attribute, and writing some more. (Similar to how you can write after fchmod(fd, 0444).) Restore these semantics which were lost on FreeBSD when refactoring zfs_write. To my knowledge Linux does not actually expose this flag, but we'll need it to eventually so I've added the supporting checks. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Ryan Moeller <ryan@iXsystems.com> Closes openzfs#11693
adamdmoss
pushed a commit
to adamdmoss/zfs
that referenced
this pull request
Apr 10, 2021
ZFS_READONLY represents the "DOS R/O" attribute. When that flag is set, we should behave as if write access were not granted by anything in the ACL. In particular: We _must_ allow writes after opening the file r/w, then setting the DOS R/O attribute, and writing some more. (Similar to how you can write after fchmod(fd, 0444).) Restore these semantics which were lost on FreeBSD when refactoring zfs_write. To my knowledge Linux does not actually expose this flag, but we'll need it to eventually so I've added the supporting checks. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Ryan Moeller <ryan@iXsystems.com> Closes openzfs#11693
sempervictus
pushed a commit
to sempervictus/zfs
that referenced
this pull request
May 31, 2021
ZFS_READONLY represents the "DOS R/O" attribute. When that flag is set, we should behave as if write access were not granted by anything in the ACL. In particular: We _must_ allow writes after opening the file r/w, then setting the DOS R/O attribute, and writing some more. (Similar to how you can write after fchmod(fd, 0444).) Restore these semantics which were lost on FreeBSD when refactoring zfs_write. To my knowledge Linux does not actually expose this flag, but we'll need it to eventually so I've added the supporting checks. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Ryan Moeller <ryan@iXsystems.com> Closes openzfs#11693
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Motivation and Context
ZFS_READONLY represents the "DOS R/O" attribute.
When that flag is set, we should behave as if write access
were not granted by anything in the ACL. In particular:
We must allow writes after opening the file r/w, then
setting the DOS R/O attribute, and writing some more.
(Similar to how you can write after fchmod(fd, 0444).)
Description
Restore these semantics which were lost on FreeBSD when refactoring
zfs_write. To my knowledge Linux does not actually expose this flag,
but we'll need it to eventually so I've added the supporting checks.
How Has This Been Tested?
A small test program for FreeBSD was provided to me. It opens a file, sets the readonly flag, then tries to write.
ZTS sanity tests were also run on Linux and FreeBSD.
Types of changes
Checklist:
Signed-off-by.