These two are backports for 6.1.y. Conflict resolution in done in both patches.
I have tested LTP-nfs fchown02 and chown02 on 6.1.y with below patches applied. The tests passed.
I would like to have a review as I am not familiar with this code.
Thanks to Vegard for helping me with this.
Thanks, Harshit
Christian Brauner (2): nfs: use vfs setgid helper nfsd: use vfs setgid helper
fs/attr.c | 1 + fs/internal.h | 2 -- fs/nfs/inode.c | 4 +--- fs/nfsd/vfs.c | 4 +++- include/linux/fs.h | 2 ++ 5 files changed, 7 insertions(+), 6 deletions(-)
From: Christian Brauner brauner@kernel.org
commit 4f704d9a8352f5c0a8fcdb6213b934630342bd44 upstream.
We've aligned setgid behavior over multiple kernel releases. The details can be found in the following two merge messages: cf619f891971 ("Merge tag 'fs.ovl.setgid.v6.2') 426b4ca2d6a5 ("Merge tag 'fs.setgid.v6.0') Consistent setgid stripping behavior is now encapsulated in the setattr_should_drop_sgid() helper which is used by all filesystems that strip setgid bits outside of vfs proper. Switch nfs to rely on this helper as well. Without this patch the setgid stripping tests in xfstests will fail.
Signed-off-by: Christian Brauner (Microsoft) brauner@kernel.org Reviewed-by: Christoph Hellwig hch@lst.de Message-Id: 20230313-fs-nfs-setgid-v2-1-9a59f436cfc0@kernel.org Signed-off-by: Christian Brauner brauner@kernel.org [Harshit: backport to 6.1.y] Conflicts: fs/internal.h -- minor conflict due to code change differences. include/linux/fs.h -- Used struct user_namespace *mnt_userns instead of struct mnt_idmap *idmap fs/nfs/inode.c -- Used init_user_ns instead of nop_mnt_idmap
Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com --- fs/attr.c | 1 + fs/internal.h | 2 -- fs/nfs/inode.c | 4 +--- include/linux/fs.h | 2 ++ 4 files changed, 4 insertions(+), 5 deletions(-)
diff --git a/fs/attr.c b/fs/attr.c index b45f30e516fa..9b9a70e0cc54 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -47,6 +47,7 @@ int setattr_should_drop_sgid(struct user_namespace *mnt_userns, return ATTR_KILL_SGID; return 0; } +EXPORT_SYMBOL(setattr_should_drop_sgid);
/** * setattr_should_drop_suidgid - determine whether the set{g,u}id bit needs to diff --git a/fs/internal.h b/fs/internal.h index 46caa33373a4..42df013f7fe7 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -242,5 +242,3 @@ ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *po /* * fs/attr.c */ -int setattr_should_drop_sgid(struct user_namespace *mnt_userns, - const struct inode *inode); diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 6b2cfa59a1a2..e0c1fb98f907 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -717,9 +717,7 @@ void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr, if ((attr->ia_valid & ATTR_KILL_SUID) != 0 && inode->i_mode & S_ISUID) inode->i_mode &= ~S_ISUID; - if ((attr->ia_valid & ATTR_KILL_SGID) != 0 && - (inode->i_mode & (S_ISGID | S_IXGRP)) == - (S_ISGID | S_IXGRP)) + if (setattr_should_drop_sgid(&init_user_ns, inode)) inode->i_mode &= ~S_ISGID; if ((attr->ia_valid & ATTR_MODE) != 0) { int mode = attr->ia_mode & S_IALLUGO; diff --git a/include/linux/fs.h b/include/linux/fs.h index a2b5592c6828..26ea1a0a59a1 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3120,6 +3120,8 @@ extern struct inode *new_inode(struct super_block *sb); extern void free_inode_nonrcu(struct inode *inode); extern int setattr_should_drop_suidgid(struct user_namespace *, struct inode *); extern int file_remove_privs(struct file *); +int setattr_should_drop_sgid(struct user_namespace *mnt_userns, + const struct inode *inode);
/* * This must be used for allocating filesystems specific inodes to set
From: Christian Brauner brauner@kernel.org
commit 2d8ae8c417db284f598dffb178cc01e7db0f1821 upstream.
We've aligned setgid behavior over multiple kernel releases. The details can be found in commit cf619f891971 ("Merge tag 'fs.ovl.setgid.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping") and commit 426b4ca2d6a5 ("Merge tag 'fs.setgid.v6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux"). Consistent setgid stripping behavior is now encapsulated in the setattr_should_drop_sgid() helper which is used by all filesystems that strip setgid bits outside of vfs proper. Usually ATTR_KILL_SGID is raised in e.g., chown_common() and is subject to the setattr_should_drop_sgid() check to determine whether the setgid bit can be retained. Since nfsd is raising ATTR_KILL_SGID unconditionally it will cause notify_change() to strip it even if the caller had the necessary privileges to retain it. Ensure that nfsd only raises ATR_KILL_SGID if the caller lacks the necessary privileges to retain the setgid bit.
Without this patch the setgid stripping tests in LTP will fail:
As you can see, the problem is S_ISGID (0002000) was dropped on a non-group-executable file while chown was invoked by super-user, while
[...]
fchown02.c:66: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700
[...]
chown02.c:57: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700
With this patch all tests pass.
Reported-by: Sherry Yang sherry.yang@oracle.com Signed-off-by: Christian Brauner brauner@kernel.org Reviewed-by: Jeff Layton jlayton@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com [Harshit: backport to 6.1.y: Use init_user_ns instead of nop_mnt_idmap as we don't have commit abf08576afe3 ("fs: port vfs_*() helpers to struct mnt_idmap")] Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com --- fs/nfsd/vfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 155b34c4683c..4c11046800ab 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -321,7 +321,9 @@ nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap) iap->ia_mode &= ~S_ISGID; } else { /* set ATTR_KILL_* bits and let VFS handle it */ - iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID); + iap->ia_valid |= ATTR_KILL_SUID; + iap->ia_valid |= + setattr_should_drop_sgid(&init_user_ns, inode); } } }
Hello!
On Fri, 25 Aug 2023 at 10:17, Harshit Mogalapalli harshit.m.mogalapalli@oracle.com wrote:
These two are backports for 6.1.y. Conflict resolution in done in both patches. I have tested LTP-nfs fchown02 and chown02 on 6.1.y with below patches applied. The tests passed.
I have given this a go but did not see better results.
On 6.1.48-rc1, without any extra patches: https://lkft.validation.linaro.org/scheduler/job/6685964#L3814 https://storage.tuxsuite.com/public/linaro/lkft/builds/2UR2OCpseRQ0lu76phKZB...
On 6.1.48-rc1 plus this series of patches: https://lkft.validation.linaro.org/scheduler/job/6692637#L3832 https://lkft.validation.linaro.org/scheduler/job/6692642#L3818 https://storage.tuxsuite.com/public/linaro/daniel/builds/2UUHtMsTAQeuei3gGM3...
In both cases: chown02.c:46: TPASS: chown(testfile1, 0, 0) passed chown02.c:46: TPASS: chown(testfile2, 0, 0) passed chown02.c:58: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700 [...] fchown02.c:57: TPASS: fchown(3, 0, 0) passed fchown02.c:57: TPASS: fchown(4, 0, 0) passed fchown02.c:67: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700
The exact same thing happened with the 5.15 patch series.
I'll be glad to test more patches.
Greetings!
Daniel Díaz daniel.diaz@linaro.org
I would like to have a review as I am not familiar with this code.
Thanks to Vegard for helping me with this.
Thanks, Harshit
Christian Brauner (2): nfs: use vfs setgid helper nfsd: use vfs setgid helper
fs/attr.c | 1 + fs/internal.h | 2 -- fs/nfs/inode.c | 4 +--- fs/nfsd/vfs.c | 4 +++- include/linux/fs.h | 2 ++ 5 files changed, 7 insertions(+), 6 deletions(-)
-- 2.34.1
Hi Daniel,
On 26/08/23 4:41 am, Daniel Díaz wrote:
Hello!
On Fri, 25 Aug 2023 at 10:17, Harshit Mogalapalli harshit.m.mogalapalli@oracle.com wrote:
These two are backports for 6.1.y. Conflict resolution in done in both patches. I have tested LTP-nfs fchown02 and chown02 on 6.1.y with below patches applied. The tests passed.
I have given this a go but did not see better results.
On 6.1.48-rc1, without any extra patches: https://lkft.validation.linaro.org/scheduler/job/6685964#L3814 https://storage.tuxsuite.com/public/linaro/lkft/builds/2UR2OCpseRQ0lu76phKZB...
On 6.1.48-rc1 plus this series of patches: https://lkft.validation.linaro.org/scheduler/job/6692637#L3832 https://lkft.validation.linaro.org/scheduler/job/6692642#L3818 https://storage.tuxsuite.com/public/linaro/daniel/builds/2UUHtMsTAQeuei3gGM3...
In both cases: chown02.c:46: TPASS: chown(testfile1, 0, 0) passed chown02.c:46: TPASS: chown(testfile2, 0, 0) passed chown02.c:58: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700 [...] fchown02.c:57: TPASS: fchown(3, 0, 0) passed fchown02.c:57: TPASS: fchown(4, 0, 0) passed fchown02.c:67: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700
The exact same thing happened with the 5.15 patch series.
Odd, I just tested 5.15 based kernel again.
Unpatched kernel:
<<<test_start>>> tag=fchown02 stime=1693034274 cmdline="fchown02" contacts="" analysis=exit <<<test_output>>> tst_test.c:1561: TINFO: Timeout per run is 0h 00m 30s fchown02.c:58: TPASS: fchown(3, 0, 0) passed fchown02.c:58: TPASS: fchown(4, 0, 0) passed fchown02.c:68: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700
Summary: passed 2 failed 1 broken 0 skipped 0 warnings 0
-----------
patched kernel:
<<<test_start>>> tag=fchown02 stime=1693034615 cmdline="fchown02" contacts="" analysis=exit <<<test_output>>> tst_test.c:1561: TINFO: Timeout per run is 0h 00m 30s fchown02.c:58: TPASS: fchown(3, 0, 0) passed fchown02.c:58: TPASS: fchown(4, 0, 0) passed
Summary: passed 2 failed 0 broken 0 skipped 0 warnings 0
Test steps:
mkdir /tmpdir
yum install nfs-utils -y echo "/media *(rw,no_root_squash,sync)" >/etc/exports systemctl start nfs-server.service mount -o rw,nfsvers=4 127.0.0.1:/media /tmpdir cd /opt/ltp/ ./runltp -d /tmpdir -s fchown02
Thanks for testing.
Regards, Harshit
I'll be glad to test more patches.
Greetings!
Daniel Díaz daniel.diaz@linaro.org
I would like to have a review as I am not familiar with this code.
Thanks to Vegard for helping me with this.
Thanks, Harshit
Christian Brauner (2): nfs: use vfs setgid helper nfsd: use vfs setgid helper
fs/attr.c | 1 + fs/internal.h | 2 -- fs/nfs/inode.c | 4 +--- fs/nfsd/vfs.c | 4 +++- include/linux/fs.h | 2 ++ 5 files changed, 7 insertions(+), 6 deletions(-)
-- 2.34.1
On Fri, Aug 25, 2023 at 09:16:01AM -0700, Harshit Mogalapalli wrote:
These two are backports for 6.1.y. Conflict resolution in done in both patches.
I have tested LTP-nfs fchown02 and chown02 on 6.1.y with below patches applied. The tests passed.
I would like to have a review as I am not familiar with this code.
Thanks to Vegard for helping me with this.
Thanks, Harshit
Christian Brauner (2): nfs: use vfs setgid helper nfsd: use vfs setgid helper
fs/attr.c | 1 + fs/internal.h | 2 -- fs/nfs/inode.c | 4 +--- fs/nfsd/vfs.c | 4 +++- include/linux/fs.h | 2 ++ 5 files changed, 7 insertions(+), 6 deletions(-)
-- 2.34.1
All now queued up, thanks.
greg k-h
linux-stable-mirror@lists.linaro.org
-
Daniel Díaz -
Greg KH -
Harshit Mogalapalli