<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/include/linux/ceph, branch v6.12.80</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>ceph: fix NULL pointer dereference in ceph_mds_auth_match()</title>
<updated>2026-02-11T12:40:16+00:00</updated>
<author>
<name>Viacheslav Dubeyko</name>
<email>Slava.Dubeyko@ibm.com</email>
</author>
<published>2026-02-03T22:54:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=c6f8326f26bd20d648d9a55afd68148d1b6afe28'/>
<id>c6f8326f26bd20d648d9a55afd68148d1b6afe28</id>
<content type='text'>
commit 7987cce375ac8ce98e170a77aa2399f2cf6eb99f upstream.

The CephFS kernel client has regression starting from 6.18-rc1.
We have issue in ceph_mds_auth_match() if fs_name == NULL:

    const char fs_name = mdsc-&gt;fsc-&gt;mount_options-&gt;mds_namespace;
    ...
    if (auth-&gt;match.fs_name &amp;&amp; strcmp(auth-&gt;match.fs_name, fs_name)) {
            / fsname mismatch, try next one */
            return 0;
    }

Patrick Donnelly suggested that: In summary, we should definitely start
decoding `fs_name` from the MDSMap and do strict authorizations checks
against it. Note that the `-o mds_namespace=foo` should only be used for
selecting the file system to mount and nothing else. It's possible
no mds_namespace is specified but the kernel will mount the only
file system that exists which may have name "foo".

This patch reworks ceph_mdsmap_decode() and namespace_equals() with
the goal of supporting the suggested concept. Now struct ceph_mdsmap
contains m_fs_name field that receives copy of extracted FS name
by ceph_extract_encoded_string(). For the case of "old" CephFS file
systems, it is used "cephfs" name.

[ idryomov: replace redundant %*pE with %s in ceph_mdsmap_decode(),
  get rid of a series of strlen() calls in ceph_namespace_match(),
  drop changes to namespace_equals() body to avoid treating empty
  mds_namespace as equal, drop changes to ceph_mdsc_handle_fsmap()
  as namespace_equals() isn't an equivalent substitution there ]

Cc: stable@vger.kernel.org
Fixes: 22c73d52a6d0 ("ceph: fix multifs mds auth caps issue")
Link: https://tracker.ceph.com/issues/73886
Signed-off-by: Viacheslav Dubeyko &lt;Slava.Dubeyko@ibm.com&gt;
Reviewed-by: Patrick Donnelly &lt;pdonnell@ibm.com&gt;
Tested-by: Patrick Donnelly &lt;pdonnell@ibm.com&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 7987cce375ac8ce98e170a77aa2399f2cf6eb99f upstream.

The CephFS kernel client has regression starting from 6.18-rc1.
We have issue in ceph_mds_auth_match() if fs_name == NULL:

    const char fs_name = mdsc-&gt;fsc-&gt;mount_options-&gt;mds_namespace;
    ...
    if (auth-&gt;match.fs_name &amp;&amp; strcmp(auth-&gt;match.fs_name, fs_name)) {
            / fsname mismatch, try next one */
            return 0;
    }

Patrick Donnelly suggested that: In summary, we should definitely start
decoding `fs_name` from the MDSMap and do strict authorizations checks
against it. Note that the `-o mds_namespace=foo` should only be used for
selecting the file system to mount and nothing else. It's possible
no mds_namespace is specified but the kernel will mount the only
file system that exists which may have name "foo".

This patch reworks ceph_mdsmap_decode() and namespace_equals() with
the goal of supporting the suggested concept. Now struct ceph_mdsmap
contains m_fs_name field that receives copy of extracted FS name
by ceph_extract_encoded_string(). For the case of "old" CephFS file
systems, it is used "cephfs" name.

[ idryomov: replace redundant %*pE with %s in ceph_mdsmap_decode(),
  get rid of a series of strlen() calls in ceph_namespace_match(),
  drop changes to namespace_equals() body to avoid treating empty
  mds_namespace as equal, drop changes to ceph_mdsc_handle_fsmap()
  as namespace_equals() isn't an equivalent substitution there ]

Cc: stable@vger.kernel.org
Fixes: 22c73d52a6d0 ("ceph: fix multifs mds auth caps issue")
Link: https://tracker.ceph.com/issues/73886
Signed-off-by: Viacheslav Dubeyko &lt;Slava.Dubeyko@ibm.com&gt;
Reviewed-by: Patrick Donnelly &lt;pdonnell@ibm.com&gt;
Tested-by: Patrick Donnelly &lt;pdonnell@ibm.com&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>move asm/unaligned.h to linux/unaligned.h</title>
<updated>2024-10-02T21:23:23+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2024-10-01T19:35:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=5f60d5f6bbc12e782fac78110b0ee62698f3b576'/>
<id>5f60d5f6bbc12e782fac78110b0ee62698f3b576</id>
<content type='text'>
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
</pre>
</div>
</content>
</entry>
<entry>
<title>ceph: Remove unused declarations</title>
<updated>2024-08-27T07:28:48+00:00</updated>
<author>
<name>Yue Haibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2024-08-14T03:34:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=9a948c0c8e741776ee6d938b49d34d22034fbb7d'/>
<id>9a948c0c8e741776ee6d938b49d34d22034fbb7d</id>
<content type='text'>
These functions is never implemented and used.

Signed-off-by: Yue Haibing &lt;yuehaibing@huawei.com&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
These functions is never implemented and used.

Signed-off-by: Yue Haibing &lt;yuehaibing@huawei.com&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ceph: Use no_printk() helper</title>
<updated>2024-03-19T15:11:42+00:00</updated>
<author>
<name>Geert Uytterhoeven</name>
<email>geert+renesas@glider.be</email>
</author>
<published>2024-02-28T14:00:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=b37cafacbf98ead69c2ecb220fb82b06aee916b9'/>
<id>b37cafacbf98ead69c2ecb220fb82b06aee916b9</id>
<content type='text'>
When printk-indexing is enabled, each printk() invocation emits a
pi_entry structure.  This is even true when the call is protected by an
always-false check: while the actual code to print the message is
optimized out by the compiler, the pi_entry structure is still emitted.

Fix this by replacing "if (0) printk(...)" constructs by calls to the
no_printk() helper.

This reduces the size of an arm64 kernel with CONFIG_PRINTK_INDEX=y and
CONFIG_CEPH_FS=y by ca. 4 KiB.

Signed-off-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Reviewed-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Chris Down &lt;chris@chrisdown.name&gt;
Reviewed-by: Petr Mladek &lt;pmladek@suse.com&gt;
Link: https://lore.kernel.org/r/a21767eccb823435a7f18cdf115d7d572b4e945d.1709127473.git.geert+renesas@glider.be
Signed-off-by: Petr Mladek &lt;pmladek@suse.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When printk-indexing is enabled, each printk() invocation emits a
pi_entry structure.  This is even true when the call is protected by an
always-false check: while the actual code to print the message is
optimized out by the compiler, the pi_entry structure is still emitted.

Fix this by replacing "if (0) printk(...)" constructs by calls to the
no_printk() helper.

This reduces the size of an arm64 kernel with CONFIG_PRINTK_INDEX=y and
CONFIG_CEPH_FS=y by ca. 4 KiB.

Signed-off-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Reviewed-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Chris Down &lt;chris@chrisdown.name&gt;
Reviewed-by: Petr Mladek &lt;pmladek@suse.com&gt;
Link: https://lore.kernel.org/r/a21767eccb823435a7f18cdf115d7d572b4e945d.1709127473.git.geert+renesas@glider.be
Signed-off-by: Petr Mladek &lt;pmladek@suse.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>libceph: just wait for more data to be available on the socket</title>
<updated>2024-02-07T13:43:29+00:00</updated>
<author>
<name>Xiubo Li</name>
<email>xiubli@redhat.com</email>
</author>
<published>2023-12-14T08:01:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=8e46a2d068c92a905d01cbb018b00d66991585ab'/>
<id>8e46a2d068c92a905d01cbb018b00d66991585ab</id>
<content type='text'>
A short read may occur while reading the message footer from the
socket.  Later, when the socket is ready for another read, the
messenger invokes all read_partial_*() handlers, including
read_partial_sparse_msg_data().  The expectation is that
read_partial_sparse_msg_data() would bail, allowing the messenger to
invoke read_partial() for the footer and pick up where it left off.

However read_partial_sparse_msg_data() violates that and ends up
calling into the state machine in the OSD client.  The sparse-read
state machine assumes that it's a new op and interprets some piece of
the footer as the sparse-read header and returns bogus extents/data
length, etc.

To determine whether read_partial_sparse_msg_data() should bail, let's
reuse cursor-&gt;total_resid.  Because once it reaches to zero that means
all the extents and data have been successfully received in last read,
else it could break out when partially reading any of the extents and
data.  And then osd_sparse_read() could continue where it left off.

[ idryomov: changelog ]

Link: https://tracker.ceph.com/issues/63586
Fixes: d396f89db39a ("libceph: add sparse read support to msgr1")
Signed-off-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A short read may occur while reading the message footer from the
socket.  Later, when the socket is ready for another read, the
messenger invokes all read_partial_*() handlers, including
read_partial_sparse_msg_data().  The expectation is that
read_partial_sparse_msg_data() would bail, allowing the messenger to
invoke read_partial() for the footer and pick up where it left off.

However read_partial_sparse_msg_data() violates that and ends up
calling into the state machine in the OSD client.  The sparse-read
state machine assumes that it's a new op and interprets some piece of
the footer as the sparse-read header and returns bogus extents/data
length, etc.

To determine whether read_partial_sparse_msg_data() should bail, let's
reuse cursor-&gt;total_resid.  Because once it reaches to zero that means
all the extents and data have been successfully received in last read,
else it could break out when partially reading any of the extents and
data.  And then osd_sparse_read() could continue where it left off.

[ idryomov: changelog ]

Link: https://tracker.ceph.com/issues/63586
Fixes: d396f89db39a ("libceph: add sparse read support to msgr1")
Signed-off-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>libceph: fail sparse-read if the data length doesn't match</title>
<updated>2024-02-07T13:43:29+00:00</updated>
<author>
<name>Xiubo Li</name>
<email>xiubli@redhat.com</email>
</author>
<published>2023-10-13T05:55:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=cd7d469c25704d414d71bf3644f163fb74e7996b'/>
<id>cd7d469c25704d414d71bf3644f163fb74e7996b</id>
<content type='text'>
Once this happens that means there have bugs.

Signed-off-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Once this happens that means there have bugs.

Signed-off-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ceph: try to allocate a smaller extent map for sparse read</title>
<updated>2024-01-15T14:40:50+00:00</updated>
<author>
<name>Xiubo Li</name>
<email>xiubli@redhat.com</email>
</author>
<published>2023-11-07T02:44:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=aaefabc4a5f7ae48682c4d2d5d10faaf95c08eb9'/>
<id>aaefabc4a5f7ae48682c4d2d5d10faaf95c08eb9</id>
<content type='text'>
In fscrypt case and for a smaller read length we can predict the
max count of the extent map. And for small read length use cases
this could save some memories.

[ idryomov: squash into a single patch to avoid build break, drop
  redundant variable in ceph_alloc_sparse_ext_map() ]

Signed-off-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In fscrypt case and for a smaller read length we can predict the
max count of the extent map. And for small read length use cases
this could save some memories.

[ idryomov: squash into a single patch to avoid build break, drop
  redundant variable in ceph_alloc_sparse_ext_map() ]

Signed-off-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'ceph-for-6.7-rc1' of https://github.com/ceph/ceph-client</title>
<updated>2023-11-10T17:52:56+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-11-10T17:52:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=e21165bfbc6c5d259466a7b2eccb66630e807bfb'/>
<id>e21165bfbc6c5d259466a7b2eccb66630e807bfb</id>
<content type='text'>
Pull ceph updates from Ilya Dryomov:

 - support for idmapped mounts in CephFS (Christian Brauner, Alexander
   Mikhalitsyn).

   The series was originally developed by Christian and later picked up
   and brought over the finish line by Alexander, who also contributed
   an enabler on the MDS side (separate owner_{u,g}id fields on the
   wire).

   The required exports for mnt_idmap_{get,put}() in VFS have been acked
   by Christian and received no objection from Christoph.

 - a churny change in CephFS logging to include cluster and client
   identifiers in log and debug messages (Xiubo Li).

   This would help in scenarios with dozens of CephFS mounts on the same
   node which are getting increasingly common, especially in the
   Kubernetes world.

* tag 'ceph-for-6.7-rc1' of https://github.com/ceph/ceph-client:
  ceph: allow idmapped mounts
  ceph: allow idmapped atomic_open inode op
  ceph: allow idmapped set_acl inode op
  ceph: allow idmapped setattr inode op
  ceph: pass idmap to __ceph_setattr
  ceph: allow idmapped permission inode op
  ceph: allow idmapped getattr inode op
  ceph: pass an idmapping to mknod/symlink/mkdir
  ceph: add enable_unsafe_idmap module parameter
  ceph: handle idmapped mounts in create_request_message()
  ceph: stash idmapping in mdsc request
  fs: export mnt_idmap_get/mnt_idmap_put
  libceph, ceph: move mdsmap.h to fs/ceph
  ceph: print cluster fsid and client global_id in all debug logs
  ceph: rename _to_client() to _to_fs_client()
  ceph: pass the mdsc to several helpers
  libceph: add doutc and *_client debug macros support
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ceph updates from Ilya Dryomov:

 - support for idmapped mounts in CephFS (Christian Brauner, Alexander
   Mikhalitsyn).

   The series was originally developed by Christian and later picked up
   and brought over the finish line by Alexander, who also contributed
   an enabler on the MDS side (separate owner_{u,g}id fields on the
   wire).

   The required exports for mnt_idmap_{get,put}() in VFS have been acked
   by Christian and received no objection from Christoph.

 - a churny change in CephFS logging to include cluster and client
   identifiers in log and debug messages (Xiubo Li).

   This would help in scenarios with dozens of CephFS mounts on the same
   node which are getting increasingly common, especially in the
   Kubernetes world.

* tag 'ceph-for-6.7-rc1' of https://github.com/ceph/ceph-client:
  ceph: allow idmapped mounts
  ceph: allow idmapped atomic_open inode op
  ceph: allow idmapped set_acl inode op
  ceph: allow idmapped setattr inode op
  ceph: pass idmap to __ceph_setattr
  ceph: allow idmapped permission inode op
  ceph: allow idmapped getattr inode op
  ceph: pass an idmapping to mknod/symlink/mkdir
  ceph: add enable_unsafe_idmap module parameter
  ceph: handle idmapped mounts in create_request_message()
  ceph: stash idmapping in mdsc request
  fs: export mnt_idmap_get/mnt_idmap_put
  libceph, ceph: move mdsmap.h to fs/ceph
  ceph: print cluster fsid and client global_id in all debug logs
  ceph: rename _to_client() to _to_fs_client()
  ceph: pass the mdsc to several helpers
  libceph: add doutc and *_client debug macros support
</pre>
</div>
</content>
</entry>
<entry>
<title>ceph: handle idmapped mounts in create_request_message()</title>
<updated>2023-11-03T22:28:33+00:00</updated>
<author>
<name>Christian Brauner</name>
<email>brauner@kernel.org</email>
</author>
<published>2023-08-07T13:26:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=5ccd8530dd7ba97531a50ffa11eabe258d65a7af'/>
<id>5ccd8530dd7ba97531a50ffa11eabe258d65a7af</id>
<content type='text'>
Inode operations that create a new filesystem object such as -&gt;mknod,
-&gt;create, -&gt;mkdir() and others don't take a {g,u}id argument explicitly.
Instead the caller's fs{g,u}id is used for the {g,u}id of the new
filesystem object.

In order to ensure that the correct {g,u}id is used map the caller's
fs{g,u}id for creation requests. This doesn't require complex changes.
It suffices to pass in the relevant idmapping recorded in the request
message. If this request message was triggered from an inode operation
that creates filesystem objects it will have passed down the relevant
idmaping. If this is a request message that was triggered from an inode
operation that doens't need to take idmappings into account the initial
idmapping is passed down which is an identity mapping.

This change uses a new cephfs protocol extension CEPHFS_FEATURE_HAS_OWNER_UIDGID
which adds two new fields (owner_{u,g}id) to the request head structure.
So, we need to ensure that MDS supports it otherwise we need to fail
any IO that comes through an idmapped mount because we can't process it
in a proper way. MDS server without such an extension will use caller_{u,g}id
fields to set a new inode owner UID/GID which is incorrect because caller_{u,g}id
values are unmapped. At the same time we can't map these fields with an
idmapping as it can break UID/GID-based permission checks logic on the
MDS side. This problem was described with a lot of details at [1], [2].

[1] https://lore.kernel.org/lkml/CAEivzxfw1fHO2TFA4dx3u23ZKK6Q+EThfzuibrhA3RKM=ZOYLg@mail.gmail.com/
[2] https://lore.kernel.org/all/20220104140414.155198-3-brauner@kernel.org/

Link: https://github.com/ceph/ceph/pull/52575
Link: https://tracker.ceph.com/issues/62217
Co-Developed-by: Alexander Mikhalitsyn &lt;aleksandr.mikhalitsyn@canonical.com&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
Signed-off-by: Alexander Mikhalitsyn &lt;aleksandr.mikhalitsyn@canonical.com&gt;
Reviewed-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Inode operations that create a new filesystem object such as -&gt;mknod,
-&gt;create, -&gt;mkdir() and others don't take a {g,u}id argument explicitly.
Instead the caller's fs{g,u}id is used for the {g,u}id of the new
filesystem object.

In order to ensure that the correct {g,u}id is used map the caller's
fs{g,u}id for creation requests. This doesn't require complex changes.
It suffices to pass in the relevant idmapping recorded in the request
message. If this request message was triggered from an inode operation
that creates filesystem objects it will have passed down the relevant
idmaping. If this is a request message that was triggered from an inode
operation that doens't need to take idmappings into account the initial
idmapping is passed down which is an identity mapping.

This change uses a new cephfs protocol extension CEPHFS_FEATURE_HAS_OWNER_UIDGID
which adds two new fields (owner_{u,g}id) to the request head structure.
So, we need to ensure that MDS supports it otherwise we need to fail
any IO that comes through an idmapped mount because we can't process it
in a proper way. MDS server without such an extension will use caller_{u,g}id
fields to set a new inode owner UID/GID which is incorrect because caller_{u,g}id
values are unmapped. At the same time we can't map these fields with an
idmapping as it can break UID/GID-based permission checks logic on the
MDS side. This problem was described with a lot of details at [1], [2].

[1] https://lore.kernel.org/lkml/CAEivzxfw1fHO2TFA4dx3u23ZKK6Q+EThfzuibrhA3RKM=ZOYLg@mail.gmail.com/
[2] https://lore.kernel.org/all/20220104140414.155198-3-brauner@kernel.org/

Link: https://github.com/ceph/ceph/pull/52575
Link: https://tracker.ceph.com/issues/62217
Co-Developed-by: Alexander Mikhalitsyn &lt;aleksandr.mikhalitsyn@canonical.com&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
Signed-off-by: Alexander Mikhalitsyn &lt;aleksandr.mikhalitsyn@canonical.com&gt;
Reviewed-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>libceph, ceph: move mdsmap.h to fs/ceph</title>
<updated>2023-11-03T22:28:33+00:00</updated>
<author>
<name>Xiubo Li</name>
<email>xiubli@redhat.com</email>
</author>
<published>2023-06-12T07:41:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=522dc5108f07ef30e2c7399e59b9547d382308ff'/>
<id>522dc5108f07ef30e2c7399e59b9547d382308ff</id>
<content type='text'>
The mdsmap.h is only used by CephFS, so move it to fs/ceph.

Signed-off-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The mdsmap.h is only used by CephFS, so move it to fs/ceph.

Signed-off-by: Xiubo Li &lt;xiubli@redhat.com&gt;
Reviewed-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
Signed-off-by: Ilya Dryomov &lt;idryomov@gmail.com&gt;
</pre>
</div>
</content>
</entry>
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