linux-stable.git/fs, branch v6.6.82

afs: Fix the server_list to unuse a displaced server rather than putting it

2025-03-07T15:45:38+00:00

[ Upstream commit add117e48df4788a86a21bd0515833c0a6db1ad1 ]

When allocating and building an afs_server_list struct object from a VLDB
record, we look up each server address to get the server record for it -
but a server may have more than one entry in the record and we discard the
duplicate pointers.  Currently, however, when we discard, we only put a
server record, not unuse it - but the lookup got as an active-user count.

The active-user count on an afs_server_list object determines its lifetime
whereas the refcount keeps the memory backing it around.  Failing to reduce
the active-user counter prevents the record from being cleaned up and can
lead to multiple copied being seen - and pointing to deleted afs_cell
objects and other such things.

Fix this by switching the incorrect 'put' to an 'unuse' instead.

Without this, occasionally, a dead server record can be seen in
/proc/net/afs/servers and list corruption may be observed:

    list_del corruption. prev->next should be ffff888102423e40, but was 0000000000000000. (prev=ffff88810140cd38)

Fixes: 977e5f8ed0ab ("afs: Split the usage count on struct afs_server")
Signed-off-by: David Howells 
cc: Marc Dionne 
cc: Simon Horman 
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20250218192250.296870-5-dhowells@redhat.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

afs: Make it possible to find the volumes that are using a server

2025-03-07T15:45:38+00:00

[ Upstream commit ca0e79a46097d54e4af46c67c852479d97af35bb ]

Make it possible to find the afs_volume structs that are using an
afs_server struct to aid in breaking volume callbacks.

The way this is done is that each afs_volume already has an array of
afs_server_entry records that point to the servers where that volume might
be found.  An afs_volume backpointer and a list node is added to each entry
and each entry is then added to an RCU-traversable list on the afs_server
to which it points.

Signed-off-by: David Howells 
cc: Marc Dionne 
cc: linux-afs@lists.infradead.org
Stable-dep-of: add117e48df4 ("afs: Fix the server_list to unuse a displaced server rather than putting it")
Signed-off-by: Sasha Levin

ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up

2025-03-07T15:45:36+00:00

[ Upstream commit c84e125fff2615b4d9c259e762596134eddd2f27 ]

The issue was caused by dput(upper) being called before
ovl_dentry_update_reval(), while upper->d_flags was still
accessed in ovl_dentry_remote().

Move dput(upper) after its last use to prevent use-after-free.

BUG: KASAN: slab-use-after-free in ovl_dentry_remote fs/overlayfs/util.c:162 [inline]
BUG: KASAN: slab-use-after-free in ovl_dentry_update_reval+0xd2/0xf0 fs/overlayfs/util.c:167

Call Trace:
 
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 ovl_dentry_remote fs/overlayfs/util.c:162 [inline]
 ovl_dentry_update_reval+0xd2/0xf0 fs/overlayfs/util.c:167
 ovl_link_up fs/overlayfs/copy_up.c:610 [inline]
 ovl_copy_up_one+0x2105/0x3490 fs/overlayfs/copy_up.c:1170
 ovl_copy_up_flags+0x18d/0x200 fs/overlayfs/copy_up.c:1223
 ovl_rename+0x39e/0x18c0 fs/overlayfs/dir.c:1136
 vfs_rename+0xf84/0x20a0 fs/namei.c:4893
...
 

Fixes: b07d5cc93e1b ("ovl: update of dentry revalidate flags after copy up")
Reported-by: syzbot+316db8a1191938280eb6@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=316db8a1191938280eb6
Signed-off-by: Vasiliy Kovalev 
Link: https://lore.kernel.org/r/20250214215148.761147-1-kovalev@altlinux.org
Reviewed-by: Amir Goldstein 
Signed-off-by: Christian Brauner 
Signed-off-by: Sasha Levin

nilfs2: handle errors that nilfs_prepare_chunk() may return

2025-02-27T12:10:54+00:00

commit ee70999a988b8abc3490609142f50ebaa8344432 upstream.

Patch series "nilfs2: fix issues with rename operations".

This series fixes BUG_ON check failures reported by syzbot around rename
operations, and a minor behavioral issue where the mtime of a child
directory changes when it is renamed instead of moved.

This patch (of 2):

The directory manipulation routines nilfs_set_link() and
nilfs_delete_entry() rewrite the directory entry in the folio/page
previously read by nilfs_find_entry(), so error handling is omitted on the
assumption that nilfs_prepare_chunk(), which prepares the buffer for
rewriting, will always succeed for these.  And if an error is returned, it
triggers the legacy BUG_ON() checks in each routine.

This assumption is wrong, as proven by syzbot: the buffer layer called by
nilfs_prepare_chunk() may call nilfs_get_block() if necessary, which may
fail due to metadata corruption or other reasons.  This has been there all
along, but improved sanity checks and error handling may have made it more
reproducible in fuzzing tests.

Fix this issue by adding missing error paths in nilfs_set_link(),
nilfs_delete_entry(), and their caller nilfs_rename().

[konishi.ryusuke@gmail.com: adjusted for page/folio conversion]
Link: https://lkml.kernel.org/r/20250111143518.7901-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20250111143518.7901-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi 
Reported-by: syzbot+32c3706ebf5d95046ea1@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=32c3706ebf5d95046ea1
Reported-by: syzbot+1097e95f134f37d9395c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1097e95f134f37d9395c
Fixes: 2ba466d74ed7 ("nilfs2: directory entry operations")
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

nilfs2: eliminate staggered calls to kunmap in nilfs_rename

2025-02-27T12:10:54+00:00

commit 8cf57c6df818f58fdad16a909506be213623a88e upstream.

In nilfs_rename(), calls to nilfs_put_page() to release pages obtained
with nilfs_find_entry() or nilfs_dotdot() are alternated in the normal
path.

When replacing the kernel memory mapping method from kmap to
kmap_local_{page,folio}, this violates the constraint on the calling order
of kunmap_local().

Swap the order of nilfs_put_page calls where the kmap sections of multiple
pages overlap so that they are nested, allowing direct replacement of
nilfs_put_page() -> unmap_and_put_page().

Without this reordering, that replacement will cause a kernel WARNING in
kunmap_local_indexed() on architectures with high memory mapping.

Link: https://lkml.kernel.org/r/20231127143036.2425-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi 
Reviewed-by: Matthew Wilcox (Oracle) 
Signed-off-by: Andrew Morton 
Stable-dep-of: ee70999a988b ("nilfs2: handle errors that nilfs_prepare_chunk() may return")
Signed-off-by: Greg Kroah-Hartman

nilfs2: move page release outside of nilfs_delete_entry and nilfs_set_link

2025-02-27T12:10:53+00:00

commit 584db20c181f5e28c0386d7987406ace7fbd3e49 upstream.

Patch series "nilfs2: Folio conversions for directory paths".

This series applies page->folio conversions to nilfs2 directory
operations.  This reduces hidden compound_head() calls and also converts
deprecated kmap calls to kmap_local in the directory code.

Although nilfs2 does not yet support large folios, Matthew has done his
best here to include support for large folios, which will be needed for
devices with large block sizes.

This series corresponds to the second half of the original post [1], but
with two complementary patches inserted at the beginning and some
adjustments, to prevent a kmap_local constraint violation found during
testing with highmem mapping.

[1] https://lkml.kernel.org/r/20231106173903.1734114-1-willy@infradead.org

I have reviewed all changes and tested this for regular and small block
sizes, both on machines with and without highmem mapping.  No issues
found.

This patch (of 17):

In a few directory operations, the call to nilfs_put_page() for a page
obtained using nilfs_find_entry() or nilfs_dotdot() is hidden in
nilfs_set_link() and nilfs_delete_entry(), making it difficult to track
page release and preventing change of its call position.

By moving nilfs_put_page() out of these functions, this makes the page
get/put correspondence clearer and makes it easier to swap
nilfs_put_page() calls (and kunmap calls within them) when modifying
multiple directory entries simultaneously in nilfs_rename().

Also, update comments for nilfs_set_link() and nilfs_delete_entry() to
reflect changes in their behavior.

To make nilfs_put_page() visible from namei.c, this moves its definition
to nilfs.h and replaces existing equivalents to use it, but the exposure
of that definition is temporary and will be removed on a later kmap ->
kmap_local conversion.

Link: https://lkml.kernel.org/r/20231127143036.2425-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20231127143036.2425-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi 
Reviewed-by: Matthew Wilcox (Oracle) 
Signed-off-by: Andrew Morton 
Stable-dep-of: ee70999a988b ("nilfs2: handle errors that nilfs_prepare_chunk() may return")
Signed-off-by: Greg Kroah-Hartman

smb: client: Add check for next_buffer in receive_encrypted_standard()

2025-02-27T12:10:53+00:00

commit 860ca5e50f73c2a1cef7eefc9d39d04e275417f7 upstream.

Add check for the return value of cifs_buf_get() and cifs_small_buf_get()
in receive_encrypted_standard() to prevent null pointer dereference.

Fixes: eec04ea11969 ("smb: client: fix OOB in receive_encrypted_standard()")
Cc: stable@vger.kernel.org
Signed-off-by: Haoxiang Li 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

xfs: don't over-report free space or inodes in statvfs

2025-02-27T12:10:44+00:00

[ Upstream commit 4b8d867ca6e2fc6d152f629fdaf027053b81765a ]

Emmanual Florac reports a strange occurrence when project quota limits
are enabled, free space is lower than the remaining quota, and someone
runs statvfs:

  # mkfs.xfs -f /dev/sda
  # mount /dev/sda /mnt -o prjquota
  # xfs_quota  -x -c 'limit -p bhard=2G 55' /mnt
  # mkdir /mnt/dir
  # xfs_io -c 'chproj 55' -c 'chattr +P' -c 'stat -vvvv' /mnt/dir
  # fallocate -l 19g /mnt/a
  # df /mnt /mnt/dir
  Filesystem      Size  Used Avail Use% Mounted on
  /dev/sda         20G   20G  345M  99% /mnt
  /dev/sda        2.0G     0  2.0G   0% /mnt

I think the bug here is that xfs_fill_statvfs_from_dquot unconditionally
assigns to f_bfree without checking that the filesystem has enough free
space to fill the remaining project quota.  However, this is a
longstanding behavior of xfs so it's unclear what to do here.

Cc:  # v2.6.18
Fixes: 932f2c323196c2 ("[XFS] statvfs component of directory/project quota support, code originally by Glen.")
Reported-by: Emmanuel Florac 
Signed-off-by: "Darrick J. Wong" 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Sasha Levin

xfs: report realtime block quota limits on realtime directories

2025-02-27T12:10:44+00:00

[ Upstream commit 9a17ebfea9d0c7e0bb7409dcf655bf982a5d6e52 ]

On the data device, calling statvfs on a projinherit directory results
in the block and avail counts being curtailed to the project quota block
limits, if any are set.  Do the same for realtime files or directories,
only use the project quota rt block limits.

Signed-off-by: Darrick J. Wong 
Reviewed-by: Christoph Hellwig 
Stable-dep-of: 4b8d867ca6e2 ("xfs: don't over-report free space or inodes in statvfs")
Signed-off-by: Sasha Levin

xfs: Check for delayed allocations before setting extsize

2025-02-27T12:10:44+00:00

commit 2a492ff66673c38a77d0815d67b9a8cce2ef57f8 upstream.

Extsize should only be allowed to be set on files with no data in it.
For this, we check if the files have extents but miss to check if
delayed extents are present. This patch adds that check.

While we are at it, also refactor this check into a helper since
it's used in some other places as well like xfs_inactive() or
xfs_ioctl_setattr_xflags()

**Without the patch (SUCCEEDS)**

$ xfs_io -c 'open -f testfile' -c 'pwrite 0 1024' -c 'extsize 65536'

wrote 1024/1024 bytes at offset 0
1 KiB, 1 ops; 0.0002 sec (4.628 MiB/sec and 4739.3365 ops/sec)

**With the patch (FAILS as expected)**

$ xfs_io -c 'open -f testfile' -c 'pwrite 0 1024' -c 'extsize 65536'

wrote 1024/1024 bytes at offset 0
1 KiB, 1 ops; 0.0002 sec (4.628 MiB/sec and 4739.3365 ops/sec)
xfs_io: FS_IOC_FSSETXATTR testfile: Invalid argument

Fixes: e94af02a9cd7 ("[XFS] fix old xfs_setattr mis-merge from irix; mostly harmless esp if not using xfs rt")
Reviewed-by: Christoph Hellwig 
Reviewed-by: Darrick J. Wong 
Reviewed-by: John Garry 
Signed-off-by: Ojaswin Mujoo 
Signed-off-by: Carlos Maiolino 
Signed-off-by: Catherine Hoang 
Acked-by: Darrick J. Wong 
Signed-off-by: Greg Kroah-Hartman