linux-stable.git/fs/jffs2, branch v6.2

fs: rename current get acl method

2022-10-20T08:13:27+00:00

The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

The current inode operation for getting posix acls takes an inode
argument but various filesystems (e.g., 9p, cifs, overlayfs) need access
to the dentry. In contrast to the ->set_acl() inode operation we cannot
simply extend ->get_acl() to take a dentry argument. The ->get_acl()
inode operation is called from:

acl_permission_check()
-> check_acl()
   -> get_acl()

which is part of generic_permission() which in turn is part of
inode_permission(). Both generic_permission() and inode_permission() are
called in the ->permission() handler of various filesystems (e.g.,
overlayfs). So simply passing a dentry argument to ->get_acl() would
amount to also having to pass a dentry argument to ->permission(). We
should avoid this unnecessary change.

So instead of extending the existing inode operation rename it from
->get_acl() to ->get_inode_acl() and add a ->get_acl() method later that
passes a dentry argument and which filesystems that need access to the
dentry can implement instead of ->get_inode_acl(). Filesystems like cifs
which allow setting and getting posix acls but not using them for
permission checking during lookup can simply not implement
->get_inode_acl().

This is intended to be a non-functional change.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Suggested-by/Inspired-by: Christoph Hellwig 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

fs: pass dentry to set acl method

2022-10-19T10:55:42+00:00

The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

Since some filesystem rely on the dentry being available to them when
setting posix acls (e.g., 9p and cifs) they cannot rely on set acl inode
operation. But since ->set_acl() is required in order to use the generic
posix acl xattr handlers filesystems that do not implement this inode
operation cannot use the handler and need to implement their own
dedicated posix acl handlers.

Update the ->set_acl() inode method to take a dentry argument. This
allows all filesystems to rely on ->set_acl().

As far as I can tell all codepaths can be switched to rely on the dentry
instead of just the inode. Note that the original motivation for passing
the dentry separate from the inode instead of just the dentry in the
xattr handlers was because of security modules that call
security_d_instantiate(). This hook is called during
d_instantiate_new(), d_add(), __d_instantiate_anon(), and
d_splice_alias() to initialize the inode's security context and possibly
to set security.* xattrs. Since this only affects security.* xattrs this
is completely irrelevant for posix acls.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

mtd: always initialize 'stats' in struct mtd_oob_ops

2022-09-21T08:38:07+00:00

As the 'stats' field in struct mtd_oob_ops is used in conditional
expressions, ensure it is always zero-initialized in all such structures
to prevent random stack garbage from being interpreted as a pointer.

Strictly speaking, this problem currently only needs to be fixed for
struct mtd_oob_ops structures subsequently passed to mtd_read_oob().
However, this commit goes a step further and makes all instances of
struct mtd_oob_ops in the tree zero-initialized, in hope of preventing
future problems, e.g. if struct mtd_req_stats gets extended with write
statistics at some point.

Signed-off-by: Michał Kępień 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20220629125737.14418-3-kernel@kempniu.pl

Merge tag 'for-linus-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs

2022-06-03T21:42:24+00:00

Pull JFFS2, UBI and UBIFS updates from Richard Weinberger:
 "JFFS2:
   - Fixes for a memory leak

  UBI:
   - Fixes for fastmap (UAF, high CPU usage)

  UBIFS:
   - Minor cleanups"

* tag 'for-linus-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubi: ubi_create_volume: Fix use-after-free when volume creation failed
  ubi: fastmap: Check wl_pool for free peb before wear leveling
  ubi: fastmap: Fix high cpu usage of ubi_bgt by making sure wl_pool not empty
  ubifs: Use NULL instead of using plain integer as pointer
  ubifs: Simplify the return expression of run_gc()
  jffs2: fix memory leak in jffs2_do_fill_super
  jffs2: Use kzalloc instead of kmalloc/memset

jffs2: fix memory leak in jffs2_do_fill_super

2022-05-27T14:17:11+00:00

If jffs2_iget() or d_make_root() in jffs2_do_fill_super() returns
an error, we can observe the following kmemleak report:

--------------------------------------------
unreferenced object 0xffff888105a65340 (size 64):
  comm "mount", pid 710, jiffies 4302851558 (age 58.239s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [] kmem_cache_alloc_trace+0x475/0x8a0
    [] jffs2_sum_init+0x96/0x1a0
    [] jffs2_do_mount_fs+0x745/0x2120
    [] jffs2_do_fill_super+0x35c/0x810
    [] jffs2_fill_super+0x2b9/0x3b0
    [...]
unreferenced object 0xffff8881bd7f0000 (size 65536):
  comm "mount", pid 710, jiffies 4302851558 (age 58.239s)
  hex dump (first 32 bytes):
    bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb  ................
    bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb  ................
  backtrace:
    [] kmalloc_order+0xda/0x110
    [] kmalloc_order_trace+0x21/0x130
    [] __kmalloc+0x711/0x8a0
    [] jffs2_sum_init+0xd9/0x1a0
    [] jffs2_do_mount_fs+0x745/0x2120
    [] jffs2_do_fill_super+0x35c/0x810
    [] jffs2_fill_super+0x2b9/0x3b0
    [...]
--------------------------------------------

This is because the resources allocated in jffs2_sum_init() are not
released. Call jffs2_sum_exit() to release these resources to solve
the problem.

Fixes: e631ddba5887 ("[JFFS2] Add erase block summary support (mount time improvement)")
Signed-off-by: Baokun Li 
Signed-off-by: Richard Weinberger

jffs2: Use kzalloc instead of kmalloc/memset

2022-05-27T14:12:55+00:00

Use kzalloc rather than duplicating its implementation, which
makes code simple and easy to understand.

Signed-off-by: Haowen Bai 
[rw: Fixed printk string]
Signed-off-by: Richard Weinberger

fs: Change the type of filler_t

2022-05-09T20:36:48+00:00

By making filler_t the same as read_folio, we can use the same function
for both in gfs2.  We can push the use of folios down one more level
in jffs2 and nfs.  We also increase type safety for future users of the
various read_cache_page() family of functions by forcing the parameter
to be a pointer to struct file (or NULL).

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Andreas Gruenbacher

jffs2: Pass the file pointer to jffs2_do_readpage_unlock()

2022-05-09T20:28:41+00:00

In preparation for unifying the read_cache_page() and read_folio()
implementations, make jffs2_do_readpage_unlock() get the inode
from the page instead of passing it in from read_cache_page().

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Christoph Hellwig

jffs2: Convert jffs2 to read_folio

2022-05-09T20:21:45+00:00

This is a "weak" conversion which converts straight back to using pages.
A full conversion should be performed at some point, hopefully by
someone familiar with the filesystem.

Signed-off-by: Matthew Wilcox (Oracle)

fs: Remove flags parameter from aops->write_begin

2022-05-08T18:28:19+00:00

There are no more aop flags left, so remove the parameter.

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Christoph Hellwig