<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/fs/open.c, branch v6.11-rc3</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge tag 'vfs-6.11.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs</title>
<updated>2024-07-15T17:52:51+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-07-15T17:52:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b051320d6ab8cfdd77a48ef4e563584cd7681d2d'/>
<id>b051320d6ab8cfdd77a48ef4e563584cd7681d2d</id>
<content type='text'>
Pull misc vfs updates from Christian Brauner:
 "Features:

   - Support passing NULL along AT_EMPTY_PATH for statx().

     NULL paths with any flag value other than AT_EMPTY_PATH go the
     usual route and end up with -EFAULT to retain compatibility (Rust
     is abusing calls of the sort to detect availability of statx)

     This avoids path lookup code, lockref management, memory allocation
     and in case of NULL path userspace memory access (which can be
     quite expensive with SMAP on x86_64)

   - Don't block i_writecount during exec. Remove the
     deny_write_access() mechanism for executables

   - Relax open_by_handle_at() permissions in specific cases where we
     can prove that the caller had sufficient privileges to open a file

   - Switch timespec64 fields in struct inode to discrete integers
     freeing up 4 bytes

  Fixes:

   - Fix false positive circular locking warning in hfsplus

   - Initialize hfs_inode_info after hfs_alloc_inode() in hfs

   - Avoid accidental overflows in vfs_fallocate()

   - Don't interrupt fallocate with EINTR in tmpfs to avoid constantly
     restarting shmem_fallocate()

   - Add missing quote in comment in fs/readdir

  Cleanups:

   - Don't assign and test in an if statement in mqueue. Move the
     assignment out of the if statement

   - Reflow the logic in may_create_in_sticky()

   - Remove the usage of the deprecated ida_simple_xx() API from procfs

   - Reject FSCONFIG_CMD_CREATE_EXCL requets that depend on the new
     mount api early

   - Rename variables in copy_tree() to make it easier to understand

   - Replace WARN(down_read_trylock, ...) abuse with proper asserts in
     various places in the VFS

   - Get rid of user_path_at_empty() and drop the empty argument from
     getname_flags()

   - Check for error while copying and no path in one branch in
     getname_flags()

   - Avoid redundant smp_mb() for THP handling in do_dentry_open()

   - Rename parent_ino to d_parent_ino and make it use RCU

   - Remove unused header include in fs/readdir

   - Export in_group_capable() helper and switch f2fs and fuse over to
     it instead of open-coding the logic in both places"

* tag 'vfs-6.11.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits)
  ipc: mqueue: remove assignment from IS_ERR argument
  vfs: rename parent_ino to d_parent_ino and make it use RCU
  vfs: support statx(..., NULL, AT_EMPTY_PATH, ...)
  stat: use vfs_empty_path() helper
  fs: new helper vfs_empty_path()
  fs: reflow may_create_in_sticky()
  vfs: remove redundant smp_mb for thp handling in do_dentry_open
  fuse: Use in_group_or_capable() helper
  f2fs: Use in_group_or_capable() helper
  fs: Export in_group_or_capable()
  vfs: reorder checks in may_create_in_sticky
  hfs: fix to initialize fields of hfs_inode_info after hfs_alloc_inode()
  proc: Remove usage of the deprecated ida_simple_xx() API
  hfsplus: fix to avoid false alarm of circular locking
  Improve readability of copy_tree
  vfs: shave a branch in getname_flags
  vfs: retire user_path_at_empty and drop empty arg from getname_flags
  vfs: stop using user_path_at_empty in do_readlinkat
  tmpfs: don't interrupt fallocate with EINTR
  fs: don't block i_writecount during exec
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull misc vfs updates from Christian Brauner:
 "Features:

   - Support passing NULL along AT_EMPTY_PATH for statx().

     NULL paths with any flag value other than AT_EMPTY_PATH go the
     usual route and end up with -EFAULT to retain compatibility (Rust
     is abusing calls of the sort to detect availability of statx)

     This avoids path lookup code, lockref management, memory allocation
     and in case of NULL path userspace memory access (which can be
     quite expensive with SMAP on x86_64)

   - Don't block i_writecount during exec. Remove the
     deny_write_access() mechanism for executables

   - Relax open_by_handle_at() permissions in specific cases where we
     can prove that the caller had sufficient privileges to open a file

   - Switch timespec64 fields in struct inode to discrete integers
     freeing up 4 bytes

  Fixes:

   - Fix false positive circular locking warning in hfsplus

   - Initialize hfs_inode_info after hfs_alloc_inode() in hfs

   - Avoid accidental overflows in vfs_fallocate()

   - Don't interrupt fallocate with EINTR in tmpfs to avoid constantly
     restarting shmem_fallocate()

   - Add missing quote in comment in fs/readdir

  Cleanups:

   - Don't assign and test in an if statement in mqueue. Move the
     assignment out of the if statement

   - Reflow the logic in may_create_in_sticky()

   - Remove the usage of the deprecated ida_simple_xx() API from procfs

   - Reject FSCONFIG_CMD_CREATE_EXCL requets that depend on the new
     mount api early

   - Rename variables in copy_tree() to make it easier to understand

   - Replace WARN(down_read_trylock, ...) abuse with proper asserts in
     various places in the VFS

   - Get rid of user_path_at_empty() and drop the empty argument from
     getname_flags()

   - Check for error while copying and no path in one branch in
     getname_flags()

   - Avoid redundant smp_mb() for THP handling in do_dentry_open()

   - Rename parent_ino to d_parent_ino and make it use RCU

   - Remove unused header include in fs/readdir

   - Export in_group_capable() helper and switch f2fs and fuse over to
     it instead of open-coding the logic in both places"

* tag 'vfs-6.11.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits)
  ipc: mqueue: remove assignment from IS_ERR argument
  vfs: rename parent_ino to d_parent_ino and make it use RCU
  vfs: support statx(..., NULL, AT_EMPTY_PATH, ...)
  stat: use vfs_empty_path() helper
  fs: new helper vfs_empty_path()
  fs: reflow may_create_in_sticky()
  vfs: remove redundant smp_mb for thp handling in do_dentry_open
  fuse: Use in_group_or_capable() helper
  f2fs: Use in_group_or_capable() helper
  fs: Export in_group_or_capable()
  vfs: reorder checks in may_create_in_sticky
  hfs: fix to initialize fields of hfs_inode_info after hfs_alloc_inode()
  proc: Remove usage of the deprecated ida_simple_xx() API
  hfsplus: fix to avoid false alarm of circular locking
  Improve readability of copy_tree
  vfs: shave a branch in getname_flags
  vfs: retire user_path_at_empty and drop empty arg from getname_flags
  vfs: stop using user_path_at_empty in do_readlinkat
  tmpfs: don't interrupt fallocate with EINTR
  fs: don't block i_writecount during exec
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'vfs-6.10-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs</title>
<updated>2024-07-01T16:22:08+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-07-01T16:22:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9b458a260080961d5e766592b0394b08a12a0ba1'/>
<id>9b458a260080961d5e766592b0394b08a12a0ba1</id>
<content type='text'>
Pull vfs fixes from Christian Brauner:
 "Misc:

   - Don't misleadingly warn during filesystem thaw operations.

     It's possible that a block device which was frozen before it was
     mounted can cause a failing thaw operation if someone concurrently
     tried to mount it while that thaw operation was issued and the
     device had already been temporarily claimed for the mount (The
     mount will of course be aborted because the device is frozen).

  netfs:

   - Fix io_uring based write-through. Make sure that the total request
     length is correctly set.

   - Fix partial writes to folio tail.

   - Remove some xarray helpers that were intended for bounce buffers
     which got defered to a later patch series.

   - Make netfs_page_mkwrite() whether folio-&gt;mapping is vallid after
     acquiring the folio lock.

   - Make netfs_page_mkrite() flush conflicting data instead of waiting.

  fsnotify:

   - Ensure that fsnotify creation events are generated before fsnotify
     open events when a file is created via -&gt;atomic_open(). The
     ordering was broken before.

   - Ensure that no fsnotify events are generated for O_PATH file
     descriptors. While no fsnotify open events were generated, fsnotify
     close events were. Make it consistent and don't produce any"

* tag 'vfs-6.10-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  netfs: Fix netfs_page_mkwrite() to flush conflicting data, not wait
  netfs: Fix netfs_page_mkwrite() to check folio-&gt;mapping is valid
  netfs: Delete some xarray-wangling functions that aren't used
  netfs: Fix early issue of write op on partial write to folio tail
  netfs: Fix io_uring based write-through
  vfs: generate FS_CREATE before FS_OPEN when -&gt;atomic_open used.
  fsnotify: Do not generate events for O_PATH file descriptors
  fs: don't misleadingly warn during thaw operations
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull vfs fixes from Christian Brauner:
 "Misc:

   - Don't misleadingly warn during filesystem thaw operations.

     It's possible that a block device which was frozen before it was
     mounted can cause a failing thaw operation if someone concurrently
     tried to mount it while that thaw operation was issued and the
     device had already been temporarily claimed for the mount (The
     mount will of course be aborted because the device is frozen).

  netfs:

   - Fix io_uring based write-through. Make sure that the total request
     length is correctly set.

   - Fix partial writes to folio tail.

   - Remove some xarray helpers that were intended for bounce buffers
     which got defered to a later patch series.

   - Make netfs_page_mkwrite() whether folio-&gt;mapping is vallid after
     acquiring the folio lock.

   - Make netfs_page_mkrite() flush conflicting data instead of waiting.

  fsnotify:

   - Ensure that fsnotify creation events are generated before fsnotify
     open events when a file is created via -&gt;atomic_open(). The
     ordering was broken before.

   - Ensure that no fsnotify events are generated for O_PATH file
     descriptors. While no fsnotify open events were generated, fsnotify
     close events were. Make it consistent and don't produce any"

* tag 'vfs-6.10-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  netfs: Fix netfs_page_mkwrite() to flush conflicting data, not wait
  netfs: Fix netfs_page_mkwrite() to check folio-&gt;mapping is valid
  netfs: Delete some xarray-wangling functions that aren't used
  netfs: Fix early issue of write op on partial write to folio tail
  netfs: Fix io_uring based write-through
  vfs: generate FS_CREATE before FS_OPEN when -&gt;atomic_open used.
  fsnotify: Do not generate events for O_PATH file descriptors
  fs: don't misleadingly warn during thaw operations
</pre>
</div>
</content>
</entry>
<entry>
<title>vfs: remove redundant smp_mb for thp handling in do_dentry_open</title>
<updated>2024-06-25T09:15:48+00:00</updated>
<author>
<name>Mateusz Guzik</name>
<email>mjguzik@gmail.com</email>
</author>
<published>2024-06-24T08:54:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8e3447822d7d8c0f562c6851a7a31e24d1ede55e'/>
<id>8e3447822d7d8c0f562c6851a7a31e24d1ede55e</id>
<content type='text'>
opening for write performs:

if (f-&gt;f_mode &amp; FMODE_WRITE) {
[snip]
        smp_mb();
        if (filemap_nr_thps(inode-&gt;i_mapping)) {
[snip]
        }
}

filemap_nr_thps on kernels built without CONFIG_READ_ONLY_THP_FOR
expands to 0, allowing the compiler to eliminate the entire thing, with
exception of the fence (and the branch leading there).

So happens required synchronisation between i_writecount and nr_thps
changes is already provided by the full fence coming from
get_write_access -&gt; atomic_inc_unless_negative, thus the smp_mb instance
above can be removed regardless of CONFIG_READ_ONLY_THP_FOR.

While I updated commentary in places claiming to match the now-removed
fence, I did not try to patch them to act on the compile option.

I did not bother benchmarking it, not issuing a spurious full fence in
the fast path does not warrant justification from perf standpoint.

Signed-off-by: Mateusz Guzik &lt;mjguzik@gmail.com&gt;
Link: https://lore.kernel.org/r/20240624085402.493630-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
opening for write performs:

if (f-&gt;f_mode &amp; FMODE_WRITE) {
[snip]
        smp_mb();
        if (filemap_nr_thps(inode-&gt;i_mapping)) {
[snip]
        }
}

filemap_nr_thps on kernels built without CONFIG_READ_ONLY_THP_FOR
expands to 0, allowing the compiler to eliminate the entire thing, with
exception of the fence (and the branch leading there).

So happens required synchronisation between i_writecount and nr_thps
changes is already provided by the full fence coming from
get_write_access -&gt; atomic_inc_unless_negative, thus the smp_mb instance
above can be removed regardless of CONFIG_READ_ONLY_THP_FOR.

While I updated commentary in places claiming to match the now-removed
fence, I did not try to patch them to act on the compile option.

I did not bother benchmarking it, not issuing a spurious full fence in
the fast path does not warrant justification from perf standpoint.

Signed-off-by: Mateusz Guzik &lt;mjguzik@gmail.com&gt;
Link: https://lore.kernel.org/r/20240624085402.493630-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ftruncate: pass a signed offset</title>
<updated>2024-06-24T16:29:20+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2024-06-19T09:34:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4b8e88e563b5f666446d002ad0dc1e6e8e7102b0'/>
<id>4b8e88e563b5f666446d002ad0dc1e6e8e7102b0</id>
<content type='text'>
The old ftruncate() syscall, using the 32-bit off_t misses a sign
extension when called in compat mode on 64-bit architectures.  As a
result, passing a negative length accidentally succeeds in truncating
to file size between 2GiB and 4GiB.

Changing the type of the compat syscall to the signed compat_off_t
changes the behavior so it instead returns -EINVAL.

The native entry point, the truncate() syscall and the corresponding
loff_t based variants are all correct already and do not suffer
from this mistake.

Fixes: 3f6d078d4acc ("fix compat truncate/ftruncate")
Reviewed-by: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The old ftruncate() syscall, using the 32-bit off_t misses a sign
extension when called in compat mode on 64-bit architectures.  As a
result, passing a negative length accidentally succeeds in truncating
to file size between 2GiB and 4GiB.

Changing the type of the compat syscall to the signed compat_off_t
changes the behavior so it instead returns -EINVAL.

The native entry point, the truncate() syscall and the corresponding
loff_t based variants are all correct already and do not suffer
from this mistake.

Fixes: 3f6d078d4acc ("fix compat truncate/ftruncate")
Reviewed-by: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>vfs: generate FS_CREATE before FS_OPEN when -&gt;atomic_open used.</title>
<updated>2024-06-18T14:26:09+00:00</updated>
<author>
<name>NeilBrown</name>
<email>neilb@suse.de</email>
</author>
<published>2024-06-17T16:23:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7d1cf5e624ef5d81b933e8b7f4927531166c0f7a'/>
<id>7d1cf5e624ef5d81b933e8b7f4927531166c0f7a</id>
<content type='text'>
When a file is opened and created with open(..., O_CREAT) we get
both the CREATE and OPEN fsnotify events and would expect them in that
order.   For most filesystems we get them in that order because
open_last_lookups() calls fsnofify_create() and then do_open() (from
path_openat()) calls vfs_open()-&gt;do_dentry_open() which calls
fsnotify_open().

However when -&gt;atomic_open is used, the
   do_dentry_open() -&gt; fsnotify_open()
call happens from finish_open() which is called from the -&gt;atomic_open
handler in lookup_open() which is called *before* open_last_lookups()
calls fsnotify_create.  So we get the "open" notification before
"create" - which is backwards.  ltp testcase inotify02 tests this and
reports the inconsistency.

This patch lifts the fsnotify_open() call out of do_dentry_open() and
places it higher up the call stack.  There are three callers of
do_dentry_open().

For vfs_open() and kernel_file_open() the fsnotify_open() is placed
directly in that caller so there should be no behavioural change.

For finish_open() there are two cases:
 - finish_open is used in -&gt;atomic_open handlers.  For these we add a
   call to fsnotify_open() at open_last_lookups() if FMODE_OPENED is
   set - which means do_dentry_open() has been called.
 - finish_open is used in -&gt;tmpfile() handlers.  For these a similar
   call to fsnotify_open() is added to vfs_tmpfile()

With this patch NFSv3 is restored to its previous behaviour (before
-&gt;atomic_open support was added) of generating CREATE notifications
before OPEN, and NFSv4 now has that same correct ordering that is has
not had before.  I haven't tested other filesystems.

Fixes: 7c6c5249f061 ("NFS: add atomic_open for NFSv3 to handle O_TRUNC correctly.")
Reported-by: James Clark &lt;james.clark@arm.com&gt;
Closes: https://lore.kernel.org/all/01c3bf2e-eb1f-4b7f-a54f-d2a05dd3d8c8@arm.com
Signed-off-by: NeilBrown &lt;neilb@suse.de&gt;
Link: https://lore.kernel.org/r/171817619547.14261.975798725161704336@noble.neil.brown.name
Fixes: 7b8c9d7bb457 ("fsnotify: move fsnotify_open() hook into do_dentry_open()")
Tested-by: James Clark &lt;james.clark@arm.com&gt;
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
Link: https://lore.kernel.org/r/20240617162303.1596-2-jack@suse.cz
Reviewed-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When a file is opened and created with open(..., O_CREAT) we get
both the CREATE and OPEN fsnotify events and would expect them in that
order.   For most filesystems we get them in that order because
open_last_lookups() calls fsnofify_create() and then do_open() (from
path_openat()) calls vfs_open()-&gt;do_dentry_open() which calls
fsnotify_open().

However when -&gt;atomic_open is used, the
   do_dentry_open() -&gt; fsnotify_open()
call happens from finish_open() which is called from the -&gt;atomic_open
handler in lookup_open() which is called *before* open_last_lookups()
calls fsnotify_create.  So we get the "open" notification before
"create" - which is backwards.  ltp testcase inotify02 tests this and
reports the inconsistency.

This patch lifts the fsnotify_open() call out of do_dentry_open() and
places it higher up the call stack.  There are three callers of
do_dentry_open().

For vfs_open() and kernel_file_open() the fsnotify_open() is placed
directly in that caller so there should be no behavioural change.

For finish_open() there are two cases:
 - finish_open is used in -&gt;atomic_open handlers.  For these we add a
   call to fsnotify_open() at open_last_lookups() if FMODE_OPENED is
   set - which means do_dentry_open() has been called.
 - finish_open is used in -&gt;tmpfile() handlers.  For these a similar
   call to fsnotify_open() is added to vfs_tmpfile()

With this patch NFSv3 is restored to its previous behaviour (before
-&gt;atomic_open support was added) of generating CREATE notifications
before OPEN, and NFSv4 now has that same correct ordering that is has
not had before.  I haven't tested other filesystems.

Fixes: 7c6c5249f061 ("NFS: add atomic_open for NFSv3 to handle O_TRUNC correctly.")
Reported-by: James Clark &lt;james.clark@arm.com&gt;
Closes: https://lore.kernel.org/all/01c3bf2e-eb1f-4b7f-a54f-d2a05dd3d8c8@arm.com
Signed-off-by: NeilBrown &lt;neilb@suse.de&gt;
Link: https://lore.kernel.org/r/171817619547.14261.975798725161704336@noble.neil.brown.name
Fixes: 7b8c9d7bb457 ("fsnotify: move fsnotify_open() hook into do_dentry_open()")
Tested-by: James Clark &lt;james.clark@arm.com&gt;
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
Link: https://lore.kernel.org/r/20240617162303.1596-2-jack@suse.cz
Reviewed-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fs: remove accidental overflow during wraparound check</title>
<updated>2024-05-27T13:58:46+00:00</updated>
<author>
<name>Justin Stitt</name>
<email>justinstitt@google.com</email>
</author>
<published>2024-05-13T17:50:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=23cc6ef6fd453b13502caae23130844e7d6ed0fe'/>
<id>23cc6ef6fd453b13502caae23130844e7d6ed0fe</id>
<content type='text'>
Running syzkaller with the newly enabled signed integer overflow
sanitizer produces this report:

[  195.401651] ------------[ cut here ]------------
[  195.404808] UBSAN: signed-integer-overflow in ../fs/open.c:321:15
[  195.408739] 9223372036854775807 + 562984447377399 cannot be represented in type 'loff_t' (aka 'long long')
[  195.414683] CPU: 1 PID: 703 Comm: syz-executor.0 Not tainted 6.8.0-rc2-00039-g14de58dbe653-dirty #11
[  195.420138] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[  195.425804] Call Trace:
[  195.427360]  &lt;TASK&gt;
[  195.428791]  dump_stack_lvl+0x93/0xd0
[  195.431150]  handle_overflow+0x171/0x1b0
[  195.433640]  vfs_fallocate+0x459/0x4f0
...
[  195.490053] ------------[ cut here ]------------
[  195.493146] UBSAN: signed-integer-overflow in ../fs/open.c:321:61
[  195.497030] 9223372036854775807 + 562984447377399 cannot be represented in type 'loff_t' (aka 'long long)
[  195.502940] CPU: 1 PID: 703 Comm: syz-executor.0 Not tainted 6.8.0-rc2-00039-g14de58dbe653-dirty #11
[  195.508395] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[  195.514075] Call Trace:
[  195.515636]  &lt;TASK&gt;
[  195.517000]  dump_stack_lvl+0x93/0xd0
[  195.519255]  handle_overflow+0x171/0x1b0
[  195.521677]  vfs_fallocate+0x4cb/0x4f0
[  195.524033]  __x64_sys_fallocate+0xb2/0xf0

Historically, the signed integer overflow sanitizer did not work in the
kernel due to its interaction with `-fwrapv` but this has since been
changed [1] in the newest version of Clang. It was re-enabled in the
kernel with Commit 557f8c582a9ba8ab ("ubsan: Reintroduce signed overflow
sanitizer").

Let's use the check_add_overflow helper to first verify the addition
stays within the bounds of its type (long long); then we can use that
sum for the following check.

Link: https://github.com/llvm/llvm-project/pull/82432 [1]
Closes: https://github.com/KSPP/linux/issues/356
Cc: linux-hardening@vger.kernel.org
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Justin Stitt &lt;justinstitt@google.com&gt;
Link: https://lore.kernel.org/r/20240513-b4-sio-vfs_fallocate-v2-1-db415872fb16@google.com
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Running syzkaller with the newly enabled signed integer overflow
sanitizer produces this report:

[  195.401651] ------------[ cut here ]------------
[  195.404808] UBSAN: signed-integer-overflow in ../fs/open.c:321:15
[  195.408739] 9223372036854775807 + 562984447377399 cannot be represented in type 'loff_t' (aka 'long long')
[  195.414683] CPU: 1 PID: 703 Comm: syz-executor.0 Not tainted 6.8.0-rc2-00039-g14de58dbe653-dirty #11
[  195.420138] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[  195.425804] Call Trace:
[  195.427360]  &lt;TASK&gt;
[  195.428791]  dump_stack_lvl+0x93/0xd0
[  195.431150]  handle_overflow+0x171/0x1b0
[  195.433640]  vfs_fallocate+0x459/0x4f0
...
[  195.490053] ------------[ cut here ]------------
[  195.493146] UBSAN: signed-integer-overflow in ../fs/open.c:321:61
[  195.497030] 9223372036854775807 + 562984447377399 cannot be represented in type 'loff_t' (aka 'long long)
[  195.502940] CPU: 1 PID: 703 Comm: syz-executor.0 Not tainted 6.8.0-rc2-00039-g14de58dbe653-dirty #11
[  195.508395] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[  195.514075] Call Trace:
[  195.515636]  &lt;TASK&gt;
[  195.517000]  dump_stack_lvl+0x93/0xd0
[  195.519255]  handle_overflow+0x171/0x1b0
[  195.521677]  vfs_fallocate+0x4cb/0x4f0
[  195.524033]  __x64_sys_fallocate+0xb2/0xf0

Historically, the signed integer overflow sanitizer did not work in the
kernel due to its interaction with `-fwrapv` but this has since been
changed [1] in the newest version of Clang. It was re-enabled in the
kernel with Commit 557f8c582a9ba8ab ("ubsan: Reintroduce signed overflow
sanitizer").

Let's use the check_add_overflow helper to first verify the addition
stays within the bounds of its type (long long); then we can use that
sum for the following check.

Link: https://github.com/llvm/llvm-project/pull/82432 [1]
Closes: https://github.com/KSPP/linux/issues/356
Cc: linux-hardening@vger.kernel.org
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Justin Stitt &lt;justinstitt@google.com&gt;
Link: https://lore.kernel.org/r/20240513-b4-sio-vfs_fallocate-v2-1-db415872fb16@google.com
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt;
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>do_dentry_open(): kill inode argument</title>
<updated>2024-04-15T20:03:25+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2024-01-20T11:28:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=0f4a2cebe256dab4e9b8836b87ce4c909cd585eb'/>
<id>0f4a2cebe256dab4e9b8836b87ce4c909cd585eb</id>
<content type='text'>
should've been done as soon as overlayfs stopped messing with fake
paths...

Reviewed-by: Christian Brauner &lt;brauner@kernel.org&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
should've been done as soon as overlayfs stopped messing with fake
paths...

Reviewed-by: Christian Brauner &lt;brauner@kernel.org&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kernel_file_open(): get rid of inode argument</title>
<updated>2024-04-15T20:03:24+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2024-01-20T11:24:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=af58dc1f50c1946018773beca23ebaad587b9cc9'/>
<id>af58dc1f50c1946018773beca23ebaad587b9cc9</id>
<content type='text'>
always equal to -&gt;dentry-&gt;d_inode of the path argument these
days.

Reviewed-by: Christian Brauner &lt;brauner@kernel.org&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
always equal to -&gt;dentry-&gt;d_inode of the path argument these
days.

Reviewed-by: Christian Brauner &lt;brauner@kernel.org&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'lsm-pr-20240312' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm</title>
<updated>2024-03-13T03:03:34+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-03-13T03:03:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=cc4a875cf3b3bc07d523ea85b8ca45da1ca4f4e6'/>
<id>cc4a875cf3b3bc07d523ea85b8ca45da1ca4f4e6</id>
<content type='text'>
Pull lsm updates from Paul Moore:

 - Promote IMA/EVM to a proper LSM

   This is the bulk of the diffstat, and the source of all the changes
   in the VFS code. Prior to the start of the LSM stacking work it was
   important that IMA/EVM were separate from the rest of the LSMs,
   complete with their own hooks, infrastructure, etc. as it was the
   only way to enable IMA/EVM at the same time as a LSM.

   However, now that the bulk of the LSM infrastructure supports
   multiple simultaneous LSMs, we can simplify things greatly by
   bringing IMA/EVM into the LSM infrastructure as proper LSMs. This is
   something I've wanted to see happen for quite some time and Roberto
   was kind enough to put in the work to make it happen.

 - Use the LSM hook default values to simplify the call_int_hook() macro

   Previously the call_int_hook() macro required callers to supply a
   default return value, despite a default value being specified when
   the LSM hook was defined.

   This simplifies the macro by using the defined default return value
   which makes life easier for callers and should also reduce the number
   of return value bugs in the future (we've had a few pop up recently,
   hence this work).

 - Use the KMEM_CACHE() macro instead of kmem_cache_create()

   The guidance appears to be to use the KMEM_CACHE() macro when
   possible and there is no reason why we can't use the macro, so let's
   use it.

 - Fix a number of comment typos in the LSM hook comment blocks

   Not much to say here, we fixed some questionable grammar decisions in
   the LSM hook comment blocks.

* tag 'lsm-pr-20240312' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (28 commits)
  cred: Use KMEM_CACHE() instead of kmem_cache_create()
  lsm: use default hook return value in call_int_hook()
  lsm: fix typos in security/security.c comment headers
  integrity: Remove LSM
  ima: Make it independent from 'integrity' LSM
  evm: Make it independent from 'integrity' LSM
  evm: Move to LSM infrastructure
  ima: Move IMA-Appraisal to LSM infrastructure
  ima: Move to LSM infrastructure
  integrity: Move integrity_kernel_module_request() to IMA
  security: Introduce key_post_create_or_update hook
  security: Introduce inode_post_remove_acl hook
  security: Introduce inode_post_set_acl hook
  security: Introduce inode_post_create_tmpfile hook
  security: Introduce path_post_mknod hook
  security: Introduce file_release hook
  security: Introduce file_post_open hook
  security: Introduce inode_post_removexattr hook
  security: Introduce inode_post_setattr hook
  security: Align inode_setattr hook definition with EVM
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull lsm updates from Paul Moore:

 - Promote IMA/EVM to a proper LSM

   This is the bulk of the diffstat, and the source of all the changes
   in the VFS code. Prior to the start of the LSM stacking work it was
   important that IMA/EVM were separate from the rest of the LSMs,
   complete with their own hooks, infrastructure, etc. as it was the
   only way to enable IMA/EVM at the same time as a LSM.

   However, now that the bulk of the LSM infrastructure supports
   multiple simultaneous LSMs, we can simplify things greatly by
   bringing IMA/EVM into the LSM infrastructure as proper LSMs. This is
   something I've wanted to see happen for quite some time and Roberto
   was kind enough to put in the work to make it happen.

 - Use the LSM hook default values to simplify the call_int_hook() macro

   Previously the call_int_hook() macro required callers to supply a
   default return value, despite a default value being specified when
   the LSM hook was defined.

   This simplifies the macro by using the defined default return value
   which makes life easier for callers and should also reduce the number
   of return value bugs in the future (we've had a few pop up recently,
   hence this work).

 - Use the KMEM_CACHE() macro instead of kmem_cache_create()

   The guidance appears to be to use the KMEM_CACHE() macro when
   possible and there is no reason why we can't use the macro, so let's
   use it.

 - Fix a number of comment typos in the LSM hook comment blocks

   Not much to say here, we fixed some questionable grammar decisions in
   the LSM hook comment blocks.

* tag 'lsm-pr-20240312' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (28 commits)
  cred: Use KMEM_CACHE() instead of kmem_cache_create()
  lsm: use default hook return value in call_int_hook()
  lsm: fix typos in security/security.c comment headers
  integrity: Remove LSM
  ima: Make it independent from 'integrity' LSM
  evm: Make it independent from 'integrity' LSM
  evm: Move to LSM infrastructure
  ima: Move IMA-Appraisal to LSM infrastructure
  ima: Move to LSM infrastructure
  integrity: Move integrity_kernel_module_request() to IMA
  security: Introduce key_post_create_or_update hook
  security: Introduce inode_post_remove_acl hook
  security: Introduce inode_post_set_acl hook
  security: Introduce inode_post_create_tmpfile hook
  security: Introduce path_post_mknod hook
  security: Introduce file_release hook
  security: Introduce file_post_open hook
  security: Introduce inode_post_removexattr hook
  security: Introduce inode_post_setattr hook
  security: Align inode_setattr hook definition with EVM
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-6.9/io_uring-20240310' of git://git.kernel.dk/linux</title>
<updated>2024-03-11T18:35:31+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-03-11T18:35:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d2c84bdce25a678c1e1f116d65b58790bd241af0'/>
<id>d2c84bdce25a678c1e1f116d65b58790bd241af0</id>
<content type='text'>
Pull io_uring updates from Jens Axboe:

 - Make running of task_work internal loops more fair, and unify how the
   different methods deal with them (me)

 - Support for per-ring NAPI. The two minor networking patches are in a
   shared branch with netdev (Stefan)

 - Add support for truncate (Tony)

 - Export SQPOLL utilization stats (Xiaobing)

 - Multishot fixes (Pavel)

 - Fix for a race in manipulating the request flags via poll (Pavel)

 - Cleanup the multishot checking by making it generic, moving it out of
   opcode handlers (Pavel)

 - Various tweaks and cleanups (me, Kunwu, Alexander)

* tag 'for-6.9/io_uring-20240310' of git://git.kernel.dk/linux: (53 commits)
  io_uring: Fix sqpoll utilization check racing with dying sqpoll
  io_uring/net: dedup io_recv_finish req completion
  io_uring: refactor DEFER_TASKRUN multishot checks
  io_uring: fix mshot io-wq checks
  io_uring/net: add io_req_msg_cleanup() helper
  io_uring/net: simplify msghd-&gt;msg_inq checking
  io_uring/kbuf: rename REQ_F_PARTIAL_IO to REQ_F_BL_NO_RECYCLE
  io_uring/net: remove dependency on REQ_F_PARTIAL_IO for sr-&gt;done_io
  io_uring/net: correctly handle multishot recvmsg retry setup
  io_uring/net: clear REQ_F_BL_EMPTY in the multishot retry handler
  io_uring: fix io_queue_proc modifying req-&gt;flags
  io_uring: fix mshot read defer taskrun cqe posting
  io_uring/net: fix overflow check in io_recvmsg_mshot_prep()
  io_uring/net: correct the type of variable
  io_uring/sqpoll: statistics of the true utilization of sq threads
  io_uring/net: move recv/recvmsg flags out of retry loop
  io_uring/kbuf: flag request if buffer pool is empty after buffer pick
  io_uring/net: improve the usercopy for sendmsg/recvmsg
  io_uring/net: move receive multishot out of the generic msghdr path
  io_uring/net: unify how recvmsg and sendmsg copy in the msghdr
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull io_uring updates from Jens Axboe:

 - Make running of task_work internal loops more fair, and unify how the
   different methods deal with them (me)

 - Support for per-ring NAPI. The two minor networking patches are in a
   shared branch with netdev (Stefan)

 - Add support for truncate (Tony)

 - Export SQPOLL utilization stats (Xiaobing)

 - Multishot fixes (Pavel)

 - Fix for a race in manipulating the request flags via poll (Pavel)

 - Cleanup the multishot checking by making it generic, moving it out of
   opcode handlers (Pavel)

 - Various tweaks and cleanups (me, Kunwu, Alexander)

* tag 'for-6.9/io_uring-20240310' of git://git.kernel.dk/linux: (53 commits)
  io_uring: Fix sqpoll utilization check racing with dying sqpoll
  io_uring/net: dedup io_recv_finish req completion
  io_uring: refactor DEFER_TASKRUN multishot checks
  io_uring: fix mshot io-wq checks
  io_uring/net: add io_req_msg_cleanup() helper
  io_uring/net: simplify msghd-&gt;msg_inq checking
  io_uring/kbuf: rename REQ_F_PARTIAL_IO to REQ_F_BL_NO_RECYCLE
  io_uring/net: remove dependency on REQ_F_PARTIAL_IO for sr-&gt;done_io
  io_uring/net: correctly handle multishot recvmsg retry setup
  io_uring/net: clear REQ_F_BL_EMPTY in the multishot retry handler
  io_uring: fix io_queue_proc modifying req-&gt;flags
  io_uring: fix mshot read defer taskrun cqe posting
  io_uring/net: fix overflow check in io_recvmsg_mshot_prep()
  io_uring/net: correct the type of variable
  io_uring/sqpoll: statistics of the true utilization of sq threads
  io_uring/net: move recv/recvmsg flags out of retry loop
  io_uring/kbuf: flag request if buffer pool is empty after buffer pick
  io_uring/net: improve the usercopy for sendmsg/recvmsg
  io_uring/net: move receive multishot out of the generic msghdr path
  io_uring/net: unify how recvmsg and sendmsg copy in the msghdr
  ...
</pre>
</div>
</content>
</entry>
</feed>
