linux-stable.git/fs/debugfs/inode.c, branch v5.10.78

debugfs: debugfs_create_file_size(): use IS_ERR to check for error

2021-10-06T13:55:59+00:00

commit af505cad9567f7a500d34bf183696d570d7f6810 upstream.

debugfs_create_file() returns encoded error so use IS_ERR for checking
return value.

Reviewed-by: Christian König 
Signed-off-by: Nirmoy Das 
Fixes: ff9fb72bc077 ("debugfs: return error values, not NULL")
Cc: stable 
References: https://gitlab.freedesktop.org/drm/amd/-/issues/1686
Link: https://lore.kernel.org/r/20210902102917.2233-1-nirmoy.das@amd.com
Signed-off-by: Greg Kroah-Hartman

debugfs: Make debugfs_allow RO after init

2021-05-19T08:13:19+00:00

commit 312723a0b34d6d110aa4427a982536bb36ab8471 upstream.

Since debugfs_allow is only set at boot time during __init, make it
read-only after being set.

Fixes: a24c6f7bc923 ("debugfs: Add access restriction option")
Cc: Peter Enderborg 
Reviewed-by: Peter Enderborg 
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/20210405213959.3079432-1-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman

debugfs: do not attempt to create a new file before the filesystem is initalized

2021-03-04T10:37:17+00:00

commit 56348560d495d2501e87db559a61de717cd3ab02 upstream.

Some subsystems want to add debugfs files at early boot, way before
debugfs is initialized.  This seems to work somehow as the vfs layer
will not allow it to happen, but let's be explicit and test to ensure we
are properly up and running before allowing files to be created.

Cc: "Rafael J. Wysocki" 
Cc: stable 
Reported-by: Michael Walle 
Reported-by: Marc Zyngier 
Link: https://lore.kernel.org/r/20210218100818.3622317-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

debugfs: be more robust at handling improper input in debugfs_lookup()

2021-03-04T10:37:17+00:00

commit bc6de804d36b3709d54fa22bd128cbac91c11526 upstream.

debugfs_lookup() doesn't like it if it is passed an illegal name
pointer, or if the filesystem isn't even initialized yet.  If either of
these happen, it will crash the system, so fix it up by properly testing
for valid input and that we are up and running before trying to find a
file in the filesystem.

Cc: "Rafael J. Wysocki" 
Cc: stable 
Reported-by: Michael Walle 
Tested-by: Michael Walle 
Tested-by: Marc Zyngier 
Link: https://lore.kernel.org/r/20210218100818.3622317-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

debugfs: Add access restriction option

2020-07-23T15:10:25+00:00

Since debugfs include sensitive information it need to be treated
carefully. But it also has many very useful debug functions for userspace.
With this option we can have same configuration for system with
need of debugfs and a way to turn it off. This gives a extra protection
for exposure on systems where user-space services with system
access are attacked.

It is controlled by a configurable default value that can be override
with a kernel command line parameter. (debugfs=)

It can be on or off, but also internally on but not seen from user-space.
This no-mount mode do not register a debugfs as filesystem, but client can
register their parts in the internal structures. This data can be readed
with a debugger or saved with a crashkernel. When it is off clients
get EPERM error when accessing the functions for registering their
components.

Signed-off-by: Peter Enderborg 
Link: https://lore.kernel.org/r/20200716071511.26864-3-peter.enderborg@sony.com
Signed-off-by: Greg Kroah-Hartman

debugfs: remove return value of debugfs_create_file_size()

2020-03-18T12:35:29+00:00

No one checks the return value of debugfs_create_file_size, as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Signed-off-by: Greg Kroah-Hartman 
Link: https://lore.kernel.org/r/20200309163640.237984-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

Merge branch 'work.recursive_removal' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2020-02-05T05:09:46+00:00

Pull vfs recursive removal updates from Al Viro:
 "We have quite a few places where synthetic filesystems do an
  equivalent of 'rm -rf', with varying amounts of code duplication,
  wrong locking, etc. That really ought to be a library helper.

  Only debugfs (and very similar tracefs) are converted here - I have
  more conversions, but they'd never been in -next, so they'll have to
  wait"

* 'work.recursive_removal' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  simple_recursive_removal(): kernel-side rm -rf for ramfs-style filesystems

debugfs: Fix warnings when building documentation

2020-01-06T19:35:37+00:00

Fix the following warnings:

fs/debugfs/inode.c:423: WARNING: Inline literal start-string without end-string.
fs/debugfs/inode.c:502: WARNING: Inline literal start-string without end-string.
fs/debugfs/inode.c:534: WARNING: Inline literal start-string without end-string.
fs/debugfs/inode.c:627: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:496: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:502: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:581: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:587: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:846: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:852: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:899: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:905: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:1091: WARNING: Inline literal start-string without end-string.
fs/debugfs/file.c:1097: WARNING: Inline literal start-string without end-string

By replacing %ERR_PTR with ERR_PTR.

Signed-off-by: Daniel W. S. Almeida 
Link: https://lore.kernel.org/r/20191227010035.854913-1-dwlsalmeida@gmail.com
Signed-off-by: Greg Kroah-Hartman

simple_recursive_removal(): kernel-side rm -rf for ramfs-style filesystems

2019-12-11T03:29:58+00:00

two requirements: no file creations in IS_DEADDIR and no cross-directory
renames whatsoever.

Signed-off-by: Al Viro

new helper: lookup_positive_unlocked()

2019-11-15T18:49:04+00:00

Most of the callers of lookup_one_len_unlocked() treat negatives are
ERR_PTR(-ENOENT).  Provide a helper that would do just that.  Note
that a pinned positive dentry remains positive - it's ->d_inode is
stable, etc.; a pinned _negative_ dentry can become positive at any
point as long as you are not holding its parent at least shared.
So using lookup_one_len_unlocked() needs to be careful;
lookup_positive_unlocked() is safer and that's what the callers
end up open-coding anyway.

Signed-off-by: Al Viro