linux.git/fs/sysfs/file.c, branch v3.11

sysfs_notify is only possible on file attributes

2013-06-07T23:05:50+00:00

If sysfs_notify is called on a binary attribute, bad things can
happen, so prevent it.

Note, no in-kernel usage of this is currently present, but in the
future, it's good to be safe.

Changes in V2:
- Also ignore sysfs_notify on dirs, links
- Use WARN_ON rather than silently failing
- Compiled and tested (huge apologies about first submission)

Signed-off-by: Nick Dyer 
Signed-off-by: Greg Kroah-Hartman

sysfs: Mark sysfs_attr_ns static

2012-11-27T00:25:36+00:00

Nothing outside of fs/sysfs/file.c references this function, so mark it static.

Signed-off-by: Josh Triplett 
Signed-off-by: Greg Kroah-Hartman

sysfs: Complain bitterly about attempts to remove files from nonexistent directories.

2012-01-24T20:12:32+00:00

Recently an OOPS was observed from the usb serial io_ti driver when it tried to remove
sysfs directories.  Upon investigation it turns out this driver was always buggy
and that a recent sysfs change had stopped guarding itself against removing attributes
from sysfs directories that had already been removed. :(

Historically we have been silent about attempting to files from nonexistent sysfs
directories and have politely returned error codes.  That has resulted in people writing
broken code that ignores the error codes.

Issue a kernel WARNING and a stack backtrace to make it clear in no uncertain
terms that abusing sysfs is not ok, and the callers need to fix their code.

This change transforms the io_ti OOPS into a more comprehensible error message
and stack backtrace.

Signed-off-by: Eric W. Biederman 
Reported-by: Wolfgang Frisch 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

sysfs: propagate umode_t

2012-01-04T03:55:03+00:00

Signed-off-by: Al Viro

switch sysfs_chmod_file() to umode_t

2012-01-04T03:54:56+00:00

Signed-off-by: Al Viro

sysfs: Reject with a warning invalid uses of tagged directories.

2011-10-19T23:24:16+00:00

sysfs is a core piece of ifrastructure that many people use and
few people have all of the rules in their head on how to use
it correctly.  Add warnings for people using tagged directories
improperly to that any misuses can be caught and diagnosed quickly.

A single inexpensive test in sysfs_find_dirent is almost sufficient
to catch all possible misuses.  An additional warning is needed
in sysfs_add_dirent so that we actually fail when attempting to
add an untagged dirent in a tagged directory.

Signed-off-by: Eric W. Biederman 
Acked-by: Greg Kroah-Hartman 
Signed-off-by: David S. Miller

sysfs: Implement support for tagged files in sysfs.

2011-10-19T23:24:14+00:00

Looking up files in sysfs is hard to understand and analyize because we
currently allow placing untagged files in tagged directories.  In the
implementation of that we have two subtly different meanings of NULL.
NULL meaning there is no tag on a directory entry and NULL meaning
we don't care which namespace the lookup is performed for.  This
multiple uses of NULL have resulted in subtle bugs (since fixed)
in the code.

Currently it is only the bonding driver that needs to have an untagged
file in a tagged directory.

To untagle this mess I am adding support for tagged files to sysfs.
Modifying the bonding driver to implement bonding_masters as a tagged
file.  Registering bonding_masters once for each network namespace.
Then I am removing support for untagged entries in tagged sysfs
directories.

Resulting in code that is much easier to reason about.

Signed-off-by: Eric W. Biederman 
Acked-by: Greg Kroah-Hartman 
Signed-off-by: David S. Miller

sysfs: remove "last sysfs file:" line from the oops messages

2011-05-13T23:05:51+00:00

On some arches (x86, sh, arm, unicore, powerpc) the oops message would
print out the last sysfs file accessed.

This was very useful in finding a number of sysfs and driver core bugs
in the 2.5 and early 2.6 development days, but it has been a number of
years since this file has actually helped in debugging anything that
couldn't also be trivially determined from the stack traceback.

So it's time to delete the line.  This is good as we need all the space
we can get for oops messages at times on consoles.

Acked-by: Phil Carmody 
Acked-by: Ingo Molnar 
Cc: Andrew Morton 
Cc: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

sysfs: checking for NULL instead of ERR_PTR

2010-09-04T00:26:28+00:00

d_path() returns an ERR_PTR and it doesn't return NULL.

Signed-off-by: Dan Carpenter 
Cc: stable 
Reviewed-by: "Eric W. Biederman" 
Signed-off-by: Greg Kroah-Hartman

sysfs: sysfs_chmod_file's attr can be const

2010-08-05T20:53:34+00:00

sysfs_chmod_file doesn't change the attribute it operates on, so this
attribute can be marked const.

Signed-off-by: Jean Delvare 
Signed-off-by: Greg Kroah-Hartman