linux-stable.git/fs/ext2/acl.c, branch linux-3.12.y

posix_acl: Clear SGID bit when setting file permissions

2017-01-27T10:15:59+00:00

commit 073931017b49d9458aa351605b43a7e34598caef upstream.

When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok().  Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2).  Fix that.

Reviewed-by: Christoph Hellwig 
Reviewed-by: Jeff Layton 
Signed-off-by: Jan Kara 
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Jiri Slaby

userns: Convert extN to support kuids and kgids in posix acls

2012-09-18T08:01:36+00:00

Convert ext2, ext3, and ext4 to fully support the posix acl changes,
using e_uid e_gid instead e_id.

Enabled building with posix acls enabled, all filesystems supporting
user namespaces, now also support posix acls when user namespaces are enabled.

Cc: Theodore Tso 
Cc: Andrew Morton 
Cc: Andreas Dilger 
Cc: Jan Kara 
Cc: Al Viro 
Signed-off-by: Eric W. Biederman

userns: Pass a userns parameter into posix_acl_to_xattr and posix_acl_from_xattr

2012-09-18T08:01:35+00:00

 - Pass the user namespace the uid and gid values in the xattr are stored
   in into posix_acl_from_xattr.

 - Pass the user namespace kuid and kgid values should be converted into
   when storing uid and gid values in an xattr in posix_acl_to_xattr.

- Modify all callers of posix_acl_from_xattr and posix_acl_to_xattr to
  pass in &init_user_ns.

In the short term this change is not strictly needed but it makes the
code clearer.  In the longer term this change is necessary to be able to
mount filesystems outside of the initial user namespace that natively
store posix acls in the linux xattr format.

Cc: Theodore Tso 
Cc: Andrew Morton 
Cc: Andreas Dilger 
Cc: Jan Kara 
Cc: Al Viro 
Signed-off-by: "Eric W. Biederman"

switch posix_acl_equiv_mode() to umode_t *

2011-08-01T06:10:06+00:00

... so that &inode->i_mode could be passed to it

Signed-off-by: Al Viro

switch posix_acl_create() to umode_t *

2011-08-01T06:09:42+00:00

so we can pass &inode->i_mode to it

Signed-off-by: Al Viro

fs: take the ACL checks to common code

2011-07-25T18:30:23+00:00

Replace the ->check_acl method with a ->get_acl method that simply reads an
ACL from disk after having a cache miss.  This means we can replace the ACL
checking boilerplate code with a single implementation in namei.c.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

kill boilerplates around posix_acl_create_masq()

2011-07-25T18:27:32+00:00

new helper: posix_acl_create(&acl, gfp, mode_p).  Replaces acl with
modified clone, on failure releases acl and replaces with NULL.
Returns 0 or -ve on error.  All callers of posix_acl_create_masq()
switched.

Signed-off-by: Al Viro

kill boilerplate around posix_acl_chmod_masq()

2011-07-25T18:27:30+00:00

new helper: posix_acl_chmod(&acl, gfp, mode).  Replaces acl with modified
clone or with NULL if that has failed; returns 0 or -ve on error.  All
callers of posix_acl_chmod_masq() switched to that - they'd been doing
exactly the same thing.

Signed-off-by: Al Viro

vfs: move ACL cache lookup into generic code

2011-07-25T18:23:39+00:00

This moves logic for checking the cached ACL values from low-level
filesystems into generic code.  The end result is a streamlined ACL
check that doesn't need to load the inode->i_op->check_acl pointer at
all for the common cached case.

The filesystems also don't need to check for a non-blocking RCU walk
case in their acl_check() functions, because that is all handled at a
VFS layer.

Signed-off-by: Linus Torvalds 
Signed-off-by: Al Viro

->permission() sanitizing: don't pass flags to ->check_acl()

2011-07-20T05:43:21+00:00

not used in the instances anymore.

Signed-off-by: Al Viro