Commit Graph

29 Commits

Author SHA1 Message Date
Aurelien Aptel 0892ba693f cifs: modefromsid: make room for 4 ACE
when mounting with modefromsid, we end up writing 4 ACE in a security
descriptor that only has room for 3, thus triggering an out-of-bounds
write. fix this by changing the min size of a security descriptor.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-16 11:43:38 -05:00
Shirish Pargaonkar ee25c6dd7b cifs: For SMB2 security informaion query, check for minimum sized security descriptor instead of sizeof FileAllInformation class
Validate_buf () function checks for an expected minimum sized response
passed to query_info() function.
For security information, the size of a security descriptor can be
smaller (one subauthority, no ACEs) than the size of the structure
that defines FileInfoClass of FileAllInformation.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199725
Cc: <stable@vger.kernel.org>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Noah Morrison <noah.morrison@rubrik.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-04 19:19:24 -05:00
Jeff Layton 193cdd8a29 cifs: fix SID binary to string conversion
The authority fields are supposed to be represented by a single 48-bit
value. It's also supposed to represent the value as hex if it's equal to
or greater than 2^32. This is documented in MS-DTYP, section 2.4.2.1.

Also, fix up the max string length to account for this fix.

Acked-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-11 11:48:49 -06:00
Jeff Layton 7ee0b4c635 cifs: fix hardcoded default security descriptor length
It was hardcoded to 192 bytes, which was not enough when the max number
of subauthorities went to 15. Redefine this constant in terms of sizeof
the structs involved, and rename it for better clarity.

While we're at it, remove a couple more unused constants from cifsacl.h.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-08 22:04:35 -06:00
Jeff Layton faa65f07d2 cifs: simplify id_to_sid and sid_to_id mapping code
The cifs.idmap handling code currently causes the kernel to cache the
data from userspace twice. It first looks in a rbtree to see if there is
a matching entry for the given id. If there isn't then it calls
request_key which then checks its cache and then calls out to userland
if it doesn't have one. If the userland program establishes a mapping
and downcalls with that info, it then gets cached in the keyring and in
this rbtree.

Aside from the double memory usage and the performance penalty in doing
all of these extra copies, there are some nasty bugs in here too. The
code declares four rbtrees and spinlocks to protect them, but only seems
to use two of them. The upshot is that the same tree is used to hold
(eg) uid:sid and sid:uid mappings. The comparitors aren't equipped to
deal with that.

I think we'd be best off to remove a layer of caching in this code. If
this was originally done for performance reasons, then that really seems
like a premature optimization.

This patch does that -- it removes the rbtrees and the locks that
protect them and simply has the code do a request_key call on each call
into sid_to_id and id_to_sid. This greatly simplifies this code and
should roughly halve the memory utilization from using the idmapping
code.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-08 22:04:25 -06:00
Jeff Layton b1a6dc21d1 cifs: remove uneeded __KERNEL__ block from cifsacl.h
...and make those symbols static in cifsacl.c. Nothing outside
of that file refers to them.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-05 13:13:11 -06:00
Jeff Layton 30c9d6cca5 cifs: redefine NUM_SUBAUTH constant from 5 to 15
According to several places on the Internet and the samba winbind code,
this is hard limited to 15 in windows, not 5. This does balloon out
the allocation of each by 40 bytes, but I don't see any alternative.

Also, rename it to SID_MAX_SUB_AUTHORITIES to match the alleged name
of this constant in the windows header files

Finally, rename SIDLEN to SID_STRING_MAX, fix the value to reflect
the change to SID_MAX_SUB_AUTHORITIES and document how it was
determined.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-05 13:13:11 -06:00
Jeff Layton 36f87ee70f cifs: make cifs_copy_sid handle a source sid with variable size subauth arrays
...and lift the restriction in id_to_sid upcall that the size must be
at least as big as a full cifs_sid.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-05 13:13:11 -06:00
Jeff Layton 436bb435fc cifs: make compare_sids static
..nothing outside of cifsacl.c calls it. Also fix the incorrect
comment on the function. It returns 0 when they match.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-05 13:13:11 -06:00
Jeff Layton 852e22950d cifs: use the NUM_AUTHS and NUM_SUBAUTHS constants in cifsacl code
...instead of hardcoding in '5' and '6' all over the place.

Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2012-12-05 13:13:10 -06:00
Shirish Pargaonkar c4aca0c09f cifs: Change key name to cifs.idmap, misc. clean-up
Change idmap key name from cifs.cifs_idmap to cifs.idmap.
Removed unused structure wksidarr and function match_sid().
Handle errors correctly in function init_cifs().

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-05-19 14:10:56 +00:00
Shirish Pargaonkar 9409ae58e0 cifs: Invoke id mapping functions (try #17 repost)
rb tree search and insertion routines.

A SID which needs to be mapped, is looked up in one of the rb trees
depending on whether SID is either owner or group SID.
If found in the tree, a (mapped) id from that node is assigned to
uid or gid as appropriate.  If unmapped, an upcall is attempted to
map the SID to an id.  If upcall is successful, node is marked as
mapped.  If upcall fails, node stays marked as unmapped and a mapping
is attempted again only after an arbitrary time period has passed.

To map a SID, which can be either a Owner SID or a Group SID, key
description starts with the string "os" or "gs" followed by SID converted
to a string. Without "os" or "gs", cifs.upcall does not know whether
SID needs to be mapped to either an uid or a gid.

Nodes in rb tree have fields to prevent multiple upcalls for
a SID.  Searching, adding, and removing nodes is done within global locks.
Whenever a node is either found or inserted in a tree, a reference
is taken on that node.
Shrinker routine prunes a node if it has expired but does not prune
an expired node if its refcount is not zero (i.e. sid/id of that node
is_being/will_be accessed).
Thus a node, if its SID needs to be mapped by making an upcall,
can safely stay and its fields accessed without shrinker pruning it.
A reference (refcount) is put on the node without holding the spinlock
but a reference is get on the node by holding the spinlock.

Every time an existing mapped node is accessed or mapping is attempted,
its timestamp is updated to prevent it from getting erased or a
to prevent multiple unnecessary repeat mapping retries respectively.

For now, cifs.upcall is only used to map a SID to an id (uid or gid) but
it would be used to obtain an SID for an id.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-05-19 14:10:51 +00:00
Jeff Layton 79df1baeec cifs: fix use of CONFIG_CIFS_ACL
Some of the code under CONFIG_CIFS_ACL is dependent upon code under
CONFIG_CIFS_EXPERIMENTAL, but the Kconfig options don't reflect that
dependency. Move more of the ACL code out from under
CONFIG_CIFS_EXPERIMENTAL and under CONFIG_CIFS_ACL.

Also move find_readable_file out from other any sort of Kconfig
option and make it a function normally compiled in.

Reported-and-Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-06 20:22:39 +00:00
Steve French cce246ee5f [CIFS] Fix acl length when very short ACL being modified by chmod
Signed-off-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-04-09 20:55:31 +00:00
Steve French 63d2583f5a [CIFS] Fix walking out end of cifs dacl
Acked-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-11-05 21:46:10 +00:00
Steve French d61e5808d9 [CIFS] acl support part 7
Also fixes typo, build break

Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-10-26 04:32:43 +00:00
Steve French 44093ca2fe [CIFS] acl support part 6
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-10-23 21:22:55 +00:00
Steve French a750e77c21 [CIFS] acl support part 4
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-10-17 22:50:39 +00:00
Steve French af6f4612fd [CIFS] Fix some endianness problems in new acl code
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-10-16 18:40:37 +00:00
Cyril Gorcunov 8f2376adfb [CIFS] Fix endian conversion problem in posix mkdir
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-10-14 17:58:43 +00:00
Steve French 297647c21f [CIFS] CIFS ACL support part 3
Signed-off-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-10-12 04:11:59 +00:00
Shirish Pargaonkar d0d66c443a [CIFS] CIFS ACL support (part 2)
Signed-off-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-10-03 18:22:19 +00:00
Steve French 4084973dba [CIFS] change misleading field name
num_auth is really num_subauth in ACL terminology

Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-10-01 19:59:01 +00:00
Steve French bcb020341a [CIFS] move cifs acl code to new file and fix build break
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-09-25 16:17:24 +00:00
Steve French 442aa310f3 [CIFS] Support for CIFS ACLs (part 1)
Add code to be able to dump CIFS ACL information
when Query Posix ACL with cifsacl mount parm enabled.

Signed-off-by: Shirish Pargoankar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2007-09-24 20:25:46 +00:00
Steve French 2cd646a2d1 [CIFS] Remove static and unused symbols
Most cases of the ones found by Shaggy by
	"make namespacecheck"
could be removed or made static

Ack: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2006-09-28 19:43:08 +00:00
Steve French eeac8047fc [CIFS] Fix CIFS to recognize share mode security
Fix Samba bugzilla bug 3301

In share mode encrypted password must be sent on tree connection (in our
case only the NTLM password is sent, not the older LANMAN one).

Signed-off-by: Steve French <sfrench@us.ibm.com>
2006-01-13 21:34:58 -08:00
Steve French a6230af7bd [CIFS] Minor cleanup to new cifs acl header.
Signed-off-by: Steve French <sfrench@us.ibm.com>
2006-01-08 20:04:55 -08:00
Steve French bf82067917 [CIFS] Kerberos and CIFS ACL support part 1
Signed-off-by: Steve French <sfrench@us.ibm.com>
2005-12-01 22:32:42 -08:00