Setting this secFlg allows usage of dfs where some servers require
signing and others don't.
Signed-off-by: NMartijn de Gouw <martijn.de.gouw@prodrive.nl>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Samba rejected libreoffice's attempt to open a file with illegal
O_EXCL (without O_CREAT).  Mask this flag off (as the local
linux file system case does) for this case, so that we
don't have disable Unix Extensions unnecessarily due to
the Samba error (Samba server is also being fixed).

See https://bugzilla.samba.org/show_bug.cgi?id=9519Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Kjell Braden reported this oops:

[  833.211970] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  833.212816] IP: [<          (null)>]           (null)
[  833.213280] PGD 1b9b2067 PUD e9f7067 PMD 0
[  833.213874] Oops: 0010 [#1] SMP
[  833.214344] CPU 0
[  833.214458] Modules linked in: des_generic md4 nls_utf8 cifs vboxvideo drm snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq bnep rfcomm snd_timer bluetooth snd_seq_device ppdev snd vboxguest parport_pc joydev mac_hid soundcore snd_page_alloc psmouse i2c_piix4 serio_raw lp parport usbhid hid e1000
[  833.215629]
[  833.215629] Pid: 1752, comm: mount.cifs Not tainted 3.0.0-rc7-bisectcifs-fec11dd9+ #18 innotek GmbH VirtualBox/VirtualBox
[  833.215629] RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
[  833.215629] RSP: 0018:ffff8800119c9c50  EFLAGS: 00010282
[  833.215629] RAX: ffffffffa02186c0 RBX: ffff88000c427780 RCX: 0000000000000000
[  833.215629] RDX: 0000000000000000 RSI: ffff88000c427780 RDI: ffff88000c4362e8
[  833.215629] RBP: ffff8800119c9c88 R08: ffff88001fc15e30 R09: 00000000d69515c7
[  833.215629] R10: ffffffffa0201972 R11: ffff88000e8f6a28 R12: ffff88000c4362e8
[  833.215629] R13: 0000000000000000 R14: 0000000000000000 R15: ffff88001181aaa6
[  833.215629] FS:  00007f2986171700(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
[  833.215629] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  833.215629] CR2: 0000000000000000 CR3: 000000001b982000 CR4: 00000000000006f0
[  833.215629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  833.215629] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  833.215629] Process mount.cifs (pid: 1752, threadinfo ffff8800119c8000, task ffff88001c1c16f0)
[  833.215629] Stack:
[  833.215629]  ffffffff8116a9b5 ffff8800119c9c88 ffffffff81178075 0000000000000286
[  833.215629]  0000000000000000 ffff88000c4276c0 ffff8800119c9ce8 ffff8800119c9cc8
[  833.215629]  ffffffff8116b06e ffff88001bc6fc00 ffff88000c4276c0 ffff88000c4276c0
[  833.215629] Call Trace:
[  833.215629]  [<ffffffff8116a9b5>] ? d_alloc_and_lookup+0x45/0x90
[  833.215629]  [<ffffffff81178075>] ? d_lookup+0x35/0x60
[  833.215629]  [<ffffffff8116b06e>] __lookup_hash.part.14+0x9e/0xc0
[  833.215629]  [<ffffffff8116b1d6>] lookup_one_len+0x146/0x1e0
[  833.215629]  [<ffffffff815e4f7e>] ? _raw_spin_lock+0xe/0x20
[  833.215629]  [<ffffffffa01eef0d>] cifs_do_mount+0x26d/0x500 [cifs]
[  833.215629]  [<ffffffff81163bd3>] mount_fs+0x43/0x1b0
[  833.215629]  [<ffffffff8117d41a>] vfs_kern_mount+0x6a/0xd0
[  833.215629]  [<ffffffff8117e584>] do_kern_mount+0x54/0x110
[  833.215629]  [<ffffffff8117fdc2>] do_mount+0x262/0x840
[  833.215629]  [<ffffffff81108a0e>] ? __get_free_pages+0xe/0x50
[  833.215629]  [<ffffffff8117f9ca>] ? copy_mount_options+0x3a/0x180
[  833.215629]  [<ffffffff8118075d>] sys_mount+0x8d/0xe0
[  833.215629]  [<ffffffff815ece82>] system_call_fastpath+0x16/0x1b
[  833.215629] Code:  Bad RIP value.
[  833.215629] RIP  [<          (null)>]           (null)
[  833.215629]  RSP <ffff8800119c9c50>
[  833.215629] CR2: 0000000000000000
[  833.238525] ---[ end trace ec00758b8d44f529 ]---

When walking down the path on the server, it's possible to hit a
symlink. The path walking code assumes that the caller will handle that
situation properly, but cifs_get_root() isn't set up for it. This patch
prevents the oops by simply returning an error.

A better solution would be to try and chase the symlinks here, but that's
fairly complicated to handle.

Fixes:

    https://bugzilla.kernel.org/show_bug.cgi?id=53221Reported-and-tested-by: NKjell Braden <afflux@pentabarf.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

* calling conventions change - ERR_PTR() is returned on ->d_hash() errors;
NULL is just for dcache miss now.
* exported, open-coded instances in ncpfs and cifs converted.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Add two helper functions get_option_uid and get_option_gid to handle
the work of parsing uid and gids paramaters from the command line and
making kuids and kgids out of them.

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

In cifs_unix_to_basic_fattr only update the cifs_fattr with an id if
it is valid after conversion.

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Use INVALID_UID and INVALID_GID instead of NO_CHANGE_64 to indicate
the value should not be changed.

In cifs_fill_unix_set_info convert from kuids and kgids into uids and
gids that will fit in FILE_UNIX_BASIC_INFO.

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

Update id_mode_to_cifs_acl to take a kuid_t and a kgid_t.

Replace NO_CHANGE_32 with INVALID_UID and INVALID_GID, and tests for
NO_CHANGE_32 with uid_valid and gid_valid.

Carefully unpack the value returned from request_key.  memcpy the
value into the expected type.  The convert the uid/gid into a
kuid/kgid.  And then only if the result is a valid kuid or kgid update
fuid/fgid.

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

keyring_alloc has been updated to take a kuid_t and kgid_t so
pass GLOBAL_ROOT_UID instead of 0 for the uid and GLOBAL_ROOT_GID
instead of 0 for the gid.

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

The assumption that sizeof(uid_t) is the same as sizeof(gid_t) is
completely reasonable but since we can verify the condition at
compile time.

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

The cifs protocol has a 64bit space for uids and gids, while linux
only supports a 32bit space today.  Instead of silently truncating
64bit cifs ids, replace cifs ids that do not fit in the 32bit linux
id space with the default uid and gids for the cifs mount.

Cc: Steve French <smfrench@gmail.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

When it goes to error through line 144, the memory allocated to *devname is
not freed, and the caller doesn't free it either in line 250. So we free the
memroy of *devname in function cifs_compose_mount_options() when it goes to
error.
Signed-off-by: NCong Ding <dinggnu@gmail.com>
CC: stable <stable@kernel.org>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Steve French <sfrench@samba.org>
CC: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

srcip_matches() previously had code like this:

  srcip_matches(..., struct sockaddr *rhs) {
    /* ... */
    struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *) &rhs;
    return ipv6_addr_equal(..., &vaddr6->sin6_addr);
  }

which interpreted the values on the stack after the 'rhs' pointer as an
ipv6 address.  The correct thing to do is to use 'rhs', not '&rhs'.
Signed-off-by: NNickolai Zeldovich <nickolai@csail.mit.edu>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Correct spelling typo in printk within various drivers.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

If we have mandatory byte-range locks on a file we can't cache reads
because pagereading may have conflicts with these locks on the server.
That's why we should allow level2 oplocks for files without mandatory
locks only.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

If we have a read oplock and set a read lock in it, we can't write to the
locked area - so, filemap_fdatawrite may fail with a no information for a
userspace application even if we request a write to non-locked area. Fix
this by writing directly to the server and then breaking oplock level from
level2 to None.

Also remove CONFIG_CIFS_SMB2 ifdefs because it's suitable for both CIFS
and SMB2 protocols.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

that solution has data races and can end up two identical writes to the
server: when clientCanCacheAll value can be changed during the execution
of __generic_file_aio_write.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

When a call goes out, the signing code adjusts the sequence number
upward by two to account for the request and the response. An NT_CANCEL
however doesn't get a response of its own, it just hurries the server
along to get it to respond to the original request more quickly.
Therefore, we must adjust the sequence number back down by one after
signing a NT_CANCEL request.

Cc: <stable@vger.kernel.org>
Reported-by: NTim Perry <tdparmor-sambabugs@yahoo.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Cai reported this oops:

[90701.616664] BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
[90701.625438] IP: [<ffffffff814a343e>] kernel_setsockopt+0x2e/0x60
[90701.632167] PGD fea319067 PUD 103fda4067 PMD 0
[90701.637255] Oops: 0000 [#1] SMP
[90701.640878] Modules linked in: des_generic md4 nls_utf8 cifs dns_resolver binfmt_misc tun sg igb iTCO_wdt iTCO_vendor_support lpc_ich pcspkr i2c_i801 i2c_core i7core_edac edac_core ioatdma dca mfd_core coretemp kvm_intel kvm crc32c_intel microcode sr_mod cdrom ata_generic sd_mod pata_acpi crc_t10dif ata_piix libata megaraid_sas dm_mirror dm_region_hash dm_log dm_mod
[90701.677655] CPU 10
[90701.679808] Pid: 9627, comm: ls Tainted: G        W    3.7.1+ #10 QCI QSSC-S4R/QSSC-S4R
[90701.688950] RIP: 0010:[<ffffffff814a343e>]  [<ffffffff814a343e>] kernel_setsockopt+0x2e/0x60
[90701.698383] RSP: 0018:ffff88177b431bb8  EFLAGS: 00010206
[90701.704309] RAX: ffff88177b431fd8 RBX: 00007ffffffff000 RCX: ffff88177b431bec
[90701.712271] RDX: 0000000000000003 RSI: 0000000000000006 RDI: 0000000000000000
[90701.720223] RBP: ffff88177b431bc8 R08: 0000000000000004 R09: 0000000000000000
[90701.728185] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
[90701.736147] R13: ffff88184ef92000 R14: 0000000000000023 R15: ffff88177b431c88
[90701.744109] FS:  00007fd56a1a47c0(0000) GS:ffff88105fc40000(0000) knlGS:0000000000000000
[90701.753137] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[90701.759550] CR2: 0000000000000028 CR3: 000000104f15f000 CR4: 00000000000007e0
[90701.767512] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[90701.775465] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[90701.783428] Process ls (pid: 9627, threadinfo ffff88177b430000, task ffff88185ca4cb60)
[90701.792261] Stack:
[90701.794505]  0000000000000023 ffff88177b431c50 ffff88177b431c38 ffffffffa014fcb1
[90701.802809]  ffff88184ef921bc 0000000000000000 00000001ffffffff ffff88184ef921c0
[90701.811123]  ffff88177b431c08 ffffffff815ca3d9 ffff88177b431c18 ffff880857758000
[90701.819433] Call Trace:
[90701.822183]  [<ffffffffa014fcb1>] smb_send_rqst+0x71/0x1f0 [cifs]
[90701.828991]  [<ffffffff815ca3d9>] ? schedule+0x29/0x70
[90701.834736]  [<ffffffffa014fe6d>] smb_sendv+0x3d/0x40 [cifs]
[90701.841062]  [<ffffffffa014fe96>] smb_send+0x26/0x30 [cifs]
[90701.847291]  [<ffffffffa015801f>] send_nt_cancel+0x6f/0xd0 [cifs]
[90701.854102]  [<ffffffffa015075e>] SendReceive+0x18e/0x360 [cifs]
[90701.860814]  [<ffffffffa0134a78>] CIFSFindFirst+0x1a8/0x3f0 [cifs]
[90701.867724]  [<ffffffffa013f731>] ? build_path_from_dentry+0xf1/0x260 [cifs]
[90701.875601]  [<ffffffffa013f731>] ? build_path_from_dentry+0xf1/0x260 [cifs]
[90701.883477]  [<ffffffffa01578e6>] cifs_query_dir_first+0x26/0x30 [cifs]
[90701.890869]  [<ffffffffa015480d>] initiate_cifs_search+0xed/0x250 [cifs]
[90701.898354]  [<ffffffff81195970>] ? fillonedir+0x100/0x100
[90701.904486]  [<ffffffffa01554cb>] cifs_readdir+0x45b/0x8f0 [cifs]
[90701.911288]  [<ffffffff81195970>] ? fillonedir+0x100/0x100
[90701.917410]  [<ffffffff81195970>] ? fillonedir+0x100/0x100
[90701.923533]  [<ffffffff81195970>] ? fillonedir+0x100/0x100
[90701.929657]  [<ffffffff81195848>] vfs_readdir+0xb8/0xe0
[90701.935490]  [<ffffffff81195b9f>] sys_getdents+0x8f/0x110
[90701.941521]  [<ffffffff815d3b99>] system_call_fastpath+0x16/0x1b
[90701.948222] Code: 66 90 55 65 48 8b 04 25 f0 c6 00 00 48 89 e5 53 48 83 ec 08 83 fe 01 48 8b 98 48 e0 ff ff 48 c7 80 48 e0 ff ff ff ff ff ff 74 22 <48> 8b 47 28 ff 50 68 65 48 8b 14 25 f0 c6 00 00 48 89 9a 48 e0
[90701.970313] RIP  [<ffffffff814a343e>] kernel_setsockopt+0x2e/0x60
[90701.977125]  RSP <ffff88177b431bb8>
[90701.981018] CR2: 0000000000000028
[90701.984809] ---[ end trace 24bd602971110a43 ]---

This is likely due to a race vs. a reconnection event.

The current code checks for a NULL socket in smb_send_kvec, but that's
too late. By the time that check is done, the socket will already have
been passed to kernel_setsockopt. Move the check into smb_send_rqst, so
that it's checked earlier.

In truth, this is a bit of a half-assed fix. The -ENOTSOCK error
return here looks like it could bubble back up to userspace. The locking
rules around the ssocket pointer are really unclear as well. There are
cases where the ssocket pointer is changed without holding the srv_mutex,
but I'm not clear whether there's a potential race here yet or not.

This code seems like it could benefit from some fundamental re-think of
how the socket handling should behave. Until then though, this patch
should at least fix the above oops in most cases.

Cc: <stable@vger.kernel.org> # 3.7+
Reported-and-Tested-by: NCAI Qian <caiqian@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

It's always set to "1" and there's no way to change it to anything else.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Oliver reported that commit cd60042c caused his cifs mounts to
continually thrash through new inodes on readdir. His servers are not
sending inode numbers (or he's not using them), and the new test in
that function doesn't account for that sort of setup correctly.

If we're not using server inode numbers, then assume that the inode
attached to the dentry hasn't changed. Go ahead and update the
attributes in place, but keep the same inode number.

Cc: <stable@vger.kernel.org> # v3.5+
Reported-and-Tested-by: NOliver Mössinger <Oliver.Moessinger@ichaus.de>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Dan reported the following regression in commit d387a5c5:

    + fs/cifs/connect.c:1903 cifs_parse_mount_options() error: double free of 'string'

That patch has some of the new option parsing code free "string" without
setting the variable to NULL afterward. Since "string" is automatically
freed in an error condition, fix the code to just rely on that instead
of freeing it explicitly.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

But the kernel decided to call it "origin" instead.  Fix most of the
sites.
Acked-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If we have a read oplock and set a read lock in it, we can't write to the
locked area - so, filemap_fdatawrite may fail with a no information for a
userspace application even if we request a write to non-locked area. Fix
this by populating the page cache without marking affected pages dirty
after a successful write directly to the server.

Also remove CONFIG_CIFS_SMB2 ifdefs because it's suitable for both CIFS
and SMB2 protocols.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

This should fix a regression that was introduced when the new mount
option parser went in. Also, when the unc= and prefixpath= options
are provided, check their values against the ones we parsed from
the device string. If they differ, then throw a warning that tells
the user that we're using the values from the unc= option for now,
but that that will change in 3.10.

Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Currently the code takes care to ensure that the prefixpath has a
leading '/' delimiter. What if someone passes us a prefixpath with a
leading '\\' instead? The code doesn't properly handle that currently
AFAICS.

Let's just change the code to skip over any leading delimiter character
when copying the prepath. Then, fix up the users of the prepath option
to prefix it with the correct delimiter when they use it.

Also, there's no need to limit the length of the prefixpath to 1k. If
the server can handle it, why bother forbidding it?

Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Make sure we free any existing memory allocated for vol->UNC, just in
case someone passes in multiple unc= options.

Get rid of the check for too long a UNC. The check for >300 bytes seems
arbitrary. We later copy this into the tcon->treeName, for instance and
it's a lot shorter than 300 bytes.

Eliminate an extra kmalloc and copy as well. Just set the vol->UNC
directly with the contents of match_strdup.

Establish that the UNC should be stored with '\\' delimiters. Use
convert_delimiter to change it in place in the vol->UNC.

Finally, move the check for a malformed UNC into
cifs_parse_mount_options so we can catch that situation earlier.

Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

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: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

SMB2 and later will return only 1 credit for session setup (phase 1)
not just for the negotiate protocol response.  Do not disable
echoes and oplocks on session setup (we only need one credit
for tree connection anyway) as a resonse with only 1 credit
on phase 1 of sessionsetup is expected.

Fixes the "CIFS VFS: disabling echoes and oplocks" message
logged to dmesg.
Signed-off-by: NSteve French <smfrench@gmail.com>
Acked-by: NJeff Layton <jlayton@samba.org>

Restructure code to make SMB2 vs. SMB3 signing a protocol
specific op.  SMB3 signing (AES_CMAC) is not enabled yet,
but this restructuring at least makes sure we don't send
an smb2 signature on an smb3 signed connection. A followon
patch will add AES_CMAC and enable smb3 signing.
Signed-off-by: NSteve French <smfrench@gmail.com>
Acked-by: NJeff Layton <jlayton@samba.org>

A SID could potentially be embedded inside of payload.value if there are
no subauthorities, and the arch has 8 byte pointers. Allow for that
possibility there.

While we're at it, rephrase the "embedding" check in terms of
key->payload to allow for the possibility that the union might change
size in the future.
Reviewed-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

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: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Now that we aren't so rigid about the length of the key being passed
in, we need to be a bit more rigorous about checking the length of
the actual data against the claimed length (a'la num_subauths field).

Check for the case where userspace sends us a seemingly valid key
with a num_subauths field that goes beyond the end of the array. If
that happens, return -EIO and invalidate the key.

Also change the other places where we check for malformed keys in this
code to invalidate the key as well.
Reviewed-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>