diff mbox

cifs: Fix stack out-of-bounds in smb{2,3}_create_lease_buf()

Message ID 7d1bdccbf42a239ac1096393bfa1f7a248e1feba.1530783326.git.sbrivio@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Stefano Brivio July 5, 2018, 9:45 a.m. UTC 
smb{2,3}_create_lease_buf() store a lease key in the lease
context for later usage on a lease break. The key is currently
sourced from data that happens to be on the stack near oplock,
a local variable in open_shroot(). Its address is then passed
to create_lease_buf handlers via SMB2_open(), and 16 bytes near
oplock are used. This causes a stack out-of-bounds access as
reported by KASAN on SMB2.1 and SMB3 mounts (first out-of-bounds
access is shown here):

[  111.528823] BUG: KASAN: stack-out-of-bounds in smb3_create_lease_buf+0x399/0x3b0 [cifs]
[  111.530815] Read of size 8 at addr ffff88010829f249 by task mount.cifs/985
[  111.532838] CPU: 3 PID: 985 Comm: mount.cifs Not tainted 4.18.0-rc3+ #91
[  111.534656] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[  111.536838] Call Trace:
[  111.537528]  dump_stack+0xc2/0x16b
[  111.540890]  print_address_description+0x6a/0x270
[  111.542185]  kasan_report+0x258/0x380
[  111.544701]  smb3_create_lease_buf+0x399/0x3b0 [cifs]
[  111.546134]  SMB2_open+0x1ef8/0x4b70 [cifs]
[  111.575883]  open_shroot+0x339/0x550 [cifs]
[  111.591969]  smb3_qfs_tcon+0x32c/0x1e60 [cifs]
[  111.617405]  cifs_mount+0x4f3/0x2fc0 [cifs]
[  111.674332]  cifs_smb3_do_mount+0x263/0xf10 [cifs]
[  111.677915]  mount_fs+0x55/0x2b0
[  111.679504]  vfs_kern_mount.part.22+0xaa/0x430
[  111.684511]  do_mount+0xc40/0x2660
[  111.698301]  ksys_mount+0x80/0xd0
[  111.701541]  do_syscall_64+0x14e/0x4b0
[  111.711807]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  111.713665] RIP: 0033:0x7f372385b5fa
[  111.715311] Code: 48 8b 0d 99 78 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 66 78 2c 00 f7 d8 64 89 01 48
[  111.720330] RSP: 002b:00007ffff27049d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
[  111.722601] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f372385b5fa
[  111.724842] RDX: 000055c2ecdc73b2 RSI: 000055c2ecdc73f9 RDI: 00007ffff270580f
[  111.727083] RBP: 00007ffff2705804 R08: 000055c2ee976060 R09: 0000000000001000
[  111.729319] R10: 0000000000000000 R11: 0000000000000206 R12: 00007f3723f4d000
[  111.731615] R13: 000055c2ee976060 R14: 00007f3723f4f90f R15: 0000000000000000

[  111.735448] The buggy address belongs to the page:
[  111.737420] page:ffffea000420a7c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
[  111.739890] flags: 0x17ffffc0000000()
[  111.741750] raw: 0017ffffc0000000 0000000000000000 dead000000000200 0000000000000000
[  111.744216] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
[  111.746679] page dumped because: kasan: bad access detected

[  111.750482] Memory state around the buggy address:
[  111.752562]  ffff88010829f100: 00 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 00
[  111.754991]  ffff88010829f180: 00 00 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
[  111.757401] >ffff88010829f200: 00 00 00 00 00 f1 f1 f1 f1 01 f2 f2 f2 f2 f2 f2
[  111.759801]                                               ^
[  111.762034]  ffff88010829f280: f2 02 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00
[  111.764486]  ffff88010829f300: f2 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  111.766913] ==================================================================

Generate lease keys by properly gathering random data instead.

Fixes: b8c32dbb0deb ("CIFS: Request SMB2.1 leases")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
 fs/cifs/cifsglob.h |  2 +-
 fs/cifs/smb2ops.c  | 13 +++++--------
 fs/cifs/smb2pdu.c  |  2 +-
 fs/cifs/smb2pdu.h  |  6 ++----
 4 files changed, 9 insertions(+), 14 deletions(-)

Comments

Aurélien Aptel July 5, 2018, 11:30 a.m. UTC | #1 
Hi Stefano,

Good catch! But I think this bug hides a bigger more sinister bug...

Stefano Brivio <sbrivio@redhat.com> writes:
> -	buf->lcontext.LeaseKeyLow = cpu_to_le64(*((u64 *)lease_key));
> -	buf->lcontext.LeaseKeyHigh = cpu_to_le64(*((u64 *)(lease_key + 8)));
> +	get_random_bytes(&buf->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
>  	buf->lcontext.LeaseState = map_oplock_to_lease(oplock);

I know the value used to be kind of random and changing it to actual
random bytes should be the same however we already have a function to
generate a lease key in the generic version operations:

	/* generate new lease key */
	void (*new_lease_key)(struct cifs_fid *);

Which are used to set the lease key in a struct cifs_fid and are called
on both create & open code paths (in cifs_create and cifs_atomic_open).

I think the code is assuming being called by smb2_open_file():

	__u8 smb2_oplock[17]; <--- space for oplock type + key buffer
	...
	*smb2_oplock = SMB2_OPLOCK_LEVEL_BATCH;
	...
	if (oparms->tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING)
		memcpy(smb2_oplock + 1, fid->lease_key, SMB2_LEASE_KEY_SIZE);
	...		
	rc = SMB2_open(xid, oparms, smb2_path, smb2_oplock, smb2_data, NULL,
		       NULL);

So it seems all SMB2_open() callers that request an oplock MUST allocate this 17 bytes
buffer and from a quick look many of them don't. The proper fix would be
to pass the fid->lease_key when creating the context.

Hope that was helpful enough for a v2 ;)

Cheers,
Stefano Brivio July 5, 2018, 12:42 p.m. UTC | #2 
Hi Aurélien,

On Thu, 05 Jul 2018 13:30:43 +0200
Aurélien Aptel <aaptel@suse.com> wrote:

> Hi Stefano,
> 
> Good catch! But I think this bug hides a bigger more sinister bug...
> 
> Stefano Brivio <sbrivio@redhat.com> writes:
> > -	buf->lcontext.LeaseKeyLow = cpu_to_le64(*((u64 *)lease_key));
> > -	buf->lcontext.LeaseKeyHigh = cpu_to_le64(*((u64 *)(lease_key + 8)));
> > +	get_random_bytes(&buf->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
> >  	buf->lcontext.LeaseState = map_oplock_to_lease(oplock);  
> 
> I know the value used to be kind of random and changing it to actual
> random bytes should be the same however we already have a function to
> generate a lease key in the generic version operations:
> 
> 	/* generate new lease key */
> 	void (*new_lease_key)(struct cifs_fid *);
> 
> Which are used to set the lease key in a struct cifs_fid and are called
> on both create & open code paths (in cifs_create and cifs_atomic_open).
> 
> I think the code is assuming being called by smb2_open_file():
> 
> 	__u8 smb2_oplock[17]; <--- space for oplock type + key buffer
> 	...
> 	*smb2_oplock = SMB2_OPLOCK_LEVEL_BATCH;
> 	...
> 	if (oparms->tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING)
> 		memcpy(smb2_oplock + 1, fid->lease_key, SMB2_LEASE_KEY_SIZE);
> 	...		
> 	rc = SMB2_open(xid, oparms, smb2_path, smb2_oplock, smb2_data, NULL,
> 		       NULL);
> 
> So it seems all SMB2_open() callers that request an oplock MUST allocate this 17 bytes
> buffer and from a quick look many of them don't.

Aha! I didn't spot that. Everything makes sense now. Thanks for the
explanation!

> The proper fix would be to pass the fid->lease_key when creating the context.
> 
> Hope that was helpful enough for a v2 ;)

Indeed, that was extremely helpful. Preparing v2 now.
Steve French July 5, 2018, 3:17 p.m. UTC | #3 
if this is as expected we will need to cc:stable as well
On Thu, Jul 5, 2018 at 4:46 AM Stefano Brivio <sbrivio@redhat.com> wrote:
>
> smb{2,3}_create_lease_buf() store a lease key in the lease
> context for later usage on a lease break. The key is currently
> sourced from data that happens to be on the stack near oplock,
> a local variable in open_shroot(). Its address is then passed
> to create_lease_buf handlers via SMB2_open(), and 16 bytes near
> oplock are used. This causes a stack out-of-bounds access as
> reported by KASAN on SMB2.1 and SMB3 mounts (first out-of-bounds
> access is shown here):
>
> [  111.528823] BUG: KASAN: stack-out-of-bounds in smb3_create_lease_buf+0x399/0x3b0 [cifs]
> [  111.530815] Read of size 8 at addr ffff88010829f249 by task mount.cifs/985
> [  111.532838] CPU: 3 PID: 985 Comm: mount.cifs Not tainted 4.18.0-rc3+ #91
> [  111.534656] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
> [  111.536838] Call Trace:
> [  111.537528]  dump_stack+0xc2/0x16b
> [  111.540890]  print_address_description+0x6a/0x270
> [  111.542185]  kasan_report+0x258/0x380
> [  111.544701]  smb3_create_lease_buf+0x399/0x3b0 [cifs]
> [  111.546134]  SMB2_open+0x1ef8/0x4b70 [cifs]
> [  111.575883]  open_shroot+0x339/0x550 [cifs]
> [  111.591969]  smb3_qfs_tcon+0x32c/0x1e60 [cifs]
> [  111.617405]  cifs_mount+0x4f3/0x2fc0 [cifs]
> [  111.674332]  cifs_smb3_do_mount+0x263/0xf10 [cifs]
> [  111.677915]  mount_fs+0x55/0x2b0
> [  111.679504]  vfs_kern_mount.part.22+0xaa/0x430
> [  111.684511]  do_mount+0xc40/0x2660
> [  111.698301]  ksys_mount+0x80/0xd0
> [  111.701541]  do_syscall_64+0x14e/0x4b0
> [  111.711807]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [  111.713665] RIP: 0033:0x7f372385b5fa
> [  111.715311] Code: 48 8b 0d 99 78 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 66 78 2c 00 f7 d8 64 89 01 48
> [  111.720330] RSP: 002b:00007ffff27049d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
> [  111.722601] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f372385b5fa
> [  111.724842] RDX: 000055c2ecdc73b2 RSI: 000055c2ecdc73f9 RDI: 00007ffff270580f
> [  111.727083] RBP: 00007ffff2705804 R08: 000055c2ee976060 R09: 0000000000001000
> [  111.729319] R10: 0000000000000000 R11: 0000000000000206 R12: 00007f3723f4d000
> [  111.731615] R13: 000055c2ee976060 R14: 00007f3723f4f90f R15: 0000000000000000
>
> [  111.735448] The buggy address belongs to the page:
> [  111.737420] page:ffffea000420a7c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
> [  111.739890] flags: 0x17ffffc0000000()
> [  111.741750] raw: 0017ffffc0000000 0000000000000000 dead000000000200 0000000000000000
> [  111.744216] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
> [  111.746679] page dumped because: kasan: bad access detected
>
> [  111.750482] Memory state around the buggy address:
> [  111.752562]  ffff88010829f100: 00 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 00
> [  111.754991]  ffff88010829f180: 00 00 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
> [  111.757401] >ffff88010829f200: 00 00 00 00 00 f1 f1 f1 f1 01 f2 f2 f2 f2 f2 f2
> [  111.759801]                                               ^
> [  111.762034]  ffff88010829f280: f2 02 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00
> [  111.764486]  ffff88010829f300: f2 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> [  111.766913] ==================================================================
>
> Generate lease keys by properly gathering random data instead.
>
> Fixes: b8c32dbb0deb ("CIFS: Request SMB2.1 leases")
> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
> ---
>  fs/cifs/cifsglob.h |  2 +-
>  fs/cifs/smb2ops.c  | 13 +++++--------
>  fs/cifs/smb2pdu.c  |  2 +-
>  fs/cifs/smb2pdu.h  |  6 ++----
>  4 files changed, 9 insertions(+), 14 deletions(-)
>
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index bd78da59a4fd..8bb4748249dc 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -423,7 +423,7 @@ struct smb_version_operations {
>         void (*set_oplock_level)(struct cifsInodeInfo *, __u32, unsigned int,
>                                  bool *);
>         /* create lease context buffer for CREATE request */
> -       char * (*create_lease_buf)(u8 *, u8);
> +       char * (*create_lease_buf)(u8);
>         /* parse lease context buffer and return oplock/epoch info */
>         __u8 (*parse_lease_buf)(void *buf, unsigned int *epoch, char *lkey);
>         ssize_t (*copychunk_range)(const unsigned int,
> diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> index 0356b5559c71..d549704c54d5 100644
> --- a/fs/cifs/smb2ops.c
> +++ b/fs/cifs/smb2ops.c
> @@ -2211,7 +2211,7 @@ map_oplock_to_lease(u8 oplock)
>  }
>
>  static char *
> -smb2_create_lease_buf(u8 *lease_key, u8 oplock)
> +smb2_create_lease_buf(u8 oplock)
>  {
>         struct create_lease *buf;
>
> @@ -2219,8 +2219,7 @@ smb2_create_lease_buf(u8 *lease_key, u8 oplock)
>         if (!buf)
>                 return NULL;
>
> -       buf->lcontext.LeaseKeyLow = cpu_to_le64(*((u64 *)lease_key));
> -       buf->lcontext.LeaseKeyHigh = cpu_to_le64(*((u64 *)(lease_key + 8)));
> +       get_random_bytes(&buf->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
>         buf->lcontext.LeaseState = map_oplock_to_lease(oplock);
>
>         buf->ccontext.DataOffset = cpu_to_le16(offsetof
> @@ -2238,7 +2237,7 @@ smb2_create_lease_buf(u8 *lease_key, u8 oplock)
>  }
>
>  static char *
> -smb3_create_lease_buf(u8 *lease_key, u8 oplock)
> +smb3_create_lease_buf(u8 oplock)
>  {
>         struct create_lease_v2 *buf;
>
> @@ -2246,8 +2245,7 @@ smb3_create_lease_buf(u8 *lease_key, u8 oplock)
>         if (!buf)
>                 return NULL;
>
> -       buf->lcontext.LeaseKeyLow = cpu_to_le64(*((u64 *)lease_key));
> -       buf->lcontext.LeaseKeyHigh = cpu_to_le64(*((u64 *)(lease_key + 8)));
> +       get_random_bytes(&buf->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
>         buf->lcontext.LeaseState = map_oplock_to_lease(oplock);
>
>         buf->ccontext.DataOffset = cpu_to_le16(offsetof
> @@ -2284,8 +2282,7 @@ smb3_parse_lease_buf(void *buf, unsigned int *epoch, char *lease_key)
>         if (lc->lcontext.LeaseFlags & SMB2_LEASE_FLAG_BREAK_IN_PROGRESS)
>                 return SMB2_OPLOCK_LEVEL_NOCHANGE;
>         if (lease_key)
> -               memcpy(lease_key, &lc->lcontext.LeaseKeyLow,
> -                      SMB2_LEASE_KEY_SIZE);
> +               memcpy(lease_key, &lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
>         return le32_to_cpu(lc->lcontext.LeaseState);
>  }
>
> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> index 810b85787c91..7608c241b1ef 100644
> --- a/fs/cifs/smb2pdu.c
> +++ b/fs/cifs/smb2pdu.c
> @@ -1712,7 +1712,7 @@ add_lease_context(struct TCP_Server_Info *server, struct kvec *iov,
>         struct smb2_create_req *req = iov[0].iov_base;
>         unsigned int num = *num_iovec;
>
> -       iov[num].iov_base = server->ops->create_lease_buf(oplock+1, *oplock);
> +       iov[num].iov_base = server->ops->create_lease_buf(*oplock);
>         if (iov[num].iov_base == NULL)
>                 return -ENOMEM;
>         iov[num].iov_len = server->vals->create_lease_size;
> diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
> index 824dddeee3f2..a671adcc44a6 100644
> --- a/fs/cifs/smb2pdu.h
> +++ b/fs/cifs/smb2pdu.h
> @@ -678,16 +678,14 @@ struct create_context {
>  #define SMB2_LEASE_KEY_SIZE 16
>
>  struct lease_context {
> -       __le64 LeaseKeyLow;
> -       __le64 LeaseKeyHigh;
> +       u8 LeaseKey[SMB2_LEASE_KEY_SIZE];
>         __le32 LeaseState;
>         __le32 LeaseFlags;
>         __le64 LeaseDuration;
>  } __packed;
>
>  struct lease_context_v2 {
> -       __le64 LeaseKeyLow;
> -       __le64 LeaseKeyHigh;
> +       u8 LeaseKey[SMB2_LEASE_KEY_SIZE];
>         __le32 LeaseState;
>         __le32 LeaseFlags;
>         __le64 LeaseDuration;
> --
> 2.15.1
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index bd78da59a4fd..8bb4748249dc 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -423,7 +423,7 @@  struct smb_version_operations {
 	void (*set_oplock_level)(struct cifsInodeInfo *, __u32, unsigned int,
 				 bool *);
 	/* create lease context buffer for CREATE request */
-	char * (*create_lease_buf)(u8 *, u8);
+	char * (*create_lease_buf)(u8);
 	/* parse lease context buffer and return oplock/epoch info */
 	__u8 (*parse_lease_buf)(void *buf, unsigned int *epoch, char *lkey);
 	ssize_t (*copychunk_range)(const unsigned int,
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 0356b5559c71..d549704c54d5 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -2211,7 +2211,7 @@  map_oplock_to_lease(u8 oplock)
 }
 
 static char *
-smb2_create_lease_buf(u8 *lease_key, u8 oplock)
+smb2_create_lease_buf(u8 oplock)
 {
 	struct create_lease *buf;
 
@@ -2219,8 +2219,7 @@  smb2_create_lease_buf(u8 *lease_key, u8 oplock)
 	if (!buf)
 		return NULL;
 
-	buf->lcontext.LeaseKeyLow = cpu_to_le64(*((u64 *)lease_key));
-	buf->lcontext.LeaseKeyHigh = cpu_to_le64(*((u64 *)(lease_key + 8)));
+	get_random_bytes(&buf->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
 	buf->lcontext.LeaseState = map_oplock_to_lease(oplock);
 
 	buf->ccontext.DataOffset = cpu_to_le16(offsetof
@@ -2238,7 +2237,7 @@  smb2_create_lease_buf(u8 *lease_key, u8 oplock)
 }
 
 static char *
-smb3_create_lease_buf(u8 *lease_key, u8 oplock)
+smb3_create_lease_buf(u8 oplock)
 {
 	struct create_lease_v2 *buf;
 
@@ -2246,8 +2245,7 @@  smb3_create_lease_buf(u8 *lease_key, u8 oplock)
 	if (!buf)
 		return NULL;
 
-	buf->lcontext.LeaseKeyLow = cpu_to_le64(*((u64 *)lease_key));
-	buf->lcontext.LeaseKeyHigh = cpu_to_le64(*((u64 *)(lease_key + 8)));
+	get_random_bytes(&buf->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
 	buf->lcontext.LeaseState = map_oplock_to_lease(oplock);
 
 	buf->ccontext.DataOffset = cpu_to_le16(offsetof
@@ -2284,8 +2282,7 @@  smb3_parse_lease_buf(void *buf, unsigned int *epoch, char *lease_key)
 	if (lc->lcontext.LeaseFlags & SMB2_LEASE_FLAG_BREAK_IN_PROGRESS)
 		return SMB2_OPLOCK_LEVEL_NOCHANGE;
 	if (lease_key)
-		memcpy(lease_key, &lc->lcontext.LeaseKeyLow,
-		       SMB2_LEASE_KEY_SIZE);
+		memcpy(lease_key, &lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
 	return le32_to_cpu(lc->lcontext.LeaseState);
 }
 
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 810b85787c91..7608c241b1ef 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1712,7 +1712,7 @@  add_lease_context(struct TCP_Server_Info *server, struct kvec *iov,
 	struct smb2_create_req *req = iov[0].iov_base;
 	unsigned int num = *num_iovec;
 
-	iov[num].iov_base = server->ops->create_lease_buf(oplock+1, *oplock);
+	iov[num].iov_base = server->ops->create_lease_buf(*oplock);
 	if (iov[num].iov_base == NULL)
 		return -ENOMEM;
 	iov[num].iov_len = server->vals->create_lease_size;
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 824dddeee3f2..a671adcc44a6 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -678,16 +678,14 @@  struct create_context {
 #define SMB2_LEASE_KEY_SIZE 16
 
 struct lease_context {
-	__le64 LeaseKeyLow;
-	__le64 LeaseKeyHigh;
+	u8 LeaseKey[SMB2_LEASE_KEY_SIZE];
 	__le32 LeaseState;
 	__le32 LeaseFlags;
 	__le64 LeaseDuration;
 } __packed;
 
 struct lease_context_v2 {
-	__le64 LeaseKeyLow;
-	__le64 LeaseKeyHigh;
+	u8 LeaseKey[SMB2_LEASE_KEY_SIZE];
 	__le32 LeaseState;
 	__le32 LeaseFlags;
 	__le64 LeaseDuration;