linux.git, branch v4.14.260

Linux 4.14.260

2021-12-29T11:17:37+00:00

Link: https://lore.kernel.org/r/20211227151318.475251079@linuxfoundation.org
Tested-by: Linux Kernel Functional Testing 
Tested-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

phonet/pep: refuse to enable an unbound pipe

2021-12-29T11:17:37+00:00

commit 75a2f31520095600f650597c0ac41f48b5ba0068 upstream.

This ioctl() implicitly assumed that the socket was already bound to
a valid local socket name, i.e. Phonet object. If the socket was not
bound, two separate problems would occur:

1) We'd send an pipe enablement request with an invalid source object.
2) Later socket calls could BUG on the socket unexpectedly being
   connected yet not bound to a valid object.

Reported-by: syzbot+2dc91e7fc3dea88b1e8a@syzkaller.appspotmail.com
Signed-off-by: Rémi Denis-Courmont 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hamradio: improve the incomplete fix to avoid NPD

2021-12-29T11:17:37+00:00

commit b2f37aead1b82a770c48b5d583f35ec22aabb61e upstream.

The previous commit 3e0588c291d6 ("hamradio: defer ax25 kfree after
unregister_netdev") reorder the kfree operations and unregister_netdev
operation to prevent UAF.

This commit improves the previous one by also deferring the nullify of
the ax->tty pointer. Otherwise, a NULL pointer dereference bug occurs.
Partial of the stack trace is shown below.

BUG: kernel NULL pointer dereference, address: 0000000000000538
RIP: 0010:ax_xmit+0x1f9/0x400
...
Call Trace:
 dev_hard_start_xmit+0xec/0x320
 sch_direct_xmit+0xea/0x240
 __qdisc_run+0x166/0x5c0
 __dev_queue_xmit+0x2c7/0xaf0
 ax25_std_establish_data_link+0x59/0x60
 ax25_connect+0x3a0/0x500
 ? security_socket_connect+0x2b/0x40
 __sys_connect+0x96/0xc0
 ? __hrtimer_init+0xc0/0xc0
 ? common_nsleep+0x2e/0x50
 ? switch_fpu_return+0x139/0x1a0
 __x64_sys_connect+0x11/0x20
 do_syscall_64+0x33/0x40
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The crash point is shown as below

static void ax_encaps(...) {
  ...
  set_bit(TTY_DO_WRITE_WAKEUP, &ax->tty->flags); // ax->tty = NULL!
  ...
}

By placing the nullify action after the unregister_netdev, the ax->tty
pointer won't be assigned as NULL net_device framework layer is well
synchronized.

Signed-off-by: Lin Ma 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hamradio: defer ax25 kfree after unregister_netdev

2021-12-29T11:17:37+00:00

commit 3e0588c291d6ce225f2b891753ca41d45ba42469 upstream.

There is a possible race condition (use-after-free) like below

 (USE)                       |  (FREE)
ax25_sendmsg                 |
 ax25_queue_xmit             |
  dev_queue_xmit             |
   __dev_queue_xmit          |
    __dev_xmit_skb           |
     sch_direct_xmit         | ...
      xmit_one               |
       netdev_start_xmit     | tty_ldisc_kill
        __netdev_start_xmit  |  mkiss_close
         ax_xmit             |   kfree
          ax_encaps          |
                             |

Even though there are two synchronization primitives before the kfree:
1. wait_for_completion(&ax->dead). This can prevent the race with
routines from mkiss_ioctl. However, it cannot stop the routine coming
from upper layer, i.e., the ax25_sendmsg.

2. netif_stop_queue(ax->dev). It seems that this line of code aims to
halt the transmit queue but it fails to stop the routine that already
being xmit.

This patch reorder the kfree after the unregister_netdev to avoid the
possible UAF as the unregister_netdev() is well synchronized and won't
return if there is a running routine.

Signed-off-by: Lin Ma 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ax25: NPD bug when detaching AX25 device

2021-12-29T11:17:36+00:00

commit 1ade48d0c27d5da1ccf4b583d8c5fc8b534a3ac8 upstream.

The existing cleanup routine implementation is not well synchronized
with the syscall routine. When a device is detaching, below race could
occur.

static int ax25_sendmsg(...) {
  ...
  lock_sock()
  ax25 = sk_to_ax25(sk);
  if (ax25->ax25_dev == NULL) // CHECK
  ...
  ax25_queue_xmit(skb, ax25->ax25_dev->dev); // USE
  ...
}

static void ax25_kill_by_device(...) {
  ...
  if (s->ax25_dev == ax25_dev) {
    s->ax25_dev = NULL;
    ...
}

Other syscall functions like ax25_getsockopt, ax25_getname,
ax25_info_show also suffer from similar races. To fix them, this patch
introduce lock_sock() into ax25_kill_by_device in order to guarantee
that the nullify action in cleanup routine cannot proceed when another
socket request is pending.

Signed-off-by: Hanjie Wu 
Signed-off-by: Lin Ma 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hwmon: (lm90) Do not report 'busy' status bit as alarm

2021-12-29T11:17:36+00:00

commit cdc5287acad9ede121924a9c9313544b80d15842 upstream.

Bit 7 of the status register indicates that the chip is busy
doing a conversion. It does not indicate an alarm status.
Stop reporting it as alarm status bit.

Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

KVM: VMX: Fix stale docs for kvm-intel.emulate_invalid_guest_state

2021-12-29T11:17:36+00:00

commit 0ff29701ffad9a5d5a24344d8b09f3af7b96ffda upstream.

Update the documentation for kvm-intel's emulate_invalid_guest_state to
rectify the description of KVM's default behavior, and to document that
the behavior and thus parameter only applies to L1.

Fixes: a27685c33acc ("KVM: VMX: Emulate invalid guest state by default")
Signed-off-by: Sean Christopherson 
Message-Id: <20211207193006.120997-4-seanjc@google.com>
Reviewed-by: Maxim Levitsky 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_ether: fix race in setting MAC address in setup phase

2021-12-29T11:17:36+00:00

commit 890d5b40908bfd1a79be018d2d297cf9df60f4ee upstream.

When listening for notifications through netlink of a new interface being
registered, sporadically, it is possible for the MAC to be read as zero.
The zero MAC address lasts a short period of time and then switches to a
valid random MAC address.

This causes problems for netd in Android, which assumes that the interface
is malfunctioning and will not use it.

In the good case we get this log:
InterfaceController::getCfg() ifName usb0
 hwAddr 92:a8:f0:73:79:5b ipv4Addr 0.0.0.0 flags 0x1002

In the error case we get these logs:
InterfaceController::getCfg() ifName usb0
 hwAddr 00:00:00:00:00:00 ipv4Addr 0.0.0.0 flags 0x1002

netd : interfaceGetCfg("usb0")
netd : interfaceSetCfg() -> ServiceSpecificException
 (99, "[Cannot assign requested address] : ioctl() failed")

The reason for the issue is the order in which the interface is setup,
it is first registered through register_netdev() and after the MAC
address is set.

Fixed by first setting the MAC address of the net_device and after that
calling register_netdev().

Fixes: bcd4a1c40bee885e ("usb: gadget: u_ether: construct with default values and add setters/getters")
Cc: stable@vger.kernel.org
Signed-off-by: Marian Postevca 
Link: https://lore.kernel.org/r/20211204214912.17627-1-posteuca@mutex.one
Signed-off-by: Greg Kroah-Hartman

f2fs: fix to do sanity check on last xattr entry in __f2fs_setxattr()

2021-12-29T11:17:36+00:00

commit 5598b24efaf4892741c798b425d543e4bed357a1 upstream.

As Wenqing Liu reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=215235

- Overview
page fault in f2fs_setxattr() when mount and operate on corrupted image

- Reproduce
tested on kernel 5.16-rc3, 5.15.X under root

1. unzip tmp7.zip
2. ./single.sh f2fs 7

Sometimes need to run the script several times

- Kernel dump
loop0: detected capacity change from 0 to 131072
F2FS-fs (loop0): Found nat_bits in checkpoint
F2FS-fs (loop0): Mounted with checkpoint version = 7548c2ee
BUG: unable to handle page fault for address: ffffe47bc7123f48
RIP: 0010:kfree+0x66/0x320
Call Trace:
 __f2fs_setxattr+0x2aa/0xc00 [f2fs]
 f2fs_setxattr+0xfa/0x480 [f2fs]
 __f2fs_set_acl+0x19b/0x330 [f2fs]
 __vfs_removexattr+0x52/0x70
 __vfs_removexattr_locked+0xb1/0x140
 vfs_removexattr+0x56/0x100
 removexattr+0x57/0x80
 path_removexattr+0xa3/0xc0
 __x64_sys_removexattr+0x17/0x20
 do_syscall_64+0x37/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The root cause is in __f2fs_setxattr(), we missed to do sanity check on
last xattr entry, result in out-of-bound memory access during updating
inconsistent xattr data of target inode.

After the fix, it can detect such xattr inconsistency as below:

F2FS-fs (loop11): inode (7) has invalid last xattr entry, entry_size: 60676
F2FS-fs (loop11): inode (8) has corrupted xattr
F2FS-fs (loop11): inode (8) has corrupted xattr
F2FS-fs (loop11): inode (8) has invalid last xattr entry, entry_size: 47736

Cc: stable@vger.kernel.org
Reported-by: Wenqing Liu 
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim 
[delete f2fs_err() call as it's not in older kernels - gregkh]
Signed-off-by: Greg Kroah-Hartman

ARM: 9169/1: entry: fix Thumb2 bug in iWMMXt exception handling

2021-12-29T11:17:36+00:00

commit 8536a5ef886005bc443c2da9b842d69fd3d7647f upstream.

The Thumb2 version of the FP exception handling entry code treats the
register holding the CP number (R8) differently, resulting in the iWMMXT
CP number check to be incorrect.

Fix this by unifying the ARM and Thumb2 code paths, and switch the
order of the additions of the TI_USED_CP offset and the shifted CP
index.

Cc: 
Fixes: b86040a59feb ("Thumb-2: Implementation of the unified start-up and exceptions code")
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Greg Kroah-Hartman