linux-stable.git/drivers, branch linux-4.20.y Linux kernel stable tree vhost/vsock: fix vhost vsock cid hashing inconsistent 2019-03-19T12:11:56+00:00 Zha Bin zhabin@linux.alibaba.com 2019-01-08T08:07:03+00:00 9ad64a53fd0f2dbb54c80280c1bc573e71666e27 commit 7fbe078c37aba3088359c9256c1a1d0c3e39ee81 upstream. The vsock core only supports 32bit CID, but the Virtio-vsock spec define CID (dst_cid and src_cid) as u64 and the upper 32bits is reserved as zero. This inconsistency causes one bug in vhost vsock driver. The scenarios is: 0. A hash table (vhost_vsock_hash) is used to map an CID to a vsock object. And hash_min() is used to compute the hash key. hash_min() is defined as: (sizeof(val) <= 4 ? hash_32(val, bits) : hash_long(val, bits)). That means the hash algorithm has dependency on the size of macro argument 'val'. 0. In function vhost_vsock_set_cid(), a 64bit CID is passed to hash_min() to compute the hash key when inserting a vsock object into the hash table. 0. In function vhost_vsock_get(), a 32bit CID is passed to hash_min() to compute the hash key when looking up a vsock for an CID. Because the different size of the CID, hash_min() returns different hash key, thus fails to look up the vsock object for an CID. To fix this bug, we keep CID as u64 in the IOCTLs and virtio message headers, but explicitly convert u64 to u32 when deal with the hash table and vsock core. Fixes: 834e772c8db0 ("vhost/vsock: fix use-after-free in network stack callers") Link: https://github.com/stefanha/virtio/blob/vsock/trunk/content.tex Signed-off-by: Zha Bin <zhabin@linux.alibaba.com> Reviewed-by: Liu Jiang <gerry@linux.alibaba.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Shengjing Zhu <i@zhsj.me> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 7fbe078c37aba3088359c9256c1a1d0c3e39ee81 upstream.

The vsock core only supports 32bit CID, but the Virtio-vsock spec define
CID (dst_cid and src_cid) as u64 and the upper 32bits is reserved as
zero. This inconsistency causes one bug in vhost vsock driver. The
scenarios is:

  0. A hash table (vhost_vsock_hash) is used to map an CID to a vsock
  object. And hash_min() is used to compute the hash key. hash_min() is
  defined as:
  (sizeof(val) <= 4 ? hash_32(val, bits) : hash_long(val, bits)).
  That means the hash algorithm has dependency on the size of macro
  argument 'val'.
  0. In function vhost_vsock_set_cid(), a 64bit CID is passed to
  hash_min() to compute the hash key when inserting a vsock object into
  the hash table.
  0. In function vhost_vsock_get(), a 32bit CID is passed to hash_min()
  to compute the hash key when looking up a vsock for an CID.

Because the different size of the CID, hash_min() returns different hash
key, thus fails to look up the vsock object for an CID.

To fix this bug, we keep CID as u64 in the IOCTLs and virtio message
headers, but explicitly convert u64 to u32 when deal with the hash table
and vsock core.

Fixes: 834e772c8db0 ("vhost/vsock: fix use-after-free in network stack callers")
Link: https://github.com/stefanha/virtio/blob/vsock/trunk/content.tex
Signed-off-by: Zha Bin <zhabin@linux.alibaba.com>
Reviewed-by: Liu Jiang <gerry@linux.alibaba.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Shengjing Zhu <i@zhsj.me>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm: Block fb changes for async plane updates 2019-03-19T12:11:56+00:00 Nicholas Kazlauskas nicholas.kazlauskas@amd.com 2019-01-07T17:41:46+00:00 a16d17d1498abc2520e30cb3284e0a24a7e427de commit 25dc194b34dd5919dd07b8873ee338182e15df9d upstream. The prepare_fb call always happens on new_plane_state. The drm_atomic_helper_cleanup_planes checks to see if plane state pointer has changed when deciding to call cleanup_fb on either the new_plane_state or the old_plane_state. For a non-async atomic commit the state pointer is swapped, so this helper calls prepare_fb on the new_plane_state and cleanup_fb on the old_plane_state. This makes sense, since we want to prepare the framebuffer we are going to use and cleanup the the framebuffer we are no longer using. For the async atomic update helpers this differs. The async atomic update helpers perform in-place updates on the existing state. They call drm_atomic_helper_cleanup_planes but the state pointer is not swapped. This means that prepare_fb is called on the new_plane_state and cleanup_fb is called on the new_plane_state (not the old). In the case where old_plane_state->fb == new_plane_state->fb then there should be no behavioral difference between an async update and a non-async commit. But there are issues that arise when old_plane_state->fb != new_plane_state->fb. The first is that the new_plane_state->fb is immediately cleaned up after it has been prepared, so we're using a fb that we shouldn't be. The second occurs during a sequence of async atomic updates and non-async regular atomic commits. Suppose there are two framebuffers being interleaved in a double-buffering scenario, fb1 and fb2: - Async update, oldfb = NULL, newfb = fb1, prepare fb1, cleanup fb1 - Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb2 - Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2 We call cleanup_fb on fb2 twice in this example scenario, and any further use will result in use-after-free. The simple fix to this problem is to block framebuffer changes in the drm_atomic_helper_async_check function for now. v2: Move check by itself, add a FIXME (Daniel) Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Harry Wentland <harry.wentland@amd.com> Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com> Cc: <stable@vger.kernel.org> # v4.14+ Fixes: fef9df8b5945 ("drm/atomic: initial support for asynchronous plane update") Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Acked-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> Acked-by: Harry Wentland <harry.wentland@amd.com> Reviewed-by: Daniel Vetter <daniel@ffwll.ch> Signed-off-by: Harry Wentland <harry.wentland@amd.com> Link: https://patchwork.freedesktop.org/patch/275364/ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 25dc194b34dd5919dd07b8873ee338182e15df9d upstream.

The prepare_fb call always happens on new_plane_state.

The drm_atomic_helper_cleanup_planes checks to see if
plane state pointer has changed when deciding to call cleanup_fb on
either the new_plane_state or the old_plane_state.

For a non-async atomic commit the state pointer is swapped, so this
helper calls prepare_fb on the new_plane_state and cleanup_fb on the
old_plane_state. This makes sense, since we want to prepare the
framebuffer we are going to use and cleanup the the framebuffer we are
no longer using.

For the async atomic update helpers this differs. The async atomic
update helpers perform in-place updates on the existing state. They call
drm_atomic_helper_cleanup_planes but the state pointer is not swapped.
This means that prepare_fb is called on the new_plane_state and
cleanup_fb is called on the new_plane_state (not the old).

In the case where old_plane_state->fb == new_plane_state->fb then
there should be no behavioral difference between an async update
and a non-async commit. But there are issues that arise when
old_plane_state->fb != new_plane_state->fb.

The first is that the new_plane_state->fb is immediately cleaned up
after it has been prepared, so we're using a fb that we shouldn't
be.

The second occurs during a sequence of async atomic updates and
non-async regular atomic commits. Suppose there are two framebuffers
being interleaved in a double-buffering scenario, fb1 and fb2:

- Async update, oldfb = NULL, newfb = fb1, prepare fb1, cleanup fb1
- Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb2
- Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2

We call cleanup_fb on fb2 twice in this example scenario, and any
further use will result in use-after-free.

The simple fix to this problem is to block framebuffer changes
in the drm_atomic_helper_async_check function for now.

v2: Move check by itself, add a FIXME (Daniel)

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Cc: <stable@vger.kernel.org> # v4.14+
Fixes: fef9df8b5945 ("drm/atomic: initial support for asynchronous plane update")
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Acked-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Link: https://patchwork.freedesktop.org/patch/275364/
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's wrong to add len to sector_nr in raid10 reshape twice 2019-03-19T12:11:56+00:00 Xiao Ni xni@redhat.com 2019-03-08T15:52:05+00:00 41ded4f889a9e4e2cd04b5f7263501e3ec308bcb commit b761dcf1217760a42f7897c31dcb649f59b2333e upstream. In reshape_request it already adds len to sector_nr already. It's wrong to add len to sector_nr again after adding pages to bio. If there is bad block it can't copy one chunk at a time, it needs to goto read_more. Now the sector_nr is wrong. It can cause data corruption. Cc: stable@vger.kernel.org # v3.16+ Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b761dcf1217760a42f7897c31dcb649f59b2333e upstream.

In reshape_request it already adds len to sector_nr already. It's wrong to add len to
sector_nr again after adding pages to bio. If there is bad block it can't copy one chunk
at a time, it needs to goto read_more. Now the sector_nr is wrong. It can cause data
corruption.

Cc: stable@vger.kernel.org # v3.16+
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bonding: fix PACKET_ORIGDEV regression 2019-03-19T12:11:55+00:00 Michal Soltys soltys@ziu.info 2019-02-18T16:55:28+00:00 9d8945e0f17518abf764262f1ffc1f84cc4e6441 [ Upstream commit 3c963a3306eada999be5ebf4f293dfa3d3945487 ] This patch fixes a subtle PACKET_ORIGDEV regression which was a side effect of fixes introduced by: 6a9e461f6fe4 bonding: pass link-local packets to bonding master also. ... to: b89f04c61efe bonding: deliver link-local packets with skb->dev set to link that packets arrived on While 6a9e461f6fe4 restored pre-b89f04c61efe presence of link-local packets on bonding masters (which is required e.g. by linux bridges participating in spanning tree or needed for lab-like setups created with group_fwd_mask) it also caused the originating device information to be lost due to cloning. Maciej Żenczykowski proposed another solution that doesn't require packet cloning and retains original device information - instead of returning RX_HANDLER_PASS for all link-local packets it's now limited only to packets from inactive slaves. At the same time, packets passed to bonding masters retain correct information about the originating device and PACKET_ORIGDEV can be used to determine it. This elegantly solves all issues so far: - link-local packets that were removed from bonding masters - LLDP daemons being forced to explicitly bind to slave interfaces - PACKET_ORIGDEV having no effect on bond interfaces Fixes: 6a9e461f6fe4 (bonding: pass link-local packets to bonding master also.) Reported-by: Vincent Bernat <vincent@bernat.ch> Signed-off-by: Michal Soltys <soltys@ziu.info> Signed-off-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 3c963a3306eada999be5ebf4f293dfa3d3945487 ]

This patch fixes a subtle PACKET_ORIGDEV regression which was a side
effect of fixes introduced by:

6a9e461f6fe4 bonding: pass link-local packets to bonding master also.

... to:

b89f04c61efe bonding: deliver link-local packets with skb->dev set to link that packets arrived on

While 6a9e461f6fe4 restored pre-b89f04c61efe presence of link-local
packets on bonding masters (which is required e.g. by linux bridges
participating in spanning tree or needed for lab-like setups created
with group_fwd_mask) it also caused the originating device
information to be lost due to cloning.

Maciej Żenczykowski proposed another solution that doesn't require
packet cloning and retains original device information - instead of
returning RX_HANDLER_PASS for all link-local packets it's now limited
only to packets from inactive slaves.

At the same time, packets passed to bonding masters retain correct
information about the originating device and PACKET_ORIGDEV can be used
to determine it.

This elegantly solves all issues so far:

- link-local packets that were removed from bonding masters
- LLDP daemons being forced to explicitly bind to slave interfaces
- PACKET_ORIGDEV having no effect on bond interfaces

Fixes: 6a9e461f6fe4 (bonding: pass link-local packets to bonding master also.)
Reported-by: Vincent Bernat <vincent@bernat.ch>
Signed-off-by: Michal Soltys <soltys@ziu.info>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipvlan: disallow userns cap_net_admin to change global mode/flags 2019-03-19T12:11:55+00:00 Daniel Borkmann daniel@iogearbox.net 2019-02-19T23:15:30+00:00 9c68aaee71ce672c4848554f377e6f80138c7d90 [ Upstream commit 7cc9f7003a969d359f608ebb701d42cafe75b84a ] When running Docker with userns isolation e.g. --userns-remap="default" and spawning up some containers with CAP_NET_ADMIN under this realm, I noticed that link changes on ipvlan slave device inside that container can affect all devices from this ipvlan group which are in other net namespaces where the container should have no permission to make changes to, such as the init netns, for example. This effectively allows to undo ipvlan private mode and switch globally to bridge mode where slaves can communicate directly without going through hostns, or it allows to switch between global operation mode (l2/l3/l3s) for everyone bound to the given ipvlan master device. libnetwork plugin here is creating an ipvlan master and ipvlan slave in hostns and a slave each that is moved into the container's netns upon creation event. * In hostns: # ip -d a [...] 8: cilium_host@bond0: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535 ipvlan mode l3 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 inet 10.41.0.1/32 scope link cilium_host valid_lft forever preferred_lft forever [...] * Spawn container & change ipvlan mode setting inside of it: # docker run -dt --cap-add=NET_ADMIN --network cilium-net --name client -l app=test cilium/netperf 9fff485d69dcb5ce37c9e33ca20a11ccafc236d690105aadbfb77e4f4170879c # docker exec -ti client ip -d a [...] 10: cilium0@if4: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535 ipvlan mode l3 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 inet 10.41.197.43/32 brd 10.41.197.43 scope global cilium0 valid_lft forever preferred_lft forever # docker exec -ti client ip link change link cilium0 name cilium0 type ipvlan mode l2 # docker exec -ti client ip -d a [...] 10: cilium0@if4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535 ipvlan mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 inet 10.41.197.43/32 brd 10.41.197.43 scope global cilium0 valid_lft forever preferred_lft forever * In hostns (mode switched to l2): # ip -d a [...] 8: cilium_host@bond0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535 ipvlan mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 inet 10.41.0.1/32 scope link cilium_host valid_lft forever preferred_lft forever [...] Same l3 -> l2 switch would also happen by creating another slave inside the container's network namespace when specifying the existing cilium0 link to derive the actual (bond0) master: # docker exec -ti client ip link add link cilium0 name cilium1 type ipvlan mode l2 # docker exec -ti client ip -d a [...] 2: cilium1@if4: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535 ipvlan mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 10: cilium0@if4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535 ipvlan mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 inet 10.41.197.43/32 brd 10.41.197.43 scope global cilium0 valid_lft forever preferred_lft forever * In hostns: # ip -d a [...] 8: cilium_host@bond0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535 ipvlan mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 inet 10.41.0.1/32 scope link cilium_host valid_lft forever preferred_lft forever [...] One way to mitigate it is to check CAP_NET_ADMIN permissions of the ipvlan master device's ns, and only then allow to change mode or flags for all devices bound to it. Above two cases are then disallowed after the patch. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Mahesh Bandewar <maheshb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 7cc9f7003a969d359f608ebb701d42cafe75b84a ]

When running Docker with userns isolation e.g. --userns-remap="default"
and spawning up some containers with CAP_NET_ADMIN under this realm, I
noticed that link changes on ipvlan slave device inside that container
can affect all devices from this ipvlan group which are in other net
namespaces where the container should have no permission to make changes
to, such as the init netns, for example.

This effectively allows to undo ipvlan private mode and switch globally to
bridge mode where slaves can communicate directly without going through
hostns, or it allows to switch between global operation mode (l2/l3/l3s)
for everyone bound to the given ipvlan master device. libnetwork plugin
here is creating an ipvlan master and ipvlan slave in hostns and a slave
each that is moved into the container's netns upon creation event.

* In hostns:

  # ip -d a
  [...]
  8: cilium_host@bond0: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
     link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535
     ipvlan  mode l3 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
     inet 10.41.0.1/32 scope link cilium_host
       valid_lft forever preferred_lft forever
  [...]

* Spawn container & change ipvlan mode setting inside of it:

  # docker run -dt --cap-add=NET_ADMIN --network cilium-net --name client -l app=test cilium/netperf
  9fff485d69dcb5ce37c9e33ca20a11ccafc236d690105aadbfb77e4f4170879c

  # docker exec -ti client ip -d a
  [...]
  10: cilium0@if4: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
      link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535
      ipvlan  mode l3 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
      inet 10.41.197.43/32 brd 10.41.197.43 scope global cilium0
         valid_lft forever preferred_lft forever

  # docker exec -ti client ip link change link cilium0 name cilium0 type ipvlan mode l2

  # docker exec -ti client ip -d a
  [...]
  10: cilium0@if4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
      link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535
      ipvlan  mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
      inet 10.41.197.43/32 brd 10.41.197.43 scope global cilium0
         valid_lft forever preferred_lft forever

* In hostns (mode switched to l2):

  # ip -d a
  [...]
  8: cilium_host@bond0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
      link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535
      ipvlan  mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
      inet 10.41.0.1/32 scope link cilium_host
         valid_lft forever preferred_lft forever
  [...]

Same l3 -> l2 switch would also happen by creating another slave inside
the container's network namespace when specifying the existing cilium0
link to derive the actual (bond0) master:

  # docker exec -ti client ip link add link cilium0 name cilium1 type ipvlan mode l2

  # docker exec -ti client ip -d a
  [...]
  2: cilium1@if4: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
      link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535
      ipvlan  mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
  10: cilium0@if4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
      link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535
      ipvlan  mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
      inet 10.41.197.43/32 brd 10.41.197.43 scope global cilium0
         valid_lft forever preferred_lft forever

* In hostns:

  # ip -d a
  [...]
  8: cilium_host@bond0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
      link/ether 0c:c4:7a:e1:3d:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 65535
      ipvlan  mode l2 bridge numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
      inet 10.41.0.1/32 scope link cilium_host
         valid_lft forever preferred_lft forever
  [...]

One way to mitigate it is to check CAP_NET_ADMIN permissions of
the ipvlan master device's ns, and only then allow to change
mode or flags for all devices bound to it. Above two cases are
then disallowed after the patch.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
team: use operstate consistently for linkup 2019-03-19T12:11:55+00:00 George Wilkie gwilkie@vyatta.att-mail.com 2019-02-20T08:19:11+00:00 a19b996dd7a7048ee25c942692f2acde339b5205 [ Upstream commit 8c7a77267eec81dd81af8412f29e50c0b1082548 ] When a port is added to a team, its initial state is derived from netif_carrier_ok rather than netif_oper_up. If it is carrier up but operationally down at the time of being added, the port state.linkup will be set prematurely. port state.linkup should be set consistently using netif_oper_up rather than netif_carrier_ok. Fixes: f1d22a1e0595 ("team: account for oper state") Signed-off-by: George Wilkie <gwilkie@vyatta.att-mail.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 8c7a77267eec81dd81af8412f29e50c0b1082548 ]

When a port is added to a team, its initial state is derived
from netif_carrier_ok rather than netif_oper_up.
If it is carrier up but operationally down at the time of being
added, the port state.linkup will be set prematurely.
port state.linkup should be set consistently using
netif_oper_up rather than netif_carrier_ok.

Fixes: f1d22a1e0595 ("team: account for oper state")
Signed-off-by: George Wilkie <gwilkie@vyatta.att-mail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mdio_bus: Fix use-after-free on device_register fails 2019-03-19T12:11:54+00:00 YueHaibing yuehaibing@huawei.com 2019-02-21T14:42:01+00:00 776c7c946109734ef210df311dd7a322941dafb4 [ Upstream commit 6ff7b060535e87c2ae14dd8548512abfdda528fb ] KASAN has found use-after-free in fixed_mdio_bus_init, commit 0c692d07842a ("drivers/net/phy/mdio_bus.c: call put_device on device_register() failure") call put_device() while device_register() fails,give up the last reference to the device and allow mdiobus_release to be executed ,kfreeing the bus. However in most drives, mdiobus_free be called to free the bus while mdiobus_register fails. use-after-free occurs when access bus again, this patch revert it to let mdiobus_free free the bus. KASAN report details as below: BUG: KASAN: use-after-free in mdiobus_free+0x85/0x90 drivers/net/phy/mdio_bus.c:482 Read of size 4 at addr ffff8881dc824d78 by task syz-executor.0/3524 CPU: 1 PID: 3524 Comm: syz-executor.0 Not tainted 5.0.0-rc7+ #45 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xfa/0x1ce lib/dump_stack.c:113 print_address_description+0x65/0x270 mm/kasan/report.c:187 kasan_report+0x149/0x18d mm/kasan/report.c:317 mdiobus_free+0x85/0x90 drivers/net/phy/mdio_bus.c:482 fixed_mdio_bus_init+0x283/0x1000 [fixed_phy] ? 0xffffffffc0e40000 ? 0xffffffffc0e40000 ? 0xffffffffc0e40000 do_one_initcall+0xfa/0x5ca init/main.c:887 do_init_module+0x204/0x5f6 kernel/module.c:3460 load_module+0x66b2/0x8570 kernel/module.c:3808 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x462e99 Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6215c19c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007f6215c19c70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6215c1a6bc R13: 00000000004bcefb R14: 00000000006f7030 R15: 0000000000000004 Allocated by task 3524: set_track mm/kasan/common.c:85 [inline] __kasan_kmalloc.constprop.3+0xa0/0xd0 mm/kasan/common.c:496 kmalloc include/linux/slab.h:545 [inline] kzalloc include/linux/slab.h:740 [inline] mdiobus_alloc_size+0x54/0x1b0 drivers/net/phy/mdio_bus.c:143 fixed_mdio_bus_init+0x163/0x1000 [fixed_phy] do_one_initcall+0xfa/0x5ca init/main.c:887 do_init_module+0x204/0x5f6 kernel/module.c:3460 load_module+0x66b2/0x8570 kernel/module.c:3808 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 3524: set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x130/0x180 mm/kasan/common.c:458 slab_free_hook mm/slub.c:1409 [inline] slab_free_freelist_hook mm/slub.c:1436 [inline] slab_free mm/slub.c:2986 [inline] kfree+0xe1/0x270 mm/slub.c:3938 device_release+0x78/0x200 drivers/base/core.c:919 kobject_cleanup lib/kobject.c:662 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:67 [inline] kobject_put+0x146/0x240 lib/kobject.c:708 put_device+0x1c/0x30 drivers/base/core.c:2060 __mdiobus_register+0x483/0x560 drivers/net/phy/mdio_bus.c:382 fixed_mdio_bus_init+0x26b/0x1000 [fixed_phy] do_one_initcall+0xfa/0x5ca init/main.c:887 do_init_module+0x204/0x5f6 kernel/module.c:3460 load_module+0x66b2/0x8570 kernel/module.c:3808 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8881dc824c80 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 248 bytes inside of 2048-byte region [ffff8881dc824c80, ffff8881dc825480) The buggy address belongs to the page: page:ffffea0007720800 count:1 mapcount:0 mapping:ffff8881f6c02800 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000010200(slab|head) raw: 02fffc0000010200 0000000000000000 0000000500000001 ffff8881f6c02800 raw: 0000000000000000 00000000800f000f 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881dc824c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881dc824c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881dc824d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881dc824d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881dc824e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 0c692d07842a ("drivers/net/phy/mdio_bus.c: call put_device on device_register() failure") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 6ff7b060535e87c2ae14dd8548512abfdda528fb ]

KASAN has found use-after-free in fixed_mdio_bus_init,
commit 0c692d07842a ("drivers/net/phy/mdio_bus.c: call
put_device on device_register() failure") call put_device()
while device_register() fails,give up the last reference
to the device and allow mdiobus_release to be executed
,kfreeing the bus. However in most drives, mdiobus_free
be called to free the bus while mdiobus_register fails.
use-after-free occurs when access bus again, this patch
revert it to let mdiobus_free free the bus.

KASAN report details as below:

BUG: KASAN: use-after-free in mdiobus_free+0x85/0x90 drivers/net/phy/mdio_bus.c:482
Read of size 4 at addr ffff8881dc824d78 by task syz-executor.0/3524

CPU: 1 PID: 3524 Comm: syz-executor.0 Not tainted 5.0.0-rc7+ #45
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xfa/0x1ce lib/dump_stack.c:113
 print_address_description+0x65/0x270 mm/kasan/report.c:187
 kasan_report+0x149/0x18d mm/kasan/report.c:317
 mdiobus_free+0x85/0x90 drivers/net/phy/mdio_bus.c:482
 fixed_mdio_bus_init+0x283/0x1000 [fixed_phy]
 ? 0xffffffffc0e40000
 ? 0xffffffffc0e40000
 ? 0xffffffffc0e40000
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x462e99
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6215c19c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00007f6215c19c70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6215c1a6bc
R13: 00000000004bcefb R14: 00000000006f7030 R15: 0000000000000004

Allocated by task 3524:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc.constprop.3+0xa0/0xd0 mm/kasan/common.c:496
 kmalloc include/linux/slab.h:545 [inline]
 kzalloc include/linux/slab.h:740 [inline]
 mdiobus_alloc_size+0x54/0x1b0 drivers/net/phy/mdio_bus.c:143
 fixed_mdio_bus_init+0x163/0x1000 [fixed_phy]
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 3524:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:458
 slab_free_hook mm/slub.c:1409 [inline]
 slab_free_freelist_hook mm/slub.c:1436 [inline]
 slab_free mm/slub.c:2986 [inline]
 kfree+0xe1/0x270 mm/slub.c:3938
 device_release+0x78/0x200 drivers/base/core.c:919
 kobject_cleanup lib/kobject.c:662 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:67 [inline]
 kobject_put+0x146/0x240 lib/kobject.c:708
 put_device+0x1c/0x30 drivers/base/core.c:2060
 __mdiobus_register+0x483/0x560 drivers/net/phy/mdio_bus.c:382
 fixed_mdio_bus_init+0x26b/0x1000 [fixed_phy]
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881dc824c80
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 248 bytes inside of
 2048-byte region [ffff8881dc824c80, ffff8881dc825480)
The buggy address belongs to the page:
page:ffffea0007720800 count:1 mapcount:0 mapping:ffff8881f6c02800 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000010200(slab|head)
raw: 02fffc0000010200 0000000000000000 0000000500000001 ffff8881f6c02800
raw: 0000000000000000 00000000800f000f 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881dc824c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881dc824c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881dc824d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                                ^
 ffff8881dc824d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881dc824e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 0c692d07842a ("drivers/net/phy/mdio_bus.c: call put_device on device_register() failure")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/mlx4_core: Fix qp mtt size calculation 2019-03-19T12:11:54+00:00 Jack Morgenstein jackm@dev.mellanox.co.il 2019-03-12T15:05:49+00:00 92ebedf32fb788c9a163e87a2198df1cf2fb7061 [ Upstream commit 8511a653e9250ef36b95803c375a7be0e2edb628 ] Calculation of qp mtt size (in function mlx4_RST2INIT_wrapper) ultimately depends on function roundup_pow_of_two. If the amount of memory required by the QP is less than one page, roundup_pow_of_two is called with argument zero. In this case, the roundup_pow_of_two result is undefined. Calling roundup_pow_of_two with a zero argument resulted in the following stack trace: UBSAN: Undefined behaviour in ./include/linux/log2.h:61:13 shift exponent 64 is too large for 64-bit type 'long unsigned int' CPU: 4 PID: 26939 Comm: rping Tainted: G OE 4.19.0-rc1 Hardware name: Supermicro X9DR3-F/X9DR3-F, BIOS 3.2a 07/09/2015 Call Trace: dump_stack+0x9a/0xeb ubsan_epilogue+0x9/0x7c __ubsan_handle_shift_out_of_bounds+0x254/0x29d ? __ubsan_handle_load_invalid_value+0x180/0x180 ? debug_show_all_locks+0x310/0x310 ? sched_clock+0x5/0x10 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0x18/0x260 ? find_held_lock+0x35/0x1e0 ? mlx4_RST2INIT_QP_wrapper+0xfb1/0x1440 [mlx4_core] mlx4_RST2INIT_QP_wrapper+0xfb1/0x1440 [mlx4_core] Fix this by explicitly testing for zero, and returning one if the argument is zero (assuming that the next higher power of 2 in this case should be one). Fixes: c82e9aa0a8bc ("mlx4_core: resource tracking for HCA resources used by guests") Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 8511a653e9250ef36b95803c375a7be0e2edb628 ]

Calculation of qp mtt size (in function mlx4_RST2INIT_wrapper)
ultimately depends on function roundup_pow_of_two.

If the amount of memory required by the QP is less than one page,
roundup_pow_of_two is called with argument zero.  In this case, the
roundup_pow_of_two result is undefined.

Calling roundup_pow_of_two with a zero argument resulted in the
following stack trace:

UBSAN: Undefined behaviour in ./include/linux/log2.h:61:13
shift exponent 64 is too large for 64-bit type 'long unsigned int'
CPU: 4 PID: 26939 Comm: rping Tainted: G OE 4.19.0-rc1
Hardware name: Supermicro X9DR3-F/X9DR3-F, BIOS 3.2a 07/09/2015
Call Trace:
dump_stack+0x9a/0xeb
ubsan_epilogue+0x9/0x7c
__ubsan_handle_shift_out_of_bounds+0x254/0x29d
? __ubsan_handle_load_invalid_value+0x180/0x180
? debug_show_all_locks+0x310/0x310
? sched_clock+0x5/0x10
? sched_clock+0x5/0x10
? sched_clock_cpu+0x18/0x260
? find_held_lock+0x35/0x1e0
? mlx4_RST2INIT_QP_wrapper+0xfb1/0x1440 [mlx4_core]
mlx4_RST2INIT_QP_wrapper+0xfb1/0x1440 [mlx4_core]

Fix this by explicitly testing for zero, and returning one if the
argument is zero (assuming that the next higher power of 2 in this case
should be one).

Fixes: c82e9aa0a8bc ("mlx4_core: resource tracking for HCA resources used by guests")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/mlx4_core: Fix locking in SRIOV mode when switching between events and polling 2019-03-19T12:11:54+00:00 Jack Morgenstein jackm@dev.mellanox.co.il 2019-03-12T15:05:48+00:00 d4abbbbf77d21b22cb5c3536dbc6b8478c258679 [ Upstream commit c07d27927f2f2e96fcd27bb9fb330c9ea65612d0 ] In procedures mlx4_cmd_use_events() and mlx4_cmd_use_polling(), we need to guarantee that there are no FW commands in progress on the comm channel (for VFs) or wrapped FW commands (on the PF) when SRIOV is active. We do this by also taking the slave_cmd_mutex when SRIOV is active. This is especially important when switching from event to polling, since we free the command-context array during the switch. If there are FW commands in progress (e.g., waiting for a completion event), the completion event handler will access freed memory. Since the decision to use comm_wait or comm_poll is taken before grabbing the event_sem/poll_sem in mlx4_comm_cmd_wait/poll, we must take the slave_cmd_mutex as well (to guarantee that the decision to use events or polling and the call to the appropriate cmd function are atomic). Fixes: a7e1f04905e5 ("net/mlx4_core: Fix deadlock when switching between polling and event fw commands") Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit c07d27927f2f2e96fcd27bb9fb330c9ea65612d0 ]

In procedures mlx4_cmd_use_events() and mlx4_cmd_use_polling(), we need to
guarantee that there are no FW commands in progress on the comm channel
(for VFs) or wrapped FW commands (on the PF) when SRIOV is active.

We do this by also taking the slave_cmd_mutex when SRIOV is active.

This is especially important when switching from event to polling, since we
free the command-context array during the switch.  If there are FW commands
in progress (e.g., waiting for a completion event), the completion event
handler will access freed memory.

Since the decision to use comm_wait or comm_poll is taken before grabbing
the event_sem/poll_sem in mlx4_comm_cmd_wait/poll, we must take the
slave_cmd_mutex as well (to guarantee that the decision to use events or
polling and the call to the appropriate cmd function are atomic).

Fixes: a7e1f04905e5 ("net/mlx4_core: Fix deadlock when switching between polling and event fw commands")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/mlx4_core: Fix reset flow when in command polling mode 2019-03-19T12:11:54+00:00 Jack Morgenstein jackm@dev.mellanox.co.il 2019-03-12T15:05:47+00:00 323a6123330fd484d6ec7b941bf7a1f916d22191 [ Upstream commit e15ce4b8d11227007577e6dc1364d288b8874fbe ] As part of unloading a device, the driver switches from FW command event mode to FW command polling mode. Part of switching over to polling mode is freeing the command context array memory (unfortunately, currently, without NULLing the command context array pointer). The reset flow calls "complete" to complete all outstanding fw commands (if we are in event mode). The check for event vs. polling mode here is to test if the command context array pointer is NULL. If the reset flow is activated after the switch to polling mode, it will attempt (incorrectly) to complete all the commands in the context array -- because the pointer was not NULLed when the driver switched over to polling mode. As a result, we have a use-after-free situation, which results in a kernel crash. For example: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff876c4a8e>] __wake_up_common+0x2e/0x90 PGD 0 Oops: 0000 [#1] SMP Modules linked in: netconsole nfsv3 nfs_acl nfs lockd grace ... CPU: 2 PID: 940 Comm: kworker/2:3 Kdump: loaded Not tainted 3.10.0-862.el7.x86_64 #1 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006 04/28/2016 Workqueue: events hv_eject_device_work [pci_hyperv] task: ffff8d1734ca0fd0 ti: ffff8d17354bc000 task.ti: ffff8d17354bc000 RIP: 0010:[<ffffffff876c4a8e>] [<ffffffff876c4a8e>] __wake_up_common+0x2e/0x90 RSP: 0018:ffff8d17354bfa38 EFLAGS: 00010082 RAX: 0000000000000000 RBX: ffff8d17362d42c8 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8d17362d42c8 RBP: ffff8d17354bfa70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000298 R11: ffff8d173610e000 R12: ffff8d17362d42d0 R13: 0000000000000246 R14: 0000000000000000 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff8d1802680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000f16d8000 CR4: 00000000001406e0 Call Trace: [<ffffffff876c7adc>] complete+0x3c/0x50 [<ffffffffc04242f0>] mlx4_cmd_wake_completions+0x70/0x90 [mlx4_core] [<ffffffffc041e7b1>] mlx4_enter_error_state+0xe1/0x380 [mlx4_core] [<ffffffffc041fa4b>] mlx4_comm_cmd+0x29b/0x360 [mlx4_core] [<ffffffffc041ff51>] __mlx4_cmd+0x441/0x920 [mlx4_core] [<ffffffff877f62b1>] ? __slab_free+0x81/0x2f0 [<ffffffff87951384>] ? __radix_tree_lookup+0x84/0xf0 [<ffffffffc043a8eb>] mlx4_free_mtt_range+0x5b/0xb0 [mlx4_core] [<ffffffffc043a957>] mlx4_mtt_cleanup+0x17/0x20 [mlx4_core] [<ffffffffc04272c7>] mlx4_free_eq+0xa7/0x1c0 [mlx4_core] [<ffffffffc042803e>] mlx4_cleanup_eq_table+0xde/0x130 [mlx4_core] [<ffffffffc0433e08>] mlx4_unload_one+0x118/0x300 [mlx4_core] [<ffffffffc0434191>] mlx4_remove_one+0x91/0x1f0 [mlx4_core] The fix is to set the command context array pointer to NULL after freeing the array. Fixes: f5aef5aa3506 ("net/mlx4_core: Activate reset flow upon fatal command cases") Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit e15ce4b8d11227007577e6dc1364d288b8874fbe ]

As part of unloading a device, the driver switches from
FW command event mode to FW command polling mode.

Part of switching over to polling mode is freeing the command context array
memory (unfortunately, currently, without NULLing the command context array
pointer).

The reset flow calls "complete" to complete all outstanding fw commands
(if we are in event mode). The check for event vs. polling mode here
is to test if the command context array pointer is NULL.

If the reset flow is activated after the switch to polling mode, it will
attempt (incorrectly) to complete all the commands in the context array --
because the pointer was not NULLed when the driver switched over to polling
mode.

As a result, we have a use-after-free situation, which results in a
kernel crash.

For example:
BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff876c4a8e>] __wake_up_common+0x2e/0x90
PGD 0
Oops: 0000 [#1] SMP
Modules linked in: netconsole nfsv3 nfs_acl nfs lockd grace ...
CPU: 2 PID: 940 Comm: kworker/2:3 Kdump: loaded Not tainted 3.10.0-862.el7.x86_64 #1
Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006  04/28/2016
Workqueue: events hv_eject_device_work [pci_hyperv]
task: ffff8d1734ca0fd0 ti: ffff8d17354bc000 task.ti: ffff8d17354bc000
RIP: 0010:[<ffffffff876c4a8e>]  [<ffffffff876c4a8e>] __wake_up_common+0x2e/0x90
RSP: 0018:ffff8d17354bfa38  EFLAGS: 00010082
RAX: 0000000000000000 RBX: ffff8d17362d42c8 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8d17362d42c8
RBP: ffff8d17354bfa70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000298 R11: ffff8d173610e000 R12: ffff8d17362d42d0
R13: 0000000000000246 R14: 0000000000000000 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8d1802680000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000f16d8000 CR4: 00000000001406e0
Call Trace:
 [<ffffffff876c7adc>] complete+0x3c/0x50
 [<ffffffffc04242f0>] mlx4_cmd_wake_completions+0x70/0x90 [mlx4_core]
 [<ffffffffc041e7b1>] mlx4_enter_error_state+0xe1/0x380 [mlx4_core]
 [<ffffffffc041fa4b>] mlx4_comm_cmd+0x29b/0x360 [mlx4_core]
 [<ffffffffc041ff51>] __mlx4_cmd+0x441/0x920 [mlx4_core]
 [<ffffffff877f62b1>] ? __slab_free+0x81/0x2f0
 [<ffffffff87951384>] ? __radix_tree_lookup+0x84/0xf0
 [<ffffffffc043a8eb>] mlx4_free_mtt_range+0x5b/0xb0 [mlx4_core]
 [<ffffffffc043a957>] mlx4_mtt_cleanup+0x17/0x20 [mlx4_core]
 [<ffffffffc04272c7>] mlx4_free_eq+0xa7/0x1c0 [mlx4_core]
 [<ffffffffc042803e>] mlx4_cleanup_eq_table+0xde/0x130 [mlx4_core]
 [<ffffffffc0433e08>] mlx4_unload_one+0x118/0x300 [mlx4_core]
 [<ffffffffc0434191>] mlx4_remove_one+0x91/0x1f0 [mlx4_core]

The fix is to set the command context array pointer to NULL after freeing
the array.

Fixes: f5aef5aa3506 ("net/mlx4_core: Activate reset flow upon fatal command cases")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>