linux-stable.git/net/mpls, branch v6.2 Linux kernel stable tree net: mpls: fix stale pointer if allocation fails during device rename 2023-02-15T10:26:37+00:00 Jakub Kicinski kuba@kernel.org 2023-02-14T06:53:55+00:00 fda6c89fe3d9aca073495a664e1d5aea28cd4377 lianhui reports that when MPLS fails to register the sysctl table under new location (during device rename) the old pointers won't get overwritten and may be freed again (double free). Handle this gracefully. The best option would be unregistering the MPLS from the device completely on failure, but unfortunately mpls_ifdown() can fail. So failing fully is also unreliable. Another option is to register the new table first then only remove old one if the new one succeeds. That requires more code, changes order of notifications and two tables may be visible at the same time. sysctl point is not used in the rest of the code - set to NULL on failures and skip unregister if already NULL. Reported-by: lianhui tang <bluetlh@gmail.com> Fixes: 0fae3bf018d9 ("mpls: handle device renames for per-device sysctls") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
lianhui reports that when MPLS fails to register the sysctl table
under new location (during device rename) the old pointers won't
get overwritten and may be freed again (double free).

Handle this gracefully. The best option would be unregistering
the MPLS from the device completely on failure, but unfortunately
mpls_ifdown() can fail. So failing fully is also unreliable.

Another option is to register the new table first then only
remove old one if the new one succeeds. That requires more
code, changes order of notifications and two tables may be
visible at the same time.

sysctl point is not used in the rest of the code - set to NULL
on failures and skip unregister if already NULL.

Reported-by: lianhui tang <bluetlh@gmail.com>
Fixes: 0fae3bf018d9 ("mpls: handle device renames for per-device sysctls")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: Remove the obsolte u64_stats_fetch_*_irq() users (net). 2022-10-29T03:13:54+00:00 Thomas Gleixner tglx@linutronix.de 2022-10-26T13:22:15+00:00 d120d1a63b2c484d6175873d8ee736a633f74b70 Now that the 32bit UP oddity is gone and 32bit uses always a sequence count, there is no need for the fetch_irq() variants anymore. Convert to the regular interface. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Now that the 32bit UP oddity is gone and 32bit uses always a sequence
count, there is no need for the fetch_irq() variants anymore.

Convert to the regular interface.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: Use u64_stats_fetch_begin_irq() for stats fetch. 2022-08-29T12:02:27+00:00 Sebastian Andrzej Siewior bigeasy@linutronix.de 2022-08-25T11:36:45+00:00 278d3ba61563ceed3cb248383ced19e14ec7bc1f On 32bit-UP u64_stats_fetch_begin() disables only preemption. If the reader is in preemptible context and the writer side (u64_stats_update_begin*()) runs in an interrupt context (IRQ or softirq) then the writer can update the stats during the read operation. This update remains undetected. Use u64_stats_fetch_begin_irq() to ensure the stats fetch on 32bit-UP are not interrupted by a writer. 32bit-SMP remains unaffected by this change. Cc: "David S. Miller" <davem@davemloft.net> Cc: Catherine Sullivan <csully@google.com> Cc: David Awogbemila <awogbemila@google.com> Cc: Dimitris Michailidis <dmichail@fungible.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Jeroen de Borst <jeroendb@google.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Simon Horman <simon.horman@corigine.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org Cc: oss-drivers@corigine.com Cc: stable@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
On 32bit-UP u64_stats_fetch_begin() disables only preemption. If the
reader is in preemptible context and the writer side
(u64_stats_update_begin*()) runs in an interrupt context (IRQ or
softirq) then the writer can update the stats during the read operation.
This update remains undetected.

Use u64_stats_fetch_begin_irq() to ensure the stats fetch on 32bit-UP
are not interrupted by a writer. 32bit-SMP remains unaffected by this
change.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Catherine Sullivan <csully@google.com>
Cc: David Awogbemila <awogbemila@google.com>
Cc: Dimitris Michailidis <dmichail@fungible.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jeroen de Borst <jeroendb@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <simon.horman@corigine.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: oss-drivers@corigine.com
Cc: stable@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: mpls: fix memdup.cocci warning 2022-04-08T04:06:41+00:00 GONG, Ruiqi gongruiqi1@huawei.com 2022-04-06T11:46:29+00:00 27a5a5685d373cd8c18b1d83f42a83e5a2f93e6c Simply use kmemdup instead of explicitly allocating and copying memory. Generated by: scripts/coccinelle/api/memdup.cocci Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com> Link: https://lore.kernel.org/r/20220406114629.182833-1-gongruiqi1@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Simply use kmemdup instead of explicitly allocating and copying memory.

Generated by: scripts/coccinelle/api/memdup.cocci

Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
Link: https://lore.kernel.org/r/20220406114629.182833-1-gongruiqi1@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: mpls: Fix GCC 12 warning 2022-02-10T15:29:39+00:00 Victor Erminpour victor.erminpour@oracle.com 2022-02-10T00:28:38+00:00 c4416f5c2eb3ed48dfba265e628a6e52da962f03 When building with automatic stack variable initialization, GCC 12 complains about variables defined outside of switch case statements. Move the variable outside the switch, which silences the warning: ./net/mpls/af_mpls.c:1624:21: error: statement will never be executed [-Werror=switch-unreachable] 1624 | int err; | ^~~ Signed-off-by: Victor Erminpour <victor.erminpour@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
When building with automatic stack variable initialization, GCC 12
complains about variables defined outside of switch case statements.
Move the variable outside the switch, which silences the warning:

./net/mpls/af_mpls.c:1624:21: error: statement will never be executed [-Werror=switch-unreachable]
  1624 |                 int err;
       |                     ^~~

Signed-off-by: Victor Erminpour <victor.erminpour@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-12-02T19:44:56+00:00 Jakub Kicinski kuba@kernel.org 2021-12-02T19:44:56+00:00 fc993be36f9ea7fc286d84d8471a1a20e871aad4 Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: mpls: Make for_nexthops iterator const 2021-11-29T12:46:52+00:00 Benjamin Poirier bpoirier@nvidia.com 2021-11-29T06:23:16+00:00 f05b0b97335be1b4f9f1f1044eb617f4e12c681e There are separate for_nexthops and change_nexthops iterators. The for_nexthops variant should use const. Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
There are separate for_nexthops and change_nexthops iterators. The
for_nexthops variant should use const.

Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: mpls: Remove duplicate variable from iterator macro 2021-11-29T12:46:52+00:00 Benjamin Poirier bpoirier@nvidia.com 2021-11-29T06:23:15+00:00 69d9c0d07726b6d49cf8b2609226b7b88a0f3d51 __nh is just a copy of nh with a different type. Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
__nh is just a copy of nh with a different type.

Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: mpls: Remove rcu protection from nh_dev 2021-11-29T12:39:42+00:00 Benjamin Poirier bpoirier@nvidia.com 2021-11-29T06:15:06+00:00 189168181bb67825a14e8083d1503cfdc2891ebf Following the previous commit, nh_dev can no longer be accessed and modified concurrently. Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Following the previous commit, nh_dev can no longer be accessed and
modified concurrently.

Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: mpls: Fix notifications when deleting a device 2021-11-29T12:39:42+00:00 Benjamin Poirier bpoirier@nvidia.com 2021-11-29T06:15:05+00:00 7d4741eacdefa5f0475431645b56baf00784df1f There are various problems related to netlink notifications for mpls route changes in response to interfaces being deleted: * delete interface of only nexthop DELROUTE notification is missing RTA_OIF attribute * delete interface of non-last nexthop NEWROUTE notification is missing entirely * delete interface of last nexthop DELROUTE notification is missing nexthop All of these problems stem from the fact that existing routes are modified in-place before sending a notification. Restructure mpls_ifdown() to avoid changing the route in the DELROUTE cases and to create a copy in the NEWROUTE case. Fixes: f8efb73c97e2 ("mpls: multipath route support") Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
There are various problems related to netlink notifications for mpls route
changes in response to interfaces being deleted:
* delete interface of only nexthop
	DELROUTE notification is missing RTA_OIF attribute
* delete interface of non-last nexthop
	NEWROUTE notification is missing entirely
* delete interface of last nexthop
	DELROUTE notification is missing nexthop

All of these problems stem from the fact that existing routes are modified
in-place before sending a notification. Restructure mpls_ifdown() to avoid
changing the route in the DELROUTE cases and to create a copy in the
NEWROUTE case.

Fixes: f8efb73c97e2 ("mpls: multipath route support")
Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>