linux.git/include/net, branch v6.5-rc7 Linux kernel source tree sock: Fix misuse of sk_under_memory_pressure() 2023-08-17T18:34:36+00:00 Abel Wu wuyun.abel@bytedance.com 2023-08-16T09:12:22+00:00 2d0c88e84e483982067a82073f6125490ddf3614 The status of global socket memory pressure is updated when: a) __sk_mem_raise_allocated(): enter: sk_memory_allocated(sk) > sysctl_mem[1] leave: sk_memory_allocated(sk) <= sysctl_mem[0] b) __sk_mem_reduce_allocated(): leave: sk_under_memory_pressure(sk) && sk_memory_allocated(sk) < sysctl_mem[0] So the conditions of leaving global pressure are inconstant, which may lead to the situation that one pressured net-memcg prevents the global pressure from being cleared when there is indeed no global pressure, thus the global constrains are still in effect unexpectedly on the other sockets. This patch fixes this by ignoring the net-memcg's pressure when deciding whether should leave global memory pressure. Fixes: e1aab161e013 ("socket: initial cgroup code.") Signed-off-by: Abel Wu <wuyun.abel@bytedance.com> Acked-by: Shakeel Butt <shakeelb@google.com> Link: https://lore.kernel.org/r/20230816091226.1542-1-wuyun.abel@bytedance.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
The status of global socket memory pressure is updated when:

  a) __sk_mem_raise_allocated():

	enter: sk_memory_allocated(sk) >  sysctl_mem[1]
	leave: sk_memory_allocated(sk) <= sysctl_mem[0]

  b) __sk_mem_reduce_allocated():

	leave: sk_under_memory_pressure(sk) &&
		sk_memory_allocated(sk) < sysctl_mem[0]

So the conditions of leaving global pressure are inconstant, which
may lead to the situation that one pressured net-memcg prevents the
global pressure from being cleared when there is indeed no global
pressure, thus the global constrains are still in effect unexpectedly
on the other sockets.

This patch fixes this by ignoring the net-memcg's pressure when
deciding whether should leave global memory pressure.

Fixes: e1aab161e013 ("socket: initial cgroup code.")
Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Link: https://lore.kernel.org/r/20230816091226.1542-1-wuyun.abel@bytedance.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge tag 'nf-23-08-16' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf 2023-08-16T10:11:24+00:00 David S. Miller davem@davemloft.net 2023-08-16T10:11:24+00:00 de4c5efeeca7172306bdc2e3efc0c6c3953bb338 Florisn Westphal says: ==================== These are netfilter fixes for the *net* tree. First patch resolves a false-positive lockdep splat: rcu_dereference is used outside of rcu read lock. Let lockdep validate that the transaction mutex is locked. Second patch fixes a kdoc warning added in previous PR. Third patch fixes a memory leak: The catchall element isn't disabled correctly, this allows userspace to deactivate the element again. This results in refcount underflow which in turn prevents memory release. This was always broken since the feature was added in 5.13. Patch 4 fixes an incorrect change in the previous pull request: Adding a duplicate key to a set should work if the duplicate key has expired, restore this behaviour. All from myself. Patch #5 resolves an old historic artifact in sctp conntrack: a 300ms timeout for shutdown_ack. Increase this to 3s. From Xin Long. Patch #6 fixes a sysctl data race in ipvs, two threads can clobber the sysctl value, from Sishuai Gong. This is a day-0 bug that predates git history. Patches 7, 8 and 9, from Pablo Neira Ayuso, are also followups for the previous GC rework in nf_tables: The netlink notifier and the netns exit path must both increment the gc worker seqcount, else worker may encounter stale (free'd) pointers. ================ Signed-off-by: David S. Miller <davem@davemloft.net> 
Florisn Westphal says:

====================
These are netfilter fixes for the *net* tree.

First patch resolves a false-positive lockdep splat:
rcu_dereference is used outside of rcu read lock.  Let lockdep
validate that the transaction mutex is locked.

Second patch fixes a kdoc warning added in previous PR.

Third patch fixes a memory leak:
The catchall element isn't disabled correctly, this allows
userspace to deactivate the element again. This results in refcount
underflow which in turn prevents memory release. This was always
broken since the feature was added in 5.13.

Patch 4 fixes an incorrect change in the previous pull request:
Adding a duplicate key to a set should work if the duplicate key
has expired, restore this behaviour. All from myself.

Patch #5 resolves an old historic artifact in sctp conntrack:
a 300ms timeout for shutdown_ack. Increase this to 3s.  From Xin Long.

Patch #6 fixes a sysctl data race in ipvs, two threads can clobber the
sysctl value, from Sishuai Gong. This is a day-0 bug that predates git
history.

Patches 7, 8 and 9, from Pablo Neira Ayuso, are also followups
for the previous GC rework in nf_tables: The netlink notifier and the
netns exit path must both increment the gc worker seqcount, else worker
may encounter stale (free'd) pointers.
================

Signed-off-by: David S. Miller <davem@davemloft.net>
Merge tag 'ipsec-2023-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec 2023-08-16T07:57:41+00:00 David S. Miller davem@davemloft.net 2023-08-16T07:57:41+00:00 5fc43ce03bc3e50d16a94ec31fba3318ff1cbcd0 Steffen Klassert says: ==================== 1) Fix a slab-out-of-bounds read in xfrm_address_filter. From Lin Ma. 2) Fix the pfkey sadb_x_filter validation. From Lin Ma. 3) Use the correct nla_policy structure for XFRMA_SEC_CTX. From Lin Ma. 4) Fix warnings triggerable by bad packets in the encap functions. From Herbert Xu. 5) Fix some slab-use-after-free in decode_session6. From Zhengchao Shao. 6) Fix a possible NULL piointer dereference in xfrm_update_ae_params. Lin Ma. 7) Add a forgotten nla_policy for XFRMA_MTIMER_THRESH. From Lin Ma. 8) Don't leak offloaded policies. From Leon Romanovsky. 9) Delete also the offloading part of an acquire state. From Leon Romanovsky. Please pull or let me know if there are problems. 
Steffen Klassert says:

====================
1) Fix a slab-out-of-bounds read in xfrm_address_filter.
   From Lin Ma.

2) Fix the pfkey sadb_x_filter validation.
   From Lin Ma.

3) Use the correct nla_policy structure for XFRMA_SEC_CTX.
   From Lin Ma.

4) Fix warnings triggerable by bad packets in the encap functions.
   From Herbert Xu.

5) Fix some slab-use-after-free in decode_session6.
   From Zhengchao Shao.

6) Fix a possible NULL piointer dereference in xfrm_update_ae_params.
   Lin Ma.

7) Add a forgotten nla_policy for XFRMA_MTIMER_THRESH.
   From Lin Ma.

8) Don't leak offloaded policies.
   From Leon Romanovsky.

9) Delete also the offloading part of an acquire state.
   From Leon Romanovsky.

Please pull or let me know if there are problems.
netfilter: nf_tables: fix kdoc warnings after gc rework 2023-08-15T22:05:14+00:00 Florian Westphal fw@strlen.de 2023-08-10T21:59:03+00:00 08713cb006b6f07434f276c5ee214fb20c7fd965 Jakub Kicinski says: We've got some new kdoc warnings here: net/netfilter/nft_set_pipapo.c:1557: warning: Function parameter or member '_set' not described in 'pipapo_gc' net/netfilter/nft_set_pipapo.c:1557: warning: Excess function parameter 'set' description in 'pipapo_gc' include/net/netfilter/nf_tables.h:577: warning: Function parameter or member 'dead' not described in 'nft_set' Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane") Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API") Reported-by: Jakub Kicinski <kuba@kernel.org> Closes: https://lore.kernel.org/netdev/20230810104638.746e46f1@kernel.org/ Signed-off-by: Florian Westphal <fw@strlen.de> 
Jakub Kicinski says:
  We've got some new kdoc warnings here:
  net/netfilter/nft_set_pipapo.c:1557: warning: Function parameter or member '_set' not described in 'pipapo_gc'
  net/netfilter/nft_set_pipapo.c:1557: warning: Excess function parameter 'set' description in 'pipapo_gc'
  include/net/netfilter/nf_tables.h:577: warning: Function parameter or member 'dead' not described in 'nft_set'

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Closes: https://lore.kernel.org/netdev/20230810104638.746e46f1@kernel.org/
Signed-off-by: Florian Westphal <fw@strlen.de>
Merge tag 'nf-23-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf 2023-08-10T17:47:08+00:00 Jakub Kicinski kuba@kernel.org 2023-08-10T17:47:07+00:00 3e91b0ebd994635df2346353322ac51ce84ce6d8 Pablo Neira Ayuso says: ==================== Netfilter fixes for net The existing attempt to resolve races between control plane and GC work is error prone, as reported by Bien Pham <phamnnb@sea.com>, some places forgot to call nft_set_elem_mark_busy(), leading to double-deactivation of elements. This series contains the following patches: 1) Do not skip expired elements during walk otherwise elements might never decrement the reference counter on data, leading to memleak. 2) Add a GC transaction API to replace the former attempt to deal with races between control plane and GC. GC worker sets on NFT_SET_ELEM_DEAD_BIT on elements and it creates a GC transaction to remove the expired elements, GC transaction could abort in case of interference with control plane and retried later (GC async). Set backends such as rbtree and pipapo also perform GC from control plane (GC sync), in such case, element deactivation and removal is safe because mutex is held then collected elements are released via call_rcu(). 3) Adapt existing set backends to use the GC transaction API. 4) Update rhash set backend to set on _DEAD bit to report deleted elements from datapath for GC. 5) Remove old GC batch API and the NFT_SET_ELEM_BUSY_BIT. * tag 'nf-23-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nf_tables: remove busy mark and gc batch API netfilter: nft_set_hash: mark set element as dead when deleting from packet path netfilter: nf_tables: adapt set backend to use GC transaction API netfilter: nf_tables: GC transaction API to avoid race with control plane netfilter: nf_tables: don't skip expired elements during walk ==================== Link: https://lore.kernel.org/r/20230810070830.24064-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The existing attempt to resolve races between control plane and GC work
is error prone, as reported by Bien Pham <phamnnb@sea.com>, some places
forgot to call nft_set_elem_mark_busy(), leading to double-deactivation
of elements.

This series contains the following patches:

1) Do not skip expired elements during walk otherwise elements might
   never decrement the reference counter on data, leading to memleak.

2) Add a GC transaction API to replace the former attempt to deal with
   races between control plane and GC. GC worker sets on NFT_SET_ELEM_DEAD_BIT
   on elements and it creates a GC transaction to remove the expired
   elements, GC transaction could abort in case of interference with
   control plane and retried later (GC async). Set backends such as
   rbtree and pipapo also perform GC from control plane (GC sync), in
   such case, element deactivation and removal is safe because mutex
   is held then collected elements are released via call_rcu().

3) Adapt existing set backends to use the GC transaction API.

4) Update rhash set backend to set on _DEAD bit to report deleted
   elements from datapath for GC.

5) Remove old GC batch API and the NFT_SET_ELEM_BUSY_BIT.

* tag 'nf-23-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nf_tables: remove busy mark and gc batch API
  netfilter: nft_set_hash: mark set element as dead when deleting from packet path
  netfilter: nf_tables: adapt set backend to use GC transaction API
  netfilter: nf_tables: GC transaction API to avoid race with control plane
  netfilter: nf_tables: don't skip expired elements during walk
====================

Link: https://lore.kernel.org/r/20230810070830.24064-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netfilter: nf_tables: remove busy mark and gc batch API 2023-08-10T06:25:27+00:00 Pablo Neira Ayuso pablo@netfilter.org 2023-08-09T13:00:36+00:00 a2dd0233cbc4d8a0abb5f64487487ffc9265beb5 Ditch it, it has been replace it by the GC transaction API and it has no clients anymore. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
Ditch it, it has been replace it by the GC transaction API and it has no
clients anymore.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nf_tables: GC transaction API to avoid race with control plane 2023-08-10T06:25:16+00:00 Pablo Neira Ayuso pablo@netfilter.org 2023-08-09T12:31:54+00:00 5f68718b34a531a556f2f50300ead2862278da26 The set types rhashtable and rbtree use a GC worker to reclaim memory. From system work queue, in periodic intervals, a scan of the table is done. The major caveat here is that the nft transaction mutex is not held. This causes a race between control plane and GC when they attempt to delete the same element. We cannot grab the netlink mutex from the work queue, because the control plane has to wait for the GC work queue in case the set is to be removed, so we get following deadlock: cpu 1 cpu2 GC work transaction comes in , lock nft mutex `acquire nft mutex // BLOCKS transaction asks to remove the set set destruction calls cancel_work_sync() cancel_work_sync will now block forever, because it is waiting for the mutex the caller already owns. This patch adds a new API that deals with garbage collection in two steps: 1) Lockless GC of expired elements sets on the NFT_SET_ELEM_DEAD_BIT so they are not visible via lookup. Annotate current GC sequence in the GC transaction. Enqueue GC transaction work as soon as it is full. If ruleset is updated, then GC transaction is aborted and retried later. 2) GC work grabs the mutex. If GC sequence has changed then this GC transaction lost race with control plane, abort it as it contains stale references to objects and let GC try again later. If the ruleset is intact, then this GC transaction deactivates and removes the elements and it uses call_rcu() to destroy elements. Note that no elements are removed from GC lockless path, the _DEAD bit is set and pointers are collected. GC catchall does not remove the elements anymore too. There is a new set->dead flag that is set on to abort the GC transaction to deal with set->ops->destroy() path which removes the remaining elements in the set from commit_release, where no mutex is held. To deal with GC when mutex is held, which allows safe deactivate and removal, add sync GC API which releases the set element object via call_rcu(). This is used by rbtree and pipapo backends which also perform garbage collection from control plane path. Since element removal from sets can happen from control plane and element garbage collection/timeout, it is necessary to keep the set structure alive until all elements have been deactivated and destroyed. We cannot do a cancel_work_sync or flush_work in nft_set_destroy because its called with the transaction mutex held, but the aforementioned async work queue might be blocked on the very mutex that nft_set_destroy() callchain is sitting on. This gives us the choice of ABBA deadlock or UaF. To avoid both, add set->refs refcount_t member. The GC API can then increment the set refcount and release it once the elements have been free'd. Set backends are adapted to use the GC transaction API in a follow up patch entitled: ("netfilter: nf_tables: use gc transaction API in set backends") This is joint work with Florian Westphal. Fixes: cfed7e1b1f8e ("netfilter: nf_tables: add set garbage collection helpers") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
The set types rhashtable and rbtree use a GC worker to reclaim memory.
From system work queue, in periodic intervals, a scan of the table is
done.

The major caveat here is that the nft transaction mutex is not held.
This causes a race between control plane and GC when they attempt to
delete the same element.

We cannot grab the netlink mutex from the work queue, because the
control plane has to wait for the GC work queue in case the set is to be
removed, so we get following deadlock:

   cpu 1                                cpu2
     GC work                            transaction comes in , lock nft mutex
       `acquire nft mutex // BLOCKS
                                        transaction asks to remove the set
                                        set destruction calls cancel_work_sync()

cancel_work_sync will now block forever, because it is waiting for the
mutex the caller already owns.

This patch adds a new API that deals with garbage collection in two
steps:

1) Lockless GC of expired elements sets on the NFT_SET_ELEM_DEAD_BIT
   so they are not visible via lookup. Annotate current GC sequence in
   the GC transaction. Enqueue GC transaction work as soon as it is
   full. If ruleset is updated, then GC transaction is aborted and
   retried later.

2) GC work grabs the mutex. If GC sequence has changed then this GC
   transaction lost race with control plane, abort it as it contains
   stale references to objects and let GC try again later. If the
   ruleset is intact, then this GC transaction deactivates and removes
   the elements and it uses call_rcu() to destroy elements.

Note that no elements are removed from GC lockless path, the _DEAD bit
is set and pointers are collected. GC catchall does not remove the
elements anymore too. There is a new set->dead flag that is set on to
abort the GC transaction to deal with set->ops->destroy() path which
removes the remaining elements in the set from commit_release, where no
mutex is held.

To deal with GC when mutex is held, which allows safe deactivate and
removal, add sync GC API which releases the set element object via
call_rcu(). This is used by rbtree and pipapo backends which also
perform garbage collection from control plane path.

Since element removal from sets can happen from control plane and
element garbage collection/timeout, it is necessary to keep the set
structure alive until all elements have been deactivated and destroyed.

We cannot do a cancel_work_sync or flush_work in nft_set_destroy because
its called with the transaction mutex held, but the aforementioned async
work queue might be blocked on the very mutex that nft_set_destroy()
callchain is sitting on.

This gives us the choice of ABBA deadlock or UaF.

To avoid both, add set->refs refcount_t member. The GC API can then
increment the set refcount and release it once the elements have been
free'd.

Set backends are adapted to use the GC transaction API in a follow up
patch entitled:

  ("netfilter: nf_tables: use gc transaction API in set backends")

This is joint work with Florian Westphal.

Fixes: cfed7e1b1f8e ("netfilter: nf_tables: add set garbage collection helpers")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Merge tag 'wireless-2023-08-09' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless 2023-08-09T22:04:44+00:00 Jakub Kicinski kuba@kernel.org 2023-08-09T22:04:44+00:00 15c8795dbff8105b9071a7e38e6d4a1649747ec9 Johannes Berg says: ==================== Just a few small updates: * fix an integer overflow in nl80211 * fix rtw89 8852AE disconnections * fix a buffer overflow in ath12k * fix AP_VLAN configuration lookups * fix allocation failure handling in brcm80211 * update MAINTAINERS for some drivers * tag 'wireless-2023-08-09' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless: wifi: ath12k: Fix buffer overflow when scanning with extraie wifi: nl80211: fix integer overflow in nl80211_parse_mbssid_elems() wifi: cfg80211: fix sband iftype data lookup for AP_VLAN wifi: rtw89: fix 8852AE disconnection caused by RX full flags MAINTAINERS: Remove tree entry for rtl8180 MAINTAINERS: Update entry for rtl8187 wifi: brcm80211: handle params_v1 allocation failure ==================== Link: https://lore.kernel.org/r/20230809124818.167432-2-johannes@sipsolutions.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Johannes Berg says:

====================
Just a few small updates:
 * fix an integer overflow in nl80211
 * fix rtw89 8852AE disconnections
 * fix a buffer overflow in ath12k
 * fix AP_VLAN configuration lookups
 * fix allocation failure handling in brcm80211
 * update MAINTAINERS for some drivers

* tag 'wireless-2023-08-09' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless:
  wifi: ath12k: Fix buffer overflow when scanning with extraie
  wifi: nl80211: fix integer overflow in nl80211_parse_mbssid_elems()
  wifi: cfg80211: fix sband iftype data lookup for AP_VLAN
  wifi: rtw89: fix 8852AE disconnection caused by RX full flags
  MAINTAINERS: Remove tree entry for rtl8180
  MAINTAINERS: Update entry for rtl8187
  wifi: brcm80211: handle params_v1 allocation failure
====================

Link: https://lore.kernel.org/r/20230809124818.167432-2-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
wifi: cfg80211: fix sband iftype data lookup for AP_VLAN 2023-08-08T11:01:19+00:00 Felix Fietkau nbd@nbd.name 2023-06-22T16:59:19+00:00 5fb9a9fb71a33be61d7d8e8ba4597bfb18d604d0 AP_VLAN interfaces are virtual, so doesn't really exist as a type for capabilities. When passed in as a type, AP is the one that's really intended. Fixes: c4cbaf7973a7 ("cfg80211: Add support for HE") Signed-off-by: Felix Fietkau <nbd@nbd.name> Link: https://lore.kernel.org/r/20230622165919.46841-1-nbd@nbd.name Signed-off-by: Johannes Berg <johannes.berg@intel.com> 
AP_VLAN interfaces are virtual, so doesn't really exist as a type for
capabilities. When passed in as a type, AP is the one that's really intended.

Fixes: c4cbaf7973a7 ("cfg80211: Add support for HE")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20230622165919.46841-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
vxlan: Fix nexthop hash size 2023-08-02T09:58:26+00:00 Benjamin Poirier bpoirier@nvidia.com 2023-07-31T20:02:08+00:00 0756384fb1bd38adb2ebcfd1307422f433a1d772 The nexthop code expects a 31 bit hash, such as what is returned by fib_multipath_hash() and rt6_multipath_hash(). Passing the 32 bit hash returned by skb_get_hash() can lead to problems related to the fact that 'int hash' is a negative number when the MSB is set. In the case of hash threshold nexthop groups, nexthop_select_path_hthr() will disproportionately select the first nexthop group entry. In the case of resilient nexthop groups, nexthop_select_path_res() may do an out of bounds access in nh_buckets[], for example: hash = -912054133 num_nh_buckets = 2 bucket_index = 65535 which leads to the following panic: BUG: unable to handle page fault for address: ffffc900025910c8 PGD 100000067 P4D 100000067 PUD 10026b067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI CPU: 4 PID: 856 Comm: kworker/4:3 Not tainted 6.5.0-rc2+ #34 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:nexthop_select_path+0x197/0xbf0 Code: c1 e4 05 be 08 00 00 00 4c 8b 35 a4 14 7e 01 4e 8d 6c 25 00 4a 8d 7c 25 08 48 01 dd e8 c2 25 15 ff 49 8d 7d 08 e8 39 13 15 ff <4d> 89 75 08 48 89 ef e8 7d 12 15 ff 48 8b 5d 00 e8 14 55 2f 00 85 RSP: 0018:ffff88810c36f260 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000002000c0 RCX: ffffffffaf02dd77 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffc900025910c8 RBP: ffffc900025910c0 R08: 0000000000000001 R09: fffff520004b2219 R10: ffffc900025910cf R11: 31392d2068736168 R12: 00000000002000c0 R13: ffffc900025910c0 R14: 00000000fffef608 R15: ffff88811840e900 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc900025910c8 CR3: 0000000129d00000 CR4: 0000000000750ee0 PKRU: 55555554 Call Trace: <TASK> ? __die+0x23/0x70 ? page_fault_oops+0x1ee/0x5c0 ? __pfx_is_prefetch.constprop.0+0x10/0x10 ? __pfx_page_fault_oops+0x10/0x10 ? search_bpf_extables+0xfe/0x1c0 ? fixup_exception+0x3b/0x470 ? exc_page_fault+0xf6/0x110 ? asm_exc_page_fault+0x26/0x30 ? nexthop_select_path+0x197/0xbf0 ? nexthop_select_path+0x197/0xbf0 ? lock_is_held_type+0xe7/0x140 vxlan_xmit+0x5b2/0x2340 ? __lock_acquire+0x92b/0x3370 ? __pfx_vxlan_xmit+0x10/0x10 ? __pfx___lock_acquire+0x10/0x10 ? __pfx_register_lock_class+0x10/0x10 ? skb_network_protocol+0xce/0x2d0 ? dev_hard_start_xmit+0xca/0x350 ? __pfx_vxlan_xmit+0x10/0x10 dev_hard_start_xmit+0xca/0x350 __dev_queue_xmit+0x513/0x1e20 ? __pfx___dev_queue_xmit+0x10/0x10 ? __pfx_lock_release+0x10/0x10 ? mark_held_locks+0x44/0x90 ? skb_push+0x4c/0x80 ? eth_header+0x81/0xe0 ? __pfx_eth_header+0x10/0x10 ? neigh_resolve_output+0x215/0x310 ? ip6_finish_output2+0x2ba/0xc90 ip6_finish_output2+0x2ba/0xc90 ? lock_release+0x236/0x3e0 ? ip6_mtu+0xbb/0x240 ? __pfx_ip6_finish_output2+0x10/0x10 ? find_held_lock+0x83/0xa0 ? lock_is_held_type+0xe7/0x140 ip6_finish_output+0x1ee/0x780 ip6_output+0x138/0x460 ? __pfx_ip6_output+0x10/0x10 ? __pfx___lock_acquire+0x10/0x10 ? __pfx_ip6_finish_output+0x10/0x10 NF_HOOK.constprop.0+0xc0/0x420 ? __pfx_NF_HOOK.constprop.0+0x10/0x10 ? ndisc_send_skb+0x2c0/0x960 ? __pfx_lock_release+0x10/0x10 ? __local_bh_enable_ip+0x93/0x110 ? lock_is_held_type+0xe7/0x140 ndisc_send_skb+0x4be/0x960 ? __pfx_ndisc_send_skb+0x10/0x10 ? mark_held_locks+0x65/0x90 ? find_held_lock+0x83/0xa0 ndisc_send_ns+0xb0/0x110 ? __pfx_ndisc_send_ns+0x10/0x10 addrconf_dad_work+0x631/0x8e0 ? lock_acquire+0x180/0x3f0 ? __pfx_addrconf_dad_work+0x10/0x10 ? mark_held_locks+0x24/0x90 process_one_work+0x582/0x9c0 ? __pfx_process_one_work+0x10/0x10 ? __pfx_do_raw_spin_lock+0x10/0x10 ? mark_held_locks+0x24/0x90 worker_thread+0x93/0x630 ? __kthread_parkme+0xdc/0x100 ? __pfx_worker_thread+0x10/0x10 kthread+0x1a5/0x1e0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x34/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 RIP: 0000:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: CR2: ffffc900025910c8 ---[ end trace 0000000000000000 ]--- RIP: 0010:nexthop_select_path+0x197/0xbf0 Code: c1 e4 05 be 08 00 00 00 4c 8b 35 a4 14 7e 01 4e 8d 6c 25 00 4a 8d 7c 25 08 48 01 dd e8 c2 25 15 ff 49 8d 7d 08 e8 39 13 15 ff <4d> 89 75 08 48 89 ef e8 7d 12 15 ff 48 8b 5d 00 e8 14 55 2f 00 85 RSP: 0018:ffff88810c36f260 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00000000002000c0 RCX: ffffffffaf02dd77 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffc900025910c8 RBP: ffffc900025910c0 R08: 0000000000000001 R09: fffff520004b2219 R10: ffffc900025910cf R11: 31392d2068736168 R12: 00000000002000c0 R13: ffffc900025910c0 R14: 00000000fffef608 R15: ffff88811840e900 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000129d00000 CR4: 0000000000750ee0 PKRU: 55555554 Kernel panic - not syncing: Fatal exception in interrupt Kernel Offset: 0x2ca00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]--- Fix this problem by ensuring the MSB of hash is 0 using a right shift - the same approach used in fib_multipath_hash() and rt6_multipath_hash(). Fixes: 1274e1cc4226 ("vxlan: ecmp support for mac fdb entries") Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
The nexthop code expects a 31 bit hash, such as what is returned by
fib_multipath_hash() and rt6_multipath_hash(). Passing the 32 bit hash
returned by skb_get_hash() can lead to problems related to the fact that
'int hash' is a negative number when the MSB is set.

In the case of hash threshold nexthop groups, nexthop_select_path_hthr()
will disproportionately select the first nexthop group entry. In the case
of resilient nexthop groups, nexthop_select_path_res() may do an out of
bounds access in nh_buckets[], for example:
    hash = -912054133
    num_nh_buckets = 2
    bucket_index = 65535

which leads to the following panic:

BUG: unable to handle page fault for address: ffffc900025910c8
PGD 100000067 P4D 100000067 PUD 10026b067 PMD 0
Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI
CPU: 4 PID: 856 Comm: kworker/4:3 Not tainted 6.5.0-rc2+ #34
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:nexthop_select_path+0x197/0xbf0
Code: c1 e4 05 be 08 00 00 00 4c 8b 35 a4 14 7e 01 4e 8d 6c 25 00 4a 8d 7c 25 08 48 01 dd e8 c2 25 15 ff 49 8d 7d 08 e8 39 13 15 ff <4d> 89 75 08 48 89 ef e8 7d 12 15 ff 48 8b 5d 00 e8 14 55 2f 00 85
RSP: 0018:ffff88810c36f260 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000002000c0 RCX: ffffffffaf02dd77
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffc900025910c8
RBP: ffffc900025910c0 R08: 0000000000000001 R09: fffff520004b2219
R10: ffffc900025910cf R11: 31392d2068736168 R12: 00000000002000c0
R13: ffffc900025910c0 R14: 00000000fffef608 R15: ffff88811840e900
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc900025910c8 CR3: 0000000129d00000 CR4: 0000000000750ee0
PKRU: 55555554
Call Trace:
 <TASK>
 ? __die+0x23/0x70
 ? page_fault_oops+0x1ee/0x5c0
 ? __pfx_is_prefetch.constprop.0+0x10/0x10
 ? __pfx_page_fault_oops+0x10/0x10
 ? search_bpf_extables+0xfe/0x1c0
 ? fixup_exception+0x3b/0x470
 ? exc_page_fault+0xf6/0x110
 ? asm_exc_page_fault+0x26/0x30
 ? nexthop_select_path+0x197/0xbf0
 ? nexthop_select_path+0x197/0xbf0
 ? lock_is_held_type+0xe7/0x140
 vxlan_xmit+0x5b2/0x2340
 ? __lock_acquire+0x92b/0x3370
 ? __pfx_vxlan_xmit+0x10/0x10
 ? __pfx___lock_acquire+0x10/0x10
 ? __pfx_register_lock_class+0x10/0x10
 ? skb_network_protocol+0xce/0x2d0
 ? dev_hard_start_xmit+0xca/0x350
 ? __pfx_vxlan_xmit+0x10/0x10
 dev_hard_start_xmit+0xca/0x350
 __dev_queue_xmit+0x513/0x1e20
 ? __pfx___dev_queue_xmit+0x10/0x10
 ? __pfx_lock_release+0x10/0x10
 ? mark_held_locks+0x44/0x90
 ? skb_push+0x4c/0x80
 ? eth_header+0x81/0xe0
 ? __pfx_eth_header+0x10/0x10
 ? neigh_resolve_output+0x215/0x310
 ? ip6_finish_output2+0x2ba/0xc90
 ip6_finish_output2+0x2ba/0xc90
 ? lock_release+0x236/0x3e0
 ? ip6_mtu+0xbb/0x240
 ? __pfx_ip6_finish_output2+0x10/0x10
 ? find_held_lock+0x83/0xa0
 ? lock_is_held_type+0xe7/0x140
 ip6_finish_output+0x1ee/0x780
 ip6_output+0x138/0x460
 ? __pfx_ip6_output+0x10/0x10
 ? __pfx___lock_acquire+0x10/0x10
 ? __pfx_ip6_finish_output+0x10/0x10
 NF_HOOK.constprop.0+0xc0/0x420
 ? __pfx_NF_HOOK.constprop.0+0x10/0x10
 ? ndisc_send_skb+0x2c0/0x960
 ? __pfx_lock_release+0x10/0x10
 ? __local_bh_enable_ip+0x93/0x110
 ? lock_is_held_type+0xe7/0x140
 ndisc_send_skb+0x4be/0x960
 ? __pfx_ndisc_send_skb+0x10/0x10
 ? mark_held_locks+0x65/0x90
 ? find_held_lock+0x83/0xa0
 ndisc_send_ns+0xb0/0x110
 ? __pfx_ndisc_send_ns+0x10/0x10
 addrconf_dad_work+0x631/0x8e0
 ? lock_acquire+0x180/0x3f0
 ? __pfx_addrconf_dad_work+0x10/0x10
 ? mark_held_locks+0x24/0x90
 process_one_work+0x582/0x9c0
 ? __pfx_process_one_work+0x10/0x10
 ? __pfx_do_raw_spin_lock+0x10/0x10
 ? mark_held_locks+0x24/0x90
 worker_thread+0x93/0x630
 ? __kthread_parkme+0xdc/0x100
 ? __pfx_worker_thread+0x10/0x10
 kthread+0x1a5/0x1e0
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x34/0x60
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1b/0x30
RIP: 0000:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
CR2: ffffc900025910c8
---[ end trace 0000000000000000 ]---
RIP: 0010:nexthop_select_path+0x197/0xbf0
Code: c1 e4 05 be 08 00 00 00 4c 8b 35 a4 14 7e 01 4e 8d 6c 25 00 4a 8d 7c 25 08 48 01 dd e8 c2 25 15 ff 49 8d 7d 08 e8 39 13 15 ff <4d> 89 75 08 48 89 ef e8 7d 12 15 ff 48 8b 5d 00 e8 14 55 2f 00 85
RSP: 0018:ffff88810c36f260 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000002000c0 RCX: ffffffffaf02dd77
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffc900025910c8
RBP: ffffc900025910c0 R08: 0000000000000001 R09: fffff520004b2219
R10: ffffc900025910cf R11: 31392d2068736168 R12: 00000000002000c0
R13: ffffc900025910c0 R14: 00000000fffef608 R15: ffff88811840e900
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000129d00000 CR4: 0000000000750ee0
PKRU: 55555554
Kernel panic - not syncing: Fatal exception in interrupt
Kernel Offset: 0x2ca00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Fix this problem by ensuring the MSB of hash is 0 using a right shift - the
same approach used in fib_multipath_hash() and rt6_multipath_hash().

Fixes: 1274e1cc4226 ("vxlan: ecmp support for mac fdb entries")
Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>