Daniel Borkmann says:

====================
pull-request: bpf 2023-09-06

We've added 9 non-merge commits during the last 6 day(s) which contain
a total of 12 files changed, 189 insertions(+), 44 deletions(-).

The main changes are:

1) Fix bpf_sk_storage to address an invalid wait context lockdep
   report and another one to address missing omem uncharge,
   from Martin KaFai Lau.

2) Two BPF recursion detection related fixes,
   from Sebastian Andrzej Siewior.

3) Fix tailcall limit enforcement in trampolines for s390 JIT,
   from Ilya Leoshkevich.

4) Fix a sockmap refcount race where skbs in sk_psock_backlog can
   be referenced after user space side has already skb_consumed them,
   from John Fastabend.

5) Fix BPF CI flake/race wrt sockmap vsock write test where
   the transport endpoint is not connected, from Xu Kuohai.

6) Follow-up doc fix to address a cross-link warning,
   from Eduard Zingerman.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Check bpf_sk_storage has uncharged sk_omem_alloc
  bpf: bpf_sk_storage: Fix the missing uncharge in sk_omem_alloc
  bpf: bpf_sk_storage: Fix invalid wait context lockdep report
  s390/bpf: Pass through tail call counter in trampolines
  bpf: Assign bpf_tramp_run_ctx::saved_run_ctx before recursion check.
  bpf: Invoke __bpf_prog_exit_sleepable_recur() on recursion in kern_sys_bpf().
  bpf, sockmap: Fix skb refcnt race after locking changes
  docs/bpf: Fix "file doesn't exist" warnings in {llvm_reloc,btf}.rst
  selftests/bpf: Fix a CI failure caused by vsock write
====================

Link: https://lore.kernel.org/r/20230906095117.16941-1-daniel@iogearbox.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

This patch checks the sk_omem_alloc has been uncharged by bpf_sk_storage
during the __sk_destruct.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230901231129.578493-4-martin.lau@linux.dev

The commit c83597fa ("bpf: Refactor some inode/task/sk storage functions
for reuse"), refactored the bpf_{sk,task,inode}_storage_free() into
bpf_local_storage_unlink_nolock() which then later renamed to
bpf_local_storage_destroy(). The commit accidentally passed the
"bool uncharge_mem = false" argument to bpf_selem_unlink_storage_nolock()
which then stopped the uncharge from happening to the sk->sk_omem_alloc.

This missing uncharge only happens when the sk is going away (during
__sk_destruct).

This patch fixes it by always passing "uncharge_mem = true". It is a
noop to the task/inode/cgroup storage because they do not have the
map_local_storage_(un)charge enabled in the map_ops. A followup patch
will be done in bpf-next to remove the uncharge_mem argument.

A selftest is added in the next patch.

Fixes: c83597fa ("bpf: Refactor some inode/task/sk storage functions for reuse")
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230901231129.578493-3-martin.lau@linux.dev

'./test_progs -t test_local_storage' reported a splat:

[   27.137569] =============================
[   27.138122] [ BUG: Invalid wait context ]
[   27.138650] 6.5.0-03980-gd11ae1b1 #247 Tainted: G           O
[   27.139542] -----------------------------
[   27.140106] test_progs/1729 is trying to lock:
[   27.140713] ffff8883ef047b88 (stock_lock){-.-.}-{3:3}, at: local_lock_acquire+0x9/0x130
[   27.141834] other info that might help us debug this:
[   27.142437] context-{5:5}
[   27.142856] 2 locks held by test_progs/1729:
[   27.143352]  #0: ffffffff84bcd9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x40
[   27.144492]  #1: ffff888107deb2c0 (&storage->lock){..-.}-{2:2}, at: bpf_local_storage_update+0x39e/0x8e0
[   27.145855] stack backtrace:
[   27.146274] CPU: 0 PID: 1729 Comm: test_progs Tainted: G           O       6.5.0-03980-gd11ae1b1 #247
[   27.147550] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[   27.149127] Call Trace:
[   27.149490]  <TASK>
[   27.149867]  dump_stack_lvl+0x130/0x1d0
[   27.152609]  dump_stack+0x14/0x20
[   27.153131]  __lock_acquire+0x1657/0x2220
[   27.153677]  lock_acquire+0x1b8/0x510
[   27.157908]  local_lock_acquire+0x29/0x130
[   27.159048]  obj_cgroup_charge+0xf4/0x3c0
[   27.160794]  slab_pre_alloc_hook+0x28e/0x2b0
[   27.161931]  __kmem_cache_alloc_node+0x51/0x210
[   27.163557]  __kmalloc+0xaa/0x210
[   27.164593]  bpf_map_kzalloc+0xbc/0x170
[   27.165147]  bpf_selem_alloc+0x130/0x510
[   27.166295]  bpf_local_storage_update+0x5aa/0x8e0
[   27.167042]  bpf_fd_sk_storage_update_elem+0xdb/0x1a0
[   27.169199]  bpf_map_update_value+0x415/0x4f0
[   27.169871]  map_update_elem+0x413/0x550
[   27.170330]  __sys_bpf+0x5e9/0x640
[   27.174065]  __x64_sys_bpf+0x80/0x90
[   27.174568]  do_syscall_64+0x48/0xa0
[   27.175201]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[   27.175932] RIP: 0033:0x7effb40e41ad
[   27.176357] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 8b 0d8
[   27.179028] RSP: 002b:00007ffe64c21fc8 EFLAGS: 00000202 ORIG_RAX: 0000000000000141
[   27.180088] RAX: ffffffffffffffda RBX: 00007ffe64c22768 RCX: 00007effb40e41ad
[   27.181082] RDX: 0000000000000020 RSI: 00007ffe64c22008 RDI: 0000000000000002
[   27.182030] RBP: 00007ffe64c21ff0 R08: 0000000000000000 R09: 00007ffe64c22788
[   27.183038] R10: 0000000000000064 R11: 0000000000000202 R12: 0000000000000000
[   27.184006] R13: 00007ffe64c22788 R14: 00007effb42a1000 R15: 0000000000000000
[   27.184958]  </TASK>

It complains about acquiring a local_lock while holding a raw_spin_lock.
It means it should not allocate memory while holding a raw_spin_lock
since it is not safe for RT.

raw_spin_lock is needed because bpf_local_storage supports tracing
context. In particular for task local storage, it is easy to
get a "current" task PTR_TO_BTF_ID in tracing bpf prog.
However, task (and cgroup) local storage has already been moved to
bpf mem allocator which can be used after raw_spin_lock.

The splat is for the sk storage. For sk (and inode) storage,
it has not been moved to bpf mem allocator. Using raw_spin_lock or not,
kzalloc(GFP_ATOMIC) could theoretically be unsafe in tracing context.
However, the local storage helper requires a verifier accepted
sk pointer (PTR_TO_BTF_ID), it is hypothetical if that (mean running
a bpf prog in a kzalloc unsafe context and also able to hold a verifier
accepted sk pointer) could happen.

This patch avoids kzalloc after raw_spin_lock to silent the splat.
There is an existing kzalloc before the raw_spin_lock. At that point,
a kzalloc is very likely required because a lookup has just been done
before. Thus, this patch always does the kzalloc before acquiring
the raw_spin_lock and remove the later kzalloc usage after the
raw_spin_lock. After this change, it will have a charge and then
uncharge during the syscall bpf_map_update_elem() code path.
This patch opts for simplicity and not continue the old
optimization to save one charge and uncharge.

This issue is dated back to the very first commit of bpf_sk_storage
which had been refactored multiple times to create task, inode, and
cgroup storage. This patch uses a Fixes tag with a more recent
commit that should be easier to do backport.

Fixes: b00fa38a ("bpf: Enable non-atomic allocations in local storage")
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230901231129.578493-2-martin.lau@linux.dev

s390x eBPF programs use the following extension to the s390x calling
convention: tail call counter is passed on stack at offset
STK_OFF_TCCNT, which callees otherwise use as scratch space.

Currently trampoline does not respect this and clobbers tail call
counter. This breaks enforcing tail call limits in eBPF programs, which
have trampolines attached to them.

Fix by forwarding a copy of the tail call counter to the original eBPF
program in the trampoline (for fexit), and by restoring it at the end
of the trampoline (for fentry).

Fixes: 528eb2cb ("s390/bpf: Implement arch_prepare_bpf_trampoline()")
Reported-by: Leon Hwang <hffilwlqm@gmail.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230906004448.111674-1-iii@linux.ibm.com

__bpf_prog_enter_recur() assigns bpf_tramp_run_ctx::saved_run_ctx before
performing the recursion check which means in case of a recursion
__bpf_prog_exit_recur() uses the previously set bpf_tramp_run_ctx::saved_run_ctx
value.

__bpf_prog_enter_sleepable_recur() assigns bpf_tramp_run_ctx::saved_run_ctx
after the recursion check which means in case of a recursion
__bpf_prog_exit_sleepable_recur() uses an uninitialized value. This does not
look right. If I read the entry trampoline code right, then bpf_tramp_run_ctx
isn't initialized upfront.

Align __bpf_prog_enter_sleepable_recur() with __bpf_prog_enter_recur() and
set bpf_tramp_run_ctx::saved_run_ctx before the recursion check is made.
Remove the assignment of saved_run_ctx in kern_sys_bpf() since it happens
a few cycles later.

Fixes: e384c7b7 ("bpf, x86: Create bpf_tramp_run_ctx on the caller thread's stack")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230830080405.251926-3-bigeasy@linutronix.de

If __bpf_prog_enter_sleepable_recur() detects recursion then it returns
0 without undoing rcu_read_lock_trace(), migrate_disable() or
decrementing the recursion counter. This is fine in the JIT case because
the JIT code will jump in the 0 case to the end and invoke the matching
exit trampoline (__bpf_prog_exit_sleepable_recur()).

This is not the case in kern_sys_bpf() which returns directly to the
caller with an error code.

Add __bpf_prog_exit_sleepable_recur() as clean up in the recursion case.

Fixes: b1d18a75 ("bpf: Extend sys_bpf commands for bpf_syscall programs.")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230830080405.251926-2-bigeasy@linutronix.de

sphinx complains about the use of "%PHYLINK_PCS_NEG_*":

Documentation/networking/kapi:144: ./include/linux/phylink.h:601: WARNING: Inline literal start-string without end-string.
Documentation/networking/kapi:144: ./include/linux/phylink.h:633: WARNING: Inline literal start-string without end-string.

These are not valid symbols so drop the '%' prefix.

Alternatively we could use %PHYLINK_PCS_NEG_\* (escape the *)
or use normal literal ``PHYLINK_PCS_NEG_*`` but there is already
a handful of un-adorned DEFINE_* in this file.

Fixes: f99d471a ("net: phylink: add PCS negotiation mode")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/all/20230626162908.2f149f98@canb.auug.org.au/Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Vladimir Oltean says:

====================
tc-cbs offload fixes for SJA1105 DSA

Yanan Yang has pointed out to me that certain tc-cbs offloaded
configurations do not appear to do any shaping on the LS1021A-TSN board
(SJA1105T).

This is due to an apparent documentation error that also made its way
into the driver, which patch 1/3 now fixes.

While investigating and then testing, I've found 2 more bugs, which are
patches 2/3 and 3/3.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The blamed commit left this delta behind:

  struct sja1105_cbs_entry {
 -	u64 port;
 -	u64 prio;
 +	u64 port; /* Not used for SJA1110 */
 +	u64 prio; /* Not used for SJA1110 */
  	u64 credit_hi;
  	u64 credit_lo;
  	u64 send_slope;
  	u64 idle_slope;
  };

but did not actually implement tc-cbs offload fully for the new switch.
The offload is accepted, but it doesn't work.

The difference compared to earlier switch generations is that now, the
table of CBS shapers is sparse, because there are many more shapers, so
the mapping between a {port, prio} and a table index is static, rather
than requiring us to store the port and prio into the sja1105_cbs_entry.

So, the problem is that the code programs the CBS shaper parameters at a
dynamic table index which is incorrect.

All that needs to be done for SJA1110 CBS shapers to work is to bypass
the logic which allocates shapers in a dense manner, as for SJA1105, and
use the fixed mapping instead.

Fixes: 3e77e59b ("net: dsa: sja1105: add support for the SJA1110 switch family")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After running command [2] too many times in a row:

[1] $ tc qdisc add dev sw2p0 root handle 1: mqprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0
[2] $ tc qdisc replace dev sw2p0 parent 1:1 cbs offload 1 \
	idleslope 120000 sendslope -880000 locredit -1320 hicredit 180

(aka more than priv->info->num_cbs_shapers times)

we start seeing the following error message:

Error: Specified device failed to setup cbs hardware offload.

This comes from the fact that ndo_setup_tc(TC_SETUP_QDISC_CBS) presents
the same API for the qdisc create and replace cases, and the sja1105
driver fails to distinguish between the 2. Thus, it always thinks that
it must allocate the same shaper for a {port, queue} pair, when it may
instead have to replace an existing one.

Fixes: 4d752508 ("net: dsa: sja1105: offload the Credit-Based Shaper qdisc")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

More careful measurement of the tc-cbs bandwidth shows that the stream
bandwidth (effectively idleslope) increases, there is a larger and
larger discrepancy between the rate limit obtained by the software
Qdisc, and the rate limit obtained by its offloaded counterpart.

The discrepancy becomes so large, that e.g. at an idleslope of 40000
(40Mbps), the offloaded cbs does not actually rate limit anything, and
traffic will pass at line rate through a 100 Mbps port.

The reason for the discrepancy is that the hardware documentation I've
been following is incorrect. UM11040.pdf (for SJA1105P/Q/R/S) states
about IDLE_SLOPE that it is "the rate (in unit of bytes/sec) at which
the credit counter is increased".

Cross-checking with UM10944.pdf (for SJA1105E/T) and UM11107.pdf
(for SJA1110), the wording is different: "This field specifies the
value, in bytes per second times link speed, by which the credit counter
is increased".

So there's an extra scaling for link speed that the driver is currently
not accounting for, and apparently (empirically), that link speed is
expressed in Kbps.

I've pondered whether to pollute the sja1105_mac_link_up()
implementation with CBS shaper reprogramming, but I don't think it is
worth it. IMO, the UAPI exposed by tc-cbs requires user space to
recalculate the sendslope anyway, since the formula for that depends on
port_transmit_rate (see man tc-cbs), which is not an invariant from tc's
perspective.

So we use the offload->sendslope and offload->idleslope to deduce the
original port_transmit_rate from the CBS formula, and use that value to
scale the offload->sendslope and offload->idleslope to values that the
hardware understands.

Some numerical data points:

 40Mbps stream, max interfering frame size 1500, port speed 100M
 ---------------------------------------------------------------

 tc-cbs parameters:
 idleslope 40000 sendslope -60000 locredit -900 hicredit 600

 which result in hardware values:

 Before (doesn't work)           After (works)
 credit_hi    600                600
 credit_lo    900                900
 send_slope   7500000            75
 idle_slope   5000000            50

 40Mbps stream, max interfering frame size 1500, port speed 1G
 -------------------------------------------------------------

 tc-cbs parameters:
 idleslope 40000 sendslope -960000 locredit -1440 hicredit 60

 which result in hardware values:

 Before (doesn't work)           After (works)
 credit_hi    60                 60
 credit_lo    1440               1440
 send_slope   120000000          120
 idle_slope   5000000            5

 5.12Mbps stream, max interfering frame size 1522, port speed 100M
 -----------------------------------------------------------------

 tc-cbs parameters:
 idleslope 5120 sendslope -94880 locredit -1444 hicredit 77

 which result in hardware values:

 Before (doesn't work)           After (works)
 credit_hi    77                 77
 credit_lo    1444               1444
 send_slope   11860000           118
 idle_slope   640000             6

Tested on SJA1105T, SJA1105S and SJA1110A, at 1Gbps and 100Mbps.

Fixes: 4d752508 ("net: dsa: sja1105: offload the Credit-Based Shaper qdisc")
Reported-by: Yanan Yang <yanan.yang@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Tony Nguyen says:

====================
Change MIN_TXD and MIN_RXD to allow set rx/tx value between 64 and 80

Olga Zaborska says:

Change the minimum value of RX/TX descriptors to 64 to enable setting the rx/tx
value between 64 and 80. All igb, igbvf and igc devices can use as low as 64
descriptors.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

ACL flow table is required in switchdev mode when metadata is enabled,
driver creates such table when loading each vport. However, not every
vport is loaded in switchdev mode. Such as ECPF if it's the eswitch manager.
In this case, ACL flow table is still needed.

To make it modularized, create ACL flow table for eswitch manager as
default and skip such operations when loading manager vport.

Also, there is no need to load the eswitch manager vport in switchdev mode.
This means there is no need to load it on regular connect-x HCAs where
the PF is the eswitch manager. This will avoid creating duplicate ACL
flow table for host PF vport.

Fixes: 29bcb6e4 ("net/mlx5e: E-Switch, Use metadata for vport matching in send-to-vport rules")
Fixes: eb8e9fae ("mlx5/core: E-Switch, Allocate ECPF vport if it's an eswitch manager")
Fixes: 5019833d ("net/mlx5: E-switch, Introduce helper function to enable/disable vports")
Signed-off-by: Bodong Wang <bodong@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In the cited commit, the mirred devices are recorded and checked while
parsing the actions. In order to avoid system crash, the duplicate
action in a single rule is not allowed.

But the rule is actually break down into several FTEs in different
tables, for either mirroring, or the specified types of actions which
use post action infrastructure.

It will reject certain action list by mistake, for example:
    actions:enp8s0f0_1,set(ipv4(ttl=63)),enp8s0f0_0,enp8s0f0_1.
Here the rule is split to two FTEs because of pedit action.

To fix this issue, when parsing the rule actions, reset if_count to
clear the mirred devices array if the rule is split to multiple
FTEs, and then the duplicate checking is restarted.

Fixes: 554fe75c ("net/mlx5e: Avoid duplicating rule destinations")
Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

syzbot/KCSAN reported data-races in iptunnel_xmit_stats() [1]

This can run from multiple cpus without mutual exclusion.

Adopt SMP safe DEV_STATS_INC() to update dev->stats fields.

[1]
BUG: KCSAN: data-race in iptunnel_xmit / iptunnel_xmit

read-write to 0xffff8881353df170 of 8 bytes by task 30263 on cpu 1:
iptunnel_xmit_stats include/net/ip_tunnels.h:493 [inline]
iptunnel_xmit+0x432/0x4a0 net/ipv4/ip_tunnel_core.c:87
ip_tunnel_xmit+0x1477/0x1750 net/ipv4/ip_tunnel.c:831
__gre_xmit net/ipv4/ip_gre.c:469 [inline]
ipgre_xmit+0x516/0x570 net/ipv4/ip_gre.c:662
__netdev_start_xmit include/linux/netdevice.h:4889 [inline]
netdev_start_xmit include/linux/netdevice.h:4903 [inline]
xmit_one net/core/dev.c:3544 [inline]
dev_hard_start_xmit+0x11b/0x3f0 net/core/dev.c:3560
__dev_queue_xmit+0xeee/0x1de0 net/core/dev.c:4340
dev_queue_xmit include/linux/netdevice.h:3082 [inline]
__bpf_tx_skb net/core/filter.c:2129 [inline]
__bpf_redirect_no_mac net/core/filter.c:2159 [inline]
__bpf_redirect+0x723/0x9c0 net/core/filter.c:2182
____bpf_clone_redirect net/core/filter.c:2453 [inline]
bpf_clone_redirect+0x16c/0x1d0 net/core/filter.c:2425
___bpf_prog_run+0xd7d/0x41e0 kernel/bpf/core.c:1954
__bpf_prog_run512+0x74/0xa0 kernel/bpf/core.c:2195
bpf_dispatcher_nop_func include/linux/bpf.h:1181 [inline]
__bpf_prog_run include/linux/filter.h:609 [inline]
bpf_prog_run include/linux/filter.h:616 [inline]
bpf_test_run+0x15d/0x3d0 net/bpf/test_run.c:423
bpf_prog_test_run_skb+0x77b/0xa00 net/bpf/test_run.c:1045
bpf_prog_test_run+0x265/0x3d0 kernel/bpf/syscall.c:3996
__sys_bpf+0x3af/0x780 kernel/bpf/syscall.c:5353
__do_sys_bpf kernel/bpf/syscall.c:5439 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5437 [inline]
__x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5437
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff8881353df170 of 8 bytes by task 30249 on cpu 0:
iptunnel_xmit_stats include/net/ip_tunnels.h:493 [inline]
iptunnel_xmit+0x432/0x4a0 net/ipv4/ip_tunnel_core.c:87
ip_tunnel_xmit+0x1477/0x1750 net/ipv4/ip_tunnel.c:831
__gre_xmit net/ipv4/ip_gre.c:469 [inline]
ipgre_xmit+0x516/0x570 net/ipv4/ip_gre.c:662
__netdev_start_xmit include/linux/netdevice.h:4889 [inline]
netdev_start_xmit include/linux/netdevice.h:4903 [inline]
xmit_one net/core/dev.c:3544 [inline]
dev_hard_start_xmit+0x11b/0x3f0 net/core/dev.c:3560
__dev_queue_xmit+0xeee/0x1de0 net/core/dev.c:4340
dev_queue_xmit include/linux/netdevice.h:3082 [inline]
__bpf_tx_skb net/core/filter.c:2129 [inline]
__bpf_redirect_no_mac net/core/filter.c:2159 [inline]
__bpf_redirect+0x723/0x9c0 net/core/filter.c:2182
____bpf_clone_redirect net/core/filter.c:2453 [inline]
bpf_clone_redirect+0x16c/0x1d0 net/core/filter.c:2425
___bpf_prog_run+0xd7d/0x41e0 kernel/bpf/core.c:1954
__bpf_prog_run512+0x74/0xa0 kernel/bpf/core.c:2195
bpf_dispatcher_nop_func include/linux/bpf.h:1181 [inline]
__bpf_prog_run include/linux/filter.h:609 [inline]
bpf_prog_run include/linux/filter.h:616 [inline]
bpf_test_run+0x15d/0x3d0 net/bpf/test_run.c:423
bpf_prog_test_run_skb+0x77b/0xa00 net/bpf/test_run.c:1045
bpf_prog_test_run+0x265/0x3d0 kernel/bpf/syscall.c:3996
__sys_bpf+0x3af/0x780 kernel/bpf/syscall.c:5353
__do_sys_bpf kernel/bpf/syscall.c:5439 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5437 [inline]
__x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5437
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000018830 -> 0x0000000000018831

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 30249 Comm: syz-executor.4 Not tainted 6.5.0-syzkaller-11704-g3f86ed6e #0

Fixes: 039f5062 ("ip_tunnel: Move stats update to iptunnel_xmit()")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

team interface has used a dynamic lockdep key to avoid false-positive
lockdep deadlock detection. Virtual interfaces such as team usually
have their own lock for protecting private data.
These interfaces can be nested.
team0
  |
team1

Each interface's lock is actually different(team0->lock and team1->lock).
So,
mutex_lock(&team0->lock);
mutex_lock(&team1->lock);
mutex_unlock(&team1->lock);
mutex_unlock(&team0->lock);
The above case is absolutely safe. But lockdep warns about deadlock.
Because the lockdep understands these two locks are same. This is a
false-positive lockdep warning.

So, in order to avoid this problem, the team interfaces started to use
dynamic lockdep key. The false-positive problem was fixed, but it
introduced a new problem.

When the new team virtual interface is created, it registers a dynamic
lockdep key(creates dynamic lockdep key) and uses it. But there is the
limitation of the number of lockdep keys.
So, If so many team interfaces are created, it consumes all lockdep keys.
Then, the lockdep stops to work and warns about it.

In order to fix this problem, team interfaces use the subclass instead
of the dynamic key. So, when a new team interface is created, it doesn't
register(create) a new lockdep, but uses existed subclass key instead.
It is already used by the bonding interface for a similar case.

As the bonding interface does, the subclass variable is the same as
the 'dev->nested_level'. This variable indicates the depth in the stacked
interface graph.

The 'dev->nested_level' is protected by RTNL and RCU.
So, 'mutex_lock_nested()' for 'team->lock' requires RTNL or RCU.
In the current code, 'team->lock' is usually acquired under RTNL, there is
no problem with using 'dev->nested_level'.

The 'team_nl_team_get()' and The 'lb_stats_refresh()' functions acquire
'team->lock' without RTNL.
But these don't iterate their own ports nested so they don't need nested
lock.

Reproducer:
   for i in {0..1000}
   do
           ip link add team$i type team
           ip link add dummy$i master team$i type dummy
           ip link set dummy$i up
           ip link set team$i up
   done

Splat looks like:
   BUG: MAX_LOCKDEP_ENTRIES too low!
   turning off the locking correctness validator.
   Please attach the output of /proc/lock_stat to the bug report
   CPU: 0 PID: 4104 Comm: ip Not tainted 6.5.0-rc7+ #45
   Call Trace:
    <TASK>
   dump_stack_lvl+0x64/0xb0
   add_lock_to_list+0x30d/0x5e0
   check_prev_add+0x73a/0x23a0
   ...
   sock_def_readable+0xfe/0x4f0
   netlink_broadcast+0x76b/0xac0
   nlmsg_notify+0x69/0x1d0
   dev_open+0xed/0x130
   ...

Reported-by: syzbot+9bbbacfbf1e04d5221f7@syzkaller.appspotmail.com
Fixes: 369f61be ("team: fix nested locking lockdep warning")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

__skb_get_hash_symmetric() was added to compute a symmetric hash over
the protocol, addresses and transport ports, by commit eb70db87
("packet: Use symmetric hash for PACKET_FANOUT_HASH."). It uses
flow_keys_dissector_symmetric_keys as the flow_dissector to incorporate
IPv4 addresses, IPv6 addresses and ports. However, it should not specify
the flag as FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL, which stops further
dissection when an IPv6 flow label is encountered, making transport
ports not being incorporated in such case.

As a consequence, the symmetric hash is based on 5-tuple for IPv4 but
3-tuple for IPv6 when flow label is present. It caused a few problems,
e.g. when nft symhash and openvswitch l4_sym rely on the symmetric hash
to perform load balancing as different L4 flows between two given IPv6
addresses would always get the same symmetric hash, leading to uneven
traffic distribution.

Removing the use of FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL makes sure the
symmetric hash is based on 5-tuple for both IPv4 and IPv6 consistently.

Fixes: eb70db87 ("packet: Use symmetric hash for PACKET_FANOUT_HASH.")
Reported-by: Lars Ekman <uablrek@gmail.com>
Closes: https://github.com/antrea-io/antrea/issues/5457Signed-off-by: Quan Tian <qtian@vmware.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Change the minimum value of RX/TX descriptors to 64 to enable setting the rx/tx
value between 64 and 80. All igb devices can use as low as 64 descriptors.
This change will unify igb with other drivers.
Based on commit 7b1be198 ("e1000e: lower ring minimum size to 64")

Fixes: 9d5c8243 ("igb: PCI-Express 82575 Gigabit Ethernet driver")
Signed-off-by: Olga Zaborska <olga.zaborska@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

Change the minimum value of RX/TX descriptors to 64 to enable setting the rx/tx
value between 64 and 80. All igbvf devices can use as low as 64 descriptors.
This change will unify igbvf with other drivers.
Based on commit 7b1be198 ("e1000e: lower ring minimum size to 64")

Fixes: d4e0fe01 ("igbvf: add new driver to support 82576 virtual functions")
Signed-off-by: Olga Zaborska <olga.zaborska@intel.com>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

Change the minimum value of RX/TX descriptors to 64 to enable setting the rx/tx
value between 64 and 80. All igc devices can use as low as 64 descriptors.
This change will unify igc with other drivers.
Based on commit 7b1be198 ("e1000e: lower ring minimum size to 64")

Fixes: 0507ef8a ("igc: Add transmit and receive fastpath and interrupt handlers")
Signed-off-by: Olga Zaborska <olga.zaborska@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

The smq value used in the CN10K NIX AQ instruction enqueue mailbox
handler was truncated to 9-bit value from 10-bit value because of
typecasting the CN10K mbox request structure to the CN9K structure.
Though this hasn't caused any problems when programming the NIX SQ
context to the HW because the context structure is the same size.
However, this causes a problem when accessing the structure parameters.
This patch reads the right smq value for each platform.

Fixes: 30077d21 ("octeontx2-af: cn10k: Update NIX/NPA context structure")
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is a follow up of commit 915d975b ("net: deal with integer
overflows in kmalloc_reserve()") based on David Laight feedback.

Back in 2010, I failed to realize malicious users could set dev->mtu
to arbitrary values. This mtu has been since limited to 0x7fffffff but
regardless of how big dev->mtu is, it makes no sense for igmpv3_newpack()
to allocate more than IP_MAX_MTU and risk various skb fields overflows.

Fixes: 57e1ab6e ("igmp: refine skb allocations")
Link: https://lore.kernel.org/netdev/d273628df80f45428e739274ab9ecb72@AcuMS.aculab.com/Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: David Laight <David.Laight@ACULAB.COM>
Cc: Kyle Zeng <zengyhkyle@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This reverts commit ab046a5d.

It was trying to work around an issue at the crypto layer by excluding
ASYNC implementations of gcm(aes), because a bug in the AESNI version
caused reordering when some requests bypassed the cryptd queue while
older requests were still pending on the queue.

This was fixed by commit 38b2f68b ("crypto: aesni - Fix cryptd
reordering problem on gcm"), which pre-dates ab046a5d.

Herbert Xu confirmed that all ASYNC implementations are expected to
maintain the ordering of completions wrt requests, so we can use them
in MACsec.

On my test machine, this restores the performance of a single netperf
instance, from 1.4Gbps to 4.4Gbps.

Link: https://lore.kernel.org/netdev/9328d206c5d9f9239cae27e62e74de40b258471d.1692279161.git.sd@queasysnail.net/T/
Link: https://lore.kernel.org/netdev/1b0cec71-d084-8153-2ba4-72ce71abeb65@byu.edu/
Link: https://lore.kernel.org/netdev/d335ddaa-18dc-f9f0-17ee-9783d3b2ca29@mailbox.tu-dresden.de/
Fixes: ab046a5d ("net: macsec: preserve ingress frame ordering")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/r/11c952469d114db6fb29242e1d9545e61f52f512.1693757159.git.sd@queasysnail.netSigned-off-by: Paolo Abeni <pabeni@redhat.com>

kcm_exit_net() should call mutex_destroy() on knet->mutex. This is especially
needed if CONFIG_DEBUG_MUTEXES is enabled.

Fixes: ab7ac4eb ("kcm: Kernel Connection Multiplexor module")
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Link: https://lore.kernel.org/r/20230902170708.1727999-1-syoshida@redhat.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

When the plug qdisc is used as a class of the qfq qdisc it could trigger a
UAF. This issue can be reproduced with following commands:

  tc qdisc add dev lo root handle 1: qfq
  tc class add dev lo parent 1: classid 1:1 qfq weight 1 maxpkt 512
  tc qdisc add dev lo parent 1:1 handle 2: plug
  tc filter add dev lo parent 1: basic classid 1:1
  ping -c1 127.0.0.1

and boom:

[  285.353793] BUG: KASAN: slab-use-after-free in qfq_dequeue+0xa7/0x7f0
[  285.354910] Read of size 4 at addr ffff8880bad312a8 by task ping/144
[  285.355903]
[  285.356165] CPU: 1 PID: 144 Comm: ping Not tainted 6.5.0-rc3+ #4
[  285.357112] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
[  285.358376] Call Trace:
[  285.358773]  <IRQ>
[  285.359109]  dump_stack_lvl+0x44/0x60
[  285.359708]  print_address_description.constprop.0+0x2c/0x3c0
[  285.360611]  kasan_report+0x10c/0x120
[  285.361195]  ? qfq_dequeue+0xa7/0x7f0
[  285.361780]  qfq_dequeue+0xa7/0x7f0
[  285.362342]  __qdisc_run+0xf1/0x970
[  285.362903]  net_tx_action+0x28e/0x460
[  285.363502]  __do_softirq+0x11b/0x3de
[  285.364097]  do_softirq.part.0+0x72/0x90
[  285.364721]  </IRQ>
[  285.365072]  <TASK>
[  285.365422]  __local_bh_enable_ip+0x77/0x90
[  285.366079]  __dev_queue_xmit+0x95f/0x1550
[  285.366732]  ? __pfx_csum_and_copy_from_iter+0x10/0x10
[  285.367526]  ? __pfx___dev_queue_xmit+0x10/0x10
[  285.368259]  ? __build_skb_around+0x129/0x190
[  285.368960]  ? ip_generic_getfrag+0x12c/0x170
[  285.369653]  ? __pfx_ip_generic_getfrag+0x10/0x10
[  285.370390]  ? csum_partial+0x8/0x20
[  285.370961]  ? raw_getfrag+0xe5/0x140
[  285.371559]  ip_finish_output2+0x539/0xa40
[  285.372222]  ? __pfx_ip_finish_output2+0x10/0x10
[  285.372954]  ip_output+0x113/0x1e0
[  285.373512]  ? __pfx_ip_output+0x10/0x10
[  285.374130]  ? icmp_out_count+0x49/0x60
[  285.374739]  ? __pfx_ip_finish_output+0x10/0x10
[  285.375457]  ip_push_pending_frames+0xf3/0x100
[  285.376173]  raw_sendmsg+0xef5/0x12d0
[  285.376760]  ? do_syscall_64+0x40/0x90
[  285.377359]  ? __static_call_text_end+0x136578/0x136578
[  285.378173]  ? do_syscall_64+0x40/0x90
[  285.378772]  ? kasan_enable_current+0x11/0x20
[  285.379469]  ? __pfx_raw_sendmsg+0x10/0x10
[  285.380137]  ? __sock_create+0x13e/0x270
[  285.380673]  ? __sys_socket+0xf3/0x180
[  285.381174]  ? __x64_sys_socket+0x3d/0x50
[  285.381725]  ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.382425]  ? __rcu_read_unlock+0x48/0x70
[  285.382975]  ? ip4_datagram_release_cb+0xd8/0x380
[  285.383608]  ? __pfx_ip4_datagram_release_cb+0x10/0x10
[  285.384295]  ? preempt_count_sub+0x14/0xc0
[  285.384844]  ? __list_del_entry_valid+0x76/0x140
[  285.385467]  ? _raw_spin_lock_bh+0x87/0xe0
[  285.386014]  ? __pfx__raw_spin_lock_bh+0x10/0x10
[  285.386645]  ? release_sock+0xa0/0xd0
[  285.387148]  ? preempt_count_sub+0x14/0xc0
[  285.387712]  ? freeze_secondary_cpus+0x348/0x3c0
[  285.388341]  ? aa_sk_perm+0x177/0x390
[  285.388856]  ? __pfx_aa_sk_perm+0x10/0x10
[  285.389441]  ? check_stack_object+0x22/0x70
[  285.390032]  ? inet_send_prepare+0x2f/0x120
[  285.390603]  ? __pfx_inet_sendmsg+0x10/0x10
[  285.391172]  sock_sendmsg+0xcc/0xe0
[  285.391667]  __sys_sendto+0x190/0x230
[  285.392168]  ? __pfx___sys_sendto+0x10/0x10
[  285.392727]  ? kvm_clock_get_cycles+0x14/0x30
[  285.393328]  ? set_normalized_timespec64+0x57/0x70
[  285.393980]  ? _raw_spin_unlock_irq+0x1b/0x40
[  285.394578]  ? __x64_sys_clock_gettime+0x11c/0x160
[  285.395225]  ? __pfx___x64_sys_clock_gettime+0x10/0x10
[  285.395908]  ? _copy_to_user+0x3e/0x60
[  285.396432]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.397086]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.397734]  ? do_syscall_64+0x71/0x90
[  285.398258]  __x64_sys_sendto+0x74/0x90
[  285.398786]  do_syscall_64+0x64/0x90
[  285.399273]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.399949]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.400605]  ? do_syscall_64+0x71/0x90
[  285.401124]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.401807] RIP: 0033:0x495726
[  285.402233] Code: ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 09
[  285.404683] RSP: 002b:00007ffcc25fb618 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[  285.405677] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 0000000000495726
[  285.406628] RDX: 0000000000000040 RSI: 0000000002518750 RDI: 0000000000000000
[  285.407565] RBP: 00000000005205ef R08: 00000000005f8838 R09: 000000000000001c
[  285.408523] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002517634
[  285.409460] R13: 00007ffcc25fb6f0 R14: 0000000000000003 R15: 0000000000000000
[  285.410403]  </TASK>
[  285.410704]
[  285.410929] Allocated by task 144:
[  285.411402]  kasan_save_stack+0x1e/0x40
[  285.411926]  kasan_set_track+0x21/0x30
[  285.412442]  __kasan_slab_alloc+0x55/0x70
[  285.412973]  kmem_cache_alloc_node+0x187/0x3d0
[  285.413567]  __alloc_skb+0x1b4/0x230
[  285.414060]  __ip_append_data+0x17f7/0x1b60
[  285.414633]  ip_append_data+0x97/0xf0
[  285.415144]  raw_sendmsg+0x5a8/0x12d0
[  285.415640]  sock_sendmsg+0xcc/0xe0
[  285.416117]  __sys_sendto+0x190/0x230
[  285.416626]  __x64_sys_sendto+0x74/0x90
[  285.417145]  do_syscall_64+0x64/0x90
[  285.417624]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.418306]
[  285.418531] Freed by task 144:
[  285.418960]  kasan_save_stack+0x1e/0x40
[  285.419469]  kasan_set_track+0x21/0x30
[  285.419988]  kasan_save_free_info+0x27/0x40
[  285.420556]  ____kasan_slab_free+0x109/0x1a0
[  285.421146]  kmem_cache_free+0x1c2/0x450
[  285.421680]  __netif_receive_skb_core+0x2ce/0x1870
[  285.422333]  __netif_receive_skb_one_core+0x97/0x140
[  285.423003]  process_backlog+0x100/0x2f0
[  285.423537]  __napi_poll+0x5c/0x2d0
[  285.424023]  net_rx_action+0x2be/0x560
[  285.424510]  __do_softirq+0x11b/0x3de
[  285.425034]
[  285.425254] The buggy address belongs to the object at ffff8880bad31280
[  285.425254]  which belongs to the cache skbuff_head_cache of size 224
[  285.426993] The buggy address is located 40 bytes inside of
[  285.426993]  freed 224-byte region [ffff8880bad31280, ffff8880bad31360)
[  285.428572]
[  285.428798] The buggy address belongs to the physical page:
[  285.429540] page:00000000f4b77674 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xbad31
[  285.430758] flags: 0x100000000000200(slab|node=0|zone=1)
[  285.431447] page_type: 0xffffffff()
[  285.431934] raw: 0100000000000200 ffff88810094a8c0 dead000000000122 0000000000000000
[  285.432757] raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
[  285.433562] page dumped because: kasan: bad access detected
[  285.434144]
[  285.434320] Memory state around the buggy address:
[  285.434828]  ffff8880bad31180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.435580]  ffff8880bad31200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.436264] >ffff8880bad31280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  285.436777]                                   ^
[  285.437106]  ffff8880bad31300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
[  285.437616]  ffff8880bad31380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.438126] ==================================================================
[  285.438662] Disabling lock debugging due to kernel taint

Fix this by:
1. Changing sch_plug's .peek handler to qdisc_peek_dequeued(), a
function compatible with non-work-conserving qdiscs
2. Checking the return value of qdisc_dequeue_peeked() in sch_qfq.

Fixes: 462dbc91 ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Reported-by: valis <sec@valis.email>
Signed-off-by: valis <sec@valis.email>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20230901162237.11525-1-jhs@mojatatu.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Kuniyuki Iwashima says:

====================
af_unix: Fix four data-races.

While running syzkaller, KCSAN reported 3 data-races with
systemd-coredump using AF_UNIX sockets.

This series fixes the three and another one inspiered by
one of the reports.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

As with sk->sk_shutdown shown in the previous patch, sk->sk_err can be
read locklessly by unix_dgram_sendmsg().

Let's use READ_ONCE() for sk_err as well.

Note that the writer side is marked by commit cc04410a ("af_unix:
annotate lockless accesses to sk->sk_err").

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sk->sk_shutdown is changed under unix_state_lock(sk), but
unix_dgram_sendmsg() calls two functions to read sk_shutdown locklessly.

  sock_alloc_send_pskb
  `- sock_wait_for_wmem

Let's use READ_ONCE() there.

Note that the writer side was marked by commit e1d09c2c ("af_unix:
Fix data races around sk->sk_shutdown.").

BUG: KCSAN: data-race in sock_alloc_send_pskb / unix_release_sock

write (marked) to 0xffff8880069af12c of 1 bytes by task 1 on cpu 1:
 unix_release_sock+0x75c/0x910 net/unix/af_unix.c:631
 unix_release+0x59/0x80 net/unix/af_unix.c:1053
 __sock_release+0x7d/0x170 net/socket.c:654
 sock_close+0x19/0x30 net/socket.c:1386
 __fput+0x2a3/0x680 fs/file_table.c:384
 ____fput+0x15/0x20 fs/file_table.c:412
 task_work_run+0x116/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x174/0x180 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:297
 do_syscall_64+0x4b/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

read to 0xffff8880069af12c of 1 bytes by task 28650 on cpu 0:
 sock_alloc_send_pskb+0xd2/0x620 net/core/sock.c:2767
 unix_dgram_sendmsg+0x2f8/0x14f0 net/unix/af_unix.c:1944
 unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline]
 unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg+0x148/0x160 net/socket.c:748
 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2494
 ___sys_sendmsg+0xc6/0x140 net/socket.c:2548
 __sys_sendmsg+0x94/0x140 net/socket.c:2577
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x45/0x50 net/socket.c:2584
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

value changed: 0x00 -> 0x03

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 28650 Comm: systemd-coredum Not tainted 6.4.0-11989-g68433066 #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

unix_tot_inflight is changed under spin_lock(unix_gc_lock), but
unix_release_sock() reads it locklessly.

Let's use READ_ONCE() for unix_tot_inflight.

Note that the writer side was marked by commit 9d6d7f1c ("af_unix:
annote lockless accesses to unix_tot_inflight & gc_in_progress")

BUG: KCSAN: data-race in unix_inflight / unix_release_sock

write (marked) to 0xffffffff871852b8 of 4 bytes by task 123 on cpu 1:
 unix_inflight+0x130/0x180 net/unix/scm.c:64
 unix_attach_fds+0x137/0x1b0 net/unix/scm.c:123
 unix_scm_to_skb net/unix/af_unix.c:1832 [inline]
 unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1955
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0x148/0x160 net/socket.c:747
 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2493
 ___sys_sendmsg+0xc6/0x140 net/socket.c:2547
 __sys_sendmsg+0x94/0x140 net/socket.c:2576
 __do_sys_sendmsg net/socket.c:2585 [inline]
 __se_sys_sendmsg net/socket.c:2583 [inline]
 __x64_sys_sendmsg+0x45/0x50 net/socket.c:2583
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

read to 0xffffffff871852b8 of 4 bytes by task 4891 on cpu 0:
 unix_release_sock+0x608/0x910 net/unix/af_unix.c:671
 unix_release+0x59/0x80 net/unix/af_unix.c:1058
 __sock_release+0x7d/0x170 net/socket.c:653
 sock_close+0x19/0x30 net/socket.c:1385
 __fput+0x179/0x5e0 fs/file_table.c:321
 ____fput+0x15/0x20 fs/file_table.c:349
 task_work_run+0x116/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x174/0x180 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:297
 do_syscall_64+0x4b/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4891 Comm: systemd-coredum Not tainted 6.4.0-rc5-01219-gfa0e21fa #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014

Fixes: 9305cfa4 ("[AF_UNIX]: Make unix_tot_inflight counter non-atomic")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

user->unix_inflight is changed under spin_lock(unix_gc_lock),
but too_many_unix_fds() reads it locklessly.

Let's annotate the write/read accesses to user->unix_inflight.

BUG: KCSAN: data-race in unix_attach_fds / unix_inflight

write to 0xffffffff8546f2d0 of 8 bytes by task 44798 on cpu 1:
 unix_inflight+0x157/0x180 net/unix/scm.c:66
 unix_attach_fds+0x147/0x1e0 net/unix/scm.c:123
 unix_scm_to_skb net/unix/af_unix.c:1827 [inline]
 unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950
 unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline]
 unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg+0x148/0x160 net/socket.c:748
 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2494
 ___sys_sendmsg+0xc6/0x140 net/socket.c:2548
 __sys_sendmsg+0x94/0x140 net/socket.c:2577
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x45/0x50 net/socket.c:2584
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

read to 0xffffffff8546f2d0 of 8 bytes by task 44814 on cpu 0:
 too_many_unix_fds net/unix/scm.c:101 [inline]
 unix_attach_fds+0x54/0x1e0 net/unix/scm.c:110
 unix_scm_to_skb net/unix/af_unix.c:1827 [inline]
 unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950
 unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline]
 unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg+0x148/0x160 net/socket.c:748
 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2494
 ___sys_sendmsg+0xc6/0x140 net/socket.c:2548
 __sys_sendmsg+0x94/0x140 net/socket.c:2577
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x45/0x50 net/socket.c:2584
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

value changed: 0x000000000000000c -> 0x000000000000000d

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 44814 Comm: systemd-coredum Not tainted 6.4.0-11989-g68433066 #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014

Fixes: 712f4aad ("unix: properly account for FDs passed over unix sockets")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Heiko Carstens reported that SCM_PIDFD does not work with MSG_CMSG_COMPAT
because scm_pidfd_recv() always checks msg_controllen against sizeof(struct
cmsghdr).

We need to use sizeof(struct compat_cmsghdr) for the compat case.

Fixes: 5e2ff670 ("scm: add SO_PASSPIDFD and SCM_PIDFD")
Reported-by: Heiko Carstens <hca@linux.ibm.com>
Closes: https://lore.kernel.org/netdev/20230901200517.8742-A-hca@linux.ibm.com/Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some corporate proxies block our current NIPA URLs because
they use a free / shady DNS domain. As suggested by Jesse
we got a new DNS entry from Konstantin - netdev.bots.linux.dev,
use it.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The patchwork states are largely self-explanatory but small
ambiguities may still come up. Document how we interpret
the states in networking.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

There is a race where skb's from the sk_psock_backlog can be referenced
after userspace side has already skb_consumed() the sk_buff and its refcnt
dropped to zer0 causing use after free.

The flow is the following:

  while ((skb = skb_peek(&psock->ingress_skb))
    sk_psock_handle_Skb(psock, skb, ..., ingress)
    if (!ingress) ...
    sk_psock_skb_ingress
       sk_psock_skb_ingress_enqueue(skb)
          msg->skb = skb
          sk_psock_queue_msg(psock, msg)
    skb_dequeue(&psock->ingress_skb)

The sk_psock_queue_msg() puts the msg on the ingress_msg queue. This is
what the application reads when recvmsg() is called. An application can
read this anytime after the msg is placed on the queue. The recvmsg hook
will also read msg->skb and then after user space reads the msg will call
consume_skb(skb) on it effectively free'ing it.

But, the race is in above where backlog queue still has a reference to
the skb and calls skb_dequeue(). If the skb_dequeue happens after the
user reads and free's the skb we have a use after free.

The !ingress case does not suffer from this problem because it uses
sendmsg_*(sk, msg) which does not pass the sk_buff further down the
stack.

The following splat was observed with 'test_progs -t sockmap_listen':

  [ 1022.710250][ T2556] general protection fault, ...
  [...]
  [ 1022.712830][ T2556] Workqueue: events sk_psock_backlog
  [ 1022.713262][ T2556] RIP: 0010:skb_dequeue+0x4c/0x80
  [ 1022.713653][ T2556] Code: ...
  [...]
  [ 1022.720699][ T2556] Call Trace:
  [ 1022.720984][ T2556]  <TASK>
  [ 1022.721254][ T2556]  ? die_addr+0x32/0x80^M
  [ 1022.721589][ T2556]  ? exc_general_protection+0x25a/0x4b0
  [ 1022.722026][ T2556]  ? asm_exc_general_protection+0x22/0x30
  [ 1022.722489][ T2556]  ? skb_dequeue+0x4c/0x80
  [ 1022.722854][ T2556]  sk_psock_backlog+0x27a/0x300
  [ 1022.723243][ T2556]  process_one_work+0x2a7/0x5b0
  [ 1022.723633][ T2556]  worker_thread+0x4f/0x3a0
  [ 1022.723998][ T2556]  ? __pfx_worker_thread+0x10/0x10
  [ 1022.724386][ T2556]  kthread+0xfd/0x130
  [ 1022.724709][ T2556]  ? __pfx_kthread+0x10/0x10
  [ 1022.725066][ T2556]  ret_from_fork+0x2d/0x50
  [ 1022.725409][ T2556]  ? __pfx_kthread+0x10/0x10
  [ 1022.725799][ T2556]  ret_from_fork_asm+0x1b/0x30
  [ 1022.726201][ T2556]  </TASK>

To fix we add an skb_get() before passing the skb to be enqueued in the
engress queue. This bumps the skb->users refcnt so that consume_skb()
and kfree_skb will not immediately free the sk_buff. With this we can
be sure the skb is still around when we do the dequeue. Then we just
need to decrement the refcnt or free the skb in the backlog case which
we do by calling kfree_skb() on the ingress case as well as the sendmsg
case.

Before locking change from fixes tag we had the sock locked so we
couldn't race with user and there was no issue here.

Fixes: 799aa7f9 ("skmsg: Avoid lock_sock() in sk_psock_backlog()")
Reported-by: Jiri Olsa  <jolsa@kernel.org>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Xu Kuohai <xukuohai@huawei.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230901202137.214666-1-john.fastabend@gmail.com

Previously, the defines for phy_device flags in the Micrel driver were
ambiguous in their representation. They were intended to be bit masks
but were mistakenly defined as bit positions. This led to the following
issues:

- MICREL_KSZ8_P1_ERRATA, designated for KSZ88xx switches, overlapped
  with MICREL_PHY_FXEN and MICREL_PHY_50MHZ_CLK.
- Due to this overlap, the code path for MICREL_PHY_FXEN, tailored for
  the KSZ8041 PHY, was not executed for KSZ88xx PHYs.
- Similarly, the code associated with MICREL_PHY_50MHZ_CLK wasn't
  triggered for KSZ88xx.

To rectify this, all three flags have now been explicitly converted to
use the `BIT()` macro, ensuring they are defined as bit masks and
preventing potential overlaps in the future.

Fixes: 49011e0c ("net: phy: micrel: ksz886x/ksz8081: add cabletest support")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

The existing code incorrectly casted a negative value (the result of a
subtraction) to an unsigned value without checking. For example, if
/proc/sys/net/ipv6/conf/*/temp_prefered_lft was set to 1, the preferred
lifetime would jump to 4 billion seconds. On my machine and network the
shortest lifetime that avoided underflow was 3 seconds.

Fixes: 76506a98 ("IPv6: fix DESYNC_FACTOR")
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The veth_xmit function returns NETDEV_TX_OK even when packets are dropped.
This behavior leads to incorrect calculations of statistics counts, as
well as things like txq->trans_start updates.

Fixes: e314dbdc ("[NET]: Virtual ethernet device driver.")
Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

gve_rx_append_frags() is able to build skbs chained with frag_list,
like GRO engine.

Problem is that shinfo->frag_list should only be used
for the head of the chain.

All other links should use skb->next pointer.

Otherwise, built skbs are not valid and can cause crashes.

Equivalent code in GRO (skb_gro_receive()) is:

    if (NAPI_GRO_CB(p)->last == p)
        skb_shinfo(p)->frag_list = skb;
    else
        NAPI_GRO_CB(p)->last->next = skb;
    NAPI_GRO_CB(p)->last = skb;

Fixes: 9b8dd5e5 ("gve: DQO: Add RX path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Bailey Forrest <bcf@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Catherine Sullivan <csully@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Blamed commit changed:
    ptr = kmalloc(size);
    if (ptr)
      size = ksize(ptr);

to:
    size = kmalloc_size_roundup(size);
    ptr = kmalloc(size);

This allowed various crash as reported by syzbot [1]
and Kyle Zeng.

Problem is that if @size is bigger than 0x80000001,
kmalloc_size_roundup(size) returns 2^32.

kmalloc_reserve() uses a 32bit variable (obj_size),
so 2^32 is truncated to 0.

kmalloc(0) returns ZERO_SIZE_PTR which is not handled by
skb allocations.

Following trace can be triggered if a netdev->mtu is set
close to 0x7fffffff

We might in the future limit netdev->mtu to more sensible
limit (like KMALLOC_MAX_SIZE).

This patch is based on a syzbot report, and also a report
and tentative fix from Kyle Zeng.

[1]
BUG: KASAN: user-memory-access in __build_skb_around net/core/skbuff.c:294 [inline]
BUG: KASAN: user-memory-access in __alloc_skb+0x3c4/0x6e8 net/core/skbuff.c:527
Write of size 32 at addr 00000000fffffd10 by task syz-executor.4/22554

CPU: 1 PID: 22554 Comm: syz-executor.4 Not tainted 6.1.39-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
Call trace:
dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:279
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:286
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x120/0x1a0 lib/dump_stack.c:106
print_report+0xe4/0x4b4 mm/kasan/report.c:398
kasan_report+0x150/0x1ac mm/kasan/report.c:495
kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:189
memset+0x40/0x70 mm/kasan/shadow.c:44
__build_skb_around net/core/skbuff.c:294 [inline]
__alloc_skb+0x3c4/0x6e8 net/core/skbuff.c:527
alloc_skb include/linux/skbuff.h:1316 [inline]
igmpv3_newpack+0x104/0x1088 net/ipv4/igmp.c:359
add_grec+0x81c/0x1124 net/ipv4/igmp.c:534
igmpv3_send_cr net/ipv4/igmp.c:667 [inline]
igmp_ifc_timer_expire+0x1b0/0x1008 net/ipv4/igmp.c:810
call_timer_fn+0x1c0/0x9f0 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers+0x54c/0x710 kernel/time/timer.c:1790
run_timer_softirq+0x28/0x4c kernel/time/timer.c:1803
_stext+0x380/0xfbc
____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:79
call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:891
do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:84
invoke_softirq kernel/softirq.c:437 [inline]
__irq_exit_rcu+0x1c0/0x4cc kernel/softirq.c:683
irq_exit_rcu+0x14/0x78 kernel/softirq.c:695
el0_interrupt+0x7c/0x2e0 arch/arm64/kernel/entry-common.c:717
__el0_irq_handler_common+0x18/0x24 arch/arm64/kernel/entry-common.c:724
el0t_64_irq_handler+0x10/0x1c arch/arm64/kernel/entry-common.c:729
el0t_64_irq+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Fixes: 12d6c1d3 ("skbuff: Proactively round up to kmalloc bucket size")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Kyle Zeng <zengyhkyle@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>