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  1. 18 Nov, 2021 6 commits
  3. 17 Nov, 2021 15 commits
  5. 16 Nov, 2021 19 commits
    • Raed Salem's avatar
      net/mlx5: E-Switch, return error if encap isn't supported · c4c31767
      Raed Salem authored 
      On regular ConnectX HCAs getting encap mode isn't supported when the
E-Switch is in NONE mode. Current code would return no error code when
trying to get encap mode in such case which is wrong.

Fix by returning error value to indicate failure to caller in such case.

Fixes: 8e0aa4bc ("net/mlx5: E-switch, Protect eswitch mode changes")
Signed-off-by: default avatarRaed Salem <raeds@nvidia.com>
Reviewed-by: default avatarMark Bloch <mbloch@nvidia.com>
Reviewed-by: default avatarMaor Dickman <maord@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      c4c31767
    • Maher Sanalla's avatar
      net/mlx5: Lag, update tracker when state change event received · ae396d85
      Maher Sanalla authored 
      Currently, In NETDEV_CHANGELOWERSTATE/NETDEV_CHANGEUPPERSTATE events
handling, tracking is not fully completed if the LAG device is not ready
at the time the events occur. But, we must keep track of the upper and
lower states after receiving the events because RoCE needs this info in
mlx5_lag_get_roce_netdev() - in order to return the corresponding port
that its running on. Returning the wrong (not most recent) port will lead
to gids table being incorrect.

For example: If during the attachment of a slave to the bond, the other
non-attached port performs pci_reload, then the LAG device is not ready,
but that should not result in dismissing attached slave tracker update
automatically (which is performed in mlx5_handle_changelowerstate()), Since
these events might not come later, which can lead to both bond ports
having tx_enabled=0 - which is not a valid state of LAG bond.

Fixes: 9b412cc3 ("net/mlx5e: Add LAG warning if bond slave is not lag master")
Signed-off-by: default avatarMaher Sanalla <msanalla@nvidia.com>
Reviewed-by: default avatarMark Bloch <mbloch@nvidia.com>
Reviewed-by: default avatarJianbo Liu <jianbol@nvidia.com>
Reviewed-by: default avatarRoi Dayan <roid@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      ae396d85
    • Roi Dayan's avatar
      net/mlx5e: CT, Fix multiple allocations and memleak of mod acts · 806401c2
      Roi Dayan authored 
      CT clear action offload adds additional mod hdr actions to the
flow's original mod actions in order to clear the registers which
hold ct_state.
When such flow also includes encap action, a neigh update event
can cause the driver to unoffload the flow and then reoffload it.

Each time this happens, the ct clear handling adds that same set
of mod hdr actions to reset ct_state until the max of mod hdr
actions is reached.

Also the driver never releases the allocated mod hdr actions and
causing a memleak.

Fix above two issues by moving CT clear mod acts allocation
into the parsing actions phase and only use it when offloading the rule.
The release of mod acts will be done in the normal flow_put().

 backtrace:
    [<000000007316e2f3>] krealloc+0x83/0xd0
    [<00000000ef157de1>] mlx5e_mod_hdr_alloc+0x147/0x300 [mlx5_core]
    [<00000000970ce4ae>] mlx5e_tc_match_to_reg_set_and_get_id+0xd7/0x240 [mlx5_core]
    [<0000000067c5fa17>] mlx5e_tc_match_to_reg_set+0xa/0x20 [mlx5_core]
    [<00000000d032eb98>] mlx5_tc_ct_entry_set_registers.isra.0+0x36/0xc0 [mlx5_core]
    [<00000000fd23b869>] mlx5_tc_ct_flow_offload+0x272/0x1f10 [mlx5_core]
    [<000000004fc24acc>] mlx5e_tc_offload_fdb_rules.part.0+0x150/0x620 [mlx5_core]
    [<00000000dc741c17>] mlx5e_tc_encap_flows_add+0x489/0x690 [mlx5_core]
    [<00000000e92e49d7>] mlx5e_rep_update_flows+0x6e4/0x9b0 [mlx5_core]
    [<00000000f60f5602>] mlx5e_rep_neigh_update+0x39a/0x5d0 [mlx5_core]

Fixes: 1ef3018f ("net/mlx5e: CT: Support clear action")
Signed-off-by: default avatarRoi Dayan <roid@nvidia.com>
Reviewed-by: default avatarPaul Blakey <paulb@nvidia.com>
Reviewed-by: default avatarMaor Dickman <maord@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      806401c2
    • Avihai Horon's avatar
      net/mlx5: Fix flow counters SF bulk query len · 38a54cae
      Avihai Horon authored 
      When doing a flow counters bulk query, the number of counters to query
must be aligned to 4. Current SF bulk query len is not aligned to 4,
which leads to an error when trying to query more than 4 counters.

Fix it by aligning SF bulk query len to 4.

Fixes: 2fdeb4f4 ("net/mlx5: Reduce flow counters bulk query buffer size for SFs")
Signed-off-by: default avatarAvihai Horon <avihaih@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      38a54cae
    • Mark Bloch's avatar
      net/mlx5: E-Switch, rebuild lag only when needed · 2eb0cb31
      Mark Bloch authored 
      A user can enable VFs without changing E-Switch mode, this can happen
when a user moves straight to switchdev mode and only once in switchdev
VFs are enabled via the sysfs interface.

The cited commit assumed this isn't possible and exposed a single
API function where the E-switch calls into the lag code, breaks the lag
and prevents any other lag operations to take place until the
E-switch update has ended.

Breaking the hardware lag when it isn't needed can make it such that
hardware lag can't be enabled again.

In the sysfs call path check if the current E-Switch mode is NONE,
in the context of the function it can only mean the E-Switch is moving
out of NONE mode and the hardware lag should be disabled and enabled
once the mode change has ended. If the mode isn't NONE it means
VFs are about to be enabled and such operation doesn't require
toggling the hardware lag.

Fixes: cac1eb2c ("net/mlx5: Lag, properly lock eswitch if needed")
Signed-off-by: default avatarMark Bloch <mbloch@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      2eb0cb31
    • Neta Ostrovsky's avatar
      net/mlx5: Update error handler for UCTX and UMEM · ba50cd94
      Neta Ostrovsky authored 
      In the fast unload flow, the device state is set to internal error,
which indicates that the driver started the destroy process.
In this case, when a destroy command is being executed, it should return
MLX5_CMD_STAT_OK.
Fix MLX5_CMD_OP_DESTROY_UCTX and MLX5_CMD_OP_DESTROY_UMEM to return OK
instead of EIO.

This fixes a call trace in the umem release process -
[ 2633.536695] Call Trace:
[ 2633.537518]  ib_uverbs_remove_one+0xc3/0x140 [ib_uverbs]
[ 2633.538596]  remove_client_context+0x8b/0xd0 [ib_core]
[ 2633.539641]  disable_device+0x8c/0x130 [ib_core]
[ 2633.540615]  __ib_unregister_device+0x35/0xa0 [ib_core]
[ 2633.541640]  ib_unregister_device+0x21/0x30 [ib_core]
[ 2633.542663]  __mlx5_ib_remove+0x38/0x90 [mlx5_ib]
[ 2633.543640]  auxiliary_bus_remove+0x1e/0x30 [auxiliary]
[ 2633.544661]  device_release_driver_internal+0x103/0x1f0
[ 2633.545679]  bus_remove_device+0xf7/0x170
[ 2633.546640]  device_del+0x181/0x410
[ 2633.547606]  mlx5_rescan_drivers_locked.part.10+0x63/0x160 [mlx5_core]
[ 2633.548777]  mlx5_unregister_device+0x27/0x40 [mlx5_core]
[ 2633.549841]  mlx5_uninit_one+0x21/0xc0 [mlx5_core]
[ 2633.550864]  remove_one+0x69/0xe0 [mlx5_core]
[ 2633.551819]  pci_device_remove+0x3b/0xc0
[ 2633.552731]  device_release_driver_internal+0x103/0x1f0
[ 2633.553746]  unbind_store+0xf6/0x130
[ 2633.554657]  kernfs_fop_write+0x116/0x190
[ 2633.555567]  vfs_write+0xa5/0x1a0
[ 2633.556407]  ksys_write+0x4f/0xb0
[ 2633.557233]  do_syscall_64+0x5b/0x1a0
[ 2633.558071]  entry_SYSCALL_64_after_hwframe+0x65/0xca
[ 2633.559018] RIP: 0033:0x7f9977132648
[ 2633.559821] Code: 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 55 6f 2d 00 8b 00 85 c0 75 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 49 89 d4 55
[ 2633.562332] RSP: 002b:00007fffb1a83888 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 2633.563472] RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007f9977132648
[ 2633.564541] RDX: 000000000000000c RSI: 000055b90546e230 RDI: 0000000000000001
[ 2633.565596] RBP: 000055b90546e230 R08: 00007f9977406860 R09: 00007f9977a54740
[ 2633.566653] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f99774056e0
[ 2633.567692] R13: 000000000000000c R14: 00007f9977400880 R15: 000000000000000c
[ 2633.568725] ---[ end trace 10b4fe52945e544d ]---

Fixes: 6a6fabbf ("net/mlx5: Update pci error handler entries and command translation")
Signed-off-by: default avatarNeta Ostrovsky <netao@nvidia.com>
Reviewed-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      ba50cd94
    • Yevgeny Kliteynik's avatar
      net/mlx5: DR, Fix check for unsupported fields in match param · 455832d4
      Yevgeny Kliteynik authored 
      The existing loop doesn't cast the buffer while scanning it, which
results in out-of-bounds read and failure to create the matcher.

Fixes: 941f1979 ("net/mlx5: DR, Add check for unsupported fields in match param")
Signed-off-by: default avatarYevgeny Kliteynik <kliteyn@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      455832d4
    • Yevgeny Kliteynik's avatar
      net/mlx5: DR, Handle eswitch manager and uplink vports separately · 9091b821
      Yevgeny Kliteynik authored 
      When querying eswitch manager vport capabilities as "other = 1",
we encounter a FW compatibility issue with older FW versions.
To maintain backward compatibility, eswitch manager vport should
be queried as "other = 0" vport both for ECPF and non-ECPF cases.

This patch fixes these queries and improves the code readability
by handling eswitch manager and uplink vports separately, avoiding
the excessive 'if' conditions. Also, uplink caps are stored similar
to esw manager and not as part of xarray.

Fixes: dd4acb2a ("net/mlx5: DR, Add missing query for vport 0")
Signed-off-by: default avatarYevgeny Kliteynik <kliteyn@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      9091b821
    • Valentine Fatiev's avatar
      net/mlx5e: nullify cq->dbg pointer in mlx5_debug_cq_remove() · 76ded29d
      Valentine Fatiev authored 
      Prior to this patch in case mlx5_core_destroy_cq() failed it proceeds
to rest of destroy operations. mlx5_core_destroy_cq() could be called again
by user and cause additional call of mlx5_debug_cq_remove().
cq->dbg was not nullify in previous call and cause the crash.

Fix it by nullify cq->dbg pointer after removal.

Also proceed to destroy operations only if FW return 0
for MLX5_CMD_OP_DESTROY_CQ command.

general protection fault, probably for non-canonical address 0x2000300004058: 0000 [#1] SMP PTI
CPU: 5 PID: 1228 Comm: python Not tainted 5.15.0-rc5_for_upstream_min_debug_2021_10_14_11_06 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:lockref_get+0x1/0x60
Code: 5d e9 53 ff ff ff 48 8d 7f 70 e8 0a 2e 48 00 c7 85 d0 00 00 00 02
00 00 00 c6 45 70 00 fb 5d c3 c3 cc cc cc cc cc cc cc cc 53 <48> 8b 17
48 89 fb 85 d2 75 3d 48 89 d0 bf 64 00 00 00 48 89 c1 48
RSP: 0018:ffff888137dd7a38 EFLAGS: 00010206
RAX: 0000000000000000 RBX: ffff888107d5f458 RCX: 00000000fffffffe
RDX: 000000000002c2b0 RSI: ffffffff8155e2e0 RDI: 0002000300004058
RBP: ffff888137dd7a88 R08: 0002000300004058 R09: ffff8881144a9f88
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881141d4000
R13: ffff888137dd7c68 R14: ffff888137dd7d58 R15: ffff888137dd7cc0
FS:  00007f4644f2a4c0(0000) GS:ffff8887a2d40000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b4500f4380 CR3: 0000000114f7a003 CR4: 0000000000170ea0
Call Trace:
  simple_recursive_removal+0x33/0x2e0
  ? debugfs_remove+0x60/0x60
  debugfs_remove+0x40/0x60
  mlx5_debug_cq_remove+0x32/0x70 [mlx5_core]
  mlx5_core_destroy_cq+0x41/0x1d0 [mlx5_core]
  devx_obj_cleanup+0x151/0x330 [mlx5_ib]
  ? __pollwait+0xd0/0xd0
  ? xas_load+0x5/0x70
  ? xa_load+0x62/0xa0
  destroy_hw_idr_uobject+0x20/0x80 [ib_uverbs]
  uverbs_destroy_uobject+0x3b/0x360 [ib_uverbs]
  uobj_destroy+0x54/0xa0 [ib_uverbs]
  ib_uverbs_cmd_verbs+0xaf2/0x1160 [ib_uverbs]
  ? uverbs_finalize_object+0xd0/0xd0 [ib_uverbs]
  ib_uverbs_ioctl+0xc4/0x1b0 [ib_uverbs]
  __x64_sys_ioctl+0x3e4/0x8e0

Fixes: 94b960b9 ("net/mlx5e: Fix memory leak in mlx5_core_destroy_cq() error path")
Signed-off-by: default avatarValentine Fatiev <valentinef@nvidia.com>
Reviewed-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      76ded29d
    • Paul Blakey's avatar
      net/mlx5: E-Switch, Fix resetting of encap mode when entering switchdev · d7751d64
      Paul Blakey authored 
      E-Switch encap mode is relevant only when in switchdev mode.
The RDMA driver can query the encap configuration via
mlx5_eswitch_get_encap_mode(). Make sure it returns the currently
used mode and not the set one.

This reverts the cited commit which reset the encap mode
on entering switchdev and fixes the original issue properly.

Fixes: 9a64144d ("net/mlx5: E-Switch, Fix default encap mode")
Signed-off-by: default avatarPaul Blakey <paulb@nvidia.com>
Reviewed-by: default avatarMark Bloch <mbloch@nvidia.com>
Reviewed-by: default avatarMaor Dickman <maord@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      d7751d64
    • Vlad Buslov's avatar
      net/mlx5e: Wait for concurrent flow deletion during neigh/fib events · 362980ea
      Vlad Buslov authored 
      Function mlx5e_take_tmp_flow() skips flows with zero reference count. This
can cause syndrome 0x179e84 when the called from neigh or route update code
and the skipped flow is not removed from the hardware by the time
underlying encap/decap resource is deleted. Add new completion
'del_hw_done' that is completed when flow is unoffloaded. This is safe to
do because flow with reference count zero needs to be detached from
encap/decap entry before its memory is deallocated, which requires taking
the encap_tbl_lock mutex that is held by the event handlers code.

Fixes: 8914add2 ("net/mlx5e: Handle FIB events to update tunnel endpoint device")
Signed-off-by: default avatarVlad Buslov <vladbu@nvidia.com>
Reviewed-by: default avatarRoi Dayan <roid@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      362980ea
    • Tariq Toukan's avatar
      net/mlx5e: kTLS, Fix crash in RX resync flow · cc4a9cc0
      Tariq Toukan authored 
      For the TLS RX resync flow, we maintain a list of TLS contexts
that require some attention, to communicate their resync information
to the HW.
Here we fix list corruptions, by protecting the entries against
movements coming from resync_handle_seq_match(), until their resync
handling in napi is fully completed.

Fixes: e9ce991b ("net/mlx5e: kTLS, Add resiliency to RX resync failures")
Signed-off-by: default avatarTariq Toukan <tariqt@nvidia.com>
Reviewed-by: default avatarMaxim Mikityanskiy <maximmi@nvidia.com>
Signed-off-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
      cc4a9cc0
    • David S. Miller's avatar
      Merge branch '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue · 848e5d66
      David S. Miller authored 
      Tony Nguyen says:

====================
Intel Wired LAN Driver Updates 2021-11-15

This series contains updates to iavf driver only.

Mateusz adds a wait for reset completion when changing queue count which
could otherwise cause issues with VF reset.

Nick adds a null check for vf_res in iavf_fix_features(), corrects
ordering of function calls to resolve dependency issues, and prevents
possible freeing of a lock which isn't being held.

Piotr fixes logic that did not allow setting all multicast mode without
promiscuous mode.

Jake prevents possible accidental freeing of filter structure.

Mitch adds null checks for key and indir parameters in iavf_get_rxfh().

Surabhi adds an additional check that would, previously, cause the driver
to print a false error due to values obtained while the VF is in reset.

Grzegorz prevents a queue request of 0 which would cause queue count to
reset to default values.

Akeem restores VLAN filters when bringing the interface back up.
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      848e5d66
    • Cong Wang's avatar
      udp: Validate checksum in udp_read_sock() · 099f896f
      Cong Wang authored 
      It turns out the skb's in sock receive queue could have bad checksums, as
both ->poll() and ->recvmsg() validate checksums. We have to do the same
for ->read_sock() path too before they are redirected in sockmap.

Fixes: d7f57118 ("udp: Implement ->read_sock() for sockmap")
Reported-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarCong Wang <cong.wang@bytedance.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20211115044006.26068-1-xiyou.wangcong@gmail.com
      099f896f
    • Daniel Borkmann's avatar
      bpf: Fix toctou on read-only map's constant scalar tracking · 353050be
      Daniel Borkmann authored 
      Commit a23740ec ("bpf: Track contents of read-only maps as scalars") is
checking whether maps are read-only both from BPF program side and user space
side, and then, given their content is constant, reading out their data via
map->ops->map_direct_value_addr() which is then subsequently used as known
scalar value for the register, that is, it is marked as __mark_reg_known()
with the read value at verification time. Before a23740ec, the register
content was marked as an unknown scalar so the verifier could not make any
assumptions about the map content.

The current implementation however is prone to a TOCTOU race, meaning, the
value read as known scalar for the register is not guaranteed to be exactly
the same at a later point when the program is executed, and as such, the
prior made assumptions of the verifier with regards to the program will be
invalid which can cause issues such as OOB access, etc.

While the BPF_F_RDONLY_PROG map flag is always fixed and required to be
specified at map creation time, the map->frozen property is initially set to
false for the map given the map value needs to be populated, e.g. for global
data sections. Once complete, the loader "freezes" the map from user space
such that no subsequent updates/deletes are possible anymore. For the rest
of the lifetime of the map, this freeze one-time trigger cannot be undone
anymore after a successful BPF_MAP_FREEZE cmd return. Meaning, any new BPF_*
cmd calls which would update/delete map entries will be rejected with -EPERM
since map_get_sys_perms() removes the FMODE_CAN_WRITE permission. This also
means that pending update/delete map entries must still complete before this
guarantee is given. This corner case is not an issue for loaders since they
create and prepare such program private map in successive steps.

However, a malicious user is able to trigger this TOCTOU race in two different
ways: i) via userfaultfd, and ii) via batched updates. For i) userfaultfd is
used to expand the competition interval, so that map_update_elem() can modify
the contents of the map after map_freeze() and bpf_prog_load() were executed.
This works, because userfaultfd halts the parallel thread which triggered a
map_update_elem() at the time where we copy key/value from the user buffer and
this already passed the FMODE_CAN_WRITE capability test given at that time the
map was not "frozen". Then, the main thread performs the map_freeze() and
bpf_prog_load(), and once that had completed successfully, the other thread
is woken up to complete the pending map_update_elem() which then changes the
map content. For ii) the idea of the batched update is similar, meaning, when
there are a large number of updates to be processed, it can increase the
competition interval between the two. It is therefore possible in practice to
modify the contents of the map after executing map_freeze() and bpf_prog_load().

One way to fix both i) and ii) at the same time is to expand the use of the
map's map->writecnt. The latter was introduced in fc970227 ("bpf: Add mmap()
support for BPF_MAP_TYPE_ARRAY") and further refined in 1f6cb19b ("bpf:
Prevent re-mmap()'ing BPF map as writable for initially r/o mapping") with
the rationale to make a writable mmap()'ing of a map mutually exclusive with
read-only freezing. The counter indicates writable mmap() mappings and then
prevents/fails the freeze operation. Its semantics can be expanded beyond
just mmap() by generally indicating ongoing write phases. This would essentially
span any parallel regular and batched flavor of update/delete operation and
then also have map_freeze() fail with -EBUSY. For the check_mem_access() in
the verifier we expand upon the bpf_map_is_rdonly() check ensuring that all
last pending writes have completed via bpf_map_write_active() test. Once the
map->frozen is set and bpf_map_write_active() indicates a map->writecnt of 0
only then we are really guaranteed to use the map's data as known constants.
For map->frozen being set and pending writes in process of still being completed
we fall back to marking that register as unknown scalar so we don't end up
making assumptions about it. With this, both TOCTOU reproducers from i) and
ii) are fixed.

Note that the map->writecnt has been converted into a atomic64 in the fix in
order to avoid a double freeze_mutex mutex_{un,}lock() pair when updating
map->writecnt in the various map update/delete BPF_* cmd flavors. Spanning
the freeze_mutex over entire map update/delete operations in syscall side
would not be possible due to then causing everything to be serialized.
Similarly, something like synchronize_rcu() after setting map->frozen to wait
for update/deletes to complete is not possible either since it would also
have to span the user copy which can sleep. On the libbpf side, this won't
break d66562fb ("libbpf: Add BPF object skeleton support") as the
anonymous mmap()-ed "map initialization image" is remapped as a BPF map-backed
mmap()-ed memory where for .rodata it's non-writable.

Fixes: a23740ec ("bpf: Track contents of read-only maps as scalars")
Reported-by: w1tcher.bupt@gmail.com
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
      353050be
    • Alexander Lobakin's avatar
      samples/bpf: Fix build error due to -isystem removal · 6060a6cb
      Alexander Lobakin authored 
      Since recent Kbuild updates we no longer include files from compiler
directories. However, samples/bpf/hbm_kern.h hasn't been tuned for
this (LLVM 13):

  CLANG-bpf  samples/bpf/hbm_out_kern.o
In file included from samples/bpf/hbm_out_kern.c:55:
samples/bpf/hbm_kern.h:12:10: fatal error: 'stddef.h' file not found
         ^~~~~~~~~~
1 error generated.
  CLANG-bpf  samples/bpf/hbm_edt_kern.o
In file included from samples/bpf/hbm_edt_kern.c:53:
samples/bpf/hbm_kern.h:12:10: fatal error: 'stddef.h' file not found
         ^~~~~~~~~~
1 error generated.

It is enough to just drop both stdbool.h and stddef.h from includes
to fix those.

Fixes: 04e85bbf ("isystem: delete global -isystem compile option")
Signed-off-by: default avatarAlexander Lobakin <alexandr.lobakin@intel.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: default avatarMichal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://lore.kernel.org/bpf/20211115130741.3584-1-alexandr.lobakin@intel.comSigned-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
      6060a6cb
    • Alexei Starovoitov's avatar
      Merge branch 'Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs' · 9e4dc892
      Alexei Starovoitov authored 
      Dmitrii Banshchikov says:

====================

Various locking issues are possible with bpf_ktime_get_coarse_ns() and
bpf_timer_* set of helpers.

syzbot found a locking issue with bpf_ktime_get_coarse_ns() helper executed in
BPF_PROG_TYPE_PERF_EVENT prog type - [1]. The issue is possible because the
helper uses non fast version of time accessor that isn't safe for any context.
The helper was added because it provided performance benefits in comparison to
bpf_ktime_get_ns() helper.

A similar locking issue is possible with bpf_timer_* set of helpers when used
in tracing progs.

The solution is to restrict use of the helpers in tracing progs.

In the [1] discussion it was stated that bpf_spin_lock related helpers shall
also be excluded for tracing progs. The verifier has a compatibility check
between a map and a program. If a tracing program tries to use a map which
value has struct bpf_spin_lock the verifier fails that is why bpf_spin_lock is
already restricted.

Patch 1 restricts helpers
Patch 2 adds tests

v1 -> v2:
 * Limit the helpers via func proto getters instead of allowed callback
 * Add note about helpers' restrictions to linux/bpf.h
 * Add Fixes tag
 * Remove extra \0 from btf_str_sec
 * Beside asm tests add prog tests
 * Trim CC

1. https://lore.kernel.org/all/00000000000013aebd05cff8e064@google.com/
====================
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
      9e4dc892
    • Dmitrii Banshchikov's avatar
      selftests/bpf: Add tests for restricted helpers · e60e6962
      Dmitrii Banshchikov authored 
      This patch adds tests that bpf_ktime_get_coarse_ns(), bpf_timer_* and
bpf_spin_lock()/bpf_spin_unlock() helpers are forbidden in tracing progs
as their use there may result in various locking issues.
Signed-off-by: default avatarDmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211113142227.566439-3-me@ubique.spb.ru
      e60e6962
    • Dmitrii Banshchikov's avatar
      bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs · 5e0bc308
      Dmitrii Banshchikov authored 
      Use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in tracing
progs may result in locking issues.

bpf_ktime_get_coarse_ns() uses ktime_get_coarse_ns() time accessor that
isn't safe for any context:
======================================================
WARNING: possible circular locking dependency detected
5.15.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.4/14877 is trying to acquire lock:
ffffffff8cb30008 (tk_core.seq.seqcount){----}-{0:0}, at: ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255

but task is already holding lock:
ffffffff90dbf200 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x61/0x400 lib/debugobjects.c:735

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&obj_hash[i].lock){-.-.}-{2:2}:
       lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       __debug_object_init+0xd9/0x1860 lib/debugobjects.c:569
       debug_hrtimer_init kernel/time/hrtimer.c:414 [inline]
       debug_init kernel/time/hrtimer.c:468 [inline]
       hrtimer_init+0x20/0x40 kernel/time/hrtimer.c:1592
       ntp_init_cmos_sync kernel/time/ntp.c:676 [inline]
       ntp_init+0xa1/0xad kernel/time/ntp.c:1095
       timekeeping_init+0x512/0x6bf kernel/time/timekeeping.c:1639
       start_kernel+0x267/0x56e init/main.c:1030
       secondary_startup_64_no_verify+0xb1/0xbb

-> #0 (tk_core.seq.seqcount){----}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3051 [inline]
       check_prevs_add kernel/locking/lockdep.c:3174 [inline]
       validate_chain+0x1dfb/0x8240 kernel/locking/lockdep.c:3789
       __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5015
       lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625
       seqcount_lockdep_reader_access+0xfe/0x230 include/linux/seqlock.h:103
       ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255
       ktime_get_coarse include/linux/timekeeping.h:120 [inline]
       ktime_get_coarse_ns include/linux/timekeeping.h:126 [inline]
       ____bpf_ktime_get_coarse_ns kernel/bpf/helpers.c:173 [inline]
       bpf_ktime_get_coarse_ns+0x7e/0x130 kernel/bpf/helpers.c:171
       bpf_prog_a99735ebafdda2f1+0x10/0xb50
       bpf_dispatcher_nop_func include/linux/bpf.h:721 [inline]
       __bpf_prog_run include/linux/filter.h:626 [inline]
       bpf_prog_run include/linux/filter.h:633 [inline]
       BPF_PROG_RUN_ARRAY include/linux/bpf.h:1294 [inline]
       trace_call_bpf+0x2cf/0x5d0 kernel/trace/bpf_trace.c:127
       perf_trace_run_bpf_submit+0x7b/0x1d0 kernel/events/core.c:9708
       perf_trace_lock+0x37c/0x440 include/trace/events/lock.h:39
       trace_lock_release+0x128/0x150 include/trace/events/lock.h:58
       lock_release+0x82/0x810 kernel/locking/lockdep.c:5636
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
       _raw_spin_unlock_irqrestore+0x75/0x130 kernel/locking/spinlock.c:194
       debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
       debug_deactivate kernel/time/hrtimer.c:481 [inline]
       __run_hrtimer kernel/time/hrtimer.c:1653 [inline]
       __hrtimer_run_queues+0x2f9/0xa60 kernel/time/hrtimer.c:1749
       hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811
       local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
       __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103
       sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097
       asm_sysvec_apic_timer_interrupt+0x12/0x20
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
       _raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
       try_to_wake_up+0x702/0xd20 kernel/sched/core.c:4118
       wake_up_process kernel/sched/core.c:4200 [inline]
       wake_up_q+0x9a/0xf0 kernel/sched/core.c:953
       futex_wake+0x50f/0x5b0 kernel/futex/waitwake.c:184
       do_futex+0x367/0x560 kernel/futex/syscalls.c:127
       __do_sys_futex kernel/futex/syscalls.c:199 [inline]
       __se_sys_futex+0x401/0x4b0 kernel/futex/syscalls.c:180
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

There is a possible deadlock with bpf_timer_* set of helpers:
hrtimer_start()
  lock_base();
  trace_hrtimer...()
    perf_event()
      bpf_run()
        bpf_timer_start()
          hrtimer_start()
            lock_base()         <- DEADLOCK

Forbid use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in
BPF_PROG_TYPE_KPROBE, BPF_PROG_TYPE_TRACEPOINT, BPF_PROG_TYPE_PERF_EVENT
and BPF_PROG_TYPE_RAW_TRACEPOINT prog types.

Fixes: d0551261 ("bpf: Add bpf_ktime_get_coarse_ns helper")
Fixes: b00628b1 ("bpf: Introduce bpf timers.")
Reported-by: syzbot+43fd005b5a1b4d10781e@syzkaller.appspotmail.com
Signed-off-by: default avatarDmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211113142227.566439-2-me@ubique.spb.ru
      5e0bc308
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