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Pull request for series with
subject: bpf_fib_lookup: optionally skip neighbour lookup
version: 2
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=362021

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Master branch: 1e9259e
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=362021
version: 2

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Master branch: c3f01fd
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=362021
version: 2

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Master branch: eca43ee
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=362021
version: 2

kernel-patches-bot and others added 2 commits October 9, 2020 13:13
The bpf_fib_lookup() helper performs a neighbour lookup for the destination
IP and returns BPF_FIB_LKUP_NO_NEIGH if this fails, with the expectation
that the BPF program will pass the packet up the stack in this case.
However, with the addition of bpf_redirect_neigh() that can be used instead
to perform the neighbour lookup, at the cost of a bit of duplicated work.

For that we still need the target ifindex, and since bpf_fib_lookup()
already has that at the time it performs the neighbour lookup, there is
really no reason why it can't just return it in any case. So let's just
always return the ifindex, and also add a flag that lets the caller turn
off the neighbour lookup entirely in bpf_fib_lookup().

v2:
- Add flag (Daniel)
- Remove misleading code example from commit message (David)

Cc: David Ahern <[email protected]>
Signed-off-by: Toke Høiland-Jørgensen <[email protected]>
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Master branch: ac53a0d
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=362021
version: 2

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At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=362021 irrelevant now. Closing PR.

@kernel-patches-bot kernel-patches-bot deleted the series/362021=>bpf-next branch October 16, 2020 16:25
kernel-patches-bot pushed a commit that referenced this pull request Jun 9, 2022
A static key warning splat appears during early boot on arm64 systems
that credit randomness from devicetrees that contain an "rng-seed"
property. This is because setup_machine_fdt() is called before
jump_label_init() during setup_arch(). Let's swap the order of these two
calls so that jump labels are initialized before the devicetree is
unflattened and the rng seed is credited.

 static_key_enable_cpuslocked(): static key '0xffffffe51c6fcfc0' used before call to jump_label_init()
 WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xb0/0xb8
 Modules linked in:
 CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0+ #224 44b43e377bfc84bc99bb5ab885ff694984ee09ff
 pstate: 600001c9 (nZCv dAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : static_key_enable_cpuslocked+0xb0/0xb8
 lr : static_key_enable_cpuslocked+0xb0/0xb8
 sp : ffffffe51c393cf0
 x29: ffffffe51c393cf0 x28: 000000008185054c x27: 00000000f1042f10
 x26: 0000000000000000 x25: 00000000f10302b2 x24: 0000002513200000
 x23: 0000002513200000 x22: ffffffe51c1c9000 x21: fffffffdfdc00000
 x20: ffffffe51c2f0831 x19: ffffffe51c6fcfc0 x18: 00000000ffff1020
 x17: 00000000e1e2ac90 x16: 00000000000000e0 x15: ffffffe51b710708
 x14: 0000000000000066 x13: 0000000000000018 x12: 0000000000000000
 x11: 0000000000000000 x10: 00000000ffffffff x9 : 0000000000000000
 x8 : 0000000000000000 x7 : 61632065726f6665 x6 : 6220646573752027
 x5 : ffffffe51c641d25 x4 : ffffffe51c13142c x3 : ffff0a00ffffff05
 x2 : 40000000ffffe003 x1 : 00000000000001c0 x0 : 0000000000000065
 Call trace:
  static_key_enable_cpuslocked+0xb0/0xb8
  static_key_enable+0x2c/0x40
  crng_set_ready+0x24/0x30
  execute_in_process_context+0x80/0x90
  _credit_init_bits+0x100/0x154
  add_bootloader_randomness+0x64/0x78
  early_init_dt_scan_chosen+0x140/0x184
  early_init_dt_scan_nodes+0x28/0x4c
  early_init_dt_scan+0x40/0x44
  setup_machine_fdt+0x7c/0x120
  setup_arch+0x74/0x1d8
  start_kernel+0x84/0x44c
  __primary_switched+0xc0/0xc8
 ---[ end trace 0000000000000000 ]---
 random: crng init done
 Machine model: Google Lazor (rev1 - 2) with LTE

Cc: Hsin-Yi Wang <[email protected]>
Cc: Douglas Anderson <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Jason A. Donenfeld <[email protected]>
Cc: Dominik Brodowski <[email protected]>
Fixes: f5bda35 ("random: use static branch for crng_ready()")
Signed-off-by: Stephen Boyd <[email protected]>
Reviewed-by: Jason A. Donenfeld <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Catalin Marinas <[email protected]>
kernel-patches-bot pushed a commit that referenced this pull request Jun 18, 2022
Stephen reported that a static key warning splat appears during early
boot on systems that credit randomness from device trees that contain an
"rng-seed" property, because because setup_machine_fdt() is called
before jump_label_init() during setup_arch():

 static_key_enable_cpuslocked(): static key '0xffffffe51c6fcfc0' used before call to jump_label_init()
 WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xb0/0xb8
 Modules linked in:
 CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0+ #224 44b43e377bfc84bc99bb5ab885ff694984ee09ff
 pstate: 600001c9 (nZCv dAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : static_key_enable_cpuslocked+0xb0/0xb8
 lr : static_key_enable_cpuslocked+0xb0/0xb8
 sp : ffffffe51c393cf0
 x29: ffffffe51c393cf0 x28: 000000008185054c x27: 00000000f1042f10
 x26: 0000000000000000 x25: 00000000f10302b2 x24: 0000002513200000
 x23: 0000002513200000 x22: ffffffe51c1c9000 x21: fffffffdfdc00000
 x20: ffffffe51c2f0831 x19: ffffffe51c6fcfc0 x18: 00000000ffff1020
 x17: 00000000e1e2ac90 x16: 00000000000000e0 x15: ffffffe51b710708
 x14: 0000000000000066 x13: 0000000000000018 x12: 0000000000000000
 x11: 0000000000000000 x10: 00000000ffffffff x9 : 0000000000000000
 x8 : 0000000000000000 x7 : 61632065726f6665 x6 : 6220646573752027
 x5 : ffffffe51c641d25 x4 : ffffffe51c13142c x3 : ffff0a00ffffff05
 x2 : 40000000ffffe003 x1 : 00000000000001c0 x0 : 0000000000000065
 Call trace:
  static_key_enable_cpuslocked+0xb0/0xb8
  static_key_enable+0x2c/0x40
  crng_set_ready+0x24/0x30
  execute_in_process_context+0x80/0x90
  _credit_init_bits+0x100/0x154
  add_bootloader_randomness+0x64/0x78
  early_init_dt_scan_chosen+0x140/0x184
  early_init_dt_scan_nodes+0x28/0x4c
  early_init_dt_scan+0x40/0x44
  setup_machine_fdt+0x7c/0x120
  setup_arch+0x74/0x1d8
  start_kernel+0x84/0x44c
  __primary_switched+0xc0/0xc8
 ---[ end trace 0000000000000000 ]---
 random: crng init done
 Machine model: Google Lazor (rev1 - 2) with LTE

A trivial fix went in to address this on arm64, 73e2d82 ("arm64:
Initialize jump labels before setup_machine_fdt()"). I wrote patches as
well for arm32 and risc-v. But still patches are needed on xtensa,
powerpc, arc, and mips. So that's 7 platforms where things aren't quite
right. This sort of points to larger issues that might need a larger
solution.

Instead, this commit just defers setting the static branch until later
in the boot process. random_init() is called after jump_label_init() has
been called, and so is always a safe place from which to adjust the
static branch.

Fixes: f5bda35 ("random: use static branch for crng_ready()")
Reported-by: Stephen Boyd <[email protected]>
Reported-by: Phil Elwell <[email protected]>
Tested-by: Phil Elwell <[email protected]>
Reviewed-by: Ard Biesheuvel <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Russell King <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Signed-off-by: Jason A. Donenfeld <[email protected]>
kernel-patches-bot pushed a commit that referenced this pull request Jul 23, 2022
Use after free is detected by kfence when disabling sriov. What was read
after being freed was vf->pci_dev: it was freed from pci_disable_sriov
and later read in efx_ef10_sriov_free_vf_vports, called from
efx_ef10_sriov_free_vf_vswitching.

Set the pointer to NULL at release time to not trying to read it later.

Reproducer and dmesg log (note that kfence doesn't detect it every time):
$ echo 1 > /sys/class/net/enp65s0f0np0/device/sriov_numvfs
$ echo 0 > /sys/class/net/enp65s0f0np0/device/sriov_numvfs

 BUG: KFENCE: use-after-free read in efx_ef10_sriov_free_vf_vswitching+0x82/0x170 [sfc]

 Use-after-free read at 0x00000000ff3c1ba5 (in kfence-#224):
  efx_ef10_sriov_free_vf_vswitching+0x82/0x170 [sfc]
  efx_ef10_pci_sriov_disable+0x38/0x70 [sfc]
  efx_pci_sriov_configure+0x24/0x40 [sfc]
  sriov_numvfs_store+0xfe/0x140
  kernfs_fop_write_iter+0x11c/0x1b0
  new_sync_write+0x11f/0x1b0
  vfs_write+0x1eb/0x280
  ksys_write+0x5f/0xe0
  do_syscall_64+0x5c/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xae

 kfence-#224: 0x00000000edb8ef95-0x00000000671f5ce1, size=2792, cache=kmalloc-4k

 allocated by task 6771 on cpu 10 at 3137.860196s:
  pci_alloc_dev+0x21/0x60
  pci_iov_add_virtfn+0x2a2/0x320
  sriov_enable+0x212/0x3e0
  efx_ef10_sriov_configure+0x67/0x80 [sfc]
  efx_pci_sriov_configure+0x24/0x40 [sfc]
  sriov_numvfs_store+0xba/0x140
  kernfs_fop_write_iter+0x11c/0x1b0
  new_sync_write+0x11f/0x1b0
  vfs_write+0x1eb/0x280
  ksys_write+0x5f/0xe0
  do_syscall_64+0x5c/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xae

 freed by task 6771 on cpu 12 at 3170.991309s:
  device_release+0x34/0x90
  kobject_cleanup+0x3a/0x130
  pci_iov_remove_virtfn+0xd9/0x120
  sriov_disable+0x30/0xe0
  efx_ef10_pci_sriov_disable+0x57/0x70 [sfc]
  efx_pci_sriov_configure+0x24/0x40 [sfc]
  sriov_numvfs_store+0xfe/0x140
  kernfs_fop_write_iter+0x11c/0x1b0
  new_sync_write+0x11f/0x1b0
  vfs_write+0x1eb/0x280
  ksys_write+0x5f/0xe0
  do_syscall_64+0x5c/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: 3c5eb87 ("sfc: create vports for VFs and assign random MAC addresses")
Reported-by: Yanghang Liu <[email protected]>
Signed-off-by: Íñigo Huguet <[email protected]>
Acked-by: Martin Habets <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
borkmann added a commit to cilium/kernel-bpf-ci that referenced this pull request Jun 7, 2023
Add a big batch of test coverage to assert all aspects of the tcx link API:

  # ./vmtest.sh -- ./test_progs -t tc_links
  [...]
  kernel-patches#224     tc_links_after:OK
  kernel-patches#225     tc_links_append:OK
  kernel-patches#226     tc_links_basic:OK
  kernel-patches#227     tc_links_before:OK
  kernel-patches#228     tc_links_both:OK
  kernel-patches#229     tc_links_chain_classic:OK
  kernel-patches#230     tc_links_dev_cleanup:OK
  kernel-patches#231     tc_links_first:OK
  kernel-patches#232     tc_links_invalid:OK
  kernel-patches#233     tc_links_last:OK
  kernel-patches#234     tc_links_prepend:OK
  kernel-patches#235     tc_links_replace:OK
  kernel-patches#236     tc_links_revision:OK
  Summary: 13/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <[email protected]>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Jun 7, 2023
Add a big batch of test coverage to assert all aspects of the tcx link API:

  # ./vmtest.sh -- ./test_progs -t tc_links
  [...]
  #224     tc_links_after:OK
  #225     tc_links_append:OK
  #226     tc_links_basic:OK
  #227     tc_links_before:OK
  #228     tc_links_both:OK
  #229     tc_links_chain_classic:OK
  #230     tc_links_dev_cleanup:OK
  #231     tc_links_first:OK
  #232     tc_links_invalid:OK
  #233     tc_links_last:OK
  #234     tc_links_prepend:OK
  #235     tc_links_replace:OK
  #236     tc_links_revision:OK
  Summary: 13/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <[email protected]>
yurinnick pushed a commit to yurinnick/kernel-patches-bpf that referenced this pull request Jun 7, 2023
Add a big batch of test coverage to assert all aspects of the tcx link API:

  # ./vmtest.sh -- ./test_progs -t tc_links
  [...]
  kernel-patches#224     tc_links_after:OK
  kernel-patches#225     tc_links_append:OK
  kernel-patches#226     tc_links_basic:OK
  kernel-patches#227     tc_links_before:OK
  kernel-patches#228     tc_links_both:OK
  kernel-patches#229     tc_links_chain_classic:OK
  kernel-patches#230     tc_links_dev_cleanup:OK
  kernel-patches#231     tc_links_first:OK
  kernel-patches#232     tc_links_invalid:OK
  kernel-patches#233     tc_links_last:OK
  kernel-patches#234     tc_links_prepend:OK
  kernel-patches#235     tc_links_replace:OK
  kernel-patches#236     tc_links_revision:OK
  Summary: 13/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <[email protected]>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Jun 8, 2023
Add a big batch of test coverage to assert all aspects of the tcx link API:

  # ./vmtest.sh -- ./test_progs -t tc_links
  [...]
  #224     tc_links_after:OK
  #225     tc_links_append:OK
  #226     tc_links_basic:OK
  #227     tc_links_before:OK
  #228     tc_links_both:OK
  #229     tc_links_chain_classic:OK
  #230     tc_links_dev_cleanup:OK
  #231     tc_links_first:OK
  #232     tc_links_invalid:OK
  #233     tc_links_last:OK
  #234     tc_links_prepend:OK
  #235     tc_links_replace:OK
  #236     tc_links_revision:OK
  Summary: 13/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <[email protected]>
yurinnick pushed a commit to yurinnick/kernel-patches-bpf that referenced this pull request Jun 8, 2023
Add a big batch of test coverage to assert all aspects of the tcx link API:

  # ./vmtest.sh -- ./test_progs -t tc_links
  [...]
  kernel-patches#224     tc_links_after:OK
  kernel-patches#225     tc_links_append:OK
  kernel-patches#226     tc_links_basic:OK
  kernel-patches#227     tc_links_before:OK
  kernel-patches#228     tc_links_both:OK
  kernel-patches#229     tc_links_chain_classic:OK
  kernel-patches#230     tc_links_dev_cleanup:OK
  kernel-patches#231     tc_links_first:OK
  kernel-patches#232     tc_links_invalid:OK
  kernel-patches#233     tc_links_last:OK
  kernel-patches#234     tc_links_prepend:OK
  kernel-patches#235     tc_links_replace:OK
  kernel-patches#236     tc_links_revision:OK
  Summary: 13/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <[email protected]>
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