Skip to content

bpf: Pointers beyond packet end. #334

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 4 commits into from

Conversation

kernel-patches-bot
Copy link

Pull request for series with
subject: bpf: Pointers beyond packet end.
version: 2
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=381673

@kernel-patches-bot
Copy link
Author

Master branch: 9600d62
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=381673
version: 2

@kernel-patches-bot
Copy link
Author

Master branch: 7112d12
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=381673
version: 2

kernel-patches-bot and others added 4 commits November 12, 2020 14:32
This patch adds the verifier support to recognize inlined branch conditions.
The LLVM knows that the branch evaluates to the same value, but the verifier
couldn't track it. Hence causing valid programs to be rejected.
The potential LLVM workaround: https://reviews.llvm.org/D87428
can have undesired side effects, since LLVM doesn't know that
skb->data/data_end are being compared. LLVM has to introduce extra boolean
variable and use inline_asm trick to force easier for the verifier assembly.

Instead teach the verifier to recognize that
r1 = skb->data;
r1 += 10;
r2 = skb->data_end;
if (r1 > r2) {
  here r1 points beyond packet_end and
  subsequent
  if (r1 > r2) // always evaluates to "true".
}

Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Add a test that currently makes LLVM generate assembly code:

$ llvm-objdump -S skb_pkt_end.o
0000000000000000 <main_prog>:
; 	if (skb_shorter(skb, ETH_IPV4_TCP_SIZE))
       0:	61 12 50 00 00 00 00 00	r2 = *(u32 *)(r1 + 80)
       1:	61 14 4c 00 00 00 00 00	r4 = *(u32 *)(r1 + 76)
       2:	bf 43 00 00 00 00 00 00	r3 = r4
       3:	07 03 00 00 36 00 00 00	r3 += 54
       4:	b7 01 00 00 00 00 00 00	r1 = 0
       5:	2d 23 02 00 00 00 00 00	if r3 > r2 goto +2 <LBB0_2>
       6:	07 04 00 00 0e 00 00 00	r4 += 14
; 	if (skb_shorter(skb, ETH_IPV4_TCP_SIZE))
       7:	bf 41 00 00 00 00 00 00	r1 = r4
0000000000000040 <LBB0_2>:
       8:	b4 00 00 00 ff ff ff ff	w0 = -1
; 	if (!(ip = get_iphdr(skb)))
       9:	2d 23 05 00 00 00 00 00	if r3 > r2 goto +5 <LBB0_6>
; 	proto = ip->protocol;
      10:	71 12 09 00 00 00 00 00	r2 = *(u8 *)(r1 + 9)
; 	if (proto != IPPROTO_TCP)
      11:	56 02 03 00 06 00 00 00	if w2 != 6 goto +3 <LBB0_6>
; 	if (tcp->dest != 0)
      12:	69 12 16 00 00 00 00 00	r2 = *(u16 *)(r1 + 22)
      13:	56 02 01 00 00 00 00 00	if w2 != 0 goto +1 <LBB0_6>
; 	return tcp->urg_ptr;
      14:	69 10 26 00 00 00 00 00	r0 = *(u16 *)(r1 + 38)
0000000000000078 <LBB0_6>:
; }
      15:	95 00 00 00 00 00 00 00	exit

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Add few assembly tests for packet comparison.

Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
@kernel-patches-bot
Copy link
Author

Master branch: c365387
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=381673
version: 2

@kernel-patches-bot
Copy link
Author

At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=381673 irrelevant now. Closing PR.

@kernel-patches-bot kernel-patches-bot deleted the series/368349=>bpf-next branch November 13, 2020 00:57
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Jul 8, 2024
Add a test case which replaces an active ingress qdisc while keeping the
miniq in-tact during the transition period to the new clsact qdisc.

  # ./vmtest.sh -- ./test_progs -t tc_link
  [...]
  ./test_progs -t tc_link
  [    3.412871] bpf_testmod: loading out-of-tree module taints kernel.
  [    3.413343] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  #332     tc_links_after:OK
  #333     tc_links_append:OK
  #334     tc_links_basic:OK
  #335     tc_links_before:OK
  #336     tc_links_chain_classic:OK
  #337     tc_links_chain_mixed:OK
  #338     tc_links_dev_chain0:OK
  #339     tc_links_dev_cleanup:OK
  #340     tc_links_dev_mixed:OK
  #341     tc_links_ingress:OK
  #342     tc_links_invalid:OK
  #343     tc_links_prepend:OK
  #344     tc_links_replace:OK
  #345     tc_links_revision:OK
  Summary: 14/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <martin.lau@kernel.org>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Jul 8, 2024
Add a test case which replaces an active ingress qdisc while keeping the
miniq in-tact during the transition period to the new clsact qdisc.

  # ./vmtest.sh -- ./test_progs -t tc_link
  [...]
  ./test_progs -t tc_link
  [    3.412871] bpf_testmod: loading out-of-tree module taints kernel.
  [    3.413343] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  #332     tc_links_after:OK
  #333     tc_links_append:OK
  #334     tc_links_basic:OK
  #335     tc_links_before:OK
  #336     tc_links_chain_classic:OK
  #337     tc_links_chain_mixed:OK
  #338     tc_links_dev_chain0:OK
  #339     tc_links_dev_cleanup:OK
  #340     tc_links_dev_mixed:OK
  #341     tc_links_ingress:OK
  #342     tc_links_invalid:OK
  #343     tc_links_prepend:OK
  #344     tc_links_replace:OK
  #345     tc_links_revision:OK
  Summary: 14/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <martin.lau@kernel.org>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Jul 8, 2024
Add a test case which replaces an active ingress qdisc while keeping the
miniq in-tact during the transition period to the new clsact qdisc.

  # ./vmtest.sh -- ./test_progs -t tc_link
  [...]
  ./test_progs -t tc_link
  [    3.412871] bpf_testmod: loading out-of-tree module taints kernel.
  [    3.413343] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  #332     tc_links_after:OK
  #333     tc_links_append:OK
  #334     tc_links_basic:OK
  #335     tc_links_before:OK
  #336     tc_links_chain_classic:OK
  #337     tc_links_chain_mixed:OK
  #338     tc_links_dev_chain0:OK
  #339     tc_links_dev_cleanup:OK
  #340     tc_links_dev_mixed:OK
  #341     tc_links_ingress:OK
  #342     tc_links_invalid:OK
  #343     tc_links_prepend:OK
  #344     tc_links_replace:OK
  #345     tc_links_revision:OK
  Summary: 14/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240708133130.11609-2-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
anakryiko pushed a commit to anakryiko/bpf-ci that referenced this pull request Oct 21, 2024
Currently, there is no terminator entry for exynosautov920_cmu_of_match,
hence facing below KASAN warning,

	BUG: KASAN: global-out-of-bounds in of_match_node+0x120/0x13c
	Read of size 1 at addr ffffffe31cc9e628 by task swapper/0/1

	CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.11.0+ kernel-patches#334
	Hardware name: linux,dummy-virt (DT)
	Call trace:
	 dump_backtrace+0x94/0xec
	 show_stack+0x18/0x24
	 dump_stack_lvl+0x90/0xd0
	 print_report+0x1f4/0x5b4
	 kasan_report+0xc8/0x110
	 __asan_report_load1_noabort+0x20/0x2c
	 of_match_node+0x120/0x13c
	 of_match_device+0x70/0xb4
	 platform_match+0xa0/0x25c
	 __device_attach_driver+0x7c/0x2d4
	 bus_for_each_drv+0x100/0x188
	 __device_attach+0x174/0x364
	 device_initial_probe+0x14/0x20
	 bus_probe_device+0x128/0x158
	 device_add+0xb3c/0x10fc
	 of_device_add+0xdc/0x150
	 of_platform_device_create_pdata+0x120/0x20c
	 of_platform_bus_create+0x2bc/0x620
	 of_platform_populate+0x58/0x108
	 of_platform_default_populate_init+0x100/0x120
	 do_one_initcall+0x110/0x788
	 kernel_init_freeable+0x44c/0x61c
	 kernel_init+0x24/0x1e4
	 ret_from_fork+0x10/0x20

	The buggy address belongs to the variable:
	 exynosautov920_cmu_of_match+0xc8/0x2c80

Add a dummy terminator entry at the end to assist of_match_node() in
traversing up to the terminator entry without accessing an
out-of-boundary index.

Fixes: 485e13f ("clk: samsung: add top clock support for ExynosAuto v920 SoC")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20240927102104.3268790-1-ruanjinjie@huawei.com
[krzk: drop trailing comma]
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
Development

Successfully merging this pull request may close these issues.

1 participant