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Pull request for series with
subject: selftests: netfilter: add cpu counter check
version: 1
url: https://patchwork.kernel.org/project/bpf/list/?series=360561

kernel-patches-bot and others added 5 commits October 6, 2020 17:16
run task on first CPU with netfilter counters reset and check
cpu meta after another ping

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When some test directly done with check_one_counter() fails,
counter variable is undefined. This patch calls ip with cname
which avoids errors like:
FAIL: oskuidcounter, want "packets 2", got
Error: syntax error, unexpected newline, expecting string
list counter inet filter
                        ^
Error is now correctly rendered:
FAIL: oskuidcounter, want "packets 2", got
table inet filter {
	counter oskuidcounter {
		packets 1 bytes 84
	}
}

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
cnt was not used in nft_meta.sh
This patch also fixes 2 shellcheck SC2181 warnings:
"check exit code directly with e.g. 'if mycmd;', not indirectly with
$?."

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Check packets are correctly placed in current year.
Also do a NULL check for another one.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
@kernel-patches-bot
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Master branch: d82a532
series: https://patchwork.kernel.org/project/bpf/list/?series=360561
version: 1

@kernel-patches-bot kernel-patches-bot deleted the series/360561=>bpf branch October 7, 2020 01:46
kernel-patches-bot pushed a commit that referenced this pull request Nov 12, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 12, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 12, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 12, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 12, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 15, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 15, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 16, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 16, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 16, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 16, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-bot pushed a commit that referenced this pull request Nov 16, 2021
This patch adds '--timing' to test_progs. It tracks and print timing
information for each tests, it also prints top 10 slowest tests in the
summary.

Example output:
  $./test_progs --timing -j
  #1 align:OK (16 ms)
  ...
  #203 xdp_bonding:OK (2019 ms)
  #206 xdp_cpumap_attach:OK (3 ms)
  #207 xdp_devmap_attach:OK (4 ms)
  #208 xdp_info:OK (4 ms)
  #209 xdp_link:OK (4 ms)

  Top 10 Slowest tests:
  #48 fexit_stress: 34356 ms
  #160 test_lsm: 29602 ms
  #161 test_overhead: 29190 ms
  #159 test_local_storage: 28959 ms
  #158 test_ima: 28521 ms
  #185 verif_scale_pyperf600: 19524 ms
  #199 vmlinux: 17310 ms
  #154 tc_redirect: 11491 ms (serial)
  #147 task_local_storage: 7612 ms
  #183 verif_scale_pyperf180: 7186 ms
  Summary: 212/973 PASSED, 3 SKIPPED, 0 FAILED

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Apr 11, 2023
UBSAN: shift-out-of-bounds in net/ipv4/tcp_input.c:555:23
shift exponent 255 is too large for 32-bit type 'int'
CPU: 1 PID: 7907 Comm: ssh Not tainted 6.3.0-rc4-00161-g62bad54b26db-dirty #206
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x136/0x150
 __ubsan_handle_shift_out_of_bounds+0x21f/0x5a0
 tcp_init_transfer.cold+0x3a/0xb9
 tcp_finish_connect+0x1d0/0x620
 tcp_rcv_state_process+0xd78/0x4d60
 tcp_v4_do_rcv+0x33d/0x9d0
 __release_sock+0x133/0x3b0
 release_sock+0x58/0x1b0

'maxwin' is int, shifting int for 32 or more bits is undefined behaviour.

Fixes: 1da177e ("Linux-2.6.12-rc2")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
kuba-moo pushed a commit to linux-netdev/testing-bpf-ci that referenced this pull request Jan 10, 2025
[BUG]
Syzbot reported a crash with the following call trace:

  BTRFS info (device loop0): scrub: started on devid 1
  BUG: kernel NULL pointer dereference, address: 0000000000000208
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0
  Oops: Oops: 0000 [kernel-patches#1] PREEMPT SMP NOPTI
  CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G           O       6.13.0-rc4-custom+ kernel-patches#206
  Tainted: [O]=OOT_MODULE
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
  RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs]
  Call Trace:
   <TASK>
   scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs]
   scrub_simple_mirror+0x175/0x260 [btrfs]
   scrub_stripe+0x5d4/0x6c0 [btrfs]
   scrub_chunk+0xbb/0x170 [btrfs]
   scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs]
   btrfs_scrub_dev+0x240/0x600 [btrfs]
   btrfs_ioctl+0x1dc8/0x2fa0 [btrfs]
   ? do_sys_openat2+0xa5/0xf0
   __x64_sys_ioctl+0x97/0xc0
   do_syscall_64+0x4f/0x120
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
   </TASK>

[CAUSE]
The reproducer is using a corrupted image where extent tree root is
corrupted, thus forcing to use "rescue=all,ro" mount option to mount the
image.

Then it triggered a scrub, but since scrub relies on extent tree to find
where the data/metadata extents are, scrub_find_fill_first_stripe()
relies on an non-empty extent root.

But unfortunately scrub_find_fill_first_stripe() doesn't really expect
an NULL pointer for extent root, it use extent_root to grab fs_info and
triggered a NULL pointer dereference.

[FIX]
Add an extra check for a valid extent root at the beginning of
scrub_find_fill_first_stripe().

The new error path is introduced by 42437a6 ("btrfs: introduce
mount option rescue=ignorebadroots"), but that's pretty old, and later
commit b979547 ("btrfs: scrub: introduce helper to find and fill
sector info for a scrub_stripe") changed how we do scrub.

So for kernels older than 6.6, the fix will need manual backport.

Reported-by: syzbot+339e9dbe3a2ca419b85d@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/67756935.050a0220.25abdd.0a12.GAE@google.com/
Fixes: 42437a6 ("btrfs: introduce mount option rescue=ignorebadroots")
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Feb 1, 2025
Yan Zhai reported a BPF prog could trigger a null-ptr-deref [0]
in trace_kfree_skb if the prog does not check if rx_sk is NULL.

Commit c53795d ("net: add rx_sk to trace_kfree_skb") added
rx_sk to trace_kfree_skb, but rx_sk is optional and could be NULL.

Let's add __nullable suffix to rx_sk to let the BPF verifier
validate such a prog and prevent the issue.

Now we fail to load such a prog:

  libbpf: prog 'drop': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0
  ; int BPF_PROG(drop, struct sk_buff *skb, void *location, @ kfree_skb_sk_null.bpf.c:21
  0: (79) r3 = *(u64 *)(r1 +24)
  func 'kfree_skb' arg3 has btf_id 5253 type STRUCT 'sock'
  1: R1=ctx() R3_w=trusted_ptr_or_null_sock(id=1)
  ; bpf_printk("sk: %d, %d\n", sk, sk->__sk_common.skc_family); @ kfree_skb_sk_null.bpf.c:24
  1: (69) r4 = *(u16 *)(r3 +16)
  R3 invalid mem access 'trusted_ptr_or_null_'
  processed 2 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --

Note this fix requires commit 8aeaed2 ("bpf: Support
__nullable argument suffix for tp_btf").

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000010
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP
CPU: 6 UID: 0 PID: 348 Comm: sshd Not tainted 6.12.11 #206
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 0f 1f 00 55 48 89 e5 48 8b 57 18 <48> 0f b7 4a 10 48 bf 0c 4f e2 c1 ad 90 ff ff be 0c 00 00 00 e8 0f
RSP: 0018:ffffa86640b53da8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffa866402d1000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffa866402d1048 RDI: ffffa86640b53dc8
RBP: ffffa86640b53da8 R08: 0000000000000000 R09: 9c908cd09b9c8c91
R10: ffff90adc056b540 R11: 0000000000000002 R12: 0000000000000000
R13: ffffa86640b53e88 R14: 0000000000000800 R15: fffffffffffffffe
FS:  00007f2a27c2b480(0000) GS:ffff90b0efd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000100e69004 CR4: 00000000001726f0
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x148/0x420
 ? search_bpf_extables+0x5b/0x70
 ? fixup_exception+0x27/0x2c0
 ? exc_page_fault+0x75/0x170
 ? asm_exc_page_fault+0x22/0x30
 ? bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
 bpf_trace_run4+0x68/0xd0
 ? unix_stream_connect+0x1f4/0x6f0
 sk_skb_reason_drop+0x90/0x120
 unix_stream_connect+0x1f4/0x6f0
 __sys_connect+0x7f/0xb0
 __x64_sys_connect+0x14/0x20
 do_syscall_64+0x47/0xc30
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f2a27f296a0
Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 41 ff 0c 00 00 74 17 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 54
RSP: 002b:00007ffe29274f58 EFLAGS: 00000202 ORIG_RAX: 000000000000002a

Fixes: c53795d ("net: add rx_sk to trace_kfree_skb")
Reported-by: Yan Zhai <yan@cloudflare.com>
Closes: https://lore.kernel.org/netdev/Z50zebTRzI962e6X@debian.debian/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Feb 1, 2025
Yan Zhai reported a BPF prog could trigger a null-ptr-deref [0]
in trace_kfree_skb if the prog does not check if rx_sk is NULL.

Commit c53795d ("net: add rx_sk to trace_kfree_skb") added
rx_sk to trace_kfree_skb, but rx_sk is optional and could be NULL.

Let's add __nullable suffix to rx_sk to let the BPF verifier
validate such a prog and prevent the issue.

Now we fail to load such a prog:

  libbpf: prog 'drop': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0
  ; int BPF_PROG(drop, struct sk_buff *skb, void *location, @ kfree_skb_sk_null.bpf.c:21
  0: (79) r3 = *(u64 *)(r1 +24)
  func 'kfree_skb' arg3 has btf_id 5253 type STRUCT 'sock'
  1: R1=ctx() R3_w=trusted_ptr_or_null_sock(id=1)
  ; bpf_printk("sk: %d, %d\n", sk, sk->__sk_common.skc_family); @ kfree_skb_sk_null.bpf.c:24
  1: (69) r4 = *(u16 *)(r3 +16)
  R3 invalid mem access 'trusted_ptr_or_null_'
  processed 2 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --

Note this fix requires commit 8aeaed2 ("bpf: Support
__nullable argument suffix for tp_btf").

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000010
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP
CPU: 6 UID: 0 PID: 348 Comm: sshd Not tainted 6.12.11 #206
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 0f 1f 00 55 48 89 e5 48 8b 57 18 <48> 0f b7 4a 10 48 bf 0c 4f e2 c1 ad 90 ff ff be 0c 00 00 00 e8 0f
RSP: 0018:ffffa86640b53da8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffa866402d1000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffa866402d1048 RDI: ffffa86640b53dc8
RBP: ffffa86640b53da8 R08: 0000000000000000 R09: 9c908cd09b9c8c91
R10: ffff90adc056b540 R11: 0000000000000002 R12: 0000000000000000
R13: ffffa86640b53e88 R14: 0000000000000800 R15: fffffffffffffffe
FS:  00007f2a27c2b480(0000) GS:ffff90b0efd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000100e69004 CR4: 00000000001726f0
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x148/0x420
 ? search_bpf_extables+0x5b/0x70
 ? fixup_exception+0x27/0x2c0
 ? exc_page_fault+0x75/0x170
 ? asm_exc_page_fault+0x22/0x30
 ? bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
 bpf_trace_run4+0x68/0xd0
 ? unix_stream_connect+0x1f4/0x6f0
 sk_skb_reason_drop+0x90/0x120
 unix_stream_connect+0x1f4/0x6f0
 __sys_connect+0x7f/0xb0
 __x64_sys_connect+0x14/0x20
 do_syscall_64+0x47/0xc30
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f2a27f296a0
Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 41 ff 0c 00 00 74 17 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 54
RSP: 002b:00007ffe29274f58 EFLAGS: 00000202 ORIG_RAX: 000000000000002a

Fixes: c53795d ("net: add rx_sk to trace_kfree_skb")
Reported-by: Yan Zhai <yan@cloudflare.com>
Closes: https://lore.kernel.org/netdev/Z50zebTRzI962e6X@debian.debian/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Yan Zhai <yan@cloudflare.com>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Feb 1, 2025
Yan Zhai reported a BPF prog could trigger a null-ptr-deref [0]
in trace_kfree_skb if the prog does not check if rx_sk is NULL.

Commit c53795d ("net: add rx_sk to trace_kfree_skb") added
rx_sk to trace_kfree_skb, but rx_sk is optional and could be NULL.

Let's add kfree_skb to raw_tp_null_args[] to let the BPF verifier
validate such a prog and prevent the issue.

Now we fail to load such a prog:

  libbpf: prog 'drop': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0
  ; int BPF_PROG(drop, struct sk_buff *skb, void *location, @ kfree_skb_sk_null.bpf.c:21
  0: (79) r3 = *(u64 *)(r1 +24)
  func 'kfree_skb' arg3 has btf_id 5253 type STRUCT 'sock'
  1: R1=ctx() R3_w=trusted_ptr_or_null_sock(id=1)
  ; bpf_printk("sk: %d, %d\n", sk, sk->__sk_common.skc_family); @ kfree_skb_sk_null.bpf.c:24
  1: (69) r4 = *(u16 *)(r3 +16)
  R3 invalid mem access 'trusted_ptr_or_null_'
  processed 2 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --

Note this fix requires commit 838a10b ("bpf: Augment raw_tp
arguments with PTR_MAYBE_NULL").

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000010
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP
CPU: 6 UID: 0 PID: 348 Comm: sshd Not tainted 6.12.11 #206
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 0f 1f 00 55 48 89 e5 48 8b 57 18 <48> 0f b7 4a 10 48 bf 0c 4f e2 c1 ad 90 ff ff be 0c 00 00 00 e8 0f
RSP: 0018:ffffa86640b53da8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffa866402d1000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffa866402d1048 RDI: ffffa86640b53dc8
RBP: ffffa86640b53da8 R08: 0000000000000000 R09: 9c908cd09b9c8c91
R10: ffff90adc056b540 R11: 0000000000000002 R12: 0000000000000000
R13: ffffa86640b53e88 R14: 0000000000000800 R15: fffffffffffffffe
FS:  00007f2a27c2b480(0000) GS:ffff90b0efd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000100e69004 CR4: 00000000001726f0
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x148/0x420
 ? search_bpf_extables+0x5b/0x70
 ? fixup_exception+0x27/0x2c0
 ? exc_page_fault+0x75/0x170
 ? asm_exc_page_fault+0x22/0x30
 ? bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
 bpf_trace_run4+0x68/0xd0
 ? unix_stream_connect+0x1f4/0x6f0
 sk_skb_reason_drop+0x90/0x120
 unix_stream_connect+0x1f4/0x6f0
 __sys_connect+0x7f/0xb0
 __x64_sys_connect+0x14/0x20
 do_syscall_64+0x47/0xc30
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f2a27f296a0
Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 41 ff 0c 00 00 74 17 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 54
RSP: 002b:00007ffe29274f58 EFLAGS: 00000202 ORIG_RAX: 000000000000002a

Fixes: c53795d ("net: add rx_sk to trace_kfree_skb")
Reported-by: Yan Zhai <yan@cloudflare.com>
Closes: https://lore.kernel.org/netdev/Z50zebTRzI962e6X@debian.debian/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Feb 1, 2025
Yan Zhai reported a BPF prog could trigger a null-ptr-deref [0]
in trace_kfree_skb if the prog does not check if rx_sk is NULL.

Commit c53795d ("net: add rx_sk to trace_kfree_skb") added
rx_sk to trace_kfree_skb, but rx_sk is optional and could be NULL.

Let's add kfree_skb to raw_tp_null_args[] to let the BPF verifier
validate such a prog and prevent the issue.

Now we fail to load such a prog:

  libbpf: prog 'drop': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0
  ; int BPF_PROG(drop, struct sk_buff *skb, void *location, @ kfree_skb_sk_null.bpf.c:21
  0: (79) r3 = *(u64 *)(r1 +24)
  func 'kfree_skb' arg3 has btf_id 5253 type STRUCT 'sock'
  1: R1=ctx() R3_w=trusted_ptr_or_null_sock(id=1)
  ; bpf_printk("sk: %d, %d\n", sk, sk->__sk_common.skc_family); @ kfree_skb_sk_null.bpf.c:24
  1: (69) r4 = *(u16 *)(r3 +16)
  R3 invalid mem access 'trusted_ptr_or_null_'
  processed 2 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --

Note this fix requires commit 838a10b ("bpf: Augment raw_tp
arguments with PTR_MAYBE_NULL").

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000010
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP
CPU: 6 UID: 0 PID: 348 Comm: sshd Not tainted 6.12.11 #206
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 0f 1f 00 55 48 89 e5 48 8b 57 18 <48> 0f b7 4a 10 48 bf 0c 4f e2 c1 ad 90 ff ff be 0c 00 00 00 e8 0f
RSP: 0018:ffffa86640b53da8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffa866402d1000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffa866402d1048 RDI: ffffa86640b53dc8
RBP: ffffa86640b53da8 R08: 0000000000000000 R09: 9c908cd09b9c8c91
R10: ffff90adc056b540 R11: 0000000000000002 R12: 0000000000000000
R13: ffffa86640b53e88 R14: 0000000000000800 R15: fffffffffffffffe
FS:  00007f2a27c2b480(0000) GS:ffff90b0efd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000100e69004 CR4: 00000000001726f0
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x148/0x420
 ? search_bpf_extables+0x5b/0x70
 ? fixup_exception+0x27/0x2c0
 ? exc_page_fault+0x75/0x170
 ? asm_exc_page_fault+0x22/0x30
 ? bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
 bpf_trace_run4+0x68/0xd0
 ? unix_stream_connect+0x1f4/0x6f0
 sk_skb_reason_drop+0x90/0x120
 unix_stream_connect+0x1f4/0x6f0
 __sys_connect+0x7f/0xb0
 __x64_sys_connect+0x14/0x20
 do_syscall_64+0x47/0xc30
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f2a27f296a0
Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 41 ff 0c 00 00 74 17 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 54
RSP: 002b:00007ffe29274f58 EFLAGS: 00000202 ORIG_RAX: 000000000000002a

Fixes: c53795d ("net: add rx_sk to trace_kfree_skb")
Reported-by: Yan Zhai <yan@cloudflare.com>
Closes: https://lore.kernel.org/netdev/Z50zebTRzI962e6X@debian.debian/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Yan Zhai <yan@cloudflare.com>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Feb 1, 2025
Yan Zhai reported a BPF prog could trigger a null-ptr-deref [0]
in trace_kfree_skb if the prog does not check if rx_sk is NULL.

Commit c53795d ("net: add rx_sk to trace_kfree_skb") added
rx_sk to trace_kfree_skb, but rx_sk is optional and could be NULL.

Let's add kfree_skb to raw_tp_null_args[] to let the BPF verifier
validate such a prog and prevent the issue.

Now we fail to load such a prog:

  libbpf: prog 'drop': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0
  ; int BPF_PROG(drop, struct sk_buff *skb, void *location, @ kfree_skb_sk_null.bpf.c:21
  0: (79) r3 = *(u64 *)(r1 +24)
  func 'kfree_skb' arg3 has btf_id 5253 type STRUCT 'sock'
  1: R1=ctx() R3_w=trusted_ptr_or_null_sock(id=1)
  ; bpf_printk("sk: %d, %d\n", sk, sk->__sk_common.skc_family); @ kfree_skb_sk_null.bpf.c:24
  1: (69) r4 = *(u16 *)(r3 +16)
  R3 invalid mem access 'trusted_ptr_or_null_'
  processed 2 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --

Note this fix requires commit 838a10b ("bpf: Augment raw_tp
arguments with PTR_MAYBE_NULL").

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000010
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP
CPU: 6 UID: 0 PID: 348 Comm: sshd Not tainted 6.12.11 #206
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 0f 1f 00 55 48 89 e5 48 8b 57 18 <48> 0f b7 4a 10 48 bf 0c 4f e2 c1 ad 90 ff ff be 0c 00 00 00 e8 0f
RSP: 0018:ffffa86640b53da8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffa866402d1000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffa866402d1048 RDI: ffffa86640b53dc8
RBP: ffffa86640b53da8 R08: 0000000000000000 R09: 9c908cd09b9c8c91
R10: ffff90adc056b540 R11: 0000000000000002 R12: 0000000000000000
R13: ffffa86640b53e88 R14: 0000000000000800 R15: fffffffffffffffe
FS:  00007f2a27c2b480(0000) GS:ffff90b0efd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000100e69004 CR4: 00000000001726f0
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x148/0x420
 ? search_bpf_extables+0x5b/0x70
 ? fixup_exception+0x27/0x2c0
 ? exc_page_fault+0x75/0x170
 ? asm_exc_page_fault+0x22/0x30
 ? bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
 bpf_trace_run4+0x68/0xd0
 ? unix_stream_connect+0x1f4/0x6f0
 sk_skb_reason_drop+0x90/0x120
 unix_stream_connect+0x1f4/0x6f0
 __sys_connect+0x7f/0xb0
 __x64_sys_connect+0x14/0x20
 do_syscall_64+0x47/0xc30
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f2a27f296a0
Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 41 ff 0c 00 00 74 17 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 54
RSP: 002b:00007ffe29274f58 EFLAGS: 00000202 ORIG_RAX: 000000000000002a

Fixes: c53795d ("net: add rx_sk to trace_kfree_skb")
Reported-by: Yan Zhai <yan@cloudflare.com>
Closes: https://lore.kernel.org/netdev/Z50zebTRzI962e6X@debian.debian/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Yan Zhai <yan@cloudflare.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Feb 3, 2025
Yan Zhai reported a BPF prog could trigger a null-ptr-deref [0]
in trace_kfree_skb if the prog does not check if rx_sk is NULL.

Commit c53795d ("net: add rx_sk to trace_kfree_skb") added
rx_sk to trace_kfree_skb, but rx_sk is optional and could be NULL.

Let's add kfree_skb to raw_tp_null_args[] to let the BPF verifier
validate such a prog and prevent the issue.

Now we fail to load such a prog:

  libbpf: prog 'drop': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0
  ; int BPF_PROG(drop, struct sk_buff *skb, void *location, @ kfree_skb_sk_null.bpf.c:21
  0: (79) r3 = *(u64 *)(r1 +24)
  func 'kfree_skb' arg3 has btf_id 5253 type STRUCT 'sock'
  1: R1=ctx() R3_w=trusted_ptr_or_null_sock(id=1)
  ; bpf_printk("sk: %d, %d\n", sk, sk->__sk_common.skc_family); @ kfree_skb_sk_null.bpf.c:24
  1: (69) r4 = *(u16 *)(r3 +16)
  R3 invalid mem access 'trusted_ptr_or_null_'
  processed 2 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --

Note this fix requires commit 838a10b ("bpf: Augment raw_tp
arguments with PTR_MAYBE_NULL").

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000010
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP
CPU: 6 UID: 0 PID: 348 Comm: sshd Not tainted 6.12.11 #206
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 0f 1f 00 55 48 89 e5 48 8b 57 18 <48> 0f b7 4a 10 48 bf 0c 4f e2 c1 ad 90 ff ff be 0c 00 00 00 e8 0f
RSP: 0018:ffffa86640b53da8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffa866402d1000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffa866402d1048 RDI: ffffa86640b53dc8
RBP: ffffa86640b53da8 R08: 0000000000000000 R09: 9c908cd09b9c8c91
R10: ffff90adc056b540 R11: 0000000000000002 R12: 0000000000000000
R13: ffffa86640b53e88 R14: 0000000000000800 R15: fffffffffffffffe
FS:  00007f2a27c2b480(0000) GS:ffff90b0efd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000100e69004 CR4: 00000000001726f0
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x148/0x420
 ? search_bpf_extables+0x5b/0x70
 ? fixup_exception+0x27/0x2c0
 ? exc_page_fault+0x75/0x170
 ? asm_exc_page_fault+0x22/0x30
 ? bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
 bpf_trace_run4+0x68/0xd0
 ? unix_stream_connect+0x1f4/0x6f0
 sk_skb_reason_drop+0x90/0x120
 unix_stream_connect+0x1f4/0x6f0
 __sys_connect+0x7f/0xb0
 __x64_sys_connect+0x14/0x20
 do_syscall_64+0x47/0xc30
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f2a27f296a0
Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 41 ff 0c 00 00 74 17 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 54
RSP: 002b:00007ffe29274f58 EFLAGS: 00000202 ORIG_RAX: 000000000000002a

Fixes: c53795d ("net: add rx_sk to trace_kfree_skb")
Reported-by: Yan Zhai <yan@cloudflare.com>
Closes: https://lore.kernel.org/netdev/Z50zebTRzI962e6X@debian.debian/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Yan Zhai <yan@cloudflare.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20250201030142.62703-1-kuniyu@amazon.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
kernel-patches-daemon-bpf bot pushed a commit that referenced this pull request Feb 3, 2025
Yan Zhai reported a BPF prog could trigger a null-ptr-deref [0]
in trace_kfree_skb if the prog does not check if rx_sk is NULL.

Commit c53795d ("net: add rx_sk to trace_kfree_skb") added
rx_sk to trace_kfree_skb, but rx_sk is optional and could be NULL.

Let's add __nullable suffix to rx_sk to let the BPF verifier
validate such a prog and prevent the issue.

Now we fail to load such a prog:

  libbpf: prog 'drop': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0
  ; int BPF_PROG(drop, struct sk_buff *skb, void *location, @ kfree_skb_sk_null.bpf.c:21
  0: (79) r3 = *(u64 *)(r1 +24)
  func 'kfree_skb' arg3 has btf_id 5253 type STRUCT 'sock'
  1: R1=ctx() R3_w=trusted_ptr_or_null_sock(id=1)
  ; bpf_printk("sk: %d, %d\n", sk, sk->__sk_common.skc_family); @ kfree_skb_sk_null.bpf.c:24
  1: (69) r4 = *(u16 *)(r3 +16)
  R3 invalid mem access 'trusted_ptr_or_null_'
  processed 2 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
  -- END PROG LOAD LOG --

Note this fix requires commit 8aeaed2 ("bpf: Support
__nullable argument suffix for tp_btf").

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000010
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP
CPU: 6 UID: 0 PID: 348 Comm: sshd Not tainted 6.12.11 #206
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 0f 1f 00 55 48 89 e5 48 8b 57 18 <48> 0f b7 4a 10 48 bf 0c 4f e2 c1 ad 90 ff ff be 0c 00 00 00 e8 0f
RSP: 0018:ffffa86640b53da8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffa866402d1000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffa866402d1048 RDI: ffffa86640b53dc8
RBP: ffffa86640b53da8 R08: 0000000000000000 R09: 9c908cd09b9c8c91
R10: ffff90adc056b540 R11: 0000000000000002 R12: 0000000000000000
R13: ffffa86640b53e88 R14: 0000000000000800 R15: fffffffffffffffe
FS:  00007f2a27c2b480(0000) GS:ffff90b0efd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000100e69004 CR4: 00000000001726f0
Call Trace:
 <TASK>
 ? __die+0x1f/0x60
 ? page_fault_oops+0x148/0x420
 ? search_bpf_extables+0x5b/0x70
 ? fixup_exception+0x27/0x2c0
 ? exc_page_fault+0x75/0x170
 ? asm_exc_page_fault+0x22/0x30
 ? bpf_prog_5e21a6db8fcff1aa_drop+0x10/0x2d
 bpf_trace_run4+0x68/0xd0
 ? unix_stream_connect+0x1f4/0x6f0
 sk_skb_reason_drop+0x90/0x120
 unix_stream_connect+0x1f4/0x6f0
 __sys_connect+0x7f/0xb0
 __x64_sys_connect+0x14/0x20
 do_syscall_64+0x47/0xc30
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f2a27f296a0
Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 41 ff 0c 00 00 74 17 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 54
RSP: 002b:00007ffe29274f58 EFLAGS: 00000202 ORIG_RAX: 000000000000002a

Fixes: c53795d ("net: add rx_sk to trace_kfree_skb")
Reported-by: Yan Zhai <yan@cloudflare.com>
Closes: https://lore.kernel.org/netdev/Z50zebTRzI962e6X@debian.debian/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Yan Zhai <yan@cloudflare.com>
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