The tramp_1 to tramp_40 ops is not set in the cfi_stubs in the
bpf_testmod_ops. It fails the struct_ops_multi_pages test after
retiring the unsupported_ops in the earlier patch.

This patch initializes them in a loop during the bpf_testmod_init().
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240722183049.2254692-3-martin.lau@linux.devSigned-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

The bpf_tcp_ca struct_ops currently uses a "u32 unsupported_ops[]"
array to track which ops is not supported.

After cfi_stubs had been added, the function pointer in cfi_stubs is
also NULL for the unsupported ops. Thus, the "u32 unsupported_ops[]"
becomes redundant. This observation was originally brought up in the
bpf/cfi discussion:
https://lore.kernel.org/bpf/CAADnVQJoEkdjyCEJRPASjBw1QGsKYrF33QdMGc1RZa9b88bAEA@mail.gmail.com/

The recent bpf qdisc patch (https://lore.kernel.org/bpf/20240714175130.4051012-6-amery.hung@bytedance.com/)
also needs to specify quite many unsupported ops. It is a good time
to clean it up.

This patch removes the need of "u32 unsupported_ops[]" and tests for null-ness
in the cfi_stubs instead.

Testing the cfi_stubs is done in a new function bpf_struct_ops_supported().
The verifier will call bpf_struct_ops_supported() when loading the
struct_ops program. The ".check_member" is removed from the bpf_tcp_ca
in this patch. ".check_member" could still be useful for other subsytems
to enforce other restrictions (e.g. sched_ext checks for prog->sleepable).

To keep the same error return, ENOTSUPP is used.

Cc: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240722183049.2254692-2-martin.lau@linux.devSigned-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

This commit adds sample output for net attach/detach on
tcx subcommand.
Signed-off-by: Tao Chen <chen.dylane@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240721144252.96264-1-chen.dylane@gmail.comSigned-off-by: Andrii Nakryiko <andrii@kernel.org>

This commit adds bash-completion for attaching tcx program on interface.
Signed-off-by: Tao Chen <chen.dylane@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240721144238.96246-1-chen.dylane@gmail.comSigned-off-by: Andrii Nakryiko <andrii@kernel.org>

Now, attach/detach tcx prog supported in libbpf, so we can add new
command 'bpftool attach/detach tcx' to attach tcx prog with bpftool
for user.

 # bpftool prog load tc_prog.bpf.o /sys/fs/bpf/tc_prog
 # bpftool prog show
	...
	192: sched_cls  name tc_prog  tag 187aeb611ad00cfc  gpl
	loaded_at 2024-07-11T15:58:16+0800  uid 0
	xlated 152B  jited 97B  memlock 4096B  map_ids 100,99,97
	btf_id 260
 # bpftool net attach tcx_ingress name tc_prog dev lo
 # bpftool net
	...
	tc:
	lo(1) tcx/ingress tc_prog prog_id 29

 # bpftool net detach tcx_ingress dev lo
 # bpftool net
	...
	tc:
 # bpftool net attach tcx_ingress name tc_prog dev lo
 # bpftool net
	tc:
	lo(1) tcx/ingress tc_prog prog_id 29

Test environment: ubuntu_22_04, 6.7.0-060700-generic
Signed-off-by: Tao Chen <chen.dylane@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240721144221.96228-1-chen.dylane@gmail.comSigned-off-by: Andrii Nakryiko <andrii@kernel.org>

This commit no logical changed, just increases code readability and
facilitates TCX prog expansion, which will be implemented in the next
patch.
Signed-off-by: Tao Chen <chen.dylane@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240721143353.95980-2-chen.dylane@gmail.comSigned-off-by: Andrii Nakryiko <andrii@kernel.org>

Leon Hwang says:

====================
bpf: Fix tailcall hierarchy

This patchset fixes a tailcall hierarchy issue.

The issue is confirmed in the discussions of
"bpf, x64: Fix tailcall infinite loop" [0].

The issue has been resolved on both x86_64 and arm64 [1].

I provide a long commit message in the "bpf, x64: Fix tailcall hierarchy"
patch to describe how the issue happens and how this patchset resolves the
issue in details.

How does this patchset resolve the issue?

In short, it stores tail_call_cnt on the stack of main prog, and propagates
tail_call_cnt_ptr to its subprogs.

First, at the prologue of main prog, it initializes tail_call_cnt and
prepares tail_call_cnt_ptr. And at the prologue of subprog, it reuses
the tail_call_cnt_ptr from caller.

Then, when a tailcall happens, it increments tail_call_cnt by its pointer.

v5 -> v6:
  * Address comments from Eduard:
    * Add JITed dumping along annotating comments
    * Rewrite two selftests with RUN_TESTS macro.

v4 -> v5:
  * Solution changes from tailcall run ctx to tail_call_cnt and its pointer.
    It's because v4 solution is unable to handle the case that there is no
    tailcall in subprog but there is tailcall in EXT prog which attaches to
    the subprog.

v3 -> v4:
  * Solution changes from per-task tail_call_cnt to tailcall run ctx.
    As for per-cpu/per-task solution, there is a case it is unable to handle [2].

v2 -> v3:
  * Solution changes from percpu tail_call_cnt to tail_call_cnt at task_struct.

v1 -> v2:
  * Solution changes from extra run-time call insn to percpu tail_call_cnt.
  * Address comments from Alexei:
    * Use percpu tail_call_cnt.
    * Use asm to make sure no callee saved registers are touched.

RFC v2 -> v1:
  * Solution changes from propagating tail_call_cnt with its pointer to extra
    run-time call insn.
  * Address comments from Maciej:
    * Replace all memcpy(prog, x86_nops[5], X86_PATCH_SIZE) with
        emit_nops(&prog, X86_PATCH_SIZE)

RFC v1 -> RFC v2:
  * Address comments from Stanislav:
    * Separate moving emit_nops() as first patch.

Links:
[0] https://lore.kernel.org/bpf/6203dd01-789d-f02c-5293-def4c1b18aef@gmail.com/
[1] https://github.com/kernel-patches/bpf/pull/7350/checks
[2] https://lore.kernel.org/bpf/CAADnVQK1qF+uBjwom2s2W-yEmgd_3rGi5Nr+KiV3cW0T+UPPfA@mail.gmail.com/
====================

Link: https://lore.kernel.org/r/20240714123902.32305-1-hffilwlqm@gmail.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

Add some test cases to confirm the tailcall hierarchy issue has been fixed.

On x64, the selftests result is:

cd tools/testing/selftests/bpf && ./test_progs -t tailcalls
327/18  tailcalls/tailcall_bpf2bpf_hierarchy_1:OK
327/19  tailcalls/tailcall_bpf2bpf_hierarchy_fentry:OK
327/20  tailcalls/tailcall_bpf2bpf_hierarchy_fexit:OK
327/21  tailcalls/tailcall_bpf2bpf_hierarchy_fentry_fexit:OK
327/22  tailcalls/tailcall_bpf2bpf_hierarchy_fentry_entry:OK
327/23  tailcalls/tailcall_bpf2bpf_hierarchy_2:OK
327/24  tailcalls/tailcall_bpf2bpf_hierarchy_3:OK
327     tailcalls:OK
Summary: 1/24 PASSED, 0 SKIPPED, 0 FAILED

On arm64, the selftests result is:

cd tools/testing/selftests/bpf && ./test_progs -t tailcalls
327/18  tailcalls/tailcall_bpf2bpf_hierarchy_1:OK
327/19  tailcalls/tailcall_bpf2bpf_hierarchy_fentry:OK
327/20  tailcalls/tailcall_bpf2bpf_hierarchy_fexit:OK
327/21  tailcalls/tailcall_bpf2bpf_hierarchy_fentry_fexit:OK
327/22  tailcalls/tailcall_bpf2bpf_hierarchy_fentry_entry:OK
327/23  tailcalls/tailcall_bpf2bpf_hierarchy_2:OK
327/24  tailcalls/tailcall_bpf2bpf_hierarchy_3:OK
327     tailcalls:OK
Summary: 1/24 PASSED, 0 SKIPPED, 0 FAILED
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Leon Hwang <hffilwlqm@gmail.com>
Link: https://lore.kernel.org/r/20240714123902.32305-4-hffilwlqm@gmail.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

This patch fixes a tailcall issue caused by abusing the tailcall in
bpf2bpf feature on arm64 like the way of "bpf, x64: Fix tailcall
hierarchy".

On arm64, when a tail call happens, it uses tail_call_cnt_ptr to
increment tail_call_cnt, too.

At the prologue of main prog, it has to initialize tail_call_cnt and
prepare tail_call_cnt_ptr.

At the prologue of subprog, it pushes x26 register twice, and does not
initialize tail_call_cnt.

At the epilogue, it pops x26 twice, no matter whether it is main prog or
subprog.

Fixes: d4609a5d ("bpf, arm64: Keep tail call count across bpf2bpf calls")
Acked-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Leon Hwang <hffilwlqm@gmail.com>
Link: https://lore.kernel.org/r/20240714123902.32305-3-hffilwlqm@gmail.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

This patch fixes a tailcall issue caused by abusing the tailcall in
bpf2bpf feature.

As we know, tail_call_cnt propagates by rax from caller to callee when
to call subprog in tailcall context. But, like the following example,
MAX_TAIL_CALL_CNT won't work because of missing tail_call_cnt
back-propagation from callee to caller.

\#include <linux/bpf.h>
\#include <bpf/bpf_helpers.h>
\#include "bpf_legacy.h"

struct {
	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
	__uint(max_entries, 1);
	__uint(key_size, sizeof(__u32));
	__uint(value_size, sizeof(__u32));
} jmp_table SEC(".maps");

int count = 0;

static __noinline
int subprog_tail1(struct __sk_buff *skb)
{
	bpf_tail_call_static(skb, &jmp_table, 0);
	return 0;
}

static __noinline
int subprog_tail2(struct __sk_buff *skb)
{
	bpf_tail_call_static(skb, &jmp_table, 0);
	return 0;
}

SEC("tc")
int entry(struct __sk_buff *skb)
{
	volatile int ret = 1;

	count++;
	subprog_tail1(skb);
	subprog_tail2(skb);

	return ret;
}

char __license[] SEC("license") = "GPL";

At run time, the tail_call_cnt in entry() will be propagated to
subprog_tail1() and subprog_tail2(). But, when the tail_call_cnt in
subprog_tail1() updates when bpf_tail_call_static(), the tail_call_cnt
in entry() won't be updated at the same time. As a result, in entry(),
when tail_call_cnt in entry() is less than MAX_TAIL_CALL_CNT and
subprog_tail1() returns because of MAX_TAIL_CALL_CNT limit,
bpf_tail_call_static() in suprog_tail2() is able to run because the
tail_call_cnt in subprog_tail2() propagated from entry() is less than
MAX_TAIL_CALL_CNT.

So, how many tailcalls are there for this case if no error happens?

From top-down view, does it look like hierarchy layer and layer?

With this view, there will be 2+4+8+...+2^33 = 2^34 - 2 = 17,179,869,182
tailcalls for this case.

How about there are N subprog_tail() in entry()? There will be almost
N^34 tailcalls.

Then, in this patch, it resolves this case on x86_64.

In stead of propagating tail_call_cnt from caller to callee, it
propagates its pointer, tail_call_cnt_ptr, tcc_ptr for short.

However, where does it store tail_call_cnt?

It stores tail_call_cnt on the stack of main prog. When tail call
happens in subprog, it increments tail_call_cnt by tcc_ptr.

Meanwhile, it stores tail_call_cnt_ptr on the stack of main prog, too.

And, before jump to tail callee, it has to pop tail_call_cnt and
tail_call_cnt_ptr.

Then, at the prologue of subprog, it must not make rax as
tail_call_cnt_ptr again. It has to reuse tail_call_cnt_ptr from caller.

As a result, at run time, it has to recognize rax is tail_call_cnt or
tail_call_cnt_ptr at prologue by:

1. rax is tail_call_cnt if rax is <= MAX_TAIL_CALL_CNT.
2. rax is tail_call_cnt_ptr if rax is > MAX_TAIL_CALL_CNT, because a
   pointer won't be <= MAX_TAIL_CALL_CNT.

Here's an example to dump JITed.

struct {
	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
	__uint(max_entries, 1);
	__uint(key_size, sizeof(__u32));
	__uint(value_size, sizeof(__u32));
} jmp_table SEC(".maps");

int count = 0;

static __noinline
int subprog_tail(struct __sk_buff *skb)
{
	bpf_tail_call_static(skb, &jmp_table, 0);
	return 0;
}

SEC("tc")
int entry(struct __sk_buff *skb)
{
	int ret = 1;

	count++;
	subprog_tail(skb);
	subprog_tail(skb);

	return ret;
}

When bpftool p d j id 42:

int entry(struct __sk_buff * skb):
bpf_prog_0c0f4c2413ef19b1_entry:
; int entry(struct __sk_buff *skb)
   0:	endbr64
   4:	nopl	(%rax,%rax)
   9:	xorq	%rax, %rax		;; rax = 0 (tail_call_cnt)
   c:	pushq	%rbp
   d:	movq	%rsp, %rbp
  10:	endbr64
  14:	cmpq	$33, %rax		;; if rax > 33, rax = tcc_ptr
  18:	ja	0x20			;; if rax > 33 goto 0x20 ---+
  1a:	pushq	%rax			;; [rbp - 8] = rax = 0      |
  1b:	movq	%rsp, %rax		;; rax = rbp - 8            |
  1e:	jmp	0x21			;; ---------+               |
  20:	pushq	%rax			;; <--------|---------------+
  21:	pushq	%rax			;; <--------+ [rbp - 16] = rax
  22:	pushq	%rbx			;; callee saved
  23:	movq	%rdi, %rbx		;; rbx = skb (callee saved)
; count++;
  26:	movabsq	$-82417199407104, %rdi
  30:	movl	(%rdi), %esi
  33:	addl	$1, %esi
  36:	movl	%esi, (%rdi)
; subprog_tail(skb);
  39:	movq	%rbx, %rdi		;; rdi = skb
  3c:	movq	-16(%rbp), %rax		;; rax = tcc_ptr
  43:	callq	0x80			;; call subprog_tail()
; subprog_tail(skb);
  48:	movq	%rbx, %rdi		;; rdi = skb
  4b:	movq	-16(%rbp), %rax		;; rax = tcc_ptr
  52:	callq	0x80			;; call subprog_tail()
; return ret;
  57:	movl	$1, %eax
  5c:	popq	%rbx
  5d:	leave
  5e:	retq

int subprog_tail(struct __sk_buff * skb):
bpf_prog_3a140cef239a4b4f_subprog_tail:
; int subprog_tail(struct __sk_buff *skb)
   0:	endbr64
   4:	nopl	(%rax,%rax)
   9:	nopl	(%rax)			;; do not touch tail_call_cnt
   c:	pushq	%rbp
   d:	movq	%rsp, %rbp
  10:	endbr64
  14:	pushq	%rax			;; [rbp - 8]  = rax (tcc_ptr)
  15:	pushq	%rax			;; [rbp - 16] = rax (tcc_ptr)
  16:	pushq	%rbx			;; callee saved
  17:	pushq	%r13			;; callee saved
  19:	movq	%rdi, %rbx		;; rbx = skb
; asm volatile("r1 = %[ctx]\n\t"
  1c:	movabsq	$-105487587488768, %r13	;; r13 = jmp_table
  26:	movq	%rbx, %rdi		;; 1st arg, skb
  29:	movq	%r13, %rsi		;; 2nd arg, jmp_table
  2c:	xorl	%edx, %edx		;; 3rd arg, index = 0
  2e:	movq	-16(%rbp), %rax		;; rax = [rbp - 16] (tcc_ptr)
  35:	cmpq	$33, (%rax)
  39:	jae	0x4e			;; if *tcc_ptr >= 33 goto 0x4e --------+
  3b:	jmp	0x4e			;; jmp bypass, toggled by poking       |
  40:	addq	$1, (%rax)		;; (*tcc_ptr)++                        |
  44:	popq	%r13			;; callee saved                        |
  46:	popq	%rbx			;; callee saved                        |
  47:	popq	%rax			;; undo rbp-16 push                    |
  48:	popq	%rax			;; undo rbp-8  push                    |
  49:	nopl	(%rax,%rax)		;; tail call target, toggled by poking |
; return 0;				;;                                     |
  4e:	popq	%r13			;; restore callee saved <--------------+
  50:	popq	%rbx			;; restore callee saved
  51:	leave
  52:	retq

Furthermore, when trampoline is the caller of bpf prog, which is
tail_call_reachable, it is required to propagate rax through trampoline.

Fixes: ebf7d1f5 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT")
Fixes: e411901c ("bpf: allow for tailcalls in BPF subprograms for x64 JIT")
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Leon Hwang <hffilwlqm@gmail.com>
Link: https://lore.kernel.org/r/20240714123902.32305-2-hffilwlqm@gmail.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

Eduard Zingerman says:

====================
bpf: track find_equal_scalars history on per-instruction level

This is a fix for precision tracking bug reported in [0].
It supersedes my previous attempt to fix similar issue in commit [1].
Here is a minimized test case from [0]:

    0:  call bpf_get_prandom_u32;
    1:  r7 = r0;
    2:  r8 = r0;
    3:  call bpf_get_prandom_u32;
    4:  if r0 > 1 goto +0;
    /* --- checkpoint #1: r7.id=1, r8.id=1 --- */
    5:  if r8 >= r0 goto 9f;
    6:  r8 += r8;
    /* --- checkpoint #2: r7.id=1, r8.id=0 --- */
    7:  if r7 == 0 goto 9f;
    8:  r0 /= 0;
    /* --- checkpoint #3 --- */
    9:  r0 = 42;
    10: exit;

W/o this fix verifier incorrectly assumes that instruction at label
(8) is unreachable. The issue is caused by failure to infer
precision mark for r0 at checkpoint #1:
- first verification path is:
  - (0-4): r0 range [0,1];
  - (5): r8 range [0,0], propagated to r7;
  - (6): r8.id is reset;
  - (7): jump is predicted to happen;
  - (9-10): safe exit.
- when jump at (7) is predicted mark_chain_precision() for r7 is
  called and backtrack_insn() proceeds as follows:
  - at (7) r7 is marked as precise;
  - at (5) r8 is not currently tracked and thus r0 is not marked;
  - at (4-5) boundary logic from [1] is triggered and r7,r8 are marked
    as precise;
  - => r0 precision mark is missed.
- when second branch of (4) is considered, verifier prunes the state
  because r0 is not marked as precise in the visited state.

Basically, backtracking logic fails to notice that at (5)
range information is gained for both r7 and r8, and thus both
r8 and r0 have to be marked as precise.
This happens because [1] can only account for such range
transfers at parent/child state boundaries.

The solution suggested by Andrii Nakryiko in [0] is to use jump
history to remember which registers gained range as a result of
find_equal_scalars() [renamed to sync_linked_regs()] and use
this information in backtrack_insn().
Which is what this patch-set does.

The patch-set uses u64 value as a vector of 10-bit values that
identify registers gaining range in find_equal_scalars().
This amounts to maximum of 6 possible values.
To check if such capacity is sufficient I've instrumented kernel
to track a histogram for maximal amount of registers that gain range
in find_equal_scalars per program verification [2].
Measurements done for verifier selftests and Cilium bpf object files
from [3] show that number of such registers is *always* <= 4 and
in 98% of cases it is <= 2.

When tested on a subset of selftests identified by
selftests/bpf/veristat.cfg and Cilium bpf object files from [3]
this patch-set has minimal verification performance impact:

File                      Program                   Insns   (DIFF)  States (DIFF)
------------------------  ------------------------  --------------  -------------
bpf_host.o                tail_handle_nat_fwd_ipv4    -75 (-0.61%)    -3 (-0.39%)
pyperf600_nounroll.bpf.o  on_event                  +1673 (+0.33%)    +3 (+0.01%)

[0] https://lore.kernel.org/bpf/CAEf4BzZ0xidVCqB47XnkXcNhkPWF6_nTV7yt+_Lf0kcFEut2Mg@mail.gmail.com/
[1] commit 904e6ddf ("bpf: Use scalar ids in mark_chain_precision()")
[2] https://github.com/eddyz87/bpf/tree/find-equal-scalars-in-jump-history-with-stats
[3] https://github.com/anakryiko/cilium

Changes:
- v2 -> v3:
  A number of stylistic changes suggested by Andrii:
  - renamings:
    - struct reg_or_spill   -> linked_reg;
    - find_equal_scalars()  -> collect_linked_regs;
    - copy_known_reg()      -> sync_linked_regs;
  - collect_linked_regs() now returns linked regs set of
    size 2 or larger;
  - dropped usage of bit fields in struct linked_reg;
  - added a patch changing references to find_equal_scalars() in
    selftests comments.
- v1 -> v2:
  - patch "bpf: replace env->cur_hist_ent with a getter function" is
    dropped (Andrii);
  - added structure linked_regs and helper functions to [de]serialize
    u64 value as such structure (Andrii);
  - bt_set_equal_scalars() renamed to bt_sync_linked_regs(), moved to
    start and end of backtrack_insn() in order to untie linked
    register logic from conditional jumps backtracking.
    Andrii requested a more radical change of moving linked registers
    processing to bt_set_xxx() functions, I did an experiment in this
    direction:
    https://github.com/eddyz87/bpf/tree/find-equal-scalars-in-jump-history--linked-regs-in-bt-set-reg
    the end result of the experiment seems much uglier than version
    presented in v2.

Revisions:
- v1: https://lore.kernel.org/bpf/20240222005005.31784-1-eddyz87@gmail.com/
- v2: https://lore.kernel.org/bpf/20240705205851.2635794-1-eddyz87@gmail.com/
====================

Link: https://lore.kernel.org/r/20240718202357.1746514-1-eddyz87@gmail.comSigned-off-by: Andrii Nakryiko <andrii@kernel.org>

find_equal_scalars() is renamed to sync_linked_regs(),
this commit updates existing references in the selftests comments.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240718202357.1746514-5-eddyz87@gmail.com

Add a few test cases to verify precision tracking for scalars gaining
range because of sync_linked_regs():
- check what happens when more than 6 registers might gain range in
  sync_linked_regs();
- check if precision is propagated correctly when operand of
  conditional jump gained range in sync_linked_regs() and one of
  linked registers is marked precise;
- check if precision is propagated correctly when operand of
  conditional jump gained range in sync_linked_regs() and a
  other-linked operand of the conditional jump is marked precise;
- add a minimized reproducer for precision tracking bug reported in [0];
- Check that mark_chain_precision() for one of the conditional jump
  operands does not trigger equal scalars precision propagation.

[0] https://lore.kernel.org/bpf/CAEf4BzZ0xidVCqB47XnkXcNhkPWF6_nTV7yt+_Lf0kcFEut2Mg@mail.gmail.com/Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240718202357.1746514-4-eddyz87@gmail.com

Function mark_precise_scalar_ids() is superseded by
bt_sync_linked_regs() and equal scalars tracking in jump history.
mark_precise_scalar_ids() propagates precision over registers sharing
same ID on parent/child state boundaries, while jump history records
allow bt_sync_linked_regs() to propagate same information with
instruction level granularity, which is strictly more precise.

This commit removes mark_precise_scalar_ids() and updates test cases
in progs/verifier_scalar_ids to reflect new verifier behavior.

The tests are updated in the following manner:
- mark_precise_scalar_ids() propagated precision regardless of
  presence of conditional jumps, while new jump history based logic
  only kicks in when conditional jumps are present.
  Hence test cases are augmented with conditional jumps to still
  trigger precision propagation.
- As equal scalars tracking no longer relies on parent/child state
  boundaries some test cases are no longer interesting,
  such test cases are removed, namely:
  - precision_same_state and precision_cross_state are superseded by
    linked_regs_bpf_k;
  - precision_same_state_broken_link and equal_scalars_broken_link
    are superseded by linked_regs_broken_link.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240718202357.1746514-3-eddyz87@gmail.com

Use bpf_verifier_state->jmp_history to track which registers were
updated by find_equal_scalars() (renamed to collect_linked_regs())
when conditional jump was verified. Use recorded information in
backtrack_insn() to propagate precision.

E.g. for the following program:

            while verifying instructions
  1: r1 = r0              |
  2: if r1 < 8  goto ...  | push r0,r1 as linked registers in jmp_history
  3: if r0 > 16 goto ...  | push r0,r1 as linked registers in jmp_history
  4: r2 = r10             |
  5: r2 += r0             v mark_chain_precision(r0)

            while doing mark_chain_precision(r0)
  5: r2 += r0             | mark r0 precise
  4: r2 = r10             |
  3: if r0 > 16 goto ...  | mark r0,r1 as precise
  2: if r1 < 8  goto ...  | mark r0,r1 as precise
  1: r1 = r0              v

Technically, do this as follows:
- Use 10 bits to identify each register that gains range because of
  sync_linked_regs():
  - 3 bits for frame number;
  - 6 bits for register or stack slot number;
  - 1 bit to indicate if register is spilled.
- Use u64 as a vector of 6 such records + 4 bits for vector length.
- Augment struct bpf_jmp_history_entry with a field 'linked_regs'
  representing such vector.
- When doing check_cond_jmp_op() remember up to 6 registers that
  gain range because of sync_linked_regs() in such a vector.
- Don't propagate range information and reset IDs for registers that
  don't fit in 6-value vector.
- Push a pair {instruction index, linked registers vector}
  to bpf_verifier_state->jmp_history.
- When doing backtrack_insn() check if any of recorded linked
  registers is currently marked precise, if so mark all linked
  registers as precise.

This also requires fixes for two test_verifier tests:
- precise: test 1
- precise: test 2

Both tests contain the following instruction sequence:

19: (bf) r2 = r9                      ; R2=scalar(id=3) R9=scalar(id=3)
20: (a5) if r2 < 0x8 goto pc+1        ; R2=scalar(id=3,umin=8)
21: (95) exit
22: (07) r2 += 1                      ; R2_w=scalar(id=3+1,...)
23: (bf) r1 = r10                     ; R1_w=fp0 R10=fp0
24: (07) r1 += -8                     ; R1_w=fp-8
25: (b7) r3 = 0                       ; R3_w=0
26: (85) call bpf_probe_read_kernel#113

The call to bpf_probe_read_kernel() at (26) forces r2 to be precise.
Previously, this forced all registers with same id to become precise
immediately when mark_chain_precision() is called.
After this change, the precision is propagated to registers sharing
same id only when 'if' instruction is backtracked.
Hence verification log for both tests is changed:
regs=r2,r9 -> regs=r2 for instructions 25..20.

Fixes: 904e6ddf ("bpf: Use scalar ids in mark_chain_precision()")
Reported-by: Hao Sun <sunhao.th@gmail.com>
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240718202357.1746514-2-eddyz87@gmail.com

Closes: https://lore.kernel.org/bpf/CAEf4BzZ0xidVCqB47XnkXcNhkPWF6_nTV7yt+_Lf0kcFEut2Mg@mail.gmail.com/

Make use of -M compiler options when building .test.o objects to
generate .d files and avoid re-building all tests every time.

Previously, if a single test bpf program under selftests/bpf/progs/*.c
has changed, make would rebuild all the *.bpf.o, *.skel.h and *.test.o
objects, which is a lot of unnecessary work.

A typical dependency chain is:
progs/x.c -> x.bpf.o -> x.skel.h -> x.test.o -> trunner_binary

However for many tests it's not a 1:1 mapping by name, and so far
%.test.o have been simply dependent on all %.skel.h files, and
%.skel.h files on all %.bpf.o objects.

Avoid full rebuilds by instructing the compiler (via -MMD) to
produce *.d files with real dependencies, and appropriately including
them. Exploit make feature that rebuilds included makefiles if they
were changed by setting %.test.d as prerequisite for %.test.o files.

A couple of examples of compilation time speedup (after the first
clean build):

$ touch progs/verifier_and.c && time make -j8
Before: real	0m16.651s
After:  real	0m2.245s
$ touch progs/read_vsyscall.c && time make -j8
Before: real	0m15.743s
After:  real	0m1.575s

A drawback of this change is that now there is an overhead due to make
processing lots of .d files, which potentially may slow down unrelated
targets. However a time to make all from scratch hasn't changed
significantly:

$ make clean && time make -j8
Before: real	1m31.148s
After:  real	1m30.309s
Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Ihor Solodrai <ihor.solodrai@pm.me>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/VJihUTnvtwEgv_mOnpfy7EgD9D2MPNoHO-MlANeLIzLJPGhDeyOuGKIYyKgk0O6KPjfM-MuhtvPwZcngN8WFqbTnTRyCSMc2aMZ1ODm1T_g=@pm.me

Single characters should be put into a sequence.
Thus use the corresponding function “seq_putc” for two selected calls.

This issue was transformed by using the Coccinelle software.
Suggested-by: Christophe Jaillet <christophe.jaillet@wanadoo.fr>
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/abde0992-3d71-44d2-ab27-75b382933a22@web.de

Single line breaks should occasionally be put into a sequence.
Thus use the corresponding function “seq_putc”.

This issue was transformed by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/e26b7df9-cd63-491f-85e8-8cabe60a85e5@web.de

Geliang Tang says:

====================
v3:
 - patch 2:
   - clear errno before connect_to_fd_opts.
   - print err logs in run_test.
   - set err to -1 when fd >= 0.
 - patch 3:
   - drop "int err".

v2:
 - update patch 2 as Martin suggested.

This is the 9th part of series "use network helpers" all BPF selftests
wide.

Patches 1-2 update network helpers interfaces suggested by Martin.
Patch 3 adds a new helper connect_to_addr_str() as Martin suggested
instead of adding connect_fd_to_addr_str().
Patch 4 uses this newly added helper in make_client().
Patch 5 uses make_client() in sk_lookup and drop make_socket().
====================
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

Similar to connect_to_addr() helper for connecting to a server with the
given sockaddr_storage type address, this patch adds a new helper named
connect_to_addr_str() for connecting to a server with the given string
type address "addr_str", together with its "family" and "port" as other
parameters of connect_to_addr_str().

In connect_to_addr_str(), the parameters "family", "addr_str" and "port"
are used to create a sockaddr_storage type address "addr" by invoking
make_sockaddr(). Then pass this "addr" together with "addrlen", "type"
and "opts" to connect_to_addr().
Suggested-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Link: https://lore.kernel.org/r/647e82170831558dbde132a7a3d86df660dba2c4.1721282219.git.tanggeliang@kylinos.cnSigned-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

The struct member "must_fail" of network_helper_opts() is only used in
cgroup_v1v2 tests, it makes sense to drop it from network_helper_opts.

Return value (fd) of connect_to_fd_opts() and the expect errno (EPERM)
can be checked in cgroup_v1v2.c directly, no need to check them in
connect_fd_to_addr() in network_helpers.c.

This also makes connect_fd_to_addr() function useless. It can be replaced
by connect().
Suggested-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Link: https://lore.kernel.org/r/3faf336019a9a48e2e8951f4cdebf19e3ac6e441.1721282219.git.tanggeliang@kylinos.cnSigned-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

The "type" parameter of connect_to_fd_opts() is redundant of "server_fd".
Since the "type" can be obtained inside by invoking getsockopt(SO_TYPE),
without passing it in as a parameter.

This patch drops the "type" parameter of connect_to_fd_opts() and updates
its callers.
Suggested-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Link: https://lore.kernel.org/r/50d8ce7ab7ab0c0f4d211fc7cc4ebe3d3f63424c.1721282219.git.tanggeliang@kylinos.cnSigned-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

Pull networking fixes from Jakub Kicinski:
 "Including fixes from bpf and netfilter.

  A lot of networking people were at a conference last week, busy
  catching COVID, so relatively short PR.

  Current release - regressions:

   - tcp: process the 3rd ACK with sk_socket for TFO and MPTCP

  Current release - new code bugs:

   - l2tp: protect session IDR and tunnel session list with one lock,
     make sure the state is coherent to avoid a warning

   - eth: bnxt_en: update xdp_rxq_info in queue restart logic

   - eth: airoha: fix location of the MBI_RX_AGE_SEL_MASK field

  Previous releases - regressions:

   - xsk: require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len,
     the field reuses previously un-validated pad

  Previous releases - always broken:

   - tap/tun: drop short frames to prevent crashes later in the stack

   - eth: ice: add a per-VF limit on number of FDIR filters

   - af_unix: disable MSG_OOB handling for sockets in sockmap/sockhash"

* tag 'net-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (34 commits)
  tun: add missing verification for short frame
  tap: add missing verification for short frame
  mISDN: Fix a use after free in hfcmulti_tx()
  gve: Fix an edge case for TSO skb validity check
  bnxt_en: update xdp_rxq_info in queue restart logic
  tcp: process the 3rd ACK with sk_socket for TFO/MPTCP
  selftests/bpf: Add XDP_UMEM_TX_METADATA_LEN to XSK TX metadata test
  xsk: Require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len
  bpf: Fix a segment issue when downgrading gso_size
  net: mediatek: Fix potential NULL pointer dereference in dummy net_device handling
  MAINTAINERS: make Breno the netconsole maintainer
  MAINTAINERS: Update bonding entry
  net: nexthop: Initialize all fields in dumped nexthops
  net: stmmac: Correct byte order of perfect_match
  selftests: forwarding: skip if kernel not support setting bridge fdb learning limit
  tipc: Return non-zero value from tipc_udp_addr2str() on error
  netfilter: nft_set_pipapo_avx2: disable softinterrupts
  ice: Fix recipe read procedure
  ice: Add a per-VF limit on number of FDIR filters
  net: bonding: correctly annotate RCU in bond_should_notify_peers()
  ...

Pull printk updates from Petr Mladek:

 - trivial printk changes

The bigger "real" printk work is still being discussed.

* tag 'printk-for-6.11-trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  vsprintf: add missing MODULE_DESCRIPTION() macro
  printk: Rename console_replay_all() and update context

Pull sysctl constification from Joel Granados:
 "Treewide constification of the ctl_table argument of proc_handlers
  using a coccinelle script and some manual code formatting fixups.

  This is a prerequisite to moving the static ctl_table structs into
  read-only data section which will ensure that proc_handler function
  pointers cannot be modified"

* tag 'constfy-sysctl-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl:
  sysctl: treewide: constify the ctl_table argument of proc_handlers

Pull EFI fixes from Ard Biesheuvel:

 - Wipe screen_info after allocating it from the heap - used by arm32
   and EFI zboot, other EFI architectures allocate it statically

 - Revert to allocating boot_params from the heap on x86 when entering
   via the native PE entrypoint, to work around a regression on older
   Dell hardware

* tag 'efi-fixes-for-v6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  x86/efistub: Revert to heap allocated boot_params for PE entrypoint
  efi/libstub: Zero initialize heap allocated struct screen_info

Pull kgdb updates from Daniel Thompson:
 "Three small changes this cycle:

   - Clean up an architecture abstraction that is no longer needed
     because all the architectures have converged.

   - Actually use the prompt argument to kdb_position_cursor() instead
     of ignoring it (functionally this fix is a nop but that was due to
     luck rather than good judgement)

   - Fix a -Wformat-security warning"

* tag 'kgdb-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
  kdb: Get rid of redundant kdb_curr_task()
  kdb: Use the passed prompt in kdb_position_cursor()
  kdb: address -Wformat-security warnings

Pull MIPS updates from Thomas Bogendoerfer:

 - Use improved timer sync for Loongson64

 - Fix address of GCR_ACCESS register

 - Add missing MODULE_DESCRIPTION

* tag 'mips_6.11_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  mips: sibyte: add missing MODULE_DESCRIPTION() macro
  MIPS: SMP-CPS: Fix address for GCR_ACCESS register for CM3 and later
  MIPS: Loongson64: Switch to SYNC_R4K

Merge tag 'parisc-for-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

Pull parisc updates from Helge Deller:
 "The gettimeofday() and clock_gettime() syscalls are now available as
  vDSO functions, and Dave added a patch which allows to use NVMe cards
  in the PCI slots as fast and easy alternative to SCSI discs.

  Summary:

   - add gettimeofday() and clock_gettime() vDSO functions

   - enable PCI_MSI_ARCH_FALLBACKS to allow PCI to PCIe bridge adaptor
     with PCIe NVME card to function in parisc machines

   - allow users to reduce kernel unaligned runtime warnings

   - minor code cleanups"

* tag 'parisc-for-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Add support for CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
  parisc: Use max() to calculate parisc_tlb_flush_threshold
  parisc: Fix warning at drivers/pci/msi/msi.h:121
  parisc: Add 64-bit gettimeofday() and clock_gettime() vDSO functions
  parisc: Add 32-bit gettimeofday() and clock_gettime() vDSO functions
  parisc: Clean up unistd.h file

Pull UML updates from Richard Weinberger:

 - Support for preemption

 - i386 Rust support

 - Huge cleanup by Benjamin Berg

 - UBSAN support

 - Removal of dead code

* tag 'uml-for-linus-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: (41 commits)
  um: vector: always reset vp->opened
  um: vector: remove vp->lock
  um: register power-off handler
  um: line: always fill *error_out in setup_one_line()
  um: remove pcap driver from documentation
  um: Enable preemption in UML
  um: refactor TLB update handling
  um: simplify and consolidate TLB updates
  um: remove force_flush_all from fork_handler
  um: Do not flush MM in flush_thread
  um: Delay flushing syscalls until the thread is restarted
  um: remove copy_context_skas0
  um: remove LDT support
  um: compress memory related stub syscalls while adding them
  um: Rework syscall handling
  um: Add generic stub_syscall6 function
  um: Create signal stack memory assignment in stub_data
  um: Remove stub-data.h include from common-offsets.h
  um: time-travel: fix signal blocking race/hang
  um: time-travel: remove time_exit()
  ...

Merge tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the big set of driver core changes for 6.11-rc1.

  Lots of stuff in here, with not a huge diffstat, but apis are evolving
  which required lots of files to be touched. Highlights of the changes
  in here are:

   - platform remove callback api final fixups (Uwe took many releases
     to get here, finally!)

   - Rust bindings for basic firmware apis and initial driver-core
     interactions.

     It's not all that useful for a "write a whole driver in rust" type
     of thing, but the firmware bindings do help out the phy rust
     drivers, and the driver core bindings give a solid base on which
     others can start their work.

     There is still a long way to go here before we have a multitude of
     rust drivers being added, but it's a great first step.

   - driver core const api changes.

     This reached across all bus types, and there are some fix-ups for
     some not-common bus types that linux-next and 0-day testing shook
     out.

     This work is being done to help make the rust bindings more safe,
     as well as the C code, moving toward the end-goal of allowing us to
     put driver structures into read-only memory. We aren't there yet,
     but are getting closer.

   - minor devres cleanups and fixes found by code inspection

   - arch_topology minor changes

   - other minor driver core cleanups

  All of these have been in linux-next for a very long time with no
  reported problems"

* tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
  ARM: sa1100: make match function take a const pointer
  sysfs/cpu: Make crash_hotplug attribute world-readable
  dio: Have dio_bus_match() callback take a const *
  zorro: make match function take a const pointer
  driver core: module: make module_[add|remove]_driver take a const *
  driver core: make driver_find_device() take a const *
  driver core: make driver_[create|remove]_file take a const *
  firmware_loader: fix soundness issue in `request_internal`
  firmware_loader: annotate doctests as `no_run`
  devres: Correct code style for functions that return a pointer type
  devres: Initialize an uninitialized struct member
  devres: Fix memory leakage caused by driver API devm_free_percpu()
  devres: Fix devm_krealloc() wasting memory
  driver core: platform: Switch to use kmemdup_array()
  driver core: have match() callback in struct bus_type take a const *
  MAINTAINERS: add Rust device abstractions to DRIVER CORE
  device: rust: improve safety comments
  MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer
  MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER
  firmware: rust: improve safety comments
  ...

Pull watchdog updates from Wim Van Sebroeck:

 - make watchdog_class const

 - rework of the rzg2l_wdt driver

 - other small fixes and improvements

* tag 'linux-watchdog-6.11-rc1' of git://www.linux-watchdog.org/linux-watchdog:
  dt-bindings: watchdog: dlg,da9062-watchdog: Drop blank space
  watchdog: rzn1: Convert comma to semicolon
  watchdog: lenovo_se10_wdt: Convert comma to semicolon
  dt-bindings: watchdog: renesas,wdt: Document RZ/G3S support
  watchdog: rzg2l_wdt: Add suspend/resume support
  watchdog: rzg2l_wdt: Rely on the reset driver for doing proper reset
  watchdog: rzg2l_wdt: Remove comparison with zero
  watchdog: rzg2l_wdt: Remove reset de-assert from probe
  watchdog: rzg2l_wdt: Check return status of pm_runtime_put()
  watchdog: rzg2l_wdt: Use pm_runtime_resume_and_get()
  watchdog: rzg2l_wdt: Make the driver depend on PM
  watchdog: rzg2l_wdt: Restrict the driver to ARCH_RZG2L and ARCH_R9A09G011
  watchdog: imx7ulp_wdt: keep already running watchdog enabled
  watchdog: starfive: Add missing clk_disable_unprepare()
  watchdog: Make watchdog_class const

Pull dma-mapping fix from Christoph Hellwig:

 - fix the order of actions in dmam_free_coherent (Lance Richardson)

* tag 'dma-mapping-6.11-2024-07-24' of git://git.infradead.org/users/hch/dma-mapping:
  dma: fix call order in dmam_free_coherent

Dongli Zhang says:

====================
tap/tun: harden by dropping short frame

This is to harden all of tap/tun to avoid any short frame smaller than the
Ethernet header (ETH_HLEN).

While the xen-netback already rejects short frame smaller than ETH_HLEN ...

 914 static void xenvif_tx_build_gops(struct xenvif_queue *queue,
 915                                      int budget,
 916                                      unsigned *copy_ops,
 917                                      unsigned *map_ops)
 918 {
... ...
1007                 if (unlikely(txreq.size < ETH_HLEN)) {
1008                         netdev_dbg(queue->vif->dev,
1009                                    "Bad packet size: %d\n", txreq.size);
1010                         xenvif_tx_err(queue, &txreq, extra_count, idx);
1011                         break;
1012                 }

... the short frame may not be dropped by vhost-net/tap/tun.

This fixes CVE-2024-41090 and CVE-2024-41091.
====================

Link: https://patch.msgid.link/20240724170452.16837-1-dongli.zhang@oracle.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The cited commit missed to check against the validity of the frame length
in the tun_xdp_one() path, which could cause a corrupted skb to be sent
downstack. Even before the skb is transmitted, the
tun_xdp_one-->eth_type_trans() may access the Ethernet header although it
can be less than ETH_HLEN. Once transmitted, this could either cause
out-of-bound access beyond the actual length, or confuse the underlayer
with incorrect or inconsistent header length in the skb metadata.

In the alternative path, tun_get_user() already prohibits short frame which
has the length less than Ethernet header size from being transmitted for
IFF_TAP.

This is to drop any frame shorter than the Ethernet header size just like
how tun_get_user() does.

CVE: CVE-2024-41091
Inspired-by: https://lore.kernel.org/netdev/1717026141-25716-1-git-send-email-si-wei.liu@oracle.com/
Fixes: 043d222f ("tuntap: accept an array of XDP buffs through sendmsg()")
Cc: stable@vger.kernel.org
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Link: https://patch.msgid.link/20240724170452.16837-3-dongli.zhang@oracle.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The cited commit missed to check against the validity of the frame length
in the tap_get_user_xdp() path, which could cause a corrupted skb to be
sent downstack. Even before the skb is transmitted, the
tap_get_user_xdp()-->skb_set_network_header() may assume the size is more
than ETH_HLEN. Once transmitted, this could either cause out-of-bound
access beyond the actual length, or confuse the underlayer with incorrect
or inconsistent header length in the skb metadata.

In the alternative path, tap_get_user() already prohibits short frame which
has the length less than Ethernet header size from being transmitted.

This is to drop any frame shorter than the Ethernet header size just like
how tap_get_user() does.

CVE: CVE-2024-41090
Link: https://lore.kernel.org/netdev/1717026141-25716-1-git-send-email-si-wei.liu@oracle.com/
Fixes: 0efac277 ("tap: accept an array of XDP buffs through sendmsg()")
Cc: stable@vger.kernel.org
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Link: https://patch.msgid.link/20240724170452.16837-2-dongli.zhang@oracle.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Don't dereference *sp after calling dev_kfree_skb(*sp).

Fixes: af69fb3a ("Add mISDN HFC multiport driver")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/8be65f5a-c2dd-4ba0-8a10-bfe5980b8cfb@stanley.mountainSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The NIC requires each TSO segment to not span more than 10
descriptors. NIC further requires each descriptor to not exceed
16KB - 1 (GVE_TX_MAX_BUF_SIZE_DQO).

The descriptors for an skb are generated by
gve_tx_add_skb_no_copy_dqo() for DQO RDA queue format.
gve_tx_add_skb_no_copy_dqo() loops through each skb frag and
generates a descriptor for the entire frag if the frag size is
not greater than GVE_TX_MAX_BUF_SIZE_DQO. If the frag size is
greater than GVE_TX_MAX_BUF_SIZE_DQO, it is split into descriptor(s)
of size GVE_TX_MAX_BUF_SIZE_DQO and a descriptor is generated for
the remainder (frag size % GVE_TX_MAX_BUF_SIZE_DQO).

gve_can_send_tso() checks if the descriptors thus generated for an
skb would meet the requirement that each TSO-segment not span more
than 10 descriptors. However, the current code misses an edge case
when a TSO segment spans multiple descriptors within a large frag.
This change fixes the edge case.

gve_can_send_tso() relies on the assumption that max gso size (9728)
is less than GVE_TX_MAX_BUF_SIZE_DQO and therefore within an skb
fragment a TSO segment can never span more than 2 descriptors.

Fixes: a57e5de4 ("gve: DQO: Add TX path")
Signed-off-by: Praveen Kaligineedi <pkaligineedi@google.com>
Signed-off-by: Bailey Forrest <bcf@google.com>
Reviewed-by: Jeroen de Borst <jeroendb@google.com>
Cc: stable@vger.kernel.org
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20240724143431.3343722-1-pkaligineedi@google.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

When the netdev_rx_queue_restart() restarts queues, the bnxt_en driver
updates(creates and deletes) a page_pool.
But it doesn't update xdp_rxq_info, so the xdp_rxq_info is still
connected to an old page_pool.
So, bnxt_rx_ring_info->page_pool indicates a new page_pool, but
bnxt_rx_ring_info->xdp_rxq is still connected to an old page_pool.

An old page_pool is no longer used so it is supposed to be
deleted by page_pool_destroy() but it isn't.
Because the xdp_rxq_info is holding the reference count for it and the
xdp_rxq_info is not updated, an old page_pool will not be deleted in
the queue restart logic.

Before restarting 1 queue:
./tools/net/ynl/samples/page-pool
enp10s0f1np1[6] page pools: 4 (zombies: 0)
	refs: 8192 bytes: 33554432 (refs: 0 bytes: 0)
	recycling: 0.0% (alloc: 128:8048 recycle: 0:0)

After restarting 1 queue:
./tools/net/ynl/samples/page-pool
enp10s0f1np1[6] page pools: 5 (zombies: 0)
	refs: 10240 bytes: 41943040 (refs: 0 bytes: 0)
	recycling: 20.0% (alloc: 160:10080 recycle: 1920:128)

Before restarting queues, an interface has 4 page_pools.
After restarting one queue, an interface has 5 page_pools, but it
should be 4, not 5.
The reason is that queue restarting logic creates a new page_pool and
an old page_pool is not deleted due to the absence of an update of
xdp_rxq_info logic.

Fixes: 2d694c27 ("bnxt_en: implement netdev_queue_mgmt_ops")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: David Wei <dw@davidwei.uk>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Link: https://patch.msgid.link/20240721053554.1233549-1-ap420073@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Daniel Borkmann says:

====================
pull-request: bpf 2024-07-25

We've added 14 non-merge commits during the last 8 day(s) which contain
a total of 19 files changed, 177 insertions(+), 70 deletions(-).

The main changes are:

1) Fix af_unix to disable MSG_OOB handling for sockets in BPF sockmap and
   BPF sockhash. Also add test coverage for this case, from Michal Luczaj.

2) Fix a segmentation issue when downgrading gso_size in the BPF helper
   bpf_skb_adjust_room(), from Fred Li.

3) Fix a compiler warning in resolve_btfids due to a missing type cast,
   from Liwei Song.

4) Fix stack allocation for arm64 to align the stack pointer at a 16 byte
   boundary in the fexit_sleep BPF selftest, from Puranjay Mohan.

5) Fix a xsk regression to require a flag when actuating tx_metadata_len,
   from Stanislav Fomichev.

6) Fix function prototype BTF dumping in libbpf for prototypes that have
   no input arguments, from Andrii Nakryiko.

7) Fix stacktrace symbol resolution in perf script for BPF programs
   containing subprograms, from Hou Tao.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Add XDP_UMEM_TX_METADATA_LEN to XSK TX metadata test
  xsk: Require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len
  bpf: Fix a segment issue when downgrading gso_size
  tools/resolve_btfids: Fix comparison of distinct pointer types warning in resolve_btfids
  bpf, events: Use prog to emit ksymbol event for main program
  selftests/bpf: Test sockmap redirect for AF_UNIX MSG_OOB
  selftests/bpf: Parametrize AF_UNIX redir functions to accept send() flags
  selftests/bpf: Support SOCK_STREAM in unix_inet_redir_to_connected()
  af_unix: Disable MSG_OOB handling for sockets in sockmap/sockhash
  bpftool: Fix typo in usage help
  libbpf: Fix no-args func prototype BTF dumping syntax
  MAINTAINERS: Update powerpc BPF JIT maintainers
  MAINTAINERS: Update email address of Naveen
  selftests/bpf: fexit_sleep: Fix stack allocation for arm64
====================

Link: https://patch.msgid.link/20240725114312.32197-1-daniel@iogearbox.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>