linux-stable.git/kernel, branch v5.4.237

btf: fix resolving BTF_KIND_VAR after ARRAY, STRUCT, UNION, PTR

2023-03-17T07:32:51+00:00

[ Upstream commit 9b459804ff9973e173fabafba2a1319f771e85fa ]

btf_datasec_resolve contains a bug that causes the following BTF
to fail loading:

    [1] DATASEC a size=2 vlen=2
        type_id=4 offset=0 size=1
        type_id=7 offset=1 size=1
    [2] INT (anon) size=1 bits_offset=0 nr_bits=8 encoding=(none)
    [3] PTR (anon) type_id=2
    [4] VAR a type_id=3 linkage=0
    [5] INT (anon) size=1 bits_offset=0 nr_bits=8 encoding=(none)
    [6] TYPEDEF td type_id=5
    [7] VAR b type_id=6 linkage=0

This error message is printed during btf_check_all_types:

    [1] DATASEC a size=2 vlen=2
        type_id=7 offset=1 size=1 Invalid type

By tracing btf_*_resolve we can pinpoint the problem:

    btf_datasec_resolve(depth: 1, type_id: 1, mode: RESOLVE_TBD) = 0
        btf_var_resolve(depth: 2, type_id: 4, mode: RESOLVE_TBD) = 0
            btf_ptr_resolve(depth: 3, type_id: 3, mode: RESOLVE_PTR) = 0
        btf_var_resolve(depth: 2, type_id: 4, mode: RESOLVE_PTR) = 0
    btf_datasec_resolve(depth: 1, type_id: 1, mode: RESOLVE_PTR) = -22

The last invocation of btf_datasec_resolve should invoke btf_var_resolve
by means of env_stack_push, instead it returns EINVAL. The reason is that
env_stack_push is never executed for the second VAR.

    if (!env_type_is_resolve_sink(env, var_type) &&
        !env_type_is_resolved(env, var_type_id)) {
        env_stack_set_next_member(env, i + 1);
        return env_stack_push(env, var_type, var_type_id);
    }

env_type_is_resolve_sink() changes its behaviour based on resolve_mode.
For RESOLVE_PTR, we can simplify the if condition to the following:

    (btf_type_is_modifier() || btf_type_is_ptr) && !env_type_is_resolved()

Since we're dealing with a VAR the clause evaluates to false. This is
not sufficient to trigger the bug however. The log output and EINVAL
are only generated if btf_type_id_size() fails.

    if (!btf_type_id_size(btf, &type_id, &type_size)) {
        btf_verifier_log_vsi(env, v->t, vsi, "Invalid type");
        return -EINVAL;
    }

Most types are sized, so for example a VAR referring to an INT is not a
problem. The bug is only triggered if a VAR points at a modifier. Since
we skipped btf_var_resolve that modifier was also never resolved, which
means that btf_resolved_type_id returns 0 aka VOID for the modifier.
This in turn causes btf_type_id_size to return NULL, triggering EINVAL.

To summarise, the following conditions are necessary:

- VAR pointing at PTR, STRUCT, UNION or ARRAY
- Followed by a VAR pointing at TYPEDEF, VOLATILE, CONST, RESTRICT or
  TYPE_TAG

The fix is to reset resolve_mode to RESOLVE_TBD before attempting to
resolve a VAR from a DATASEC.

Fixes: 1dc92851849c ("bpf: kernel side support for BTF Var and DataSec")
Signed-off-by: Lorenz Bauer 
Link: https://lore.kernel.org/r/20230306112138.155352-2-lmb@isovalent.com
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin

irqdomain: Fix domain registration race

2023-03-17T07:32:49+00:00

[ Upstream commit 8932c32c3053accd50702b36e944ac2016cd103c ]

Hierarchical domains created using irq_domain_create_hierarchy() are
currently added to the domain list before having been fully initialised.

This specifically means that a racing allocation request might fail to
allocate irq data for the inner domains of a hierarchy in case the
parent domain pointer has not yet been set up.

Note that this is not really any issue for irqchip drivers that are
registered early (e.g. via IRQCHIP_DECLARE() or IRQCHIP_ACPI_DECLARE())
but could potentially cause trouble with drivers that are registered
later (e.g. modular drivers using IRQCHIP_PLATFORM_DRIVER_BEGIN(),
gpiochip drivers, etc.).

Fixes: afb7da83b9f4 ("irqdomain: Introduce helper function irq_domain_add_hierarchy()")
Cc: stable@vger.kernel.org      # 3.19
Signed-off-by: Marc Zyngier 
[ johan: add commit message ]
Signed-off-by: Johan Hovold 
Signed-off-by: Marc Zyngier 
Link: https://lore.kernel.org/r/20230213104302.17307-8-johan+linaro@kernel.org
Signed-off-by: Sasha Levin

irqdomain: Change the type of 'size' in __irq_domain_add() to be consistent

2023-03-17T07:32:49+00:00

[ Upstream commit 20c36ce2164f1774b487d443ece99b754bc6ad43 ]

The 'size' is used in struct_size(domain, revmap, size) and its input
parameter type is 'size_t'(unsigned int).
Changing the size to 'unsigned int' to make the type consistent.

Signed-off-by: Bixuan Cui 
Signed-off-by: Marc Zyngier 
Link: https://lore.kernel.org/r/20210916025203.44841-1-cuibixuan@huawei.com
Stable-dep-of: 8932c32c3053 ("irqdomain: Fix domain registration race")
Signed-off-by: Sasha Levin

kernel/fail_function: fix memory leak with using debugfs_lookup()

2023-03-11T15:44:15+00:00

[ Upstream commit 2bb3669f576559db273efe49e0e69f82450efbca ]

When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time.  To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.

Cc: Andrew Morton 
Reviewed-by: Yang Yingliang 
Link: https://lore.kernel.org/r/20230202151633.2310897-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

tracing: Add NULL checks for buffer in ring_buffer_free_read_page()

2023-03-11T15:44:13+00:00

[ Upstream commit 3e4272b9954094907f16861199728f14002fcaf6 ]

In a previous commit 7433632c9ff6, buffer, buffer->buffers and
buffer->buffers[cpu] in ring_buffer_wake_waiters() can be NULL,
and thus the related checks are added.

However, in the same call stack, these variables are also used in
ring_buffer_free_read_page():

tracing_buffers_release()
  ring_buffer_wake_waiters(iter->array_buffer->buffer)
    cpu_buffer = buffer->buffers[cpu] -> Add checks by previous commit
  ring_buffer_free_read_page(iter->array_buffer->buffer)
    cpu_buffer = buffer->buffers[cpu] -> No check

Thus, to avod possible null-pointer derefernces, the related checks
should be added.

These results are reported by a static tool designed by myself.

Link: https://lkml.kernel.org/r/20230113125501.760324-1-baijiaju1990@gmail.com

Reported-by: TOTE Robot 
Signed-off-by: Jia-Ju Bai 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Sasha Levin

irqdomain: Drop bogus fwspec-mapping error handling

2023-03-11T15:44:03+00:00

commit e3b7ab025e931accdc2c12acf9b75c6197f1c062 upstream.

In case a newly allocated IRQ ever ends up not having any associated
struct irq_data it would not even be possible to dispose the mapping.

Replace the bogus disposal with a WARN_ON().

This will also be used to fix a shared-interrupt mapping race, hence the
CC-stable tag.

Fixes: 1e2a7d78499e ("irqdomain: Don't set type when mapping an IRQ")
Cc: stable@vger.kernel.org      # 4.8
Tested-by: Hsin-Yi Wang 
Tested-by: Mark-PK Tsai 
Signed-off-by: Johan Hovold 
Signed-off-by: Marc Zyngier 
Link: https://lore.kernel.org/r/20230213104302.17307-4-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman

irqdomain: Fix disassociation race

2023-03-11T15:44:03+00:00

commit 3f883c38f5628f46b30bccf090faec054088e262 upstream.

The global irq_domain_mutex is held when mapping interrupts from
non-hierarchical domains but currently not when disposing them.

This specifically means that updates of the domain mapcount is racy
(currently only used for statistics in debugfs).

Make sure to hold the global irq_domain_mutex also when disposing
mappings from non-hierarchical domains.

Fixes: 9dc6be3d4193 ("genirq/irqdomain: Add map counter")
Cc: stable@vger.kernel.org      # 4.13
Tested-by: Hsin-Yi Wang 
Tested-by: Mark-PK Tsai 
Signed-off-by: Johan Hovold 
Signed-off-by: Marc Zyngier 
Link: https://lore.kernel.org/r/20230213104302.17307-3-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman

irqdomain: Fix association race

2023-03-11T15:44:02+00:00

commit b06730a571a9ff1ba5bd6b20bf9e50e5a12f1ec6 upstream.

The sanity check for an already mapped virq is done outside of the
irq_domain_mutex-protected section which means that an (unlikely) racing
association may not be detected.

Fix this by factoring out the association implementation, which will
also be used in a follow-on change to fix a shared-interrupt mapping
race.

Fixes: ddaf144c61da ("irqdomain: Refactor irq_domain_associate_many()")
Cc: stable@vger.kernel.org      # 3.11
Tested-by: Hsin-Yi Wang 
Tested-by: Mark-PK Tsai 
Signed-off-by: Johan Hovold 
Signed-off-by: Marc Zyngier 
Link: https://lore.kernel.org/r/20230213104302.17307-2-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman

x86/kprobes: Fix arch_check_optimized_kprobe check within optimized_kprobe range

2023-03-11T15:44:02+00:00

commit f1c97a1b4ef709e3f066f82e3ba3108c3b133ae6 upstream.

When arch_prepare_optimized_kprobe calculating jump destination address,
it copies original instructions from jmp-optimized kprobe (see
__recover_optprobed_insn), and calculated based on length of original
instruction.

arch_check_optimized_kprobe does not check KPROBE_FLAG_OPTIMATED when
checking whether jmp-optimized kprobe exists.
As a result, setup_detour_execution may jump to a range that has been
overwritten by jump destination address, resulting in an inval opcode error.

For example, assume that register two kprobes whose addresses are
 and  in "func" function.
The original code of "func" function is as follows:

   0xffffffff816cb5e9 <+9>:     push   %r12
   0xffffffff816cb5eb <+11>:    xor    %r12d,%r12d
   0xffffffff816cb5ee <+14>:    test   %rdi,%rdi
   0xffffffff816cb5f1 <+17>:    setne  %r12b
   0xffffffff816cb5f5 <+21>:    push   %rbp

1.Register the kprobe for , assume that is kp1, corresponding optimized_kprobe is op1.
  After the optimization, "func" code changes to:

   0xffffffff816cc079 <+9>:     push   %r12
   0xffffffff816cc07b <+11>:    jmp    0xffffffffa0210000
   0xffffffff816cc080 <+16>:    incl   0xf(%rcx)
   0xffffffff816cc083 <+19>:    xchg   %eax,%ebp
   0xffffffff816cc084 <+20>:    (bad)
   0xffffffff816cc085 <+21>:    push   %rbp

Now op1->flags == KPROBE_FLAG_OPTIMATED;

2. Register the kprobe for , assume that is kp2, corresponding optimized_kprobe is op2.

register_kprobe(kp2)
  register_aggr_kprobe
    alloc_aggr_kprobe
      __prepare_optimized_kprobe
        arch_prepare_optimized_kprobe
          __recover_optprobed_insn    // copy original bytes from kp1->optinsn.copied_insn,
                                      // jump address = 

3. disable kp1:

disable_kprobe(kp1)
  __disable_kprobe
    ...
    if (p == orig_p || aggr_kprobe_disabled(orig_p)) {
      ret = disarm_kprobe(orig_p, true)       // add op1 in unoptimizing_list, not unoptimized
      orig_p->flags |= KPROBE_FLAG_DISABLED;  // op1->flags ==  KPROBE_FLAG_OPTIMATED | KPROBE_FLAG_DISABLED
    ...

4. unregister kp2
__unregister_kprobe_top
  ...
  if (!kprobe_disabled(ap) && !kprobes_all_disarmed) {
    optimize_kprobe(op)
      ...
      if (arch_check_optimized_kprobe(op) < 0) // because op1 has KPROBE_FLAG_DISABLED, here not return
        return;
      p->kp.flags |= KPROBE_FLAG_OPTIMIZED;   //  now op2 has KPROBE_FLAG_OPTIMIZED
  }

"func" code now is:

   0xffffffff816cc079 <+9>:     int3
   0xffffffff816cc07a <+10>:    push   %rsp
   0xffffffff816cc07b <+11>:    jmp    0xffffffffa0210000
   0xffffffff816cc080 <+16>:    incl   0xf(%rcx)
   0xffffffff816cc083 <+19>:    xchg   %eax,%ebp
   0xffffffff816cc084 <+20>:    (bad)
   0xffffffff816cc085 <+21>:    push   %rbp

5. if call "func", int3 handler call setup_detour_execution:

  if (p->flags & KPROBE_FLAG_OPTIMIZED) {
    ...
    regs->ip = (unsigned long)op->optinsn.insn + TMPL_END_IDX;
    ...
  }

The code for the destination address is

   0xffffffffa021072c:  push   %r12
   0xffffffffa021072e:  xor    %r12d,%r12d
   0xffffffffa0210731:  jmp    0xffffffff816cb5ee 

However,  is not a valid start instruction address. As a result, an error occurs.

Link: https://lore.kernel.org/all/20230216034247.32348-3-yangjihong1@huawei.com/

Fixes: f66c0447cca1 ("kprobes: Set unoptimized flag after unoptimizing code")
Signed-off-by: Yang Jihong 
Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu (Google) 
Signed-off-by: Masami Hiramatsu (Google) 
Signed-off-by: Greg Kroah-Hartman

x86/kprobes: Fix __recover_optprobed_insn check optimizing logic

2023-03-11T15:44:01+00:00

commit 868a6fc0ca2407622d2833adefe1c4d284766c4c upstream.

Since the following commit:

  commit f66c0447cca1 ("kprobes: Set unoptimized flag after unoptimizing code")

modified the update timing of the KPROBE_FLAG_OPTIMIZED, a optimized_kprobe
may be in the optimizing or unoptimizing state when op.kp->flags
has KPROBE_FLAG_OPTIMIZED and op->list is not empty.

The __recover_optprobed_insn check logic is incorrect, a kprobe in the
unoptimizing state may be incorrectly determined as unoptimizing.
As a result, incorrect instructions are copied.

The optprobe_queued_unopt function needs to be exported for invoking in
arch directory.

Link: https://lore.kernel.org/all/20230216034247.32348-2-yangjihong1@huawei.com/

Fixes: f66c0447cca1 ("kprobes: Set unoptimized flag after unoptimizing code")
Cc: stable@vger.kernel.org
Signed-off-by: Yang Jihong 
Acked-by: Masami Hiramatsu (Google) 
Signed-off-by: Masami Hiramatsu (Google) 
Signed-off-by: Greg Kroah-Hartman