This patch is to make libbpf able to handle the following extern
kernel function declaration and do the needed relocations before
loading the bpf program to the kernel.

extern int foo(struct sock *) __attribute__((section(".ksyms")))

In the collect extern phase, needed changes is made to
bpf_object__collect_externs() and find_extern_btf_id() to collect
extern function in ".ksyms" section.  The func in the BTF datasec also
needs to be replaced by an int var.  The idea is similar to the existing
handling in extern var.  In case the BTF may not have a var, a dummy ksym
var is added at the beginning of bpf_object__collect_externs()
if there is func under ksyms datasec.  It will also change the
func linkage from extern to global which the kernel can support.
It also assigns a param name if it does not have one.

In the collect relo phase, it will record the kernel function
call as RELO_EXTERN_FUNC.

bpf_object__resolve_ksym_func_btf_id() is added to find the func
btf_id of the running kernel.

During actual relocation, it will patch the BPF_CALL instruction with
src_reg = BPF_PSEUDO_FUNC_CALL and insn->imm set to the running
kernel func's btf_id.

The required LLVM patch: https://reviews.llvm.org/D93563Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015234.1548923-1-kafai@fb.com

This patch records the extern sym relocs first before recording
subprog relocs.  The later patch will have relocs for extern
kernel function call which is also using BPF_JMP | BPF_CALL.
It will be easier to handle the extern symbols first in
the later patch.

is_call_insn() helper is added.  The existing is_ldimm64() helper
is renamed to is_ldimm64_insn() for consistency.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015227.1548623-1-kafai@fb.com

This patch renames RELO_EXTERN to RELO_EXTERN_VAR.
It is to avoid the confusion with a later patch adding
RELO_EXTERN_FUNC.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015221.1547722-1-kafai@fb.com

This patch refactors code, that finds kernel btf_id by kind
and symbol name, to a new function find_ksym_btf_id().

It also adds a new helper __btf_kind_str() to return
a string by the numeric kind value.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015214.1547069-1-kafai@fb.com

This patch refactors most of the logic from
bpf_object__resolve_ksyms_btf_id() into a new function
bpf_object__resolve_ksym_var_btf_id().
It is to get ready for a later patch adding
bpf_object__resolve_ksym_func_btf_id() which resolves
a kernel function to the running kernel btf_id.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015207.1546749-1-kafai@fb.com

This patch puts some tcp cong helper functions, tcp_slow_start()
and tcp_cong_avoid_ai(), into the allowlist for the bpf-tcp-cc
program.

A few tcp cc implementation functions are also put into the
allowlist.  A potential use case is the bpf-tcp-cc implementation
may only want to override a subset of a tcp_congestion_ops.  For others,
the bpf-tcp-cc can directly call the kernel counter parts instead of
re-implementing (or copy-and-pasting) them to the bpf program.

They will only be available to the bpf-tcp-cc typed program.
The allowlist functions are not bounded to a fixed ABI contract.
When any of them has changed, the bpf-tcp-cc program has to be changed
like any in-tree/out-of-tree kernel tcp-cc implementations do also.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015201.1546345-1-kafai@fb.com

The cubic functions in tcp_cubic.c are using the bictcp prefix as
in tcp_bic.c.  This patch gives it the proper name cubictcp
because the later patch will allow the bpf prog to directly
call the cubictcp implementation.  Renaming them will avoid
the name collision when trying to find the intended
one to call during bpf prog load time.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015155.1545532-1-kafai@fb.com

This patch adds kernel function call support to the x86-32 bpf jit.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015149.1545267-1-kafai@fb.com

This patch adds support to BPF verifier to allow bpf program calling
kernel function directly.

The use case included in this set is to allow bpf-tcp-cc to directly
call some tcp-cc helper functions (e.g. "tcp_cong_avoid_ai()").  Those
functions have already been used by some kernel tcp-cc implementations.

This set will also allow the bpf-tcp-cc program to directly call the
kernel tcp-cc implementation,  For example, a bpf_dctcp may only want to
implement its own dctcp_cwnd_event() and reuse other dctcp_*() directly
from the kernel tcp_dctcp.c instead of reimplementing (or
copy-and-pasting) them.

The tcp-cc kernel functions mentioned above will be white listed
for the struct_ops bpf-tcp-cc programs to use in a later patch.
The white listed functions are not bounded to a fixed ABI contract.
Those functions have already been used by the existing kernel tcp-cc.
If any of them has changed, both in-tree and out-of-tree kernel tcp-cc
implementations have to be changed.  The same goes for the struct_ops
bpf-tcp-cc programs which have to be adjusted accordingly.

This patch is to make the required changes in the bpf verifier.

First change is in btf.c, it adds a case in "btf_check_func_arg_match()".
When the passed in "btf->kernel_btf == true", it means matching the
verifier regs' states with a kernel function.  This will handle the
PTR_TO_BTF_ID reg.  It also maps PTR_TO_SOCK_COMMON, PTR_TO_SOCKET,
and PTR_TO_TCP_SOCK to its kernel's btf_id.

In the later libbpf patch, the insn calling a kernel function will
look like:

insn->code == (BPF_JMP | BPF_CALL)
insn->src_reg == BPF_PSEUDO_KFUNC_CALL /* <- new in this patch */
insn->imm == func_btf_id /* btf_id of the running kernel */

[ For the future calling function-in-kernel-module support, an array
  of module btf_fds can be passed at the load time and insn->off
  can be used to index into this array. ]

At the early stage of verifier, the verifier will collect all kernel
function calls into "struct bpf_kfunc_desc".  Those
descriptors are stored in "prog->aux->kfunc_tab" and will
be available to the JIT.  Since this "add" operation is similar
to the current "add_subprog()" and looking for the same insn->code,
they are done together in the new "add_subprog_and_kfunc()".

In the "do_check()" stage, the new "check_kfunc_call()" is added
to verify the kernel function call instruction:
1. Ensure the kernel function can be used by a particular BPF_PROG_TYPE.
   A new bpf_verifier_ops "check_kfunc_call" is added to do that.
   The bpf-tcp-cc struct_ops program will implement this function in
   a later patch.
2. Call "btf_check_kfunc_args_match()" to ensure the regs can be
   used as the args of a kernel function.
3. Mark the regs' type, subreg_def, and zext_dst.

At the later do_misc_fixups() stage, the new fixup_kfunc_call()
will replace the insn->imm with the function address (relative
to __bpf_call_base).  If needed, the jit can find the btf_func_model
by calling the new bpf_jit_find_kfunc_model(prog, insn).
With the imm set to the function address, "bpftool prog dump xlated"
will be able to display the kernel function calls the same way as
it displays other bpf helper calls.

gpl_compatible program is required to call kernel function.

This feature currently requires JIT.

The verifier selftests are adjusted because of the changes in
the verbose log in add_subprog_and_kfunc().
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015142.1544736-1-kafai@fb.com

This patch moved the subprog specific logic from
btf_check_func_arg_match() to the new btf_check_subprog_arg_match().
The core logic is left in btf_check_func_arg_match() which
will be reused later to check the kernel function call.

The "if (!btf_type_is_ptr(t))" is checked first to improve the
indentation which will be useful for a later patch.

Some of the "btf_kind_str[]" usages is replaced with the shortcut
"btf_type_str(t)".
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015136.1544504-1-kafai@fb.com

This patch simplifies the linfo freeing logic by combining
"bpf_prog_free_jited_linfo()" and "bpf_prog_free_unused_jited_linfo()"
into the new "bpf_prog_jit_attempt_done()".
It is a prep work for the kernel function call support.  In a later
patch, freeing the kernel function call descriptors will also
be done in the "bpf_prog_jit_attempt_done()".

"bpf_prog_free_linfo()" is removed since it is only called by
"__bpf_prog_put_noref()".  The kvfree() are directly called
instead.

It also takes this chance to s/kcalloc/kvcalloc/ for the jited_linfo
allocation.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015130.1544323-1-kafai@fb.com

Ensure that BPF static linker preserves all DATASEC BTF types, even if some of
them might not have any variable information at all. This may happen if the
compiler promotes local initialized variable contents into .rodata section and
there are no global or static functions in the program.

For example,

  $ cat t.c
  struct t { char a; char b; char c; };
  void bar(struct t*);
  void find() {
     struct t tmp = {1, 2, 3};
     bar(&tmp);
  }

  $ clang -target bpf -O2 -g -S t.c
         .long   104                             # BTF_KIND_DATASEC(id = 8)
         .long   251658240                       # 0xf000000
         .long   0

         .ascii  ".rodata"                       # string offset=104

  $ clang -target bpf -O2 -g -c t.c
  $ readelf -S t.o | grep data
     [ 4] .rodata           PROGBITS         0000000000000000  00000090

Fixes: 8fd27bf6 ("libbpf: Add BPF static linker BTF and BTF.ext support")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210326043036.3081011-1-andrii@kernel.org

struct sock has been declared twice, therefore remove the duplicate.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210325070602.858024-1-wanjiabing@vivo.com

The header <linux/version.h> is useless in sampleip_kern.c
and trace_event_kern.c, remove it.
Signed-off-by: Lu Wei <luwei32@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210324083147.149278-1-luwei32@huawei.com

Unfortunately some distros don't have their kernel version defined
accurately in <linux/version.h> due to different long term support
reasons.

It is important to have a way to override the bpf kern_version
attribute during runtime: some old kernels might still check for
kern_version attribute during bpf_prog_load().
Signed-off-by: Rafael David Tinoco <rafaeldtinoco@ubuntu.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210323040952.2118241-1-rafaeldtinoco@ubuntu.com

Pedro Tammela says:

====================

The patch itself is straightforward thanks to the infrastructure that is
already in-place.

The tests follows the other '*_map_batch_ops' tests with minor tweaks.

v1 -> v2:
Fixes for checkpatch warnings
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Uses the already existing infrastructure for testing batched ops.
The testing code is essentially the same, with minor tweaks for this use
case.
Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210323025058.315763-3-pctammela@gmail.com

Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210323025058.315763-2-pctammela@gmail.com

The current implementation uses the CHECK_FAIL macro which does not
provide useful error messages when the script fails. Use the CHECK macro
instead and provide more descriptive messages to aid debugging.
Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210322170720.2926715-1-kpsingh@kernel.org

Jiri Olsa reported a bug ([1]) in kernel where cgroup local
storage pointer may be NULL in bpf_get_local_storage() helper.
There are two issues uncovered by this bug:
  (1). kprobe or tracepoint prog incorrectly sets cgroup local storage
       before prog run,
  (2). due to change from preempt_disable to migrate_disable,
       preemption is possible and percpu storage might be overwritten
       by other tasks.

This issue (1) is fixed in [2]. This patch tried to address issue (2).
The following shows how things can go wrong:
  task 1:   bpf_cgroup_storage_set() for percpu local storage
         preemption happens
  task 2:   bpf_cgroup_storage_set() for percpu local storage
         preemption happens
  task 1:   run bpf program

task 1 will effectively use the percpu local storage setting by task 2
which will be either NULL or incorrect ones.

Instead of just one common local storage per cpu, this patch fixed
the issue by permitting 8 local storages per cpu and each local
storage is identified by a task_struct pointer. This way, we
allow at most 8 nested preemption between bpf_cgroup_storage_set()
and bpf_cgroup_storage_unset(). The percpu local storage slot
is released (calling bpf_cgroup_storage_unset()) by the same task
after bpf program finished running.
bpf_test_run() is also fixed to use the new bpf_cgroup_storage_set()
interface.

The patch is tested on top of [2] with reproducer in [1].
Without this patch, kernel will emit error in 2-3 minutes.
With this patch, after one hour, still no error.

 [1] https://lore.kernel.org/bpf/CAKH8qBuXCfUz=w8L+Fj74OaUpbosO29niYwTki7e3Ag044_aww@mail.gmail.com/T
 [2] https://lore.kernel.org/bpf/20210309185028.3763817-1-yhs@fb.comSigned-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Roman Gushchin <guro@fb.com>
Link: https://lore.kernel.org/bpf/20210323055146.3334476-1-yhs@fb.com

bpf_program__get_type() and bpf_program__get_expected_attach_type() shouldn't
modify given bpf_program, so mark input parameter as const struct bpf_program.
This eliminates unnecessary compilation warnings or explicit casts in user
programs.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210324172941.2609884-1-andrii@kernel.org

Trivial fix.
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210318202223.164873-8-ribalda@chromium.org

Remove PTR_TO_MAP_KEY for the time being from being sanitized on pointer ALU
through sanitize_ptr_alu() mainly for 3 reasons:

  1) It's currently unused and not available from unprivileged. However that by
     itself is not yet a strong reason to drop the code.

  2) Commit 69c087ba ("bpf: Add bpf_for_each_map_elem() helper") implemented
     the sanitation not fully correct in that unlike stack or map_value pointer
     it doesn't probe whether the access to the map key /after/ the simulated ALU
     operation is still in bounds. This means that the generated mask can truncate
     the offset in the non-speculative domain whereas it should only truncate in
     the speculative domain. The verifier should instead reject such program as
     we do for other types.

  3) Given the recent fixes from f232326f ("bpf: Prohibit alu ops for pointer
     types not defining ptr_limit"), 10d2bb2e ("bpf: Fix off-by-one for area
     size in creating mask to left"), b5871dca ("bpf: Simplify alu_limit masking
     for pointer arithmetic") as well as 1b1597e6 ("bpf: Add sanity check for
     upper ptr_limit") the code changed quite a bit and the merge in efd13b71
     broke the PTR_TO_MAP_KEY case due to an incorrect merge conflict.

Remove the relevant pieces for the time being and we can rework the PTR_TO_MAP_KEY
case once everything settles.

Fixes: efd13b71 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net")
Fixes: 69c087ba ("bpf: Add bpf_for_each_map_elem() helper")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-03-24

The following pull-request contains BPF updates for your *net-next* tree.

We've added 37 non-merge commits during the last 15 day(s) which contain
a total of 65 files changed, 3200 insertions(+), 738 deletions(-).

The main changes are:

1) Static linking of multiple BPF ELF files, from Andrii.

2) Move drop error path to devmap for XDP_REDIRECT, from Lorenzo.

3) Spelling fixes from various folks.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

Merge misc fixes from Andrew Morton:
 "14 patches.

  Subsystems affected by this patch series: mm (hugetlb, kasan, gup,
  selftests, z3fold, kfence, memblock, and highmem), squashfs, ia64,
  gcov, and mailmap"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mailmap: update Andrey Konovalov's email address
  mm/highmem: fix CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
  mm: memblock: fix section mismatch warning again
  kfence: make compatible with kmemleak
  gcov: fix clang-11+ support
  ia64: fix format strings for err_inject
  ia64: mca: allocate early mca with GFP_ATOMIC
  squashfs: fix xattr id and id lookup sanity checks
  squashfs: fix inode lookup sanity checks
  z3fold: prevent reclaim/free race for headless pages
  selftests/vm: fix out-of-tree build
  mm/mmu_notifiers: ensure range_end() is paired with range_start()
  kasan: fix per-page tags for non-page_alloc pages
  hugetlb_cgroup: fix imbalanced css_get and css_put pair for shared mappings

Pull rdma fixes from Jason Gunthorpe:
 "Not much going on, just some small bug fixes:

   - Typo causing a regression in mlx5 devx

   - Regression in the recent hns rework causing the HW to get out of
     sync

   - Long-standing cxgb4 adaptor crash when destroying cm ids"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/cxgb4: Fix adapter LE hash errors while destroying ipv6 listening server
  RDMA/hns: Fix bug during CMDQ initialization
  RDMA/mlx5: Fix typo in destroy_mkey inbox

Pull mfs fix from Lee Jones:
 "Unconstify editable placeholder structures"

* tag 'mfd-fixes-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd:
  mfd: intel_quark_i2c_gpio: Revert "Constify static struct resources"

Pull arm64 fixes from Will Deacon:
 "Minor fixes all over, ranging from typos to tests to errata
  workarounds:

   - Fix possible memory hotplug failure with KASLR

   - Fix FFR value in SVE kselftest

   - Fix backtraces reported in /proc/$pid/stack

   - Disable broken CnP implementation on NVIDIA Carmel

   - Typo fixes and ACPI documentation clarification

   - Fix some W=1 warnings"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: kernel: disable CNP on Carmel
  arm64/process.c: fix Wmissing-prototypes build warnings
  kselftest/arm64: sve: Do not use non-canonical FFR register value
  arm64: mm: correct the inside linear map range during hotplug check
  arm64: kdump: update ppos when reading elfcorehdr
  arm64: cpuinfo: Fix a typo
  Documentation: arm64/acpi : clarify arm64 support of IBFT
  arm64: stacktrace: don't trace arch_stack_walk()
  arm64: csum: cast to the proper type

Redirect my older email addresses in the git logs.
Signed-off-by: Chris Chiu <chris.chiu@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use my personal email, the @google.com one will stop functioning soon.

Link: https://lkml.kernel.org/r/ead0e9c32a2f70e0bde6f63b3b9470e0ef13d2ee.1616107969.git.andreyknvl@google.comSigned-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The kernel test robot found that __kmap_local_sched_out() was not
correctly skipping the guard pages when DEBUG_KMAP_LOCAL_FORCE_MAP was
set.[1] This was due to DEBUG_HIGHMEM check being used.

Change the configuration check to be correct.

[1] https://lore.kernel.org/lkml/20210304083825.GB17830@xsang-OptiPlex-9020/

Link: https://lkml.kernel.org/r/20210318230657.1497881-1-ira.weiny@intel.com
Fixes: 0e91a0c6 ("mm/highmem: Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP")
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Oliver Sang <oliver.sang@intel.com>
Cc: Chaitanya Kulkarni <Chaitanya.Kulkarni@wdc.com>
Cc: David Sterba <dsterba@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 34dc2efb ("memblock: fix section mismatch warning") marked
memblock_bottom_up() and memblock_set_bottom_up() as __init, but they
could be referenced from non-init functions like
memblock_find_in_range_node() on architectures that enable
CONFIG_ARCH_KEEP_MEMBLOCK.

For such builds kernel test robot reports:

   WARNING: modpost: vmlinux.o(.text+0x74fea4): Section mismatch in reference from the function memblock_find_in_range_node() to the function .init.text:memblock_bottom_up()
   The function memblock_find_in_range_node() references the function __init memblock_bottom_up().
   This is often because memblock_find_in_range_node lacks a __init  annotation or the annotation of memblock_bottom_up is wrong.

Replace __init annotations with __init_memblock annotations so that the
appropriate section will be selected depending on
CONFIG_ARCH_KEEP_MEMBLOCK.

Link: https://lore.kernel.org/lkml/202103160133.UzhgY0wt-lkp@intel.com
Link: https://lkml.kernel.org/r/20210316171347.14084-1-rppt@kernel.org
Fixes: 34dc2efb ("memblock: fix section mismatch warning")
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Because memblock allocations are registered with kmemleak, the KFENCE
pool was seen by kmemleak as one large object.  Later allocations
through kfence_alloc() that were registered with kmemleak via
slab_post_alloc_hook() would then overlap and trigger a warning.
Therefore, once the pool is initialized, we can remove (free) it from
kmemleak again, since it should be treated as allocator-internal and be
seen as "free memory".

The second problem is that kmemleak is passed the rounded size, and not
the originally requested size, which is also the size of KFENCE objects.
To avoid kmemleak scanning past the end of an object and trigger a
KFENCE out-of-bounds error, fix the size if it is a KFENCE object.

For simplicity, to avoid a call to kfence_ksize() in
slab_post_alloc_hook() (and avoid new IS_ENABLED(CONFIG_DEBUG_KMEMLEAK)
guard), just call kfence_ksize() in mm/kmemleak.c:create_object().

Link: https://lkml.kernel.org/r/20210317084740.3099921-1-elver@google.comSigned-off-by: Marco Elver <elver@google.com>
Reported-by: Luis Henriques <lhenriques@suse.de>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Luis Henriques <lhenriques@suse.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

LLVM changed the expected function signatures for llvm_gcda_start_file()
and llvm_gcda_emit_function() in the clang-11 release.  Users of
clang-11 or newer may have noticed their kernels failing to boot due to
a panic when enabling CONFIG_GCOV_KERNEL=y +CONFIG_GCOV_PROFILE_ALL=y.
Fix up the function signatures so calling these functions doesn't panic
the kernel.

Link: https://reviews.llvm.org/rGcdd683b516d147925212724b09ec6fb792a40041
Link: https://reviews.llvm.org/rG13a633b438b6500ecad9e4f936ebadf3411d0f44
Link: https://lkml.kernel.org/r/20210312224132.3413602-2-ndesaulniers@google.comSigned-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Prasad Sodagudi <psodagud@quicinc.com>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Cc: <stable@vger.kernel.org>	[5.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix warning with %lx / u64 mismatch:

  arch/ia64/kernel/err_inject.c: In function 'show_resources':
  arch/ia64/kernel/err_inject.c:62:22: warning:
    format '%lx' expects argument of type 'long unsigned int',
    but argument 3 has type 'u64' {aka 'long long unsigned int'}
     62 |  return sprintf(buf, "%lx", name[cpu]);   \
        |                      ^~~~~~~

Link: https://lkml.kernel.org/r/20210313104312.1548232-1-slyfox@gentoo.orgSigned-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The sleep warning happens at early boot right at secondary CPU
activation bootup:

    smp: Bringing up secondary CPUs ...
    BUG: sleeping function called from invalid context at mm/page_alloc.c:4942
    in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
    CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.12.0-rc2-00007-g79e228d0b611-dirty #99
    ..
    Call Trace:
      show_stack+0x90/0xc0
      dump_stack+0x150/0x1c0
      ___might_sleep+0x1c0/0x2a0
      __might_sleep+0xa0/0x160
      __alloc_pages_nodemask+0x1a0/0x600
      alloc_page_interleave+0x30/0x1c0
      alloc_pages_current+0x2c0/0x340
      __get_free_pages+0x30/0xa0
      ia64_mca_cpu_init+0x2d0/0x3a0
      cpu_init+0x8b0/0x1440
      start_secondary+0x60/0x700
      start_ap+0x750/0x780
    Fixed BSP b0 value from CPU 1

As I understand interrupts are not enabled yet and system has a lot of
memory.  There is little chance to sleep and switch to GFP_ATOMIC should
be a no-op.

Link: https://lkml.kernel.org/r/20210315085045.204414-1-slyfox@gentoo.orgSigned-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The checks for maximum metadata block size is missing
SQUASHFS_BLOCK_OFFSET (the two byte length count).

Link: https://lkml.kernel.org/r/2069685113.2081245.1614583677427@webmail.123-reg.co.uk
Fixes: f37aa4c7 ("squashfs: add more sanity checks in id lookup")
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Sean Nyekjaer <sean@geanix.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When mouting a squashfs image created without inode compression it fails
with: "unable to read inode lookup table"

It turns out that the BLOCK_OFFSET is missing when checking the
SQUASHFS_METADATA_SIZE agaist the actual size.

Link: https://lkml.kernel.org/r/20210226092903.1473545-1-sean@geanix.com
Fixes: eabac19e ("squashfs: add more sanity checks in inode lookup")
Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Acked-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit ca0246bb ("z3fold: fix possible reclaim races") introduced
the PAGE_CLAIMED flag "to avoid racing on a z3fold 'headless' page
release." By atomically testing and setting the bit in each of
z3fold_free() and z3fold_reclaim_page(), a double-free was avoided.

However, commit dcf5aedb ("z3fold: stricter locking and more careful
reclaim") appears to have unintentionally broken this behavior by moving
the PAGE_CLAIMED check in z3fold_reclaim_page() to after the page lock
gets taken, which only happens for non-headless pages.  For headless
pages, the check is now skipped entirely and races can occur again.

I have observed such a race on my system:

    page:00000000ffbd76b7 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x165316
    flags: 0x2ffff0000000000()
    raw: 02ffff0000000000 ffffea0004535f48 ffff8881d553a170 0000000000000000
    raw: 0000000000000000 0000000000000011 00000000ffffffff 0000000000000000
    page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0)
    ------------[ cut here ]------------
    kernel BUG at include/linux/mm.h:707!
    invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
    CPU: 2 PID: 291928 Comm: kworker/2:0 Tainted: G    B             5.10.7-arch1-1-kasan #1
    Hardware name: Gigabyte Technology Co., Ltd. H97N-WIFI/H97N-WIFI, BIOS F9b 03/03/2016
    Workqueue: zswap-shrink shrink_worker
    RIP: 0010:__free_pages+0x10a/0x130
    Code: c1 e7 06 48 01 ef 45 85 e4 74 d1 44 89 e6 31 d2 41 83 ec 01 e8 e7 b0 ff ff eb da 48 c7 c6 e0 32 91 88 48 89 ef e8 a6 89 f8 ff <0f> 0b 4c 89 e7 e8 fc 79 07 00 e9 33 ff ff ff 48 89 ef e8 ff 79 07
    RSP: 0000:ffff88819a2ffb98 EFLAGS: 00010296
    RAX: 0000000000000000 RBX: ffffea000594c5a8 RCX: 0000000000000000
    RDX: 1ffffd4000b298b7 RSI: 0000000000000000 RDI: ffffea000594c5b8
    RBP: ffffea000594c580 R08: 000000000000003e R09: ffff8881d5520bbb
    R10: ffffed103aaa4177 R11: 0000000000000001 R12: ffffea000594c5b4
    R13: 0000000000000000 R14: ffff888165316000 R15: ffffea000594c588
    FS:  0000000000000000(0000) GS:ffff8881d5500000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007f7c8c3654d8 CR3: 0000000103f42004 CR4: 00000000001706e0
    Call Trace:
     z3fold_zpool_shrink+0x9b6/0x1240
     shrink_worker+0x35/0x90
     process_one_work+0x70c/0x1210
     worker_thread+0x539/0x1200
     kthread+0x330/0x400
     ret_from_fork+0x22/0x30
    Modules linked in: rfcomm ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter ccm algif_aead des_generic libdes ecb algif_skcipher cmac bnep md4 algif_hash af_alg vfat fat intel_rapl_msr intel_rapl_common x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel iwlmvm hid_logitech_hidpp kvm at24 mac80211 snd_hda_codec_realtek iTCO_wdt snd_hda_codec_generic intel_pmc_bxt snd_hda_codec_hdmi ledtrig_audio iTCO_vendor_support mei_wdt mei_hdcp snd_hda_intel snd_intel_dspcfg libarc4 soundwire_intel irqbypass iwlwifi soundwire_generic_allocation rapl soundwire_cadence intel_cstate snd_hda_codec intel_uncore btusb joydev mousedev snd_usb_audio pcspkr btrtl uvcvideo nouveau btbcm i2c_i801 btintel snd_hda_core videobuf2_vmalloc i2c_smbus snd_usbmidi_lib videobuf2_memops bluetooth snd_hwdep soundwire_bus snd_soc_rt5640 videobuf2_v4l2 cfg80211 snd_soc_rl6231 videobuf2_common snd_rawmidi lpc_ich alx videodev mdio snd_seq_device snd_soc_core mc ecdh_generic mxm_wmi mei_me
     hid_logitech_dj wmi snd_compress e1000e ac97_bus mei ttm rfkill snd_pcm_dmaengine ecc snd_pcm snd_timer snd soundcore mac_hid acpi_pad pkcs8_key_parser it87 hwmon_vid crypto_user fuse ip_tables x_tables ext4 crc32c_generic crc16 mbcache jbd2 dm_crypt cbc encrypted_keys trusted tpm rng_core usbhid dm_mod crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel crypto_simd cryptd glue_helper xhci_pci xhci_pci_renesas i915 video intel_gtt i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm agpgart
    ---[ end trace 126d646fc3dc0ad8 ]---

To fix the issue, re-add the earlier test and set in the case where we
have a headless page.

Link: https://lkml.kernel.org/r/c8106dbe6d8390b290cd1d7f873a2942e805349e.1615452048.git.tommyhebb@gmail.com
Fixes: dcf5aedb ("z3fold: stricter locking and more careful reclaim")
Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Reviewed-by: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Jongseok Kim <ks77sj@gmail.com>
Cc: Snild Dolkow <snild@sony.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>