linux-stable.git/include/linux, branch v6.2.15

mailbox: zynqmp: Fix typo in IPI documentation

2023-05-11T14:11:34+00:00

commit 79963fbfc233759bd8a43462f120d15a1bd4f4fa upstream.

Xilinx IPI message buffers allows 32-byte data transfer.
Fix documentation that says 12 bytes

Fixes: 4981b82ba2ff ("mailbox: ZynqMP IPI mailbox controller")
Signed-off-by: Tanmay Shah 
Acked-by: Michal Simek 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230311012407.1292118-4-tanmay.shah@amd.com
Signed-off-by: Mathieu Poirier 
Signed-off-by: Greg Kroah-Hartman

SUNRPC: remove the maximum number of retries in call_bind_status

2023-05-11T14:11:29+00:00

[ Upstream commit 691d0b782066a6eeeecbfceb7910a8f6184e6105 ]

Currently call_bind_status places a hard limit of 3 to the number of
retries on EACCES error. This limit was done to prevent NLM unlock
requests from being hang forever when the server keeps returning garbage.
However this change causes problem for cases when NLM service takes
longer than 9 seconds to register with the port mapper after a restart.

This patch removes this hard coded limit and let the RPC handles
the retry based on the standard hard/soft task semantics.

Fixes: 0b760113a3a1 ("NLM: Don't hang forever on NLM unlock requests")
Reported-by: Helen Chao 
Tested-by: Helen Chao 
Signed-off-by: Dai Ngo 
Reviewed-by: Jeff Layton 
Signed-off-by: Anna Schumaker 
Signed-off-by: Sasha Levin

RDMA/mlx5: Fix flow counter query via DEVX

2023-05-11T14:11:29+00:00

[ Upstream commit 3e358ea8614ddfbc59ca7a3f5dff5dde2b350b2c ]

Commit cited in "fixes" tag added bulk support for flow counters but it
didn't account that's also possible to query a counter using a non-base id
if the counter was allocated as bulk.

When a user performs a query, validate the flow counter id given in the
mailbox is inside the valid range taking bulk value into account.

Fixes: 208d70f562e5 ("IB/mlx5: Support flow counters offset for bulk counters")
Signed-off-by: Mark Bloch 
Reviewed-by: Maor Gottlieb 
Link: https://lore.kernel.org/r/79d7fbe291690128e44672418934256254d93115.1681377114.git.leon@kernel.org
Signed-off-by: Leon Romanovsky 
Signed-off-by: Sasha Levin

linux/vt_buffer.h: allow either builtin or modular for macros

2023-05-11T14:11:21+00:00

[ Upstream commit 2b76ffe81e32afd6d318dc4547e2ba8c46207b77 ]

Fix build errors on ARCH=alpha when CONFIG_MDA_CONSOLE=m.
This allows the ARCH macros to be the only ones defined.

In file included from ../drivers/video/console/mdacon.c:37:
../arch/alpha/include/asm/vga.h:17:40: error: expected identifier or '(' before 'volatile'
   17 | static inline void scr_writew(u16 val, volatile u16 *addr)
      |                                        ^~~~~~~~
../include/linux/vt_buffer.h:24:34: note: in definition of macro 'scr_writew'
   24 | #define scr_writew(val, addr) (*(addr) = (val))
      |                                  ^~~~
../include/linux/vt_buffer.h:24:40: error: expected ')' before '=' token
   24 | #define scr_writew(val, addr) (*(addr) = (val))
      |                                        ^
../arch/alpha/include/asm/vga.h:17:20: note: in expansion of macro 'scr_writew'
   17 | static inline void scr_writew(u16 val, volatile u16 *addr)
      |                    ^~~~~~~~~~
../arch/alpha/include/asm/vga.h:25:29: error: expected identifier or '(' before 'volatile'
   25 | static inline u16 scr_readw(volatile const u16 *addr)
      |                             ^~~~~~~~

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap 
Cc: Greg Kroah-Hartman 
Cc: Jiri Slaby 
Cc: dri-devel@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org
Link: https://lore.kernel.org/r/20230329021529.16188-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

netfilter: nf_tables: don't write table validation state without mutex

2023-05-11T14:11:19+00:00

[ Upstream commit 9a32e9850686599ed194ccdceb6cd3dd56b2d9b9 ]

The ->cleanup callback needs to be removed, this doesn't work anymore as
the transaction mutex is already released in the ->abort function.

Just do it after a successful validation pass, this either happens
from commit or abort phases where transaction mutex is held.

Fixes: f102d66b335a ("netfilter: nf_tables: use dedicated mutex to guard transactions")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

bpf: Add basic bpf_rb_{root,node} support

2023-05-11T14:11:11+00:00

[ Upstream commit 9c395c1b99bd23f74bc628fa000480c49593d17f ]

This patch adds special BPF_RB_{ROOT,NODE} btf_field_types similar to
BPF_LIST_{HEAD,NODE}, adds the necessary plumbing to detect the new
types, and adds bpf_rb_root_free function for freeing bpf_rb_root in
map_values.

structs bpf_rb_root and bpf_rb_node are opaque types meant to
obscure structs rb_root_cached rb_node, respectively.

btf_struct_access will prevent BPF programs from touching these special
fields automatically now that they're recognized.

btf_check_and_fixup_fields now groups list_head and rb_root together as
"graph root" fields and {list,rb}_node as "graph node", and does same
ownership cycle checking as before. Note that this function does _not_
prevent ownership type mixups (e.g. rb_root owning list_node) - that's
handled by btf_parse_graph_root.

After this patch, a bpf program can have a struct bpf_rb_root in a
map_value, but not add anything to nor do anything useful with it.

Signed-off-by: Dave Marchevsky 
Link: https://lore.kernel.org/r/20230214004017.2534011-2-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov 
Stable-dep-of: f6a6a5a97628 ("bpf: Fix struct_meta lookup for bpf_obj_free_fields kfunc call")
Signed-off-by: Sasha Levin

bpf: Migrate release_on_unlock logic to non-owning ref semantics

2023-05-11T14:11:11+00:00

[ Upstream commit 6a3cd3318ff65622415e34e8ee39d76331e7c869 ]

This patch introduces non-owning reference semantics to the verifier,
specifically linked_list API kfunc handling. release_on_unlock logic for
refs is refactored - with small functional changes - to implement these
semantics, and bpf_list_push_{front,back} are migrated to use them.

When a list node is pushed to a list, the program still has a pointer to
the node:

  n = bpf_obj_new(typeof(*n));

  bpf_spin_lock(&l);
  bpf_list_push_back(&l, n);
  /* n still points to the just-added node */
  bpf_spin_unlock(&l);

What the verifier considers n to be after the push, and thus what can be
done with n, are changed by this patch.

Common properties both before/after this patch:
  * After push, n is only a valid reference to the node until end of
    critical section
  * After push, n cannot be pushed to any list
  * After push, the program can read the node's fields using n

Before:
  * After push, n retains the ref_obj_id which it received on
    bpf_obj_new, but the associated bpf_reference_state's
    release_on_unlock field is set to true
    * release_on_unlock field and associated logic is used to implement
      "n is only a valid ref until end of critical section"
  * After push, n cannot be written to, the node must be removed from
    the list before writing to its fields
  * After push, n is marked PTR_UNTRUSTED

After:
  * After push, n's ref is released and ref_obj_id set to 0. NON_OWN_REF
    type flag is added to reg's type, indicating that it's a non-owning
    reference.
    * NON_OWN_REF flag and logic is used to implement "n is only a
      valid ref until end of critical section"
  * n can be written to (except for special fields e.g. bpf_list_node,
    timer, ...)

Summary of specific implementation changes to achieve the above:

  * release_on_unlock field, ref_set_release_on_unlock helper, and logic
    to "release on unlock" based on that field are removed

  * The anonymous active_lock struct used by bpf_verifier_state is
    pulled out into a named struct bpf_active_lock.

  * NON_OWN_REF type flag is introduced along with verifier logic
    changes to handle non-owning refs

  * Helpers are added to use NON_OWN_REF flag to implement non-owning
    ref semantics as described above
    * invalidate_non_owning_refs - helper to clobber all non-owning refs
      matching a particular bpf_active_lock identity. Replaces
      release_on_unlock logic in process_spin_lock.
    * ref_set_non_owning - set NON_OWN_REF type flag after doing some
      sanity checking
    * ref_convert_owning_non_owning - convert owning reference w/
      specified ref_obj_id to non-owning references. Set NON_OWN_REF
      flag for each reg with that ref_obj_id and 0-out its ref_obj_id

  * Update linked_list selftests to account for minor semantic
    differences introduced by this patch
    * Writes to a release_on_unlock node ref are not allowed, while
      writes to non-owning reference pointees are. As a result the
      linked_list "write after push" failure tests are no longer scenarios
      that should fail.
    * The test##missing_lock##op and test##incorrect_lock##op
      macro-generated failure tests need to have a valid node argument in
      order to have the same error output as before. Otherwise
      verification will fail early and the expected error output won't be seen.

Signed-off-by: Dave Marchevsky 
Link: https://lore.kernel.org/r/20230212092715.1422619-2-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov 
Stable-dep-of: f6a6a5a97628 ("bpf: Fix struct_meta lookup for bpf_obj_free_fields kfunc call")
Signed-off-by: Sasha Levin

bpf: Add __bpf_kfunc tag for marking kernel functions as kfuncs

2023-05-11T14:11:11+00:00

[ Upstream commit 57e7c169cd6afa093d858b8edfb9bceaf2e1c93b ]

kfuncs are functions defined in the kernel, which may be invoked by BPF
programs. They may or may not also be used as regular kernel functions,
implying that they may be static (in which case the compiler could e.g.
inline it away, or elide one or more arguments), or it could have
external linkage, but potentially be elided in an LTO build if a
function is observed to never be used, and is stripped from the final
kernel binary.

This has already resulted in some issues, such as those discussed in [0]
wherein changes in DWARF that identify when a parameter has been
optimized out can break BTF encodings (and in general break the kfunc).

[0]: https://lore.kernel.org/all/1675088985-20300-2-git-send-email-alan.maguire@oracle.com/

We therefore require some convenience macro that kfunc developers can
use just add to their kfuncs, and which will prevent all of the above
issues from happening. This is in contrast with what we have today,
where some kfunc definitions have "noinline", some have "__used", and
others are static and have neither.

Note that longer term, this mechanism may be replaced by a macro that
more closely resembles EXPORT_SYMBOL_GPL(), as described in [1]. For
now, we're going with this shorter-term approach to fix existing issues
in kfuncs.

[1]: https://lore.kernel.org/lkml/Y9AFT4pTydKh+PD3@maniforge.lan/

Note as well that checkpatch complains about this patch with the
following:

ERROR: Macros with complex values should be enclosed in parentheses
+#define __bpf_kfunc __used noinline

There seems to be a precedent for using this pattern in other places
such as compiler_types.h (see e.g. __randomize_layout and noinstr), so
it seems appropriate.

Signed-off-by: David Vernet 
Signed-off-by: Daniel Borkmann 
Acked-by: Stanislav Fomichev 
Link: https://lore.kernel.org/bpf/20230201173016.342758-2-void@manifault.com
Stable-dep-of: f6a6a5a97628 ("bpf: Fix struct_meta lookup for bpf_obj_free_fields kfunc call")
Signed-off-by: Sasha Levin

bpf: rename list_head -> graph_root in field info types

2023-05-11T14:11:11+00:00

[ Upstream commit 30465003ad776a922c32b2dac58db14f120f037e ]

Many of the structs recently added to track field info for linked-list
head are useful as-is for rbtree root. So let's do a mechanical renaming
of list_head-related types and fields:

include/linux/bpf.h:
  struct btf_field_list_head -> struct btf_field_graph_root
  list_head -> graph_root in struct btf_field union
kernel/bpf/btf.c:
  list_head -> graph_root in struct btf_field_info

This is a nonfunctional change, functionality to actually use these
fields for rbtree will be added in further patches.

Signed-off-by: Dave Marchevsky 
Link: https://lore.kernel.org/r/20221217082506.1570898-5-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov 
Stable-dep-of: f6a6a5a97628 ("bpf: Fix struct_meta lookup for bpf_obj_free_fields kfunc call")
Signed-off-by: Sasha Levin

bpf: return long from bpf_map_ops funcs

2023-05-11T14:11:09+00:00

[ Upstream commit d7ba4cc900bf1eea2d8c807c6b1fc6bd61f41237 ]

This patch changes the return types of bpf_map_ops functions to long, where
previously int was returned. Using long allows for bpf programs to maintain
the sign bit in the absence of sign extension during situations where
inlined bpf helper funcs make calls to the bpf_map_ops funcs and a negative
error is returned.

The definitions of the helper funcs are generated from comments in the bpf
uapi header at `include/uapi/linux/bpf.h`. The return type of these
helpers was previously changed from int to long in commit bdb7b79b4ce8. For
any case where one of the map helpers call the bpf_map_ops funcs that are
still returning 32-bit int, a compiler might not include sign extension
instructions to properly convert the 32-bit negative value a 64-bit
negative value.

For example:
bpf assembly excerpt of an inlined helper calling a kernel function and
checking for a specific error:

; err = bpf_map_update_elem(&mymap, &key, &val, BPF_NOEXIST);
  ...
  46:	call   0xffffffffe103291c	; htab_map_update_elem
; if (err && err != -EEXIST) {
  4b:	cmp    $0xffffffffffffffef,%rax ; cmp -EEXIST,%rax

kernel function assembly excerpt of return value from
`htab_map_update_elem` returning 32-bit int:

movl $0xffffffef, %r9d
...
movl %r9d, %eax

...results in the comparison:
cmp $0xffffffffffffffef, $0x00000000ffffffef

Fixes: bdb7b79b4ce8 ("bpf: Switch most helper return values from 32-bit int to 64-bit long")
Tested-by: Eduard Zingerman 
Signed-off-by: JP Kobryn 
Link: https://lore.kernel.org/r/20230322194754.185781-3-inwardvessel@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin