Merge branch 'Support storing struct task_struct objects as kptrs'

David Vernet says:

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

Now that BPF supports adding new kernel functions with kfuncs, and
storing kernel objects

Merge branch 'Support storing struct task_struct objects as kptrs'

David Vernet says:

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

Now that BPF supports adding new kernel functions with kfuncs, and
storing kernel objects in maps with kptrs, we can add a set of kfuncs
which allow struct task_struct objects to be stored in maps as
referenced kptrs.

The possible use cases for doing this are plentiful. During tracing,
for example, it would be useful to be able to collect some tasks that
performed a certain operation, and then periodically summarize who they
are, which cgroup they're in, how much CPU time they've utilized, etc.
Doing this now would require storing the tasks' pids along with some
relevant data to be exported to user space, and later associating the
pids to tasks in other event handlers where the data is recorded.
Another useful by-product of this is that it allows a program to pin a
task in a BPF program, and by proxy therefore also e.g. pin its task
local storage.

In order to support this, we'll need to expand KF_TRUSTED_ARGS to
support receiving trusted, non-refcounted pointers. It currently only
supports either PTR_TO_CTX pointers, or refcounted pointers. What this
means in terms of the implementation is that check_kfunc_args() would
have to also check for the PTR_TRUSTED or MEM_ALLOC type modifiers when
determining if a trusted KF_ARG_PTR_TO_ALLOC_BTF_ID or
KF_ARG_PTR_TO_BTF_ID pointer requires a refcount.

Note that PTR_UNTRUSTED is insufficient for this purpose, as it does not
cover all of the possible types of potentially unsafe pointers. For
example, a pointer obtained from walking a struct is not PTR_UNTRUSTED.
To account for this and enable us to expand KF_TRUSTED_ARGS to include
allow-listed arguments such as those passed by the kernel to tracepoints
and struct_ops callbacks, this patch set also introduces a new
PTR_TRUSTED type flag modifier which records if a pointer was obtained
passed from the kernel in a trusted context.

Currently, both PTR_TRUSTED and MEM_ALLOC are used to imply that a
pointer is trusted. Longer term, PTR_TRUSTED should be the sole source
of truth for whether a pointer is trusted. This requires us to set
PTR_TRUSTED when appropriate (e.g. when setting MEM_ALLOC), and unset it
when appropriate (e.g. when setting PTR_UNTRUSTED). We don't do that in
this patch, as we need to do more clean up before this can be done in a
clear and well-defined manner.

In closing, this patch set:

1. Adds the new PTR_TRUSTED register type modifier flag, and updates the
verifier and existing selftests accordingly. Also expands
KF_TRUSTED_ARGS to also include trusted pointers that were not obtained
from walking structs.
2. Adds a new set of kfuncs that allows struct task_struct* objects to be
used as kptrs.
3. Adds a new selftest suite to validate these new task kfuncs.
---
Changelog:
v8 -> v9:
- Moved check for release register back to where we check for
!PTR_TO_BTF_ID || socket. Change the verifier log message to
reflect really what's being tested (the presence of unsafe
modifiers) (Alexei)
- Fix verifier_test error tests to reflect above changes
- Remove unneeded parens around bitwise operator checks (Alexei)
- Move updates to reg_type_str() which allow multiple type modifiers
to be present in the prefix string, to a separate patch (Alexei)
- Increase TYPE_STR_BUF_LEN size to 128 to reflect larger prefix size
in reg_type_str().

v7 -> v8:
- Rebased onto Kumar's latest patch set which, adds a new MEM_ALLOC reg
type modifier for bpf_obj_new() calls.
- Added comments to bpf_task_kptr_get() describing some of the subtle
races we're protecting against (Alexei and John)
- Slightly rework process_kf_arg_ptr_to_btf_id(), and add a new
reg_has_unsafe_modifiers() function which validates that a register
containing a kfunc release arg doesn't have unsafe modifiers. Note
that this is slightly different than the check for KF_TRUSTED_ARGS.
An alternative here would be to treat KF_RELEASE as implicitly
requiring KF_TRUSTED_ARGS.
- Export inline bpf_type_has_unsafe_modifiers() function from
bpf_verifier.h so that it can be used from bpf_tcp_ca.c. Eventually this
function should likely be changed to bpf_type_is_trusted(), once
PTR_TRUSTED is the real source of truth.

v6 -> v7:
- Removed the PTR_WALKED type modifier, and instead define a new
PTR_TRUSTED type modifier which is set on registers containing
pointers passed from trusted contexts (i.e. as tracepoint or
struct_ops callback args) (Alexei)
- Remove the new KF_OWNED_ARGS kfunc flag. This can be accomplished
by defining a new type that wraps an existing type, such as with
struct nf_conn___init (Alexei)
- Add a test_task_current_acquire_release testcase which verifies we can
acquire a task struct returned from bpf_get_current_task_btf().
- Make bpf_task_acquire() no longer return NULL, as it can no longer be
called with a NULL task.
- Removed unnecessary is_test_kfunc_task() checks from failure
testcases.

v5 -> v6:
- Add a new KF_OWNED_ARGS kfunc flag which may be used by kfuncs to
express that they require trusted, refcounted args (Kumar)
- Rename PTR_NESTED -> PTR_WALKED in the verifier (Kumar)
- Convert reg_type_str() prefixes to use snprintf() instead of strncpy()
(Kumar)
- Add PTR_TO_BTF_ID | PTR_WALKED to missing struct btf_reg_type
instances -- specifically btf_id_sock_common_types, and
percpu_btf_ptr_types.
- Add a missing PTR_TO_BTF_ID | PTR_WALKED switch case entry in
check_func_arg_reg_off(), which is required when validating helper
calls (Kumar)
- Update reg_type_mismatch_ok() to check base types for the registers
(i.e. to accommodate type modifiers). Additionally, add a lengthy
comment that explains why this is being done (Kumar)
- Update convert_ctx_accesses() to also issue probe reads for
PTR_TO_BTF_ID | PTR_WALKED (Kumar)
- Update selftests to expect new prefix reg type strings.
- Rename task_kfunc_acquire_trusted_nested testcase to
task_kfunc_acquire_trusted_walked, and fix a comment (Kumar)
- Remove KF_TRUSTED_ARGS from bpf_task_release(), which already includes
KF_RELEASE (Kumar)
- Add bpf-next in patch subject lines (Kumar)

v4 -> v5:
- Fix an improperly formatted patch title.

v3 -> v4:
- Remove an unnecessary check from my repository that I forgot to remove
after debugging something.

v2 -> v3:
- Make bpf_task_acquire() check for NULL, and include KF_RET_NULL
(Martin)
- Include new PTR_NESTED register modifier type flag which specifies
whether a pointer was obtained from walking a struct. Use this to
expand the meaning of KF_TRUSTED_ARGS to include trusted pointers that
were passed from the kernel (Kumar)
- Add more selftests to the task_kfunc selftest suite which verify that
you cannot pass a walked pointer to bpf_task_acquire().
- Update bpf_task_acquire() to also specify KF_TRUSTED_ARGS.

v1 -> v2:
- Rename tracing_btf_ids to generic_kfunc_btf_ids, and add the new
kfuncs to that list instead of making a separate btf id list (Alexei).
- Don't run the new selftest suite on s390x, which doesn't appear to
support invoking kfuncs.
- Add a missing __diag_ignore block for -Wmissing-prototypes
(lkp@intel.com).
- Fix formatting on some of the SPDX-License-Identifier tags.
- Clarified the function header comment a bit on bpf_task_kptr_get().
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...

bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs

Kfuncs currently support specifying the KF_TRUSTED_ARGS flag to signal
to the verifier that it should enforce that a BPF program pa

bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs

Kfuncs currently support specifying the KF_TRUSTED_ARGS flag to signal
to the verifier that it should enforce that a BPF program passes it a
"safe", trusted pointer. Currently, "safe" means that the pointer is
either PTR_TO_CTX, or is refcounted. There may be cases, however, where
the kernel passes a BPF program a safe / trusted pointer to an object
that the BPF program wishes to use as a kptr, but because the object
does not yet have a ref_obj_id from the perspective of the verifier, the
program would be unable to pass it to a KF_ACQUIRE | KF_TRUSTED_ARGS
kfunc.

The solution is to expand the set of pointers that are considered
trusted according to KF_TRUSTED_ARGS, so that programs can invoke kfuncs
with these pointers without getting rejected by the verifier.

There is already a PTR_UNTRUSTED flag that is set in some scenarios,
such as when a BPF program reads a kptr directly from a map
without performing a bpf_kptr_xchg() call. These pointers of course can
and should be rejected by the verifier. Unfortunately, however,
PTR_UNTRUSTED does not cover all the cases for safety that need to
be addressed to adequately protect kfuncs. Specifically, pointers
obtained by a BPF program "walking" a struct are _not_ considered
PTR_UNTRUSTED according to BPF. For example, say that we were to add a
kfunc called bpf_task_acquire(), with KF_ACQUIRE | KF_TRUSTED_ARGS, to
acquire a struct task_struct *. If we only used PTR_UNTRUSTED to signal
that a task was unsafe to pass to a kfunc, the verifier would mistakenly
allow the following unsafe BPF program to be loaded:

SEC("tp_btf/task_newtask")
int BPF_PROG(unsafe_acquire_task,
struct task_struct *task,
u64 clone_flags)
{
struct task_struct *acquired, *nested;

nested = task->last_wakee;

/* Would not be rejected by the verifier. */
acquired = bpf_task_acquire(nested);
if (!acquired)
return 0;

bpf_task_release(acquired);
return 0;
}

To address this, this patch defines a new type flag called PTR_TRUSTED
which tracks whether a PTR_TO_BTF_ID pointer is safe to pass to a
KF_TRUSTED_ARGS kfunc or a BPF helper function. PTR_TRUSTED pointers are
passed directly from the kernel as a tracepoint or struct_ops callback
argument. Any nested pointer that is obtained from walking a PTR_TRUSTED
pointer is no longer PTR_TRUSTED. From the example above, the struct
task_struct *task argument is PTR_TRUSTED, but the 'nested' pointer
obtained from 'task->last_wakee' is not PTR_TRUSTED.

A subsequent patch will add kfuncs for storing a task kfunc as a kptr,
and then another patch will add selftests to validate.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221120051004.3605026-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...

Merge drm/drm-next into drm-intel-next

Catch up on 6.1-rc cycle in order to solve the intel_backlight
conflict on linux-next.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

ASoC: Set BQ parameters for some Dell models

There are some Dell SKUs that need to set the parameters of the
crossover filter (biquad). Each amplifier connects to one tweeter
speaker and one woofer

ASoC: Set BQ parameters for some Dell models

There are some Dell SKUs that need to set the parameters of the
crossover filter (biquad). Each amplifier connects to one tweeter
speaker and one woofer speaker. We should control HPF/LPF to output the
proper frequency for the different speakers. If the codec driver got
the BQ parameters from the device property, it will apply these
parameters to the hardware.

show more ...

Merge branch 'mana-shared-6.2' of https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Long Li says:

====================
Introduce Microsoft Azure Network Adapter (MANA) RDMA driver [netdev p

Merge branch 'mana-shared-6.2' of https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Long Li says:

====================
Introduce Microsoft Azure Network Adapter (MANA) RDMA driver [netdev prep]

The first 11 patches which modify the MANA Ethernet driver to support
RDMA driver.

* 'mana-shared-6.2' of https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
net: mana: Define data structures for protection domain and memory registration
net: mana: Define data structures for allocating doorbell page from GDMA
net: mana: Define and process GDMA response code GDMA_STATUS_MORE_ENTRIES
net: mana: Define max values for SGL entries
net: mana: Move header files to a common location
net: mana: Record port number in netdev
net: mana: Export Work Queue functions for use by RDMA driver
net: mana: Set the DMA device max segment size
net: mana: Handle vport sharing between devices
net: mana: Record the physical address for doorbell page region
net: mana: Add support for auxiliary device
====================

Link: https://lore.kernel.org/all/1667502990-2559-1-git-send-email-longli@linuxonhyperv.com/
Signed-off-by: Leon Romanovsky <leon@kernel.org>

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Merge drm/drm-next into drm-misc-next

Backmerging drm/drm-next to get the latest changes in the xlnx driver.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-next into drm-intel-gt-next

Needed to bring in v6.1-rc1 which contains commit f683b9d61319 ("i915: use the VMA iterator")
which is needed for series https://patchwork.freedesktop.org/s

Merge drm/drm-next into drm-intel-gt-next

Needed to bring in v6.1-rc1 which contains commit f683b9d61319 ("i915: use the VMA iterator")
which is needed for series https://patchwork.freedesktop.org/series/110083/ .

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
bpf-next 2022-11-02

We've added 70 non-merge commits during the la

Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
bpf-next 2022-11-02

We've added 70 non-merge commits during the last 14 day(s) which contain
a total of 96 files changed, 3203 insertions(+), 640 deletions(-).

The main changes are:

1) Make cgroup local storage available to non-cgroup attached BPF programs
such as tc BPF ones, from Yonghong Song.

2) Avoid unnecessary deadlock detection and failures wrt BPF task storage
helpers, from Martin KaFai Lau.

3) Add LLVM disassembler as default library for dumping JITed code
in bpftool, from Quentin Monnet.

4) Various kprobe_multi_link fixes related to kernel modules,
from Jiri Olsa.

5) Optimize x86-64 JIT with emitting BMI2-based shift instructions,
from Jie Meng.

6) Improve BPF verifier's memory type compatibility for map key/value
arguments, from Dave Marchevsky.

7) Only create mmap-able data section maps in libbpf when data is exposed
via skeletons, from Andrii Nakryiko.

8) Add an autoattach option for bpftool to load all object assets,
from Wang Yufen.

9) Various memory handling fixes for libbpf and BPF selftests,
from Xu Kuohai.

10) Initial support for BPF selftest's vmtest.sh on arm64,
from Manu Bretelle.

11) Improve libbpf's BTF handling to dedup identical structs,
from Alan Maguire.

12) Add BPF CI and denylist documentation for BPF selftests,
from Daniel Müller.

13) Check BPF cpumap max_entries before doing allocation work,
from Florian Lehner.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (70 commits)
samples/bpf: Fix typo in README
bpf: Remove the obsolte u64_stats_fetch_*_irq() users.
bpf: check max_entries before allocating memory
bpf: Fix a typo in comment for DFS algorithm
bpftool: Fix spelling mistake "disasembler" -> "disassembler"
selftests/bpf: Fix bpftool synctypes checking failure
selftests/bpf: Panic on hard/soft lockup
docs/bpf: Add documentation for new cgroup local storage
selftests/bpf: Add test cgrp_local_storage to DENYLIST.s390x
selftests/bpf: Add selftests for new cgroup local storage
selftests/bpf: Fix test test_libbpf_str/bpf_map_type_str
bpftool: Support new cgroup local storage
libbpf: Support new cgroup local storage
bpf: Implement cgroup storage available to non-cgroup-attached bpf progs
bpf: Refactor some inode/task/sk storage functions for reuse
bpf: Make struct cgroup btf id global
selftests/bpf: Tracing prog can still do lookup under busy lock
selftests/bpf: Ensure no task storage failure for bpf_lsm.s prog due to deadlock detection
bpf: Add new bpf_task_storage_delete proto with no deadlock detection
bpf: bpf_task_storage_delete_recur does lookup first before the deadlock check
...
====================

Link: https://lore.kernel.org/r/20221102062120.5724-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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Merge tag 'v6.1-rc2' into fixes

Merge rc2 into our fixes branch, which was based on rc1 but wasn't
merged until rc3, so that for the remainder of the release our fixes
branch will be based on rc2 fo

Merge tag 'v6.1-rc2' into fixes

Merge rc2 into our fixes branch, which was based on rc1 but wasn't
merged until rc3, so that for the remainder of the release our fixes
branch will be based on rc2 for the purposes of resolving conflicts with
other trees (if necessary).

show more ...

Merge 6.1-rc3 into usb-next

We need the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge branch 'bpf: Implement cgroup local storage available to non-cgroup-attached bpf progs'

Yonghong Song says:

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

There already exists a local storage implementation for cgrou

Merge branch 'bpf: Implement cgroup local storage available to non-cgroup-attached bpf progs'

Yonghong Song says:

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

There already exists a local storage implementation for cgroup-attached
bpf programs. See map type BPF_MAP_TYPE_CGROUP_STORAGE and helper
bpf_get_local_storage(). But there are use cases such that non-cgroup
attached bpf progs wants to access cgroup local storage data. For example,
tc egress prog has access to sk and cgroup. It is possible to use
sk local storage to emulate cgroup local storage by storing data in socket.
But this is a waste as it could be lots of sockets belonging to a particular
cgroup. Alternatively, a separate map can be created with cgroup id as the key.
But this will introduce additional overhead to manipulate the new map.
A cgroup local storage, similar to existing sk/inode/task storage,
should help for this use case.

This patch implemented new cgroup local storage available to
non-cgroup-attached bpf programs. In the patch series, Patches 1 and 2
are preparation patches. Patch 3 implemented new cgroup local storage
kernel support. Patches 4 and 5 implemented libbpf and bpftool support.
Patches 6-8 fixed one existing test and added four new tests to validate
kernel/libbpf implementations. Patch 9 added documentation for new
BPF_MAP_TYPE_CGRP_STORAGE map type and comparison of the old and new
cgroup local storage maps.

Changelogs:
v5 -> v6:
. fix selftest test_libbpf_str/bpf_map_type_str due to marking
BPF_MAP_TYPE_CGROUP_STORAGE as deprecated.
. add cgrp_local_storage test in s390x denylist since the test
has some fentry/fexit programs.
v4 -> v5:
. additional refactoring in patch 2
. fix the call site for bpf_cgrp_storage_free() in kernel/cgroup/cgroup.c.
. add a test for progs attaching to cgroups
. add a negative test (the helper key is a task instead of expected cgroup)
. some spelling fixes
v3 -> v4:
. fix a config guarding problem in kernel/cgroup/cgroup.c when
cgrp_storage is deleted (CONFIG_CGROUP_BPF => CONFIG_BPF_SYSCALL).
. rename selftest from cgroup_local_storage.c to cgrp_local_storage.c
so the name can better align with map name.
. fix a few misspellings.
v2 -> v3:
. fix a config caused kernel test complaint.
. better description/comments in uapi bpf.h and bpf_cgrp_storage.c.
. factor code for better resue for map_alloc/map_free.
. improved explanation in map documentation.
v1 -> v2:
. change map name from BPF_MAP_TYPE_CGROUP_LOCAL_STORAGE to
BPF_MAP_TYPE_CGRP_STORAGE.
. removed support of sleepable programs.
. changed the place of freeing cgrp local storage from put_css_set_locked()
to css_free_rwork_fn().
. added map documentation.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...

bpf: Implement cgroup storage available to non-cgroup-attached bpf progs

Similar to sk/inode/task storage, implement similar cgroup local storage.

There already exists a local storage implementatio

bpf: Implement cgroup storage available to non-cgroup-attached bpf progs

Similar to sk/inode/task storage, implement similar cgroup local storage.

There already exists a local storage implementation for cgroup-attached
bpf programs. See map type BPF_MAP_TYPE_CGROUP_STORAGE and helper
bpf_get_local_storage(). But there are use cases such that non-cgroup
attached bpf progs wants to access cgroup local storage data. For example,
tc egress prog has access to sk and cgroup. It is possible to use
sk local storage to emulate cgroup local storage by storing data in socket.
But this is a waste as it could be lots of sockets belonging to a particular
cgroup. Alternatively, a separate map can be created with cgroup id as the key.
But this will introduce additional overhead to manipulate the new map.
A cgroup local storage, similar to existing sk/inode/task storage,
should help for this use case.

The life-cycle of storage is managed with the life-cycle of the
cgroup struct. i.e. the storage is destroyed along with the owning cgroup
with a call to bpf_cgrp_storage_free() when cgroup itself
is deleted.

The userspace map operations can be done by using a cgroup fd as a key
passed to the lookup, update and delete operations.

Typically, the following code is used to get the current cgroup:
struct task_struct *task = bpf_get_current_task_btf();
... task->cgroups->dfl_cgrp ...
and in structure task_struct definition:
struct task_struct {
....
struct css_set __rcu *cgroups;
....
}
With sleepable program, accessing task->cgroups is not protected by rcu_read_lock.
So the current implementation only supports non-sleepable program and supporting
sleepable program will be the next step together with adding rcu_read_lock
protection for rcu tagged structures.

Since map name BPF_MAP_TYPE_CGROUP_STORAGE has been used for old cgroup local
storage support, the new map name BPF_MAP_TYPE_CGRP_STORAGE is used
for cgroup storage available to non-cgroup-attached bpf programs. The old
cgroup storage supports bpf_get_local_storage() helper to get the cgroup data.
The new cgroup storage helper bpf_cgrp_storage_get() can provide similar
functionality. While old cgroup storage pre-allocates storage memory, the new
mechanism can also pre-allocate with a user space bpf_map_update_elem() call
to avoid potential run-time memory allocation failure.
Therefore, the new cgroup storage can provide all functionality w.r.t.
the old one. So in uapi bpf.h, the old BPF_MAP_TYPE_CGROUP_STORAGE is alias to
BPF_MAP_TYPE_CGROUP_STORAGE_DEPRECATED to indicate the old cgroup storage can
be deprecated since the new one can provide the same functionality.

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221026042850.673791-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...

Merge branch 'bpf: Avoid unnecessary deadlock detection and failure in task storage'

Martin KaFai Lau says:

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

From: Martin KaFai Lau <martin.lau@kernel.org>

The commit bc235cdb

Merge branch 'bpf: Avoid unnecessary deadlock detection and failure in task storage'

Martin KaFai Lau says:

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

From: Martin KaFai Lau <martin.lau@kernel.org>

The commit bc235cdb423a ("bpf: Prevent deadlock from recursive bpf_task_storage_[get|delete]")
added deadlock detection to avoid a tracing program from recurring
on the bpf_task_storage_{get,delete}() helpers. These helpers acquire
a spin lock and it will lead to deadlock.

It is unnecessary for the bpf_lsm and bpf_iter programs which do
not recur. The situation is the same as the existing
bpf_pid_task_storage_{lookup,delete}_elem() which are
used in the syscall and they also do not have deadlock detection.

This set is to add new bpf_task_storage_{get,delete}() helper proto
without the deadlock detection. The set also removes the prog->active
check from the bpf_lsm and bpf_iter program. Please see the individual
patch for details.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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bpf: Add new bpf_task_storage_delete proto with no deadlock detection

The bpf_lsm and bpf_iter do not recur that will cause a deadlock.
The situation is similar to the bpf_pid_task_storage_delete_el

bpf: Add new bpf_task_storage_delete proto with no deadlock detection

The bpf_lsm and bpf_iter do not recur that will cause a deadlock.
The situation is similar to the bpf_pid_task_storage_delete_elem()
which is called from the syscall map_delete_elem. It does not need
deadlock detection. Otherwise, it will cause unnecessary failure
when calling the bpf_task_storage_delete() helper.

This patch adds bpf_task_storage_delete proto that does not do deadlock
detection. It will be used by bpf_lsm and bpf_iter program.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20221025184524.3526117-8-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...

bpf: Add new bpf_task_storage_get proto with no deadlock detection

The bpf_lsm and bpf_iter do not recur that will cause a deadlock.
The situation is similar to the bpf_pid_task_storage_lookup_elem(

bpf: Add new bpf_task_storage_get proto with no deadlock detection

The bpf_lsm and bpf_iter do not recur that will cause a deadlock.
The situation is similar to the bpf_pid_task_storage_lookup_elem()
which is called from the syscall map_lookup_elem. It does not need
deadlock detection. Otherwise, it will cause unnecessary failure
when calling the bpf_task_storage_get() helper.

This patch adds bpf_task_storage_get proto that does not do deadlock
detection. It will be used by bpf_lsm and bpf_iter programs.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20221025184524.3526117-6-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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bpf: Append _recur naming to the bpf_task_storage helper proto

This patch adds the "_recur" naming to the bpf_task_storage_{get,delete}
proto. In a latter patch, they will only be used by the traci

bpf: Append _recur naming to the bpf_task_storage helper proto

This patch adds the "_recur" naming to the bpf_task_storage_{get,delete}
proto. In a latter patch, they will only be used by the tracing
programs that requires a deadlock detection because a tracing
prog may use bpf_task_storage_{get,delete} recursively and cause a
deadlock.

Another following patch will add a different helper proto for the non
tracing programs because they do not need the deadlock prevention.
This patch does this rename to prepare for this future proto
additions.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20221025184524.3526117-3-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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Merge branch 'bpf: Fixes for kprobe multi on kernel modules'

Jiri Olsa says:

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

hi,
Martynas reported kprobe _multi link does not resolve symbols
from kernel modules, which attac

Merge branch 'bpf: Fixes for kprobe multi on kernel modules'

Jiri Olsa says:

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

hi,
Martynas reported kprobe _multi link does not resolve symbols
from kernel modules, which attach by address works.

In addition while fixing that I realized we do not take module
reference if the module has kprobe_multi link on top of it and
can be removed.

There's mo crash related to this, it will silently disappear from
ftrace tables, while kprobe_multi link stays up with no data.

This patchset has fixes for both issues.

v3 changes:
- reorder fields in struct bpf_kprobe_multi_link [Andrii]
- added ack [Andrii]

v2 changes:
- added acks (Song)
- added comment to kallsyms_callback (Song)
- change module_callback realloc logic (Andrii)
- get rid of macros in tests (Andrii)

thanks,
jirka
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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bpf: Take module reference on kprobe_multi link

Currently we allow to create kprobe multi link on function from kernel
module, but we don't take the module reference to ensure it's not
unloaded whil

bpf: Take module reference on kprobe_multi link

Currently we allow to create kprobe multi link on function from kernel
module, but we don't take the module reference to ensure it's not
unloaded while we are tracing it.

The multi kprobe link is based on fprobe/ftrace layer which takes
different approach and releases ftrace hooks when module is unloaded
even if there's tracer registered on top of it.

Adding code that gathers all the related modules for the link and takes
their references before it's attached. All kernel module references are
released after link is unregistered.

Note that we do it the same way already for trampoline probes
(but for single address).

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20221025134148.3300700-5-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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bpf: Rename __bpf_kprobe_multi_cookie_cmp to bpf_kprobe_multi_addrs_cmp

Renaming __bpf_kprobe_multi_cookie_cmp to bpf_kprobe_multi_addrs_cmp,
because it's more suitable to current and upcoming code.

bpf: Rename __bpf_kprobe_multi_cookie_cmp to bpf_kprobe_multi_addrs_cmp

Renaming __bpf_kprobe_multi_cookie_cmp to bpf_kprobe_multi_addrs_cmp,
because it's more suitable to current and upcoming code.

Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20221025134148.3300700-4-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

include/linux/net.h
a5ef058dc4d9 ("net: introduce and use custom sockopt socket flag")
e993ffe3da4b ("net: flag sockets supporting

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

include/linux/net.h
a5ef058dc4d9 ("net: introduce and use custom sockopt socket flag")
e993ffe3da4b ("net: flag sockets supporting msghdr originated zerocopy")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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Merge branch 'main' into zstd-next

Merge remote-tracking branch 'drm/drm-fixes' into drm-misc-fixes

Update to v6.1-rc2 to grab more fixes.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

Merge tag 'perf_urgent_for_v6.1_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Borislav Petkov:

- Fix raw data handling when perf events are used in bpf

- Rew

Merge tag 'perf_urgent_for_v6.1_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Borislav Petkov:

- Fix raw data handling when perf events are used in bpf

- Rework how SIGTRAPs get delivered to events to address a bunch of
problems with it. Add a selftest for that too

* tag 'perf_urgent_for_v6.1_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
bpf: Fix sample_flags for bpf_perf_event_output
selftests/perf_events: Add a SIGTRAP stress test with disables
perf: Fix missing SIGTRAPs

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Merge branch 'main' into zstd-next

Merge drm/drm-fixes into drm-misc-fixes

Backmerging to get v6.1-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>