43112 Commits

Author SHA1 Message Date
Oleg Nesterov
3466abafa9 zap_pid_ns_processes: clear TIF_NOTIFY_SIGNAL along with TIF_SIGPENDING
[ Upstream commit 7fea700e04bd3f424c2d836e98425782f97b494e ]

kernel_wait4() doesn't sleep and returns -EINTR if there is no
eligible child and signal_pending() is true.

That is why zap_pid_ns_processes() clears TIF_SIGPENDING but this is not
enough, it should also clear TIF_NOTIFY_SIGNAL to make signal_pending()
return false and avoid a busy-wait loop.

Link: https://lkml.kernel.org/r/20240608120616.GB7947@redhat.com
Fixes: 12db8b690010 ("entry: Add support for TIF_NOTIFY_SIGNAL")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Rachel Menge <rachelmenge@linux.microsoft.com>
Closes: https://lore.kernel.org/all/1386cd49-36d0-4a5c-85e9-bc42056a5a38@linux.microsoft.com/
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Tested-by: Wei Fu <fuweid89@gmail.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Allen Pais <apais@linux.microsoft.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Joel Granados <j.granados@samsung.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Zqiang <qiang.zhang1211@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:50 +02:00
Sam James
dd782da470 Revert "fork: defer linking file vma until vma is fully initialized"
This reverts commit cec11fa2eb512ebe3a459c185f4aca1d44059bbf which is commit
35e351780fa9d8240dd6f7e4f245f9ea37e96c19 upstream.

The backport is incomplete and causes xfstests failures. The consequences
of the incomplete backport seem worse than the original issue, so pick
the lesser evil and revert until a full backport is ready.

Link: https://lore.kernel.org/stable/20240604004751.3883227-1-leah.rumancik@gmail.com/
Reported-by: Leah Rumancik <leah.rumancik@gmail.com>
Signed-off-by: Sam James <sam@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:47 +02:00
Oleg Nesterov
93d61e1bac tick/nohz_full: Don't abuse smp_call_function_single() in tick_setup_device()
commit 07c54cc5988f19c9642fd463c2dbdac7fc52f777 upstream.

After the recent commit 5097cbcb38e6 ("sched/isolation: Prevent boot crash
when the boot CPU is nohz_full") the kernel no longer crashes, but there is
another problem.

In this case tick_setup_device() calls tick_take_do_timer_from_boot() to
update tick_do_timer_cpu and this triggers the WARN_ON_ONCE(irqs_disabled)
in smp_call_function_single().

Kill tick_take_do_timer_from_boot() and just use WRITE_ONCE(), the new
comment explains why this is safe (thanks Thomas!).

Fixes: 08ae95f4fd3b ("nohz_full: Allow the boot CPU to be nohz_full")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240528122019.GA28794@redhat.com
Link: https://lore.kernel.org/all/20240522151742.GA10400@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:46 +02:00
Petr Tesarik
f8474caf39 swiotlb: extend buffer pre-padding to alloc_align_mask if necessary
commit af133562d5aff41fcdbe51f1a504ae04788b5fc0 upstream.

Allow a buffer pre-padding of up to alloc_align_mask, even if it requires
allocating additional IO TLB slots.

If the allocation alignment is bigger than IO_TLB_SIZE and min_align_mask
covers any non-zero bits in the original address between IO_TLB_SIZE and
alloc_align_mask, these bits are not preserved in the swiotlb buffer
address.

To fix this case, increase the allocation size and use a larger offset
within the allocated buffer. As a result, extra padding slots may be
allocated before the mapping start address.

Leave orig_addr in these padding slots initialized to INVALID_PHYS_ADDR.
These slots do not correspond to any CPU buffer, so attempts to sync the
data should be ignored.

The padding slots should be automatically released when the buffer is
unmapped. However, swiotlb_tbl_unmap_single() takes only the address of the
DMA buffer slot, not the first padding slot. Save the number of padding
slots in struct io_tlb_slot and use it to adjust the slot index in
swiotlb_release_slots(), so all allocated slots are properly freed.

Cc: stable@vger.kernel.org # v6.6+
Fixes: 2fd4fa5d3fb5 ("swiotlb: Fix alignment checks when both allocation and DMA masks are present")
Link: https://lore.kernel.org/linux-iommu/20240311210507.217daf8b@meshulam.tesarici.cz/
Signed-off-by: Petr Tesarik <petr.tesarik1@huawei-partners.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:46 +02:00
Will Deacon
6c385c1fa0 swiotlb: Reinstate page-alignment for mappings >= PAGE_SIZE
commit 14cebf689a78e8a1c041138af221ef6eac6bc7da upstream.

For swiotlb allocations >= PAGE_SIZE, the slab search historically
adjusted the stride to avoid checking unaligned slots. This had the
side-effect of aligning large mapping requests to PAGE_SIZE, but that
was broken by 0eee5ae10256 ("swiotlb: fix slot alignment checks").

Since this alignment could be relied upon drivers, reinstate PAGE_SIZE
alignment for swiotlb mappings >= PAGE_SIZE.

Cc: stable@vger.kernel.org # v6.6+
Reported-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Will Deacon <will@kernel.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Petr Tesarik <petr.tesarik1@huawei-partners.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:46 +02:00
Will Deacon
6033fc9522 swiotlb: Enforce page alignment in swiotlb_alloc()
commit 823353b7cf0ea9dfb09f5181d5fb2825d727200b upstream.

When allocating pages from a restricted DMA pool in swiotlb_alloc(),
the buffer address is blindly converted to a 'struct page *' that is
returned to the caller. In the unlikely event of an allocation bug,
page-unaligned addresses are not detected and slots can silently be
double-allocated.

Add a simple check of the buffer alignment in swiotlb_alloc() to make
debugging a little easier if something has gone wonky.

Cc: stable@vger.kernel.org # v6.6+
Signed-off-by: Will Deacon <will@kernel.org>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Petr Tesarik <petr.tesarik1@huawei-partners.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:46 +02:00
Matthias Maennich
5fc6b708ef kheaders: explicitly define file modes for archived headers
commit 3bd27a847a3a4827a948387cc8f0dbc9fa5931d5 upstream.

Build environments might be running with different umask settings
resulting in indeterministic file modes for the files contained in
kheaders.tar.xz. The file itself is served with 444, i.e. world
readable. Archive the files explicitly with 744,a+X to improve
reproducibility across build environments.

--mode=0444 is not suitable as directories need to be executable. Also,
444 makes it hard to delete all the readonly files after extraction.

Cc: stable@vger.kernel.org
Signed-off-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:40 +02:00
Haifeng Xu
809a2ed171 perf/core: Fix missing wakeup when waiting for context reference
commit 74751ef5c1912ebd3e65c3b65f45587e05ce5d36 upstream.

In our production environment, we found many hung tasks which are
blocked for more than 18 hours. Their call traces are like this:

[346278.191038] __schedule+0x2d8/0x890
[346278.191046] schedule+0x4e/0xb0
[346278.191049] perf_event_free_task+0x220/0x270
[346278.191056] ? init_wait_var_entry+0x50/0x50
[346278.191060] copy_process+0x663/0x18d0
[346278.191068] kernel_clone+0x9d/0x3d0
[346278.191072] __do_sys_clone+0x5d/0x80
[346278.191076] __x64_sys_clone+0x25/0x30
[346278.191079] do_syscall_64+0x5c/0xc0
[346278.191083] ? syscall_exit_to_user_mode+0x27/0x50
[346278.191086] ? do_syscall_64+0x69/0xc0
[346278.191088] ? irqentry_exit_to_user_mode+0x9/0x20
[346278.191092] ? irqentry_exit+0x19/0x30
[346278.191095] ? exc_page_fault+0x89/0x160
[346278.191097] ? asm_exc_page_fault+0x8/0x30
[346278.191102] entry_SYSCALL_64_after_hwframe+0x44/0xae

The task was waiting for the refcount become to 1, but from the vmcore,
we found the refcount has already been 1. It seems that the task didn't
get woken up by perf_event_release_kernel() and got stuck forever. The
below scenario may cause the problem.

Thread A					Thread B
...						...
perf_event_free_task				perf_event_release_kernel
						   ...
						   acquire event->child_mutex
						   ...
						   get_ctx
   ...						   release event->child_mutex
   acquire ctx->mutex
   ...
   perf_free_event (acquire/release event->child_mutex)
   ...
   release ctx->mutex
   wait_var_event
						   acquire ctx->mutex
						   acquire event->child_mutex
						   # move existing events to free_list
						   release event->child_mutex
						   release ctx->mutex
						   put_ctx
...						...

In this case, all events of the ctx have been freed, so we couldn't
find the ctx in free_list and Thread A will miss the wakeup. It's thus
necessary to add a wakeup after dropping the reference.

Fixes: 1cf8dfe8a661 ("perf/core: Fix race between close() and fork()")
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20240513103948.33570-1-haifeng.xu@shopee.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:39 +02:00
Andrii Nakryiko
39a143a2b0 bpf: fix multi-uprobe PID filtering logic
[ Upstream commit 46ba0e49b64232adac35a2bc892f1710c5b0fb7f ]

Current implementation of PID filtering logic for multi-uprobes in
uprobe_prog_run() is filtering down to exact *thread*, while the intent
for PID filtering it to filter by *process* instead. The check in
uprobe_prog_run() also differs from the analogous one in
uprobe_multi_link_filter() for some reason. The latter is correct,
checking task->mm, not the task itself.

Fix the check in uprobe_prog_run() to perform the same task->mm check.

While doing this, we also update get_pid_task() use to use PIDTYPE_TGID
type of lookup, given the intent is to get a representative task of an
entire process. This doesn't change behavior, but seems more logical. It
would hold task group leader task now, not any random thread task.

Last but not least, given multi-uprobe support is half-broken due to
this PID filtering logic (depending on whether PID filtering is
important or not), we need to make it easy for user space consumers
(including libbpf) to easily detect whether PID filtering logic was
already fixed.

We do it here by adding an early check on passed pid parameter. If it's
negative (and so has no chance of being a valid PID), we return -EINVAL.
Previous behavior would eventually return -ESRCH ("No process found"),
given there can't be any process with negative PID. This subtle change
won't make any practical change in behavior, but will allow applications
to detect PID filtering fixes easily. Libbpf fixes take advantage of
this in the next patch.

Cc: stable@vger.kernel.org
Acked-by: Jiri Olsa <jolsa@kernel.org>
Fixes: b733eeade420 ("bpf: Add pid filter support for uprobe_multi link")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240521163401.3005045-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:22 +02:00
Cong Wang
91cff53136 bpf: Fix a potential use-after-free in bpf_link_free()
[ Upstream commit 2884dc7d08d98a89d8d65121524bb7533183a63a ]

After commit 1a80dbcb2dba, bpf_link can be freed by
link->ops->dealloc_deferred, but the code still tests and uses
link->ops->dealloc afterward, which leads to a use-after-free as
reported by syzbot. Actually, one of them should be sufficient, so
just call one of them instead of both. Also add a WARN_ON() in case
of any problematic implementation.

Fixes: 1a80dbcb2dba ("bpf: support deferring bpf_link dealloc to after RCU grace period")
Reported-by: syzbot+1989ee16d94720836244@syzkaller.appspotmail.com
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20240602182703.207276-1-xiyou.wangcong@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:15 +02:00
Hou Tao
2ad2f2edb9 bpf: Optimize the free of inner map
[ Upstream commit af66bfd3c8538ed21cf72af18426fc4a408665cf ]

When removing the inner map from the outer map, the inner map will be
freed after one RCU grace period and one RCU tasks trace grace
period, so it is certain that the bpf program, which may access the
inner map, has exited before the inner map is freed.

However there is no need to wait for one RCU tasks trace grace period if
the outer map is only accessed by non-sleepable program. So adding
sleepable_refcnt in bpf_map and increasing sleepable_refcnt when adding
the outer map into env->used_maps for sleepable program. Although the
max number of bpf program is INT_MAX - 1, the number of bpf programs
which are being loaded may be greater than INT_MAX, so using atomic64_t
instead of atomic_t for sleepable_refcnt. When removing the inner map
from the outer map, using sleepable_refcnt to decide whether or not a
RCU tasks trace grace period is needed before freeing the inner map.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20231204140425.1480317-6-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Stable-dep-of: 2884dc7d08d9 ("bpf: Fix a potential use-after-free in bpf_link_free()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:15 +02:00
Jiri Olsa
5aa03dd388 bpf: Store ref_ctr_offsets values in bpf_uprobe array
[ Upstream commit 4930b7f53a298533bc31d7540b6ea8b79a000331 ]

We will need to return ref_ctr_offsets values through link_info
interface in following change, so we need to keep them around.

Storing ref_ctr_offsets values directly into bpf_uprobe array.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20231125193130.834322-3-jolsa@kernel.org
Stable-dep-of: 2884dc7d08d9 ("bpf: Fix a potential use-after-free in bpf_link_free()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:14 +02:00
dicken.ding
1c7891812d genirq/irqdesc: Prevent use-after-free in irq_find_at_or_after()
commit b84a8aba806261d2f759ccedf4a2a6a80a5e55ba upstream.

irq_find_at_or_after() dereferences the interrupt descriptor which is
returned by mt_find() while neither holding sparse_irq_lock nor RCU read
lock, which means the descriptor can be freed between mt_find() and the
dereference:

    CPU0                            CPU1
    desc = mt_find()
                                    delayed_free_desc(desc)
    irq_desc_get_irq(desc)

The use-after-free is reported by KASAN:

    Call trace:
     irq_get_next_irq+0x58/0x84
     show_stat+0x638/0x824
     seq_read_iter+0x158/0x4ec
     proc_reg_read_iter+0x94/0x12c
     vfs_read+0x1e0/0x2c8

    Freed by task 4471:
     slab_free_freelist_hook+0x174/0x1e0
     __kmem_cache_free+0xa4/0x1dc
     kfree+0x64/0x128
     irq_kobj_release+0x28/0x3c
     kobject_put+0xcc/0x1e0
     delayed_free_desc+0x14/0x2c
     rcu_do_batch+0x214/0x720

Guard the access with a RCU read lock section.

Fixes: 721255b9826b ("genirq: Use a maple tree for interrupt descriptor management")
Signed-off-by: dicken.ding <dicken.ding@mediatek.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240524091739.31611-1-dicken.ding@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:46 +02:00
Daniel Thompson
ea303a7af8 kdb: Use format-specifiers rather than memset() for padding in kdb_read()
commit c9b51ddb66b1d96e4d364c088da0f1dfb004c574 upstream.

Currently when the current line should be removed from the display
kdb_read() uses memset() to fill a temporary buffer with spaces.
The problem is not that this could be trivially implemented using a
format string rather than open coding it. The real problem is that
it is possible, on systems with a long kdb_prompt_str, to write past
the end of the tmpbuffer.

Happily, as mentioned above, this can be trivially implemented using a
format string. Make it so!

Cc: stable@vger.kernel.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20240424-kgdb_read_refactor-v3-5-f236dbe9828d@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:44 +02:00
Daniel Thompson
e00ec562b0 kdb: Merge identical case statements in kdb_read()
commit 6244917f377bf64719551b58592a02a0336a7439 upstream.

The code that handles case 14 (down) and case 16 (up) has been copy and
pasted despite being byte-for-byte identical. Combine them.

Cc: stable@vger.kernel.org # Not a bug fix but it is needed for later bug fixes
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20240424-kgdb_read_refactor-v3-4-f236dbe9828d@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:44 +02:00
Daniel Thompson
958ba65a35 kdb: Fix console handling when editing and tab-completing commands
commit db2f9c7dc29114f531df4a425d0867d01e1f1e28 upstream.

Currently, if the cursor position is not at the end of the command buffer
and the user uses the Tab-complete functions, then the console does not
leave the cursor in the correct position.

For example consider the following buffer with the cursor positioned
at the ^:

md kdb_pro 10
          ^

Pressing tab should result in:

md kdb_prompt_str 10
                 ^

However this does not happen. Instead the cursor is placed at the end
(after then 10) and further cursor movement redraws incorrectly. The
same problem exists when we double-Tab but in a different part of the
code.

Fix this by sending a carriage return and then redisplaying the text to
the left of the cursor.

Cc: stable@vger.kernel.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20240424-kgdb_read_refactor-v3-3-f236dbe9828d@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:43 +02:00
Daniel Thompson
d373d3c633 kdb: Use format-strings rather than '\0' injection in kdb_read()
commit 09b35989421dfd5573f0b4683c7700a7483c71f9 upstream.

Currently when kdb_read() needs to reposition the cursor it uses copy and
paste code that works by injecting an '\0' at the cursor position before
delivering a carriage-return and reprinting the line (which stops at the
'\0').

Tidy up the code by hoisting the copy and paste code into an appropriately
named function. Additionally let's replace the '\0' injection with a
proper field width parameter so that the string will be abridged during
formatting instead.

Cc: stable@vger.kernel.org # Not a bug fix but it is needed for later bug fixes
Tested-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240424-kgdb_read_refactor-v3-2-f236dbe9828d@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:43 +02:00
Daniel Thompson
107e825cc4 kdb: Fix buffer overflow during tab-complete
commit e9730744bf3af04cda23799029342aa3cddbc454 upstream.

Currently, when the user attempts symbol completion with the Tab key, kdb
will use strncpy() to insert the completed symbol into the command buffer.
Unfortunately it passes the size of the source buffer rather than the
destination to strncpy() with predictably horrible results. Most obviously
if the command buffer is already full but cp, the cursor position, is in
the middle of the buffer, then we will write past the end of the supplied
buffer.

Fix this by replacing the dubious strncpy() calls with memmove()/memcpy()
calls plus explicit boundary checks to make sure we have enough space
before we start moving characters around.

Reported-by: Justin Stitt <justinstitt@google.com>
Closes: https://lore.kernel.org/all/CAFhGd8qESuuifuHsNjFPR-Va3P80bxrw+LqvC8deA8GziUJLpw@mail.gmail.com/
Cc: stable@vger.kernel.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Tested-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20240424-kgdb_read_refactor-v3-1-f236dbe9828d@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:43 +02:00
Dongli Zhang
59f86a2908 genirq/cpuhotplug, x86/vector: Prevent vector leak during CPU offline
commit a6c11c0a5235fb144a65e0cb2ffd360ddc1f6c32 upstream.

The absence of IRQD_MOVE_PCNTXT prevents immediate effectiveness of
interrupt affinity reconfiguration via procfs. Instead, the change is
deferred until the next instance of the interrupt being triggered on the
original CPU.

When the interrupt next triggers on the original CPU, the new affinity is
enforced within __irq_move_irq(). A vector is allocated from the new CPU,
but the old vector on the original CPU remains and is not immediately
reclaimed. Instead, apicd->move_in_progress is flagged, and the reclaiming
process is delayed until the next trigger of the interrupt on the new CPU.

Upon the subsequent triggering of the interrupt on the new CPU,
irq_complete_move() adds a task to the old CPU's vector_cleanup list if it
remains online. Subsequently, the timer on the old CPU iterates over its
vector_cleanup list, reclaiming old vectors.

However, a rare scenario arises if the old CPU is outgoing before the
interrupt triggers again on the new CPU.

In that case irq_force_complete_move() is not invoked on the outgoing CPU
to reclaim the old apicd->prev_vector because the interrupt isn't currently
affine to the outgoing CPU, and irq_needs_fixup() returns false. Even
though __vector_schedule_cleanup() is later called on the new CPU, it
doesn't reclaim apicd->prev_vector; instead, it simply resets both
apicd->move_in_progress and apicd->prev_vector to 0.

As a result, the vector remains unreclaimed in vector_matrix, leading to a
CPU vector leak.

To address this issue, move the invocation of irq_force_complete_move()
before the irq_needs_fixup() call to reclaim apicd->prev_vector, if the
interrupt is currently or used to be affine to the outgoing CPU.

Additionally, reclaim the vector in __vector_schedule_cleanup() as well,
following a warning message, although theoretically it should never see
apicd->move_in_progress with apicd->prev_cpu pointing to an offline CPU.

Fixes: f0383c24b485 ("genirq/cpuhotplug: Add support for cleaning up move in progress")
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240522220218.162423-1-dongli.zhang@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-12 11:13:01 +02:00
Miguel Ojeda
db93128536 kheaders: use command -v to test for existence of cpio
[ Upstream commit 6e58e0173507e506a5627741358bc770f220e356 ]

Commit 13e1df09284d ("kheaders: explicitly validate existence of cpio
command") added an explicit check for `cpio` using `type`.

However, `type` in `dash` (which is used in some popular distributions
and base images as the shell script runner) prints the missing message
to standard output, and thus no error is printed:

    $ bash -c 'type missing >/dev/null'
    bash: line 1: type: missing: not found
    $ dash -c 'type missing >/dev/null'
    $

For instance, this issue may be seen by loongarch builders, given its
defconfig enables CONFIG_IKHEADERS since commit 9cc1df421f00 ("LoongArch:
Update Loongson-3 default config file").

Therefore, use `command -v` instead to have consistent behavior, and
take the chance to provide a more explicit error.

Fixes: 13e1df09284d ("kheaders: explicitly validate existence of cpio command")
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:58 +02:00
Jakub Sitnicki
000a65bf1d bpf: Allow delete from sockmap/sockhash only if update is allowed
[ Upstream commit 98e948fb60d41447fd8d2d0c3b8637fc6b6dc26d ]

We have seen an influx of syzkaller reports where a BPF program attached to
a tracepoint triggers a locking rule violation by performing a map_delete
on a sockmap/sockhash.

We don't intend to support this artificial use scenario. Extend the
existing verifier allowed-program-type check for updating sockmap/sockhash
to also cover deleting from a map.

From now on only BPF programs which were previously allowed to update
sockmap/sockhash can delete from these map types.

Fixes: ff9105993240 ("bpf, sockmap: Prevent lock inversion deadlock in map delete elem")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: syzbot+ec941d6e24f633a59172@syzkaller.appspotmail.com
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: syzbot+ec941d6e24f633a59172@syzkaller.appspotmail.com
Acked-by: John Fastabend <john.fastabend@gmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=ec941d6e24f633a59172
Link: https://lore.kernel.org/bpf/20240527-sockmap-verify-deletes-v1-1-944b372f2101@cloudflare.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:56 +02:00
Fedor Pchelkin
5a91116b00 dma-mapping: benchmark: handle NUMA_NO_NODE correctly
[ Upstream commit e64746e74f717961250a155e14c156616fcd981f ]

cpumask_of_node() can be called for NUMA_NO_NODE inside do_map_benchmark()
resulting in the following sanitizer report:

UBSAN: array-index-out-of-bounds in ./arch/x86/include/asm/topology.h:72:28
index -1 is out of range for type 'cpumask [64][1]'
CPU: 1 PID: 990 Comm: dma_map_benchma Not tainted 6.9.0-rc6 #29
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
 <TASK>
dump_stack_lvl (lib/dump_stack.c:117)
ubsan_epilogue (lib/ubsan.c:232)
__ubsan_handle_out_of_bounds (lib/ubsan.c:429)
cpumask_of_node (arch/x86/include/asm/topology.h:72) [inline]
do_map_benchmark (kernel/dma/map_benchmark.c:104)
map_benchmark_ioctl (kernel/dma/map_benchmark.c:246)
full_proxy_unlocked_ioctl (fs/debugfs/file.c:333)
__x64_sys_ioctl (fs/ioctl.c:890)
do_syscall_64 (arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Use cpumask_of_node() in place when binding a kernel thread to a cpuset
of a particular node.

Note that the provided node id is checked inside map_benchmark_ioctl().
It's just a NUMA_NO_NODE case which is not handled properly later.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 65789daa8087 ("dma-mapping: add benchmark support for streaming DMA APIs")
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Acked-by: Barry Song <baohua@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:52 +02:00
Fedor Pchelkin
34a816d873 dma-mapping: benchmark: fix node id validation
[ Upstream commit 1ff05e723f7ca30644b8ec3fb093f16312e408ad ]

While validating node ids in map_benchmark_ioctl(), node_possible() may
be provided with invalid argument outside of [0,MAX_NUMNODES-1] range
leading to:

BUG: KASAN: wild-memory-access in map_benchmark_ioctl (kernel/dma/map_benchmark.c:214)
Read of size 8 at addr 1fffffff8ccb6398 by task dma_map_benchma/971
CPU: 7 PID: 971 Comm: dma_map_benchma Not tainted 6.9.0-rc6 #37
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
 <TASK>
dump_stack_lvl (lib/dump_stack.c:117)
kasan_report (mm/kasan/report.c:603)
kasan_check_range (mm/kasan/generic.c:189)
variable_test_bit (arch/x86/include/asm/bitops.h:227) [inline]
arch_test_bit (arch/x86/include/asm/bitops.h:239) [inline]
_test_bit at (include/asm-generic/bitops/instrumented-non-atomic.h:142) [inline]
node_state (include/linux/nodemask.h:423) [inline]
map_benchmark_ioctl (kernel/dma/map_benchmark.c:214)
full_proxy_unlocked_ioctl (fs/debugfs/file.c:333)
__x64_sys_ioctl (fs/ioctl.c:890)
do_syscall_64 (arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Compare node ids with sane bounds first. NUMA_NO_NODE is considered a
special valid case meaning that benchmarking kthreads won't be bound to a
cpuset of a given node.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 65789daa8087 ("dma-mapping: add benchmark support for streaming DMA APIs")
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:52 +02:00
Fedor Pchelkin
856dc7eb7f dma-mapping: benchmark: fix up kthread-related error handling
[ Upstream commit bb9025f4432f8c158322cf2c04c2b492f23eb511 ]

kthread creation failure is invalidly handled inside do_map_benchmark().
The put_task_struct() calls on the error path are supposed to balance the
get_task_struct() calls which only happen after all the kthreads are
successfully created. Rollback using kthread_stop() for already created
kthreads in case of such failure.

In normal situation call kthread_stop_put() to gracefully stop kthreads
and put their task refcounts. This should be done for all started
kthreads.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 65789daa8087 ("dma-mapping: add benchmark support for streaming DMA APIs")
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:52 +02:00
Andreas Gruenbacher
a9da6ddaef kthread: add kthread_stop_put
[ Upstream commit 6309727ef27162deabd5c095c11af24970fba5a2 ]

Add a kthread_stop_put() helper that stops a thread and puts its task
struct.  Use it to replace the various instances of kthread_stop()
followed by put_task_struct().

Remove the kthread_stop_put() macro in usbip that is similar but doesn't
return the result of kthread_stop().

[agruenba@redhat.com: fix kerneldoc comment]
  Link: https://lkml.kernel.org/r/20230911111730.2565537-1-agruenba@redhat.com
[akpm@linux-foundation.org: document kthread_stop_put()'s argument]
Link: https://lkml.kernel.org/r/20230907234048.2499820-1-agruenba@redhat.com
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: bb9025f4432f ("dma-mapping: benchmark: fix up kthread-related error handling")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:52 +02:00
Carlos López
ad4b202da2 tracing/probes: fix error check in parse_btf_field()
[ Upstream commit e569eb34970281438e2b48a3ef11c87459fcfbcb ]

btf_find_struct_member() might return NULL or an error via the
ERR_PTR() macro. However, its caller in parse_btf_field() only checks
for the NULL condition. Fix this by using IS_ERR() and returning the
error up the stack.

Link: https://lore.kernel.org/all/20240527094351.15687-1-clopez@suse.de/

Fixes: c440adfbe3025 ("tracing/probes: Support BTF based data structure field access")
Signed-off-by: Carlos López <clopez@suse.de>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:51 +02:00
Yang Li
c5caa03d86 rv: Update rv_en(dis)able_monitor doc to match kernel-doc
[ Upstream commit 1e8b7b3dbb3103d577a586ca72bc329f7b67120b ]

The patch updates the function documentation comment for
rv_en(dis)able_monitor to adhere to the kernel-doc specification.

Link: https://lore.kernel.org/linux-trace-kernel/20240520054239.61784-1-yang.lee@linux.alibaba.com

Fixes: 102227b970a15 ("rv: Add Runtime Verification (RV) interface")
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:49 +02:00
Steven Rostedt (Google)
14aa4f3efc eventfs/tracing: Add callback for release of an eventfs_inode
[ Upstream commit b63db58e2fa5d6963db9c45df88e60060f0ff35f ]

Synthetic events create and destroy tracefs files when they are created
and removed. The tracing subsystem has its own file descriptor
representing the state of the events attached to the tracefs files.
There's a race between the eventfs files and this file descriptor of the
tracing system where the following can cause an issue:

With two scripts 'A' and 'B' doing:

  Script 'A':
    echo "hello int aaa" > /sys/kernel/tracing/synthetic_events
    while :
    do
      echo 0 > /sys/kernel/tracing/events/synthetic/hello/enable
    done

  Script 'B':
    echo > /sys/kernel/tracing/synthetic_events

Script 'A' creates a synthetic event "hello" and then just writes zero
into its enable file.

Script 'B' removes all synthetic events (including the newly created
"hello" event).

What happens is that the opening of the "enable" file has:

 {
	struct trace_event_file *file = inode->i_private;
	int ret;

	ret = tracing_check_open_get_tr(file->tr);
 [..]

But deleting the events frees the "file" descriptor, and a "use after
free" happens with the dereference at "file->tr".

The file descriptor does have a reference counter, but there needs to be a
way to decrement it from the eventfs when the eventfs_inode is removed
that represents this file descriptor.

Add an optional "release" callback to the eventfs_entry array structure,
that gets called when the eventfs file is about to be removed. This allows
for the creating on the eventfs file to increment the tracing file
descriptor ref counter. When the eventfs file is deleted, it can call the
release function that will call the put function for the tracing file
descriptor.

This will protect the tracing file from being freed while a eventfs file
that references it is being opened.

Link: https://lore.kernel.org/linux-trace-kernel/20240426073410.17154-1-Tze-nan.Wu@mediatek.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240502090315.448cba46@gandalf.local.home

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 5790b1fb3d672 ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Tze-nan wu <Tze-nan.Wu@mediatek.com>
Tested-by: Tze-nan Wu (吳澤南) <Tze-nan.Wu@mediatek.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:35 +02:00
Cheng Yu
941e1c6d86 sched/core: Fix incorrect initialization of the 'burst' parameter in cpu_max_write()
[ Upstream commit 49217ea147df7647cb89161b805c797487783fc0 ]

In the cgroup v2 CPU subsystem, assuming we have a
cgroup named 'test', and we set cpu.max and cpu.max.burst:

    # echo 1000000 > /sys/fs/cgroup/test/cpu.max
    # echo 1000000 > /sys/fs/cgroup/test/cpu.max.burst

then we check cpu.max and cpu.max.burst:

    # cat /sys/fs/cgroup/test/cpu.max
    1000000 100000
    # cat /sys/fs/cgroup/test/cpu.max.burst
    1000000

Next we set cpu.max again and check cpu.max and
cpu.max.burst:

    # echo 2000000 > /sys/fs/cgroup/test/cpu.max
    # cat /sys/fs/cgroup/test/cpu.max
    2000000 100000

    # cat /sys/fs/cgroup/test/cpu.max.burst
    1000

... we find that the cpu.max.burst value changed unexpectedly.

In cpu_max_write(), the unit of the burst value returned
by tg_get_cfs_burst() is microseconds, while in cpu_max_write(),
the burst unit used for calculation should be nanoseconds,
which leads to the bug.

To fix it, get the burst value directly from tg->cfs_bandwidth.burst.

Fixes: f4183717b370 ("sched/fair: Introduce the burstable CFS controller")
Reported-by: Qixin Liao <liaoqixin@huawei.com>
Signed-off-by: Cheng Yu <serein.chengyu@huawei.com>
Signed-off-by: Zhang Qiao <zhangqiao22@huawei.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20240424132438.514720-1-serein.chengyu@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:13 +02:00
Vitalii Bursov
4d9d099ab2 sched/fair: Allow disabling sched_balance_newidle with sched_relax_domain_level
[ Upstream commit a1fd0b9d751f840df23ef0e75b691fc00cfd4743 ]

Change relax_domain_level checks so that it would be possible
to include or exclude all domains from newidle balancing.

This matches the behavior described in the documentation:

  -1   no request. use system default or follow request of others.
   0   no search.
   1   search siblings (hyperthreads in a core).

"2" enables levels 0 and 1, level_max excludes the last (level_max)
level, and level_max+1 includes all levels.

Fixes: 1d3504fcf560 ("sched, cpuset: customize sched domains, core")
Signed-off-by: Vitalii Bursov <vitaly@bursov.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lore.kernel.org/r/bd6de28e80073c79466ec6401cdeae78f0d4423d.1714488502.git.vitaly@bursov.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:13 +02:00
Beau Belgrave
4aa2d5fd7e tracing/user_events: Fix non-spaced field matching
[ Upstream commit bd125a084091396f3e796bb3dc009940d9771811 ]

When the ABI was updated to prevent same name w/different args, it
missed an important corner case when fields don't end with a space.
Typically, space is used for fields to help separate them, like
"u8 field1; u8 field2". If no spaces are used, like
"u8 field1;u8 field2", then the parsing works for the first time.
However, the match check fails on a subsequent register, leading to
confusion.

This is because the match check uses argv_split() and assumes that all
fields will be split upon the space. When spaces are used, we get back
{ "u8", "field1;" }, without spaces we get back { "u8", "field1;u8" }.
This causes a mismatch, and the user program gets back -EADDRINUSE.

Add a method to detect this case before calling argv_split(). If found
force a space after the field separator character ';'. This ensures all
cases work properly for matching.

With this fix, the following are all treated as matching:
u8 field1;u8 field2
u8 field1; u8 field2
u8 field1;\tu8 field2
u8 field1;\nu8 field2

Link: https://lore.kernel.org/linux-trace-kernel/20240423162338.292-2-beaub@linux.microsoft.com

Fixes: ba470eebc2f6 ("tracing/user_events: Prevent same name but different args event")
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:11 +02:00
Beau Belgrave
4c40e1b76e tracing/user_events: Prepare find/delete for same name events
[ Upstream commit 1e953de9e9b4ca77a9ce0fc17a0778eba3a4ca64 ]

The current code for finding and deleting events assumes that there will
never be cases when user_events are registered with the same name, but
different formats. Scenarios exist where programs want to use the same
name but have different formats. An example is multiple versions of a
program running side-by-side using the same event name, but with updated
formats in each version.

This change does not yet allow for multi-format events. If user_events
are registered with the same name but different arguments the programs
see the same return values as before. This change simply makes it
possible to easily accommodate for this.

Update find_user_event() to take in argument parameters and register
flags to accommodate future multi-format event scenarios. Have find
validate argument matching and return error pointers to cover when
an existing event has the same name but different format. Update
callers to handle error pointer logic.

Move delete_user_event() to use hash walking directly now that
find_user_event() has changed. Delete all events found that match the
register name, stop if an error occurs and report back to the user.

Update user_fields_match() to cover list_empty() scenarios now that
find_user_event() uses it directly. This makes the logic consistent
across several callsites.

Link: https://lore.kernel.org/linux-trace-kernel/20240222001807.1463-2-beaub@linux.microsoft.com

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Stable-dep-of: bd125a084091 ("tracing/user_events: Fix non-spaced field matching")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:11 +02:00
Beau Belgrave
2fc3d0ac09 tracing/user_events: Allow events to persist for perfmon_capable users
[ Upstream commit 5dbd04eddb2c0841d1b3930e0a9944a2343c9cac ]

There are several scenarios that have come up where having a user_event
persist even if the process that registered it exits. The main one is
having a daemon create events on bootup that shouldn't get deleted if
the daemon has to exit or reload. Another is within OpenTelemetry
exporters, they wish to potentially check if a user_event exists on the
system to determine if exporting the data out should occur. The
user_event in this case must exist even in the absence of the owning
process running (such as the above daemon case).

Expose the previously internal flag USER_EVENT_REG_PERSIST to user
processes. Upon register or delete of events with this flag, ensure the
user is perfmon_capable to prevent random user processes with access to
tracefs from creating events that persist after exit.

Link: https://lkml.kernel.org/r/20230912180704.1284-2-beaub@linux.microsoft.com

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Stable-dep-of: bd125a084091 ("tracing/user_events: Fix non-spaced field matching")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:11 +02:00
Kent Overstreet
4c62c6c8a0 kernel/numa.c: Move logging out of numa.h
[ Upstream commit d7a73e3f089204aee3393687e23fd45a22657b08 ]

Moving these stub functions to a .c file means we can kill a sched.h
dependency on printk.h.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Stable-dep-of: f9f67e5adc8d ("x86/numa: Fix SRAT lookup of CFMWS ranges with numa_fill_memblks()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:50 +02:00
Stanislav Fomichev
6675c541f5 bpf: Add BPF_PROG_TYPE_CGROUP_SKB attach type enforcement in BPF_LINK_CREATE
[ Upstream commit 543576ec15b17c0c93301ac8297333c7b6e84ac7 ]

bpf_prog_attach uses attach_type_to_prog_type to enforce proper
attach type for BPF_PROG_TYPE_CGROUP_SKB. link_create uses
bpf_prog_get and relies on bpf_prog_attach_check_attach_type
to properly verify prog_type <> attach_type association.

Add missing attach_type enforcement for the link_create case.
Otherwise, it's currently possible to attach cgroup_skb prog
types to other cgroup hooks.

Fixes: af6eea57437a ("bpf: Implement bpf_link-based cgroup BPF program attachment")
Link: https://lore.kernel.org/bpf/0000000000004792a90615a1dde0@google.com/
Reported-by: syzbot+838346b979830606c854@syzkaller.appspotmail.com
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240426231621.2716876-2-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:48 +02:00
Alexei Starovoitov
39f8a29330 bpf: Fix verifier assumptions about socket->sk
[ Upstream commit 0db63c0b86e981a1e97d2596d64ceceba1a5470e ]

The verifier assumes that 'sk' field in 'struct socket' is valid
and non-NULL when 'socket' pointer itself is trusted and non-NULL.
That may not be the case when socket was just created and
passed to LSM socket_accept hook.
Fix this verifier assumption and adjust tests.

Reported-by: Liam Wisehart <liamwisehart@meta.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Fixes: 6fcd486b3a0a ("bpf: Refactor RCU enforcement in the verifier.")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20240427002544.68803-1-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:47 +02:00
Andrii Nakryiko
b17592380f bpf: prevent r10 register from being marked as precise
[ Upstream commit 1f2a74b41ea8b902687eb97c4e7e3f558801865b ]

r10 is a special register that is not under BPF program's control and is
always effectively precise. The rest of precision logic assumes that
only r0-r9 SCALAR registers are marked as precise, so prevent r10 from
being marked precise.

This can happen due to signed cast instruction allowing to do something
like `r0 = (s8)r10;`, which later, if r0 needs to be precise, would lead
to an attempt to mark r10 as precise.

Prevent this with an extra check during instruction backtracking.

Fixes: 8100928c8814 ("bpf: Support new sign-extension mov insns")
Reported-by: syzbot+148110ee7cf72f39f33e@syzkaller.appspotmail.com
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240404214536.3551295-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:38 +02:00
Shrikanth Hegde
2bd572d421 sched/fair: Add EAS checks before updating root_domain::overutilized
[ Upstream commit be3a51e68f2f1b17250ce40d8872c7645b7a2991 ]

root_domain::overutilized is only used for EAS(energy aware scheduler)
to decide whether to do load balance or not. It is not used if EAS
not possible.

Currently enqueue_task_fair and task_tick_fair accesses, sometime updates
this field. In update_sd_lb_stats it is updated often. This causes cache
contention due to true sharing and burns a lot of cycles. ::overload and
::overutilized are part of the same cacheline. Updating it often invalidates
the cacheline. That causes access to ::overload to slow down due to
false sharing. Hence add EAS check before accessing/updating this field.
EAS check is optimized at compile time or it is a static branch.
Hence it shouldn't cost much.

With the patch, both enqueue_task_fair and newidle_balance don't show
up as hot routines in perf profile.

  6.8-rc4:
  7.18%  swapper          [kernel.vmlinux]              [k] enqueue_task_fair
  6.78%  s                [kernel.vmlinux]              [k] newidle_balance

  +patch:
  0.14%  swapper          [kernel.vmlinux]              [k] enqueue_task_fair
  0.00%  swapper          [kernel.vmlinux]              [k] newidle_balance

While at it: trace_sched_overutilized_tp expect that second argument to
be bool. So do a int to bool conversion for that.

Fixes: 2802bf3cd936 ("sched/fair: Add over-utilization/tipping point indicator")
Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Qais Yousef <qyousef@layalina.io>
Reviewed-by: Srikar Dronamraju <srikar@linux.ibm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20240307085725.444486-2-sshegde@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:37 +02:00
Nikita Kiryushin
afb39909bf rcu: Fix buffer overflow in print_cpu_stall_info()
[ Upstream commit 3758f7d9917bd7ef0482c4184c0ad673b4c4e069 ]

The rcuc-starvation output from print_cpu_stall_info() might overflow the
buffer if there is a huge difference in jiffies difference.  The situation
might seem improbable, but computers sometimes get very confused about
time, which can result in full-sized integers, and, in this case,
buffer overflow.

Also, the unsigned jiffies difference is printed using %ld, which is
normally for signed integers.  This is intentional for debugging purposes,
but it is not obvious from the code.

This commit therefore changes sprintf() to snprintf() and adds a
clarifying comment about intention of %ld format.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 245a62982502 ("rcu: Dump rcuc kthread status for CPUs not reporting quiescent state")
Signed-off-by: Nikita Kiryushin <kiryushin@ancud.ru>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:32 +02:00
Nikita Kiryushin
32d988f48e rcu-tasks: Fix show_rcu_tasks_trace_gp_kthread buffer overflow
[ Upstream commit cc5645fddb0ce28492b15520306d092730dffa48 ]

There is a possibility of buffer overflow in
show_rcu_tasks_trace_gp_kthread() if counters, passed
to sprintf() are huge. Counter numbers, needed for this
are unrealistically high, but buffer overflow is still
possible.

Use snprintf() with buffer size instead of sprintf().

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: edf3775f0ad6 ("rcu-tasks: Add count for idle tasks on offline CPUs")
Signed-off-by: Nikita Kiryushin <kiryushin@ancud.ru>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:32 +02:00
Zqiang
3a83d0d284 softirq: Fix suspicious RCU usage in __do_softirq()
[ Upstream commit 1dd1eff161bd55968d3d46bc36def62d71fb4785 ]

Currently, the condition "__this_cpu_read(ksoftirqd) == current" is used to
invoke rcu_softirq_qs() in ksoftirqd tasks context for non-RT kernels.

This works correctly as long as the context is actually task context but
this condition is wrong when:

     - the current task is ksoftirqd
     - the task is interrupted in a RCU read side critical section
     - __do_softirq() is invoked on return from interrupt

Syzkaller triggered the following scenario:

  -> finish_task_switch()
    -> put_task_struct_rcu_user()
      -> call_rcu(&task->rcu, delayed_put_task_struct)
        -> __kasan_record_aux_stack()
          -> pfn_valid()
            -> rcu_read_lock_sched()
              <interrupt>
                __irq_exit_rcu()
                -> __do_softirq)()
                   -> if (!IS_ENABLED(CONFIG_PREEMPT_RT) &&
                     __this_cpu_read(ksoftirqd) == current)
                     -> rcu_softirq_qs()
                       -> RCU_LOCKDEP_WARN(lock_is_held(&rcu_sched_lock_map))

The rcu quiescent state is reported in the rcu-read critical section, so
the lockdep warning is triggered.

Fix this by splitting out the inner working of __do_softirq() into a helper
function which takes an argument to distinguish between ksoftirqd task
context and interrupted context and invoke it from the relevant call sites
with the proper context information and use that for the conditional
invocation of rcu_softirq_qs().

Reported-by: syzbot+dce04ed6d1438ad69656@syzkaller.appspotmail.com
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240427102808.29356-1-qiang.zhang1211@gmail.com
Link: https://lore.kernel.org/lkml/8f281a10-b85a-4586-9586-5bbc12dc784f@paulmck-laptop/T/#mea8aba4abfcb97bbf499d169ce7f30c4cff1b0e3
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:27 +02:00
Oleg Nesterov
02580c6afd sched/isolation: Fix boot crash when maxcpus < first housekeeping CPU
[ Upstream commit 257bf89d84121280904800acd25cc2c444c717ae ]

housekeeping_setup() checks cpumask_intersects(present, online) to ensure
that the kernel will have at least one housekeeping CPU after smp_init(),
but this doesn't work if the maxcpus= kernel parameter limits the number of
processors available after bootup.

For example, a kernel with "maxcpus=2 nohz_full=0-2" parameters crashes at
boot time on a virtual machine with 4 CPUs.

Change housekeeping_setup() to use cpumask_first_and() and check that the
returned CPU number is valid and less than setup_max_cpus.

Another corner case is "nohz_full=0" on a machine with a single CPU or with
the maxcpus=1 kernel argument. In this case non_housekeeping_mask is empty
and tick_nohz_full_setup() makes no sense. And indeed, the kernel hits the
WARN_ON(tick_nohz_full_running) in tick_sched_do_timer().

And how should the kernel interpret the "nohz_full=" parameter? It should
be silently ignored, but currently cpulist_parse() happily returns the
empty cpumask and this leads to the same problem.

Change housekeeping_setup() to check cpumask_empty(non_housekeeping_mask)
and do nothing in this case.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20240413141746.GA10008@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:24 +02:00
Sean Christopherson
976b74fa60 cpu: Ignore "mitigations" kernel parameter if CPU_MITIGATIONS=n
[ Upstream commit ce0abef6a1d540acef85068e0e82bdf1fbeeb0e9 ]

Explicitly disallow enabling mitigations at runtime for kernels that were
built with CONFIG_CPU_MITIGATIONS=n, as some architectures may omit code
entirely if mitigations are disabled at compile time.

E.g. on x86, a large pile of Kconfigs are buried behind CPU_MITIGATIONS,
and trying to provide sane behavior for retroactively enabling mitigations
is extremely difficult, bordering on impossible.  E.g. page table isolation
and call depth tracking require build-time support, BHI mitigations will
still be off without additional kernel parameters, etc.

  [ bp: Touchups. ]

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240420000556.2645001-3-seanjc@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:24 +02:00
Petr Pavlu
af3274905b ring-buffer: Fix a race between readers and resize checks
commit c2274b908db05529980ec056359fae916939fdaa upstream.

The reader code in rb_get_reader_page() swaps a new reader page into the
ring buffer by doing cmpxchg on old->list.prev->next to point it to the
new page. Following that, if the operation is successful,
old->list.next->prev gets updated too. This means the underlying
doubly-linked list is temporarily inconsistent, page->prev->next or
page->next->prev might not be equal back to page for some page in the
ring buffer.

The resize operation in ring_buffer_resize() can be invoked in parallel.
It calls rb_check_pages() which can detect the described inconsistency
and stop further tracing:

[  190.271762] ------------[ cut here ]------------
[  190.271771] WARNING: CPU: 1 PID: 6186 at kernel/trace/ring_buffer.c:1467 rb_check_pages.isra.0+0x6a/0xa0
[  190.271789] Modules linked in: [...]
[  190.271991] Unloaded tainted modules: intel_uncore_frequency(E):1 skx_edac(E):1
[  190.272002] CPU: 1 PID: 6186 Comm: cmd.sh Kdump: loaded Tainted: G            E      6.9.0-rc6-default #5 158d3e1e6d0b091c34c3b96bfd99a1c58306d79f
[  190.272011] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552c-rebuilt.opensuse.org 04/01/2014
[  190.272015] RIP: 0010:rb_check_pages.isra.0+0x6a/0xa0
[  190.272023] Code: [...]
[  190.272028] RSP: 0018:ffff9c37463abb70 EFLAGS: 00010206
[  190.272034] RAX: ffff8eba04b6cb80 RBX: 0000000000000007 RCX: ffff8eba01f13d80
[  190.272038] RDX: ffff8eba01f130c0 RSI: ffff8eba04b6cd00 RDI: ffff8eba0004c700
[  190.272042] RBP: ffff8eba0004c700 R08: 0000000000010002 R09: 0000000000000000
[  190.272045] R10: 00000000ffff7f52 R11: ffff8eba7f600000 R12: ffff8eba0004c720
[  190.272049] R13: ffff8eba00223a00 R14: 0000000000000008 R15: ffff8eba067a8000
[  190.272053] FS:  00007f1bd64752c0(0000) GS:ffff8eba7f680000(0000) knlGS:0000000000000000
[  190.272057] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  190.272061] CR2: 00007f1bd6662590 CR3: 000000010291e001 CR4: 0000000000370ef0
[  190.272070] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  190.272073] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  190.272077] Call Trace:
[  190.272098]  <TASK>
[  190.272189]  ring_buffer_resize+0x2ab/0x460
[  190.272199]  __tracing_resize_ring_buffer.part.0+0x23/0xa0
[  190.272206]  tracing_resize_ring_buffer+0x65/0x90
[  190.272216]  tracing_entries_write+0x74/0xc0
[  190.272225]  vfs_write+0xf5/0x420
[  190.272248]  ksys_write+0x67/0xe0
[  190.272256]  do_syscall_64+0x82/0x170
[  190.272363]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  190.272373] RIP: 0033:0x7f1bd657d263
[  190.272381] Code: [...]
[  190.272385] RSP: 002b:00007ffe72b643f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  190.272391] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f1bd657d263
[  190.272395] RDX: 0000000000000002 RSI: 0000555a6eb538e0 RDI: 0000000000000001
[  190.272398] RBP: 0000555a6eb538e0 R08: 000000000000000a R09: 0000000000000000
[  190.272401] R10: 0000555a6eb55190 R11: 0000000000000246 R12: 00007f1bd6662500
[  190.272404] R13: 0000000000000002 R14: 00007f1bd6667c00 R15: 0000000000000002
[  190.272412]  </TASK>
[  190.272414] ---[ end trace 0000000000000000 ]---

Note that ring_buffer_resize() calls rb_check_pages() only if the parent
trace_buffer has recording disabled. Recent commit d78ab792705c
("tracing: Stop current tracer when resizing buffer") causes that it is
now always the case which makes it more likely to experience this issue.

The window to hit this race is nonetheless very small. To help
reproducing it, one can add a delay loop in rb_get_reader_page():

 ret = rb_head_page_replace(reader, cpu_buffer->reader_page);
 if (!ret)
 	goto spin;
 for (unsigned i = 0; i < 1U << 26; i++)  /* inserted delay loop */
 	__asm__ __volatile__ ("" : : : "memory");
 rb_list_head(reader->list.next)->prev = &cpu_buffer->reader_page->list;

.. and then run the following commands on the target system:

 echo 1 > /sys/kernel/tracing/events/sched/sched_switch/enable
 while true; do
 	echo 16 > /sys/kernel/tracing/buffer_size_kb; sleep 0.1
 	echo 8 > /sys/kernel/tracing/buffer_size_kb; sleep 0.1
 done &
 while true; do
 	for i in /sys/kernel/tracing/per_cpu/*; do
 		timeout 0.1 cat $i/trace_pipe; sleep 0.2
 	done
 done

To fix the problem, make sure ring_buffer_resize() doesn't invoke
rb_check_pages() concurrently with a reader operating on the same
ring_buffer_per_cpu by taking its cpu_buffer->reader_lock.

Link: https://lore.kernel.org/linux-trace-kernel/20240517134008.24529-3-petr.pavlu@suse.com

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 659f451ff213 ("ring-buffer: Add integrity check at end of iter read")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
[ Fixed whitespace ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-12 11:11:19 +02:00
Zheng Yejian
7b4881da5b ftrace: Fix possible use-after-free issue in ftrace_location()
commit e60b613df8b6253def41215402f72986fee3fc8d upstream.

KASAN reports a bug:

  BUG: KASAN: use-after-free in ftrace_location+0x90/0x120
  Read of size 8 at addr ffff888141d40010 by task insmod/424
  CPU: 8 PID: 424 Comm: insmod Tainted: G        W          6.9.0-rc2+
  [...]
  Call Trace:
   <TASK>
   dump_stack_lvl+0x68/0xa0
   print_report+0xcf/0x610
   kasan_report+0xb5/0xe0
   ftrace_location+0x90/0x120
   register_kprobe+0x14b/0xa40
   kprobe_init+0x2d/0xff0 [kprobe_example]
   do_one_initcall+0x8f/0x2d0
   do_init_module+0x13a/0x3c0
   load_module+0x3082/0x33d0
   init_module_from_file+0xd2/0x130
   __x64_sys_finit_module+0x306/0x440
   do_syscall_64+0x68/0x140
   entry_SYSCALL_64_after_hwframe+0x71/0x79

The root cause is that, in lookup_rec(), ftrace record of some address
is being searched in ftrace pages of some module, but those ftrace pages
at the same time is being freed in ftrace_release_mod() as the
corresponding module is being deleted:

           CPU1                       |      CPU2
  register_kprobes() {                | delete_module() {
    check_kprobe_address_safe() {     |
      arch_check_ftrace_location() {  |
        ftrace_location() {           |
          lookup_rec() // USE!        |   ftrace_release_mod() // Free!

To fix this issue:
  1. Hold rcu lock as accessing ftrace pages in ftrace_location_range();
  2. Use ftrace_location_range() instead of lookup_rec() in
     ftrace_location();
  3. Call synchronize_rcu() before freeing any ftrace pages both in
     ftrace_process_locs()/ftrace_release_mod()/ftrace_free_mem().

Link: https://lore.kernel.org/linux-trace-kernel/20240509192859.1273558-1-zhengyejian1@huawei.com

Cc: stable@vger.kernel.org
Cc: <mhiramat@kernel.org>
Cc: <mark.rutland@arm.com>
Cc: <mathieu.desnoyers@efficios.com>
Fixes: ae6aa16fdc16 ("kprobes: introduce ftrace based optimization")
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-12 11:11:17 +02:00
Sven Schnelle
c57824d4fe workqueue: Fix selection of wake_cpu in kick_pool()
commit 57a01eafdcf78f6da34fad9ff075ed5dfdd9f420 upstream.

With cpu_possible_mask=0-63 and cpu_online_mask=0-7 the following
kernel oops was observed:

smp: Bringing up secondary CPUs ...
smp: Brought up 1 node, 8 CPUs
Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0000000000000000 TEID: 0000000000000803
[..]
 Call Trace:
arch_vcpu_is_preempted+0x12/0x80
select_idle_sibling+0x42/0x560
select_task_rq_fair+0x29a/0x3b0
try_to_wake_up+0x38e/0x6e0
kick_pool+0xa4/0x198
__queue_work.part.0+0x2bc/0x3a8
call_timer_fn+0x36/0x160
__run_timers+0x1e2/0x328
__run_timer_base+0x5a/0x88
run_timer_softirq+0x40/0x78
__do_softirq+0x118/0x388
irq_exit_rcu+0xc0/0xd8
do_ext_irq+0xae/0x168
ext_int_handler+0xbe/0xf0
psw_idle_exit+0x0/0xc
default_idle_call+0x3c/0x110
do_idle+0xd4/0x158
cpu_startup_entry+0x40/0x48
rest_init+0xc6/0xc8
start_kernel+0x3c4/0x5e0
startup_continue+0x3c/0x50

The crash is caused by calling arch_vcpu_is_preempted() for an offline
CPU. To avoid this, select the cpu with cpumask_any_and_distribute()
to mask __pod_cpumask with cpu_online_mask. In case no cpu is left in
the pool, skip the assignment.

tj: This doesn't fully fix the bug as CPUs can still go down between picking
the target CPU and the wake call. Fixing that likely requires adding
cpu_online() test to either the sched or s390 arch code. However, regardless
of how that is fixed, workqueue shouldn't be picking a CPU which isn't
online as that would result in unpredictable and worse behavior.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Fixes: 8639ecebc9b1 ("workqueue: Implement non-strict affinity scope for unbound workqueues")
Cc: stable@vger.kernel.org # v6.6+
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-17 12:02:31 +02:00
Andrei Matei
608e13706c bpf: Check bloom filter map value size
[ Upstream commit a8d89feba7e54e691ca7c4efc2a6264fa83f3687 ]

This patch adds a missing check to bloom filter creating, rejecting
values above KMALLOC_MAX_SIZE. This brings the bloom map in line with
many other map types.

The lack of this protection can cause kernel crashes for value sizes
that overflow int's. Such a crash was caught by syzkaller. The next
patch adds more guard-rails at a lower level.

Signed-off-by: Andrei Matei <andreimatei1@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240327024245.318299-2-andreimatei1@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 12:02:11 +02:00
Will Deacon
f2a6b3ed20 swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y
[ Upstream commit 75961ffb5cb3e5196f19cae7683f35cc88b50800 ]

Using restricted DMA pools (CONFIG_DMA_RESTRICTED_POOL=y) in conjunction
with dynamic SWIOTLB (CONFIG_SWIOTLB_DYNAMIC=y) leads to the following
crash when initialising the restricted pools at boot-time:

  | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
  | Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
  | pc : rmem_swiotlb_device_init+0xfc/0x1ec
  | lr : rmem_swiotlb_device_init+0xf0/0x1ec
  | Call trace:
  |  rmem_swiotlb_device_init+0xfc/0x1ec
  |  of_reserved_mem_device_init_by_idx+0x18c/0x238
  |  of_dma_configure_id+0x31c/0x33c
  |  platform_dma_configure+0x34/0x80

faddr2line reveals that the crash is in the list validation code:

  include/linux/list.h:83
  include/linux/rculist.h:79
  include/linux/rculist.h:106
  kernel/dma/swiotlb.c:306
  kernel/dma/swiotlb.c:1695

because add_mem_pool() is trying to list_add_rcu() to a NULL
'mem->pools'.

Fix the crash by initialising the 'mem->pools' list_head in
rmem_swiotlb_device_init() before calling add_mem_pool().

Reported-by: Nikita Ioffe <ioffe@google.com>
Tested-by: Nikita Ioffe <ioffe@google.com>
Fixes: 1aaa736815eb ("swiotlb: allocate a new memory pool when existing pools are full")
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 12:02:08 +02:00
Anton Protopopov
fe4bfff1cd bpf: Fix a verifier verbose message
[ Upstream commit 37eacb9f6e89fb399a79e952bc9c78eb3e16290e ]

Long ago a map file descriptor in a pseudo ldimm64 instruction could
only be present as an immediate value insn[0].imm, and thus this value
was used in a verbose verifier message printed when the file descriptor
wasn't valid. Since addition of BPF_PSEUDO_MAP_IDX_VALUE/BPF_PSEUDO_MAP_IDX
the insn[0].imm field can also contain an index pointing to the file
descriptor in the attr.fd_array array. However, if the file descriptor
is invalid, the verifier still prints the verbose message containing
value of insn[0].imm. Patch the verifier message to always print the
actual file descriptor value.

Fixes: 387544bfa291 ("bpf: Introduce fd_idx")
Signed-off-by: Anton Protopopov <aspsk@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240412141100.3562942-1-aspsk@isovalent.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 12:02:00 +02:00
Matthew Wilcox (Oracle)
15aa09d6d8 bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS
commit 5af385f5f4cddf908f663974847a4083b2ff2c79 upstream.

bits_per() rounds up to the next power of two when passed a power of
two.  This causes crashes on some machines and configurations.

Reported-by: Михаил Новоселов <m.novosyolov@rosalinux.ru>
Tested-by: Ильфат Гаптрахманов <i.gaptrakhmanov@rosalinux.ru>
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3347
Link: https://lore.kernel.org/all/1c978cf1-2934-4e66-e4b3-e81b04cb3571@rosalinux.ru/
Fixes: f2d5dcb48f7b (bounds: support non-power-of-two CONFIG_NR_CPUS)
Cc:  <stable@vger.kernel.org>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-02 16:32:50 +02:00