linux.git/kernel, branch v6.1.92

timers: Rename del_timer() to timer_delete()

2024-05-17T09:56:13+00:00

[ Upstream commit bb663f0f3c396c6d05f6c5eeeea96ced20ff112e ]

The timer related functions do not have a strict timer_ prefixed namespace
which is really annoying.

Rename del_timer() to timer_delete() and provide del_timer()
as a wrapper. Document that del_timer() is not for new code.

Signed-off-by: Thomas Gleixner 
Tested-by: Guenter Roeck 
Reviewed-by: Steven Rostedt (Google) 
Reviewed-by: Jacob Keller 
Reviewed-by: Anna-Maria Behnsen 
Link: https://lore.kernel.org/r/20221123201625.015535022@linutronix.de
Stable-dep-of: 4893b8b3ef8d ("hsr: Simplify code for announcing HSR nodes timer setup")
Signed-off-by: Sasha Levin

timers: Get rid of del_singleshot_timer_sync()

2024-05-17T09:56:12+00:00

[ Upstream commit 9a5a305686971f4be10c6d7251c8348d74b3e014 ]

del_singleshot_timer_sync() used to be an optimization for deleting timers
which are not rearmed from the timer callback function.

This optimization turned out to be broken and got mapped to
del_timer_sync() about 17 years ago.

Get rid of the undocumented indirection and use del_timer_sync() directly.

No functional change.

Signed-off-by: Thomas Gleixner 
Tested-by: Guenter Roeck 
Reviewed-by: Jacob Keller 
Reviewed-by: Anna-Maria Behnsen 
Link: https://lore.kernel.org/r/20221123201624.706987932@linutronix.de
Stable-dep-of: 4893b8b3ef8d ("hsr: Simplify code for announcing HSR nodes timer setup")
Signed-off-by: Sasha Levin

bpf: Check bloom filter map value size

2024-05-17T09:56:05+00:00

[ 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 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/r/20240327024245.318299-2-andreimatei1@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

bpf: Fix a verifier verbose message

2024-05-17T09:55:56+00:00

[ 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 
Signed-off-by: Daniel Borkmann 
Acked-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20240412141100.3562942-1-aspsk@isovalent.com
Signed-off-by: Sasha Levin

bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS

2024-05-02T14:29:32+00:00

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 
Tested-by: Ильфат Гаптрахманов 
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:  
Signed-off-by: Matthew Wilcox (Oracle) 
Cc: Rik van Riel 
Cc: Mel Gorman 
Cc: Peter Zijlstra 
Cc: Ingo Molnar 
Cc: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

cpu: Re-enable CPU mitigations by default for !X86 architectures

2024-05-02T14:29:28+00:00

commit fe42754b94a42d08cf9501790afc25c4f6a5f631 upstream.

Rename x86's to CPU_MITIGATIONS, define it in generic code, and force it
on for all architectures exception x86.  A recent commit to turn
mitigations off by default if SPECULATION_MITIGATIONS=n kinda sorta
missed that "cpu_mitigations" is completely generic, whereas
SPECULATION_MITIGATIONS is x86-specific.

Rename x86's SPECULATIVE_MITIGATIONS instead of keeping both and have it
select CPU_MITIGATIONS, as having two configs for the same thing is
unnecessary and confusing.  This will also allow x86 to use the knob to
manage mitigations that aren't strictly related to speculative
execution.

Use another Kconfig to communicate to common code that CPU_MITIGATIONS
is already defined instead of having x86's menu depend on the common
CPU_MITIGATIONS.  This allows keeping a single point of contact for all
of x86's mitigations, and it's not clear that other architectures *want*
to allow disabling mitigations at compile-time.

Fixes: f337a6a21e2f ("x86/cpu: Actually turn off mitigations by default for SPECULATION_MITIGATIONS=n")
Closes: https://lkml.kernel.org/r/20240413115324.53303a68%40canb.auug.org.au
Reported-by: Stephen Rothwell 
Reported-by: Michael Ellerman 
Reported-by: Geert Uytterhoeven 
Signed-off-by: Sean Christopherson 
Signed-off-by: Borislav Petkov (AMD) 
Acked-by: Josh Poimboeuf 
Acked-by: Borislav Petkov (AMD) 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240420000556.2645001-2-seanjc@google.com
Signed-off-by: Greg Kroah-Hartman

fork: defer linking file vma until vma is fully initialized

2024-05-02T14:29:27+00:00

commit 35e351780fa9d8240dd6f7e4f245f9ea37e96c19 upstream.

Thorvald reported a WARNING [1]. And the root cause is below race:

 CPU 1					CPU 2
 fork					hugetlbfs_fallocate
  dup_mmap				 hugetlbfs_punch_hole
   i_mmap_lock_write(mapping);
   vma_interval_tree_insert_after -- Child vma is visible through i_mmap tree.
   i_mmap_unlock_write(mapping);
   hugetlb_dup_vma_private -- Clear vma_lock outside i_mmap_rwsem!
					 i_mmap_lock_write(mapping);
   					 hugetlb_vmdelete_list
					  vma_interval_tree_foreach
					   hugetlb_vma_trylock_write -- Vma_lock is cleared.
   tmp->vm_ops->open -- Alloc new vma_lock outside i_mmap_rwsem!
					   hugetlb_vma_unlock_write -- Vma_lock is assigned!!!
					 i_mmap_unlock_write(mapping);

hugetlb_dup_vma_private() and hugetlb_vm_op_open() are called outside
i_mmap_rwsem lock while vma lock can be used in the same time.  Fix this
by deferring linking file vma until vma is fully initialized.  Those vmas
should be initialized first before they can be used.

Link: https://lkml.kernel.org/r/20240410091441.3539905-1-linmiaohe@huawei.com
Fixes: 8d9bfb260814 ("hugetlb: add vma based lock for pmd sharing")
Signed-off-by: Miaohe Lin 
Reported-by: Thorvald Natvig 
Closes: https://lore.kernel.org/linux-mm/20240129161735.6gmjsswx62o4pbja@revolver/T/ [1]
Reviewed-by: Jane Chu 
Cc: Christian Brauner 
Cc: Heiko Carstens 
Cc: Kent Overstreet 
Cc: Liam R. Howlett 
Cc: Mateusz Guzik 
Cc: Matthew Wilcox (Oracle) 
Cc: Miaohe Lin 
Cc: Muchun Song 
Cc: Oleg Nesterov 
Cc: Peng Zhang 
Cc: Tycho Andersen 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Miaohe Lin 
Signed-off-by: Greg Kroah-Hartman

x86/cpu: Actually turn off mitigations by default for SPECULATION_MITIGATIONS=n

2024-04-17T09:18:27+00:00

commit f337a6a21e2fd67eadea471e93d05dd37baaa9be upstream.

Initialize cpu_mitigations to CPU_MITIGATIONS_OFF if the kernel is built
with CONFIG_SPECULATION_MITIGATIONS=n, as the help text quite clearly
states that disabling SPECULATION_MITIGATIONS is supposed to turn off all
mitigations by default.

  │ If you say N, all mitigations will be disabled. You really
  │ should know what you are doing to say so.

As is, the kernel still defaults to CPU_MITIGATIONS_AUTO, which results in
some mitigations being enabled in spite of SPECULATION_MITIGATIONS=n.

Fixes: f43b9876e857 ("x86/retbleed: Add fine grained Kconfig knobs")
Signed-off-by: Sean Christopherson 
Signed-off-by: Ingo Molnar 
Reviewed-by: Daniel Sneddon 
Cc: stable@vger.kernel.org
Cc: Linus Torvalds 
Link: https://lore.kernel.org/r/20240409175108.1512861-2-seanjc@google.com
Signed-off-by: Greg Kroah-Hartman

kprobes: Fix possible use-after-free issue on kprobe registration

2024-04-17T09:18:27+00:00

commit 325f3fb551f8cd672dbbfc4cf58b14f9ee3fc9e8 upstream.

When unloading a module, its state is changing MODULE_STATE_LIVE ->
 MODULE_STATE_GOING -> MODULE_STATE_UNFORMED. Each change will take
a time. `is_module_text_address()` and `__module_text_address()`
works with MODULE_STATE_LIVE and MODULE_STATE_GOING.
If we use `is_module_text_address()` and `__module_text_address()`
separately, there is a chance that the first one is succeeded but the
next one is failed because module->state becomes MODULE_STATE_UNFORMED
between those operations.

In `check_kprobe_address_safe()`, if the second `__module_text_address()`
is failed, that is ignored because it expected a kernel_text address.
But it may have failed simply because module->state has been changed
to MODULE_STATE_UNFORMED. In this case, arm_kprobe() will try to modify
non-exist module text address (use-after-free).

To fix this problem, we should not use separated `is_module_text_address()`
and `__module_text_address()`, but use only `__module_text_address()`
once and do `try_module_get(module)` which is only available with
MODULE_STATE_LIVE.

Link: https://lore.kernel.org/all/20240410015802.265220-1-zhengyejian1@huawei.com/

Fixes: 28f6c37a2910 ("kprobes: Forbid probing on trampoline and BPF code areas")
Cc: stable@vger.kernel.org
Signed-off-by: Zheng Yejian 
Signed-off-by: Masami Hiramatsu (Google) 
Signed-off-by: Greg Kroah-Hartman

tracing: hide unused ftrace_event_id_fops

2024-04-17T09:18:26+00:00

[ Upstream commit 5281ec83454d70d98b71f1836fb16512566c01cd ]

When CONFIG_PERF_EVENTS, a 'make W=1' build produces a warning about the
unused ftrace_event_id_fops variable:

kernel/trace/trace_events.c:2155:37: error: 'ftrace_event_id_fops' defined but not used [-Werror=unused-const-variable=]
 2155 | static const struct file_operations ftrace_event_id_fops = {

Hide this in the same #ifdef as the reference to it.

Link: https://lore.kernel.org/linux-trace-kernel/20240403080702.3509288-7-arnd@kernel.org

Cc: Masami Hiramatsu 
Cc: Oleg Nesterov 
Cc: Mathieu Desnoyers 
Cc: Zheng Yejian 
Cc: Kees Cook 
Cc: Ajay Kaher 
Cc: Jinjie Ruan 
Cc: Clément Léger 
Cc: Dan Carpenter 
Cc: "Tzvetomir Stoyanov (VMware)" 
Fixes: 620a30e97feb ("tracing: Don't pass file_operations array to event_create_dir()")
Signed-off-by: Arnd Bergmann 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Sasha Levin