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x86/module: rework ROX cache to avoid writable copy#45

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x86/module: rework ROX cache to avoid writable copy#45
modules-kpd-app[bot] wants to merge 39 commits intomodules-next_basefrom
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Pull request for series with
subject: x86/module: rework ROX cache to avoid writable copy
version: 1
url: https://patchwork.kernel.org/project/linux-modules/list/?series=921069

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Upstream branch: 8a231a1
series: https://patchwork.kernel.org/project/linux-modules/list/?series=921069
version: 1

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modules-kpd-app bot commented Jan 6, 2025

Upstream branch: b7e6013
series: https://patchwork.kernel.org/project/linux-modules/list/?series=921069
version: 1

@modules-kpd-app modules-kpd-app bot force-pushed the series/921069=>modules-next branch from cb90bda to 2336945 Compare January 6, 2025 13:58
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modules-kpd-app bot commented Jan 15, 2025

Upstream branch: 0217859
series: https://patchwork.kernel.org/project/linux-modules/list/?series=921069
version: 1

@modules-kpd-app modules-kpd-app bot force-pushed the series/921069=>modules-next branch from 2336945 to d781cd1 Compare January 15, 2025 19:55
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modules-kpd-app bot commented Jan 28, 2025

Upstream branch: f3b9354
series: https://patchwork.kernel.org/project/linux-modules/list/?series=928370
version: 3

@modules-kpd-app modules-kpd-app bot added V3 and removed V1 labels Jan 28, 2025
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Upstream branch: f3b9354
series: https://patchwork.kernel.org/project/linux-modules/list/?series=928370
version: 3

@modules-kpd-app modules-kpd-app bot force-pushed the series/921069=>modules-next branch from b33b80a to 292b114 Compare January 28, 2025 10:36
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Upstream branch: 48ecfdd
series: https://patchwork.kernel.org/project/linux-modules/list/?series=928370
version: 3

@modules-kpd-app modules-kpd-app bot force-pushed the series/921069=>modules-next branch from 292b114 to 34796b9 Compare January 30, 2025 13:44
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Upstream branch: 053842e
series: https://patchwork.kernel.org/project/linux-modules/list/?series=928370
version: 3

@modules-kpd-app modules-kpd-app bot force-pushed the series/921069=>modules-next branch from 34796b9 to c534b53 Compare February 4, 2025 12:19
Joelgranados and others added 7 commits February 17, 2025 10:43
@Joelgranados @petrpavlu
tests/module: nix-ify
7ae75c7 
Use "#!/usr/bin/env bash" instead of "#!/bin/bash". This is necessary
for nix environments as they only provide /usr/bin/env at the standard
location.

Signed-off-by: Joel Granados <joel.granados@kernel.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20250122-jag-nix-ify-v1-1-addb3170f93c@kernel.org
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
module: Begin to move from RCU-sched to RCU.
4ac0446 
The RCU usage in module was introduced in commit d72b375 ("Remove
stop_machine during module load v2") and it claimed not to be RCU but
similar. Then there was another improvement in commit e91defa
("module: don't use stop_machine on module load"). It become a mix of
RCU and RCU-sched and was eventually fixed 0be964b ("module:
Sanitize RCU usage and locking"). Later RCU & RCU-sched was merged in
commit cb2f553 ("modules: Replace synchronize_sched() and
call_rcu_sched()") so that was aligned.

Looking at it today, there is still leftovers. The preempt_disable() was
used instead rcu_read_lock_sched(). The RCU & RCU-sched merge was not
complete as there is still rcu_dereference_sched() for module::kallsyms.

The RCU-list modules and unloaded_tainted_modules are always accessed
under RCU protection or the module_mutex. The modules list iteration can
always happen safely because the module will not disappear.
Once the module is removed (free_module()) then after removing the
module from the list, there is a synchronize_rcu() which waits until
every RCU reader left the section. That means iterating over the list
within a RCU-read section is enough, there is no need to disable
preemption. module::kallsyms is first assigned in add_kallsyms() before
the module is added to the list. At this point, it points to init data.
This pointer is later updated and before the init code is removed there
is also synchronize_rcu() in do_free_init(). That means A RCU read lock
is enough for protection and rcu_dereference() can be safely used.

Convert module code and its users step by step. Update comments and
convert print_modules() to use RCU.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-3-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
module: Use proper RCU assignment in add_kallsyms().
58f0364 
add_kallsyms() assigns the RCU pointer module::kallsyms and setups the
structures behind it which point to init-data. The module was not
published yet, nothing can see the kallsyms pointer and the data behind
it. Also module's init function was not yet invoked.
There is no need to use rcu_dereference() here, it is just to keep
checkers quiet. The whole RCU read section is also not needed.

Use a local kallsyms pointer and setup the data structures. Assign that
pointer to the data structure at the end via rcu_assign_pointer().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-4-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
module: Use RCU in find_kallsyms_symbol().
dd19935 
The modules list and module::kallsyms can be accessed under RCU
assumption.

Use rcu_dereference() to reference the kallsyms pointer in
find_kallsyms_symbol().  Use a RCU section instead of preempt_disable in
callers of find_kallsyms_symbol(). Keep the preempt-disable in
module_address_lookup() due to __module_address().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-5-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
module: Use RCU in module_get_kallsym().
ea3bb68 
The modules list and module::kallsyms can be accessed under RCU
assumption.

Iterate the modules with RCU protection, use rcu_dereference() to access
the kallsyms pointer.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-6-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
module: Use RCU in find_module_all().
3d8628d 
The modules list and module::kallsyms can be accessed under RCU
assumption.

Remove module_assert_mutex_or_preempt() from find_module_all() so it can
be used under RCU protection without warnings. Update its callers to use
RCU protection instead of preempt_disable().

Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-trace-kernel@vger.kernel.org
Cc: live-patching@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250108090457.512198-7-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
module: Use RCU in __find_kallsyms_symbol_value().
4fa1035 
module::kallsyms can be accessed under RCU assumption.

Use rcu_dereference() to access module::kallsyms.
Update callers.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-8-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Sebastian Andrzej Siewior and others added 11 commits February 17, 2025 10:43
@petrpavlu
powerpc/ftrace: Use RCU in all users of __module_text_address().
8d287fd 
__module_text_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_text_address()
with RCU.

Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-trace-kernel@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Link: https://lore.kernel.org/r/20250108090457.512198-21-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
cfi: Use RCU while invoking __module_address().
70798b9 
__module_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

The _notrace() variant was introduced in commit 14c4c8e ("cfi: Use
rcu_read_{un}lock_sched_notrace"). The recursive case where
__cfi_slowpath_diag() could end up calling itself is no longer present,
as all that logic is gone since commit 8924560 ("cfi: Switch to
-fsanitize=kcfi").
Sami Tolvanen said that KCFI checks don't perform function calls.

Elliot Berman verified it with
| modprobe -a dummy_stm stm_ftrace stm_p_basic
| mkdir -p /sys/kernel/config/stp-policy/dummy_stm.0.my-policy/default
| echo function > /sys/kernel/tracing/current_tracer
| echo 1 > /sys/kernel/tracing/tracing_on
| echo dummy_stm.0 > /sys/class/stm_source/ftrace/stm_source_link

Replace the rcu_read_lock_sched_notrace() section around
__module_address() with RCU.

Cc: Elliot Berman <quic_eberman@quicinc.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: llvm@lists.linux.dev
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Elliot Berman <elliot.berman@oss.qualcomm.com>  # sm8650-qrd [1]
Link: https://lore.kernel.org/all/20241230185812429-0800.eberman@hu-eberman-lv.qualcomm.com [1]
Link: https://lore.kernel.org/r/20250108090457.512198-22-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
x86: Use RCU in all users of __module_address().
e9d25b4 
__module_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_address() with
RCU.

Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-23-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
jump_label: Use RCU in all users of __module_address().
541895c 
__module_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_address() with RCU.

Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-24-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
jump_label: Use RCU in all users of __module_text_address().
762d22f 
__module_text_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_text_address()
with RCU.

Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-25-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
bpf: Use RCU in all users of __module_text_address().
6e263b4 
__module_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_address() with
RCU.

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matt Bobrowski <mattbobrowski@google.com>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: bpf@vger.kernel.org
Cc: linux-trace-kernel@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20250129084751.tH6iidUO@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
kprobes: Use RCU in all users of __module_text_address().
9446f28 
__module_text_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_text_address()
with RCU.

Cc: David S. Miller <davem@davemloft.net>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: linux-trace-kernel@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250129084925.9ppBjGLC@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
static_call: Use RCU in all users of __module_text_address().
f480f04 
__module_text_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_text_address()
with RCU.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-28-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@petrpavlu
bug: Use RCU instead RCU-sched to protect module_bug_list.
3a2ef09 
The list module_bug_list relies on module_mutex for writer
synchronisation. The list is already RCU style.
The list removal is synchronized with modules' synchronize_rcu() in
free_module().

Use RCU read lock protection instead of RCU-sched.

Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250108090457.512198-29-bigeasy@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@toblux @petrpavlu
params: Annotate struct module_param_attrs with __counted_by()
afa9286 
Add the __counted_by compiler attribute to the flexible array member
attrs to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.

Increment num before adding a new param_attribute to the attrs array and
adjust the array index accordingly. Increment num immediately after the
first reallocation such that the reallocation for the NULL terminator
only needs to add 1 (instead of 2) to mk->mp->num.

Use struct_size() instead of manually calculating the size for the
reallocation.

Use krealloc_array() for the additional NULL terminator.

Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20250213221352.2625-3-thorsten.blum@linux.dev
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
@mcgrof
adding ci files
b5b7508
rppt and others added 9 commits February 17, 2025 10:03
@rppt @mcgrof
x86/mm/pat: cpa-test: fix length for CPA_ARRAY test
f7d66d8 
The CPA_ARRAY test always uses len[1] as numpages argument to
change_page_attr_set() although the addresses array is different each
iteration of the test loop.

Replace len[1] with len[i] to have numpages matching the addresses array.

Fixes: ecc729f ("x86/mm/cpa: Add ARRAY and PAGES_ARRAY selftests")
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
@rppt @mcgrof
x86/mm/pat: drop duplicate variable in cpa_flush()
8bfdea7 
There is a 'struct cpa_data *data' parameter in cpa_flush() that is
assigned to a local 'struct cpa_data *cpa' variable.

Rename the parameter from 'data' to 'cpa' and drop declaration of the
local 'cpa' variable.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
@kiryl @mcgrof
x86/mm/pat: restore large ROX pages after fragmentation
fd19851 
Change of attributes of the pages may lead to fragmentation of direct
mapping over time and performance degradation when these pages contain
executable code.

With current code it's one way road: kernel tries to avoid splitting
large pages, but it doesn't restore them back even if page attributes
got compatible again.

Any change to the mapping may potentially allow to restore large page.

Add a hook to cpa_flush() path that will check if the pages in the range
that were just touched can be mapped at PMD level. If the collapse at the
PMD level succeeded, also attempt to collapse PUD level.

The collapse logic runs only when a set_memory_ method explicitly sets
CPA_COLLAPSE flag, for now this is only enabled in set_memory_rox().

CPUs don't like[1] to have to have TLB entries of different size for the
same memory, but looks like it's okay as long as these entries have
matching attributes[2]. Therefore it's critical to flush TLB before any
following changes to the mapping.

Note that we already allow for multiple TLB entries of different sizes
for the same memory now in split_large_page() path. It's not a new
situation.

set_memory_4k() provides a way to use 4k pages on purpose. Kernel must
not remap such pages as large. Re-use one of software PTE bits to
indicate such pages.

[1] See Erratum 383 of AMD Family 10h Processors
[2] https://lore.kernel.org/linux-mm/1da1b025-cabc-6f04-bde5-e50830d1ecf0@amd.com/

[rppt@kernel.org:
 * s/restore/collapse/
 * update formatting per peterz
 * use 'struct ptdesc' instead of 'struct page' for list of page tables to
   be freed
 * try to collapse PMD first and if it succeeds move on to PUD as peterz
   suggested
 * flush TLB twice: for changes done in the original CPA call and after
   collapsing of large pages
 * update commit message
]

Link: https://lore.kernel.org/all/20200416213229.19174-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
@rppt @mcgrof
execmem: don't remove ROX cache from the direct map
20d4655 
The memory allocated for the ROX cache was removed from the direct map to
reduce amount of direct map updates, however this cannot be tolerated by
/proc/kcore that accesses module memory using vread_iter() and the latter
does vmalloc_to_page() and copy_page_to_iter_nofault().

Instead of removing ROX cache memory from the direct map and mapping it as
ROX in vmalloc space, simply call set_memory_rox() that will take care of
proper permissions on both vmalloc and in the direct map.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
@rppt @mcgrof
execmem: add API for temporal remapping as RW and restoring ROX after…
02de34d 
…wards

Using a writable copy for ROX memory is cumbersome and error prone.

Add API that allow temporarily remapping of ranges in the ROX cache as
writable  and then restoring their read-only-execute permissions.

This API will be later used in modules code and will allow removing nasty
games with writable copy in alternatives patching on x86.

The restoring of the ROX permissions relies on the ability of architecture
to reconstruct large pages in its set_memory_rox() method.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
@rppt @mcgrof
module: switch to execmem API for remapping as RW and restoring ROX
89386f1 
Instead of using writable copy for module text sections, temporarily remap
the memory allocated from execmem's ROX cache as writable and restore its
ROX permissions after the module is formed.

This will allow removing nasty games with writable copy in alternatives
patching on x86.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Petr Pavlu <petr.pavlu@suse.com>
@rppt @mcgrof
Revert "x86/module: prepare module loading for ROX allocations of text"
cadc003 
The module code does not create a writable copy of the executable memory
anymore so there is no need to handle it in module relocation and
alternatives patching.

This reverts commit 9bfc482.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
@rppt @mcgrof
module: drop unused module_writable_address()
7ab1510 
module_writable_address() is unused and can be removed.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
@rppt @mcgrof
x86: re-enable EXECMEM_ROX support
cd42e64 
after rework of execmem ROX caches

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
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modules-kpd-app bot commented Feb 17, 2025

Upstream branch: afa9286
series: https://patchwork.kernel.org/project/linux-modules/list/?series=928370
version: 3

@modules-kpd-app modules-kpd-app bot force-pushed the series/921069=>modules-next branch from c534b53 to cd42e64 Compare February 17, 2025 10:03
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modules-kpd-app bot commented Mar 18, 2025

At least one diff in series https://patchwork.kernel.org/project/linux-modules/list/?series=928370 irrelevant now. Closing PR.

@modules-kpd-app modules-kpd-app bot closed this Mar 18, 2025
@modules-kpd-app modules-kpd-app bot deleted the series/921069=>modules-next branch March 18, 2025 22:57
modules-kpd-app bot pushed a commit that referenced this pull request May 5, 2025
@davem330
bnxt_en: Fix out-of-bound memcpy() during ethtool -w
6b87bd9 
When retrieving the FW coredump using ethtool, it can sometimes cause
memory corruption:

BUG: KFENCE: memory corruption in __bnxt_get_coredump+0x3ef/0x670 [bnxt_en]
Corrupted memory at 0x000000008f0f30e8 [ ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ] (in kfence-#45):
__bnxt_get_coredump+0x3ef/0x670 [bnxt_en]
ethtool_get_dump_data+0xdc/0x1a0
__dev_ethtool+0xa1e/0x1af0
dev_ethtool+0xa8/0x170
dev_ioctl+0x1b5/0x580
sock_do_ioctl+0xab/0xf0
sock_ioctl+0x1ce/0x2e0
__x64_sys_ioctl+0x87/0xc0
do_syscall_64+0x5c/0xf0
entry_SYSCALL_64_after_hwframe+0x78/0x80

...

This happens when copying the coredump segment list in
bnxt_hwrm_dbg_dma_data() with the HWRM_DBG_COREDUMP_LIST FW command.
The info->dest_buf buffer is allocated based on the number of coredump
segments returned by the FW.  The segment list is then DMA'ed by
the FW and the length of the DMA is returned by FW.  The driver then
copies this DMA'ed segment list to info->dest_buf.

In some cases, this DMA length may exceed the info->dest_buf length
and cause the above BUG condition.  Fix it by capping the copy
length to not exceed the length of info->dest_buf.  The extra
DMA data contains no useful information.

This code path is shared for the HWRM_DBG_COREDUMP_LIST and the
HWRM_DBG_COREDUMP_RETRIEVE FW commands.  The buffering is different
for these 2 FW commands.  To simplify the logic, we need to move
the line to adjust the buffer length for HWRM_DBG_COREDUMP_RETRIEVE
up, so that the new check to cap the copy length will work for both
commands.

Fixes: c74751f ("bnxt_en: Return error if FW returns more data than dump length")
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Shruti Parab <shruti.parab@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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@Joelgranados @toblux @mcgrof @rppt @kiryl