Historically, various parameter-handling code kept pointers into
module::args, most notably the charp support. However, in 2009,
commit e180a6b775 ("param: fix charp parameters set via sysfs") changed
charp parameters to kstrdup() the input string as well. As a result,
module::args now mostly wastes memory.
The last users that still pointed into module::args have now been cleaned
up, so remove this data.
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
module_total_size() returns unsigned int but uses a signed int
accumulator. While the result is numerically correct, the type
mismatch is misleading.
Change the accumulator to unsigned int to match the return type.
Signed-off-by: Naveen Kumar Chaudhary <naveen.osdev@gmail.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
[ppavlu: correct the commit title]
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Both try_add_failed_module() and kmod_dup_request_exists_wait() use
memcpy() with strlen() to copy module names into fixed-size
char[MODULE_NAME_LEN] buffers. Neither performs a bounds check on the
copy. Current callers always pass names originating from
mod->name (itself char[MODULE_NAME_LEN]), so this is not exploitable
today. However both functions accept a plain const char * with no
documented length contract, making them latent buffer overflows if a
future caller passes a longer string.
Replace memcpy() with strscpy() in both sites, which bounds the copy
to MODULE_NAME_LEN and always NUL-terminates.
Signed-off-by: Naveen Kumar Chaudhary <naveen.osdev@gmail.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
The symbol lookup code assumes the queried address resides in either
MOD_TEXT or MOD_INIT_TEXT. This breaks for addresses in other module
memory regions (e.g. rodata or data), resulting in incorrect upper
bounds and wrong symbol size.
Select the module memory region the address belongs to instead of
hardcoding text sections. Also initialize the lower bound to the start
of that region, as searching from address 0 is unnecessary.
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
module_extend_max_pages() calls kvrealloc() internally and returns
-ENOMEM on allocation failure. The return value is never checked.
If the initial allocation fails, info->pages remains NULL and
info->max_pages remains 0. Subsequent calls to module_get_next_page()
will attempt to dynamically grow the array by calling
module_extend_max_pages(info, 0) since info->used_pages is 0. This
results in kvrealloc(NULL, 0) returning ZERO_SIZE_PTR, which is treated
as a success, leading to a dereference of ZERO_SIZE_PTR and a kernel
oops.
Fix: add the missing error check after module_extend_max_pages() and
return immediately on failure. This matches the pattern used by every
other kvrealloc() caller in the module loading path.
Fixes: b1ae6dc41e ("module: add in-kernel support for decompressing")
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Andrii Kuchmenko <capyenglishlite@gmail.com>
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
[Sami: Corrected the analysis in the commit message.]
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
It should now be rare to trigger this warning - it doesn't need to be so
verbose. Make it follow the usual style in the module loading code.
For the same reason, drop the dump_stack().
Suggested-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Lucas De Marchi <demarchi@kernel.org>
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
The *_gpl section are not being used populated by modpost anymore. Hence
the module loader doesn't need to find and process these sections in
modules.
This patch also simplifies symbol finding logic in module loader since
*_gpl sections don't have to be searched anymore.
Signed-off-by: Siddharth Nayyar <sidnayyar@google.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Read kflagstab section for vmlinux and modules to determine whether
kernel symbols are GPL only.
This patch eliminates the need for fragmenting the ksymtab for infering
the value of GPL-only symbol flag, henceforth stop populating *_gpl
versions of the ksymtab and kcrctab in modpost.
Signed-off-by: Siddharth Nayyar <sidnayyar@google.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
The purpose of the constant it is not entirely clear from its name.
As this constant is going to be exposed in a UAPI header, give it a more
specific name for clarity. As all its users call it 'marker', use that
wording in the constant itself.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Add /sys/module/*/import_ns to expose imported namespaces for
currently loaded modules. The file contains one namespace per line and
only exists for modules that import at least one namespace.
Previously, the only way for userspace to inspect the symbol
namespaces a module imports is to locate the .ko on disk and invoke
modinfo(8) to decompress/parse the metadata. The kernel validated
namespaces at load time, but it was otherwise discarded.
Exposing this data via sysfs provides a runtime mechanism to verify
which namespaces are being used by modules. For example, this allows
userspace to audit driver API access in Android GKI, which uses symbol
namespaces to restrict vendor drivers from using specific kernel
interfaces (e.g., direct filesystem access).
Signed-off-by: Nicholas Sielicki <linux@opensource.nslick.com>
[Sami: Updated the commit message to explain motivation.]
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
When setting a charp module parameter, the param_set_charp() function
allocates memory to store a copy of the input value. Later, when the module
is potentially unloaded, the destroy_params() function is called to free
this allocated memory.
However, destroy_params() is available only when CONFIG_SYSFS=y, otherwise
only a dummy variant is present. In the unlikely case that the kernel is
configured with CONFIG_MODULES=y and CONFIG_SYSFS=n, this results in
a memory leak of charp values when a module is unloaded.
Fix this issue by making destroy_params() always available when
CONFIG_MODULES=y. Rename the function to module_destroy_params() to clarify
that it is intended for use by the module loader.
Fixes: e180a6b775 ("param: fix charp parameters set via sysfs")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
The module loader doesn't check for bounds of the ELF section index in
simplify_symbols():
for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
const char *name = info->strtab + sym[i].st_name;
switch (sym[i].st_shndx) {
case SHN_COMMON:
[...]
default:
/* Divert to percpu allocation if a percpu var. */
if (sym[i].st_shndx == info->index.pcpu)
secbase = (unsigned long)mod_percpu(mod);
else
/** HERE --> **/ secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
sym[i].st_value += secbase;
break;
}
}
A symbol with an out-of-bounds st_shndx value, for example 0xffff
(known as SHN_XINDEX or SHN_HIRESERVE), may cause a kernel panic:
BUG: unable to handle page fault for address: ...
RIP: 0010:simplify_symbols+0x2b2/0x480
...
Kernel panic - not syncing: Fatal exception
This can happen when module ELF is legitimately using SHN_XINDEX or
when it is corrupted.
Add a bounds check in simplify_symbols() to validate that st_shndx is
within the valid range before using it.
This issue was discovered due to a bug in llvm-objcopy, see relevant
discussion for details [1].
[1] https://lore.kernel.org/linux-modules/20251224005752.201911-1-ihor.solodrai@linux.dev/
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
The module Kconfig file contains a set of options related to "Module
versioning support" (depends on MODVERSIONS) and "Module signature
verification" (depends on MODULE_SIG). The Kconfig tool automatically
creates submenus when an entry for a symbol is followed by consecutive
items that all depend on the symbol. However, this functionality doesn't
work for the mentioned module options. The MODVERSIONS options are
interleaved with ASM_MODVERSIONS, which has no 'depends on MODVERSIONS' but
instead uses 'default HAVE_ASM_MODVERSIONS && MODVERSIONS'. Similarly, the
MODULE_SIG options are interleaved by a comment warning not to forget
signing modules with scripts/sign-file, which uses the condition 'depends
on MODULE_SIG_FORCE && !MODULE_SIG_ALL'.
The result is that the options are confusingly shown when using
a menuconfig tool, as follows:
[*] Module versioning support
Module versioning implementation (genksyms (from source code)) --->
[ ] Extended Module Versioning Support
[*] Basic Module Versioning Support
[*] Source checksum for all modules
[*] Module signature verification
[ ] Require modules to be validly signed
[ ] Automatically sign all modules
Hash algorithm to sign modules (SHA-256) --->
Fix the issue by using if/endif to group related options together in
kernel/module/Kconfig, similarly to how the MODULE_DEBUG options are
already grouped. Note that the signing-related options depend on
'MODULE_SIG || IMA_APPRAISE_MODSIG', with the exception of
MODULE_SIG_FORCE, which is valid only for MODULE_SIG and is therefore kept
separately. For consistency, do the same for the MODULE_COMPRESS entries.
The options are then properly placed into submenus, as follows:
[*] Module versioning support
Module versioning implementation (genksyms (from source code)) --->
[ ] Extended Module Versioning Support
[*] Basic Module Versioning Support
[*] Source checksum for all modules
[*] Module signature verification
[ ] Require modules to be validly signed
[ ] Automatically sign all modules
Hash algorithm to sign modules (SHA-256) --->
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
In the error path of load_module(), under the free_module label, the
code calls lockdep_free_key_range() to release lock classes associated
with the MOD_DATA, MOD_RODATA and MOD_RO_AFTER_INIT module regions, and
subsequently invokes module_deallocate().
Since commit ac3b432839 ("module: replace module_layout with
module_memory"), the module_deallocate() function calls free_mod_mem(),
which releases the lock classes as well and considers all module
regions.
Attempting to free these classes twice is unnecessary. Remove the
redundant code in load_module().
Fixes: ac3b432839 ("module: replace module_layout with module_memory")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.
As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Pull non-MM updates from Andrew Morton:
- "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves
disk space by teaching ocfs2 to reclaim suballocator block group
space (Heming Zhao)
- "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the
ARRAY_END() macro and uses it in various places (Alejandro Colomar)
- "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes
the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the
page size (Pnina Feder)
- "kallsyms: Prevent invalid access when showing module buildid" cleans
up kallsyms code related to module buildid and fixes an invalid
access crash when printing backtraces (Petr Mladek)
- "Address page fault in ima_restore_measurement_list()" fixes a
kexec-related crash that can occur when booting the second-stage
kernel on x86 (Harshit Mogalapalli)
- "kho: ABI headers and Documentation updates" updates the kexec
handover ABI documentation (Mike Rapoport)
- "Align atomic storage" adds the __aligned attribute to atomic_t and
atomic64_t definitions to get natural alignment of both types on
csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain)
- "kho: clean up page initialization logic" simplifies the page
initialization logic in kho_restore_page() (Pratyush Yadav)
- "Unload linux/kernel.h" moves several things out of kernel.h and into
more appropriate places (Yury Norov)
- "don't abuse task_struct.group_leader" removes the usage of
->group_leader when it is "obviously unnecessary" (Oleg Nesterov)
- "list private v2 & luo flb" adds some infrastructure improvements to
the live update orchestrator (Pasha Tatashin)
* tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits)
watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency
procfs: fix missing RCU protection when reading real_parent in do_task_stat()
watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()
kcsan, compiler_types: avoid duplicate type issues in BPF Type Format
kho: fix doc for kho_restore_pages()
tests/liveupdate: add in-kernel liveupdate test
liveupdate: luo_flb: introduce File-Lifecycle-Bound global state
liveupdate: luo_file: Use private list
list: add kunit test for private list primitives
list: add primitives for private list manipulations
delayacct: fix uapi timespec64 definition
panic: add panic_force_cpu= parameter to redirect panic to a specific CPU
netclassid: use thread_group_leader(p) in update_classid_task()
RDMA/umem: don't abuse current->group_leader
drm/pan*: don't abuse current->group_leader
drm/amd: kill the outdated "Only the pthreads threading model is supported" checks
drm/amdgpu: don't abuse current->group_leader
android/binder: use same_thread_group(proc->tsk, current) in binder_mmap()
android/binder: don't abuse current->group_leader
kho: skip memoryless NUMA nodes when reserving scratch areas
...
Pull module updates from Sami Tolvanen:
"Module signing:
- Remove SHA-1 support for signing modules.
SHA-1 is no longer considered secure for signatures due to
vulnerabilities that can lead to hash collisions. None of the major
distributions use SHA-1 anymore, and the kernel has defaulted to
SHA-512 since v6.11.
Note that loading SHA-1 signed modules is still supported.
- Update scripts/sign-file to use only the OpenSSL CMS API for
signing.
As SHA-1 support is gone, we can drop the legacy PKCS#7 API which
was limited to SHA-1. This also cleans up support for legacy
OpenSSL versions.
Cleanups and fixes:
- Use system_dfl_wq instead of the per-cpu system_wq following the
ongoing workqueue API refactoring.
- Avoid open-coded kvrealloc() in module decompression logic by using
the standard helper.
- Improve section annotations by replacing the custom __modinit with
__init_or_module and removing several unused __INIT*_OR_MODULE
macros.
- Fix kernel-doc warnings in include/linux/moduleparam.h.
- Ensure set_module_sig_enforced is only declared when module signing
is enabled.
- Fix gendwarfksyms build failures on 32-bit hosts.
MAINTAINERS:
- Update the module subsystem entry to reflect the maintainer
rotation and update the git repository link"
* tag 'modules-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux:
modules: moduleparam.h: fix kernel-doc comments
module: Only declare set_module_sig_enforced when CONFIG_MODULE_SIG=y
module/decompress: Avoid open-coded kvrealloc()
gendwarfksyms: Fix build on 32-bit hosts
sign-file: Use only the OpenSSL CMS API for signing
module: Remove SHA-1 support for module signing
module: replace use of system_wq with system_dfl_wq
params: Replace __modinit with __init_or_module
module: Remove unused __INIT*_OR_MODULE macros
MAINTAINERS: Update module subsystem maintainers and repository
Add a GPL-2.0 license identifier line for this file.
kmod.c was originally introduced in the kernel in February
of 1998 by Linus Torvalds - who was familiar with kernel
licensing at the time this was introduced.
Signed-off-by: Tim Bird <tim.bird@sony.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SHA-1 is considered deprecated and insecure due to vulnerabilities that can
lead to hash collisions. Most distributions have already been using SHA-2
for module signing because of this. The default was also changed last year
from SHA-1 to SHA-512 in commit f3b93547b9 ("module: sign with sha512
instead of sha1 by default"). This was not reported to cause any issues.
Therefore, it now seems to be a good time to remove SHA-1 support for
module signing.
Commit 16ab7cb582 ("crypto: pkcs7 - remove sha1 support") previously
removed support for reading PKCS#7/CMS signed with SHA-1, along with the
ability to use SHA-1 for module signing. This change broke iwd and was
subsequently completely reverted in commit 203a6763ab ("Revert "crypto:
pkcs7 - remove sha1 support""). However, dropping only the support for
using SHA-1 for module signing is unrelated and can still be done
separately.
Note that this change only removes support for new modules to be SHA-1
signed, but already signed modules can still be loaded.
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Currently if a user enqueues a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.
This lack of consistency cannot be addressed without refactoring the API.
This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:
commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")
Switch to using system_dfl_wq, the new unbound workqueue, because the
users do not benefit from a per-cpu workqueue.
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
