ACKs with no ABI symbol lists like mainline,
don't let any unsigned modules load as every
access is being treated as violation as
NO_OF_UNPROTECTED_SYMBOLS will be 0 in this case.
Check NO_OF_UNPROTECTED_SYMBOLS and if it's 0,
allow every symbol access by unsigned modules;
so we can keep the feature enable and also not
break any devices. It should never be 0 with
kernel branches where KMI_SYMBOL_LISTS have been
enabled.
Bug: 257458145
Bug: 232430739
Test: TH
Fixes: e9669eeb2f ("ANDROID: GKI: Add module load time symbol protection")
Change-Id: Iab65e1425473e32baaad0d6c7f0d3eb007ae864f
Signed-off-by: Ramji Jiyani <ramjiyani@google.com>
Add vendor hook for module init, so we can get memory type and
use it to do memory type check for architecture
dependent page table setting.
Bug: 248994334
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Change-Id: I1224945fd1f7950d46d6ea93c14dfd784658653c
Add CONFIG_MODULE_SIG_PROTECT to enable lookup for the unprotected
symbols from the build time generated list of symbols.
Module loading behavior will change as follows:
- Allows Android GKI Modules signed using MODULE_SIG_ALL during build.
- Allows other modules to load if they don't violate the access to
Android GKI protected symbols. Loading will fail and return
-EACCES (Permission denied) if these modules access the symbol which
is not allowlisted via symbol list or exported by a GKI module.
Bug: 232430739
Test: TH
Signed-off-by: Ramji Jiyani <ramjiyani@google.com>
Change-Id: I751b1951241b45712c20ac0e3878abd2152dd002
This reverts commit f5794dc184.
Reason for revert: Upstream mainline module code has been refactored;
and gki-modules implementation has changed, too. So, reverting all
old stuff and adding the new with rebase as single patch via
aosp/2260477.
Signed-off-by: Ramji Jiyani <ramjiyani@google.com>
Change-Id: I095a6bb8644a81703c3fbb273845a8d0a2c6e912
This ensures that no module record/or entry is added to the
unloaded_tainted_modules list if it does not carry a taint.
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Fixes: 99bd995655 ("module: Introduce module unload taint tracking")
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull module updates from Luis Chamberlain:
- minor enhancement for sysfs compression string (David Disseldorp)
- debugfs interface to view unloaded tainted modules (Aaron Tomlin)
* tag 'modules-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
module/decompress: generate sysfs string at compile time
module: Add debugfs interface to view unloaded tainted modules
Pull driver core updates from Greg KH:
"Here is the big set of driver core and debug printk changes for
6.1-rc1. Included in here is:
- dynamic debug updates for the core and the drm subsystem. The drm
changes have all been acked by the relevant maintainers
- kernfs fixes for syzbot reported problems
- kernfs refactors and updates for cgroup requirements
- magic number cleanups and removals from the kernel tree (they were
not being used and they really did not actually do anything)
- other tiny cleanups
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (74 commits)
docs: filesystems: sysfs: Make text and code for ->show() consistent
Documentation: NBD_REQUEST_MAGIC isn't a magic number
a.out: restore CMAGIC
device property: Add const qualifier to device_get_match_data() parameter
drm_print: add _ddebug descriptor to drm_*dbg prototypes
drm_print: prefer bare printk KERN_DEBUG on generic fn
drm_print: optimize drm_debug_enabled for jump-label
drm-print: add drm_dbg_driver to improve namespace symmetry
drm-print.h: include dyndbg header
drm_print: wrap drm_*_dbg in dyndbg descriptor factory macro
drm_print: interpose drm_*dbg with forwarding macros
drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.
drm_print: condense enum drm_debug_category
debugfs: use DEFINE_SHOW_ATTRIBUTE to define debugfs_regset32_fops
driver core: use IS_ERR_OR_NULL() helper in device_create_groups_vargs()
Documentation: ENI155_MAGIC isn't a magic number
Documentation: NBD_REPLY_MAGIC isn't a magic number
nbd: remove define-only NBD_MAGIC, previously magic number
Documentation: FW_HEADER_MAGIC isn't a magic number
Documentation: EEPROM_MAGIC_VALUE isn't a magic number
...
This patch provides debug/modules/unloaded_tainted file to see a
record of unloaded tainted modules.
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Add __dyndbg_classes section, using __dyndbg as a model. Use it:
vmlinux.lds.h:
KEEP the new section, which also silences orphan section warning on
loadable modules. Add (__start_/__stop_)__dyndbg_classes linker
symbols for the c externs (below).
kernel/module/main.c:
- fill new fields in find_module_sections(), using section_objs()
- extend callchain prototypes
to pass classes, length
load_module(): pass new info to dynamic_debug_setup()
dynamic_debug_setup(): new params, pass through to ddebug_add_module()
dynamic_debug.c:
- add externs to the linker symbols.
ddebug_add_module():
- It currently builds a debug_table, and *will* find and attach classes.
dynamic_debug_init():
- add class fields to the _ddebug_info cursor var: di.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20220904214134.408619-16-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This new struct composes the linker provided (vector,len) section,
and provides a place to add other __dyndbg[] state-data later:
descs - the vector of descriptors in __dyndbg section.
num_descs - length of the data/section.
Use it, in several different ways, as follows:
In lib/dynamic_debug.c:
ddebug_add_module(): Alter params-list, replacing 2 args (array,index)
with a struct _ddebug_info * containing them both, with room for
expansion. This helps future-proof the function prototype against the
looming addition of class-map info into the dyndbg-state, by providing
a place to add more member fields later.
NB: later add static struct _ddebug_info builtins_state declaration,
not needed yet.
ddebug_add_module() is called in 2 contexts:
In dynamic_debug_init(), declare, init a struct _ddebug_info di
auto-var to use as a cursor. Then iterate over the prdbg blocks of
the builtin modules, and update the di cursor before calling
_add_module for each.
Its called from kernel/module/main.c:load_info() for each loaded
module:
In internal.h, alter struct load_info, replacing the dyndbg array,len
fields with an embedded _ddebug_info containing them both; and
populate its members in find_module_sections().
The 2 calling contexts differ in that _init deals with contiguous
subranges of __dyndbgs[] section, packed together, while loadable
modules are added one at a time.
So rename ddebug_add_module() into outer/__inner fns, call __inner
from _init, and provide the offset into the builtin __dyndbgs[] where
the module's prdbgs reside. The cursor provides start, len of the
subrange for each. The offset will be used later to pack the results
of builtin __dyndbg_sites[] de-duplication, and is 0 and unneeded for
loadable modules,
Note:
kernel/module/main.c includes <dynamic_debug.h> for struct
_ddeubg_info. This might be prone to include loops, since its also
included by printk.h. Nothing has broken in robot-land on this.
cc: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20220904214134.408619-12-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Steps on the way to 6.0-rc1
Resolves merge conflicts with:
init/Kconfig
kernel/module/Kconfig
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I92b7f12c0ba853ee8bfc81d072fb6eced54dbfa9
The new KUnit module handling has KUnit test suites listed in a
.kunit_test_suites section of each module. This should be loaded when
the module is, but at the moment this only happens if KUnit is built-in.
Also load this when KUnit is enabled as a module: it'll not be usable
unless KUnit is loaded, but such modules are likely to depend on KUnit
anyway, so it's unlikely to ever be loaded needlessly.
Fixes: 3d6e446238 ("kunit: unify module and builtin suite definitions")
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Pull module updates from Luis Chamberlain:
"For the 6.0 merge window the modules code shifts to cleanup and minor
fixes effort. This becomes much easier to do and review now due to the
code split to its own directory from effort on the last kernel
release. I expect to see more of this with time and as we expand on
test coverage in the future. The cleanups and fixes come from usual
suspects such as Christophe Leroy and Aaron Tomlin but there are also
some other contributors.
One particular minor fix worth mentioning is from Helge Deller, where
he spotted a *forever* incorrect natural alignment on both ELF section
header tables:
* .altinstructions
* __bug_table sections
A lot of back and forth went on in trying to determine the ill effects
of this misalignment being present for years and it has been
determined there should be no real ill effects unless you have a buggy
exception handler. Helge actually hit one of these buggy exception
handlers on parisc which is how he ended up spotting this issue. When
implemented correctly these paths with incorrect misalignment would
just mean a performance penalty, but given that we are dealing with
alternatives on modules and with the __bug_table (where info regardign
BUG()/WARN() file/line information associated with it is stored) this
really shouldn't be a big deal.
The only other change with mentioning is the kmap() with
kmap_local_page() and my only concern with that was on what is done
after preemption, but the virtual addresses are restored after
preemption. This is only used on module decompression.
This all has sit on linux-next for a while except the kmap stuff which
has been there for 3 weeks"
* tag 'modules-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
module: Replace kmap() with kmap_local_page()
module: Show the last unloaded module's taint flag(s)
module: Use strscpy() for last_unloaded_module
module: Modify module_flags() to accept show_state argument
module: Move module's Kconfig items in kernel/module/
MAINTAINERS: Update file list for module maintainers
module: Use vzalloc() instead of vmalloc()/memset(0)
modules: Ensure natural alignment for .altinstructions and __bug_table sections
module: Increase readability of module_kallsyms_lookup_name()
module: Fix ERRORs reported by checkpatch.pl
module: Add support for default value for module async_probe
Pull KUnit updates from Shuah Khan:
"This consists of several fixes and an important feature to discourage
running KUnit tests on production systems. Running tests on a
production system could leave the system in a bad state.
Summary:
- Add a new taint type, TAINT_TEST to signal that a test has been
run.
This should discourage people from running these tests on
production systems, and to make it easier to tell if tests have
been run accidentally (by loading the wrong configuration, etc)
- Several documentation and tool enhancements and fixes"
* tag 'linux-kselftest-kunit-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (29 commits)
Documentation: KUnit: Fix example with compilation error
Documentation: kunit: Add CLI args for kunit_tool
kcsan: test: Add a .kunitconfig to run KCSAN tests
kunit: executor: Fix a memory leak on failure in kunit_filter_tests
clk: explicitly disable CONFIG_UML_PCI_OVER_VIRTIO in .kunitconfig
mmc: sdhci-of-aspeed: test: Use kunit_test_suite() macro
nitro_enclaves: test: Use kunit_test_suite() macro
thunderbolt: test: Use kunit_test_suite() macro
kunit: flatten kunit_suite*** to kunit_suite** in .kunit_test_suites
kunit: unify module and builtin suite definitions
selftest: Taint kernel when test module loaded
module: panic: Taint the kernel when selftest modules load
Documentation: kunit: fix example run_kunit func to allow spaces in args
Documentation: kunit: Cleanup run_wrapper, fix x-ref
kunit: test.h: fix a kernel-doc markup
kunit: tool: Enable virtio/PCI by default on UML
kunit: tool: make --kunitconfig repeatable, blindly concat
kunit: add coverage_uml.config to enable GCOV on UML
kunit: tool: refactor internal kconfig handling, allow overriding
kunit: tool: introduce --qemu_args
...
kmap() is being deprecated in favor of kmap_local_page().
Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap’s pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.
With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts).
Tasks can be preempted and, when scheduled to run again, the kernel
virtual addresses are restored and still valid.
kmap_local_page() is faster than kmap() in kernels with HIGHMEM enabled.
Since the use of kmap_local_page() in module_gzip_decompress() and in
module_xz_decompress() is safe (i.e., it does not break the strict rules
of use), it should be preferred over kmap().
Therefore, replace kmap() with kmap_local_page().
Tested on a QEMU/KVM x86_32 VM with 4GB RAM, booting kernels with
HIGHMEM64GB enabled. Modules compressed with XZ or GZIP decompress
properly.
Cc: Matthew Wilcox <willy@infradead.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
For diagnostic purposes, this patch, in addition to keeping a record/or
track of the last known unloaded module, we now will include the
module's taint flag(s) too e.g: " [last unloaded: fpga_mgr_mod(OE)]"
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
No functional change.
With this patch a given module's state information (i.e. 'mod->state')
can be omitted from the specified buffer. Please note that this is in
preparation to include the last unloaded module's taint flag(s),
if available.
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
In init/Kconfig, the part dedicated to modules is quite large.
Move it into a dedicated Kconfig in kernel/module/
MODULES_TREE_LOOKUP was outside of the 'if MODULES', but as it is
only used when MODULES are set, move it in with everything else to
avoid confusion.
MODULE_SIG_FORMAT is left in init/Kconfig because this configuration
item is not used in kernel/modules/ but in kernel/ and can be
selected independently from CONFIG_MODULES. It is for instance
selected from security/integrity/ima/Kconfig.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Currently, KUnit runs built-in tests and tests loaded from modules
differently. For built-in tests, the kunit_test_suite{,s}() macro adds a
list of suites in the .kunit_test_suites linker section. However, for
kernel modules, a module_init() function is used to run the test suites.
This causes problems if tests are included in a module which already
defines module_init/exit_module functions, as they'll conflict with the
kunit-provided ones.
This change removes the kunit-defined module inits, and instead parses
the kunit tests from their own section in the module. After module init,
we call __kunit_test_suites_init() on the contents of that section,
which prepares and runs the suite.
This essentially unifies the module- and non-module kunit init formats.
Tested-by: Maíra Canal <maira.canal@usp.br>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Taint the kernel with TAINT_TEST whenever a test module loads, by adding
a new "TEST" module property, and setting it for all modules in the
tools/testing directory. This property can also be set manually, for
tests which live outside the tools/testing directory with:
MODULE_INFO(test, "Y");
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
module_kallsyms_lookup_name() has several exit conditions but
can't return immediately due to preempt_disable().
Refactor module_kallsyms_lookup_name() to allow returning from
anywhere, and reduce depth.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Checkpatch reports following errors:
ERROR: do not use assignment in if condition
+ if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) {
ERROR: do not use assignment in if condition
+ if ((mod = find_module_all(name, colon - name, false)) != NULL)
ERROR: do not use assignment in if condition
+ if ((ret = find_kallsyms_symbol_value(mod, name)) != 0)
ERROR: do not initialise globals to 0
+int modules_disabled = 0;
Fix them.
The following one has to remain, because the condition has to be evaluated
multiple times by the macro wait_event_interruptible_timeout().
ERROR: do not use assignment in if condition
+ if (wait_event_interruptible_timeout(module_wq,
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Add a module.async_probe kernel command line option that allows enabling
async probing for all modules. When this command line option is used,
there might still be some modules for which we want to explicitly force
synchronous probing, so extend <modulename>.async_probe to take an
optional bool input so that async probing can be disabled for a specific
module.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
The commit 08126db5ff ("module: kallsyms: Fix suspicious rcu usage")
under PREEMPT_RT=y, disabling preemption introduced an unbounded
latency since the loop is not fixed. This change caused a regression
since previously preemption was not disabled and we would dereference
RCU-protected pointers explicitly. That being said, these pointers
cannot change.
Before kallsyms-specific data is prepared/or set-up, we ensure that
the unformed module is known to be unique i.e. does not already exist
(see load_module()). Therefore, we can fix this by using the common and
more appropriate RCU flavour as this section of code can be safely
preempted.
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: 08126db5ff ("module: kallsyms: Fix suspicious rcu usage")
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
When CONFIG_MODULE_UNLOAD is not selected, 'exit' is
set but never used.
It is not possible to replace the #ifdef CONFIG_MODULE_UNLOAD by
IS_ENABLED(CONFIG_MODULE_UNLOAD) because mod->exit doesn't exist
when CONFIG_MODULE_UNLOAD is not selected.
And because of the rcu_read_lock_sched() section it is not easy
to regroup everything in a single #ifdef. Let's regroup partially
and add missing #ifdef to completely opt out the use of
'exit' when CONFIG_MODULE_UNLOAD is not selected.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
cppcheck reports the following warnings:
kernel/module/main.c:1455:26: warning: Redundant assignment of 'mod->core_layout.size' to itself. [selfAssignment]
mod->core_layout.size = strict_align(mod->core_layout.size);
^
kernel/module/main.c:1489:26: warning: Redundant assignment of 'mod->init_layout.size' to itself. [selfAssignment]
mod->init_layout.size = strict_align(mod->init_layout.size);
^
kernel/module/main.c:1493:26: warning: Redundant assignment of 'mod->init_layout.size' to itself. [selfAssignment]
mod->init_layout.size = strict_align(mod->init_layout.size);
^
kernel/module/main.c:1504:26: warning: Redundant assignment of 'mod->init_layout.size' to itself. [selfAssignment]
mod->init_layout.size = strict_align(mod->init_layout.size);
^
kernel/module/main.c:1459:26: warning: Redundant assignment of 'mod->data_layout.size' to itself. [selfAssignment]
mod->data_layout.size = strict_align(mod->data_layout.size);
^
kernel/module/main.c:1463:26: warning: Redundant assignment of 'mod->data_layout.size' to itself. [selfAssignment]
mod->data_layout.size = strict_align(mod->data_layout.size);
^
kernel/module/main.c:1467:26: warning: Redundant assignment of 'mod->data_layout.size' to itself. [selfAssignment]
mod->data_layout.size = strict_align(mod->data_layout.size);
^
This is due to strict_align() being a no-op when
CONFIG_STRICT_MODULE_RWX is not selected.
Transform strict_align() macro into an inline function. It will
allow type checking and avoid the selfAssignment warning.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
The commit 91fb02f315 ("module: Move kallsyms support into a separate
file") changed from using strlcpy() to using strscpy() which created a
buffer overflow. That happened because:
1) an incorrect value was passed as the buffer length
2) strscpy() (unlike strlcpy()) may copy beyond the length of the
input string when copying word-by-word.
The assumption was that because it was already known that the strings
being copied would fit in the space available, it was not necessary
to correctly set the buffer length. strscpy() breaks that assumption
because although it will not touch bytes beyond the given buffer length
it may write bytes beyond the input string length when writing
word-by-word.
The result of the buffer overflow is to corrupt the symbol type
information that follows. e.g.
$ sudo cat -v /proc/kallsyms | grep '\^' | head
ffffffffc0615000 ^@ rfcomm_session_get [rfcomm]
ffffffffc061c060 ^@ session_list [rfcomm]
ffffffffc06150d0 ^@ rfcomm_send_frame [rfcomm]
ffffffffc0615130 ^@ rfcomm_make_uih [rfcomm]
ffffffffc07ed58d ^@ bnep_exit [bnep]
ffffffffc07ec000 ^@ bnep_rx_control [bnep]
ffffffffc07ec1a0 ^@ bnep_session [bnep]
ffffffffc07e7000 ^@ input_leds_event [input_leds]
ffffffffc07e9000 ^@ input_leds_handler [input_leds]
ffffffffc07e7010 ^@ input_leds_disconnect [input_leds]
Notably, the null bytes (represented above by ^@) can confuse tools.
Fix by correcting the buffer length.
Fixes: 91fb02f315 ("module: Move kallsyms support into a separate file")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
This reverts commit 090a1da697.
It brings it back now that we have merged around the problem area.
Bug: 200082547
Bug: 214445388
Cc: Ramji Jiyani <ramjiyani@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Iaa69221f341bf2face454ec0452efff2cbba9042
Pull modules updates from Luis Chamberlain:
- It was time to tidy up kernel/module.c and one way of starting with
that effort was to split it up into files. At my request Aaron Tomlin
spearheaded that effort with the goal to not introduce any functional
at all during that endeavour. The penalty for the split is +1322
bytes total, +112 bytes in data, +1210 bytes in text while bss is
unchanged. One of the benefits of this other than helping make the
code easier to read and review is summoning more help on review for
changes with livepatching so kernel/module/livepatch.c is now pegged
as maintained by the live patching folks.
The before and after with just the move on a defconfig on x86-64:
$ size kernel/module.o
text data bss dec hex filename
38434 4540 104 43078 a846 kernel/module.o
$ size -t kernel/module/*.o
text data bss dec hex filename
4785 120 0 4905 1329 kernel/module/kallsyms.o
28577 4416 104 33097 8149 kernel/module/main.o
1158 8 0 1166 48e kernel/module/procfs.o
902 108 0 1010 3f2 kernel/module/strict_rwx.o
3390 0 0 3390 d3e kernel/module/sysfs.o
832 0 0 832 340 kernel/module/tree_lookup.o
39644 4652 104 44400 ad70 (TOTALS)
- Aaron added module unload taint tracking (MODULE_UNLOAD_TAINT_TRACKING),
to enable tracking unloaded modules which did taint the kernel.
- Christophe Leroy added CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
which lets architectures to request having modules data in vmalloc
area instead of module area. There are three reasons why an
architecture might want this:
a) On some architectures (like book3s/32) it is not possible to
protect against execution on a page basis. The exec stuff can be
mapped by different arch segment sizes (on book3s/32 that is 256M
segments). By default the module area is in an Exec segment while
vmalloc area is in a NoExec segment. Using vmalloc lets you muck
with module data as NoExec on those architectures whereas before
you could not.
b) By pushing more module data to vmalloc you also increase the
probability of module text to remain within a closer distance
from kernel core text and this reduces trampolines, this has been
reported on arm first and powerpc folks are following that lead.
c) Free'ing module_alloc() (Exec by default) area leaves this
exposed as Exec by default, some architectures have some security
enhancements to set this as NoExec on free, and splitting module
data with text let's future generic special allocators be added
to the kernel without having developers try to grok the tribal
knowledge per arch. Work like Rick Edgecombe's permission vmalloc
interface [0] becomes easier to address over time.
[0] https://lore.kernel.org/lkml/20201120202426.18009-1-rick.p.edgecombe@intel.com/#r
- Masahiro Yamada's symbol search enhancements
* tag 'modules-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (33 commits)
module: merge check_exported_symbol() into find_exported_symbol_in_section()
module: do not binary-search in __ksymtab_gpl if fsa->gplok is false
module: do not pass opaque pointer for symbol search
module: show disallowed symbol name for inherit_taint()
module: fix [e_shstrndx].sh_size=0 OOB access
module: Introduce module unload taint tracking
module: Move module_assert_mutex_or_preempt() to internal.h
module: Make module_flags_taint() accept a module's taints bitmap and usable outside core code
module.h: simplify MODULE_IMPORT_NS
powerpc: Select ARCH_WANTS_MODULES_DATA_IN_VMALLOC on book3s/32 and 8xx
module: Remove module_addr_min and module_addr_max
module: Add CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
module: Introduce data_layout
module: Prepare for handling several RB trees
module: Always have struct mod_tree_root
module: Rename debug_align() as strict_align()
module: Rework layout alignment to avoid BUG_ON()s
module: Move module_enable_x() and frob_text() in strict_rwx.c
module: Make module_enable_x() independent of CONFIG_ARCH_HAS_STRICT_MODULE_RWX
module: Move version support into a separate file
...
Now check_exported_symbol() always succeeds.
Merge it into find_exported_symbol_in_search() to make the code concise.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Currently, !fsa->gplok && syms->license == GPL_ONLY) is checked after
bsearch() succeeds.
It is meaningless to do the binary search in the GPL symbol table when
fsa->gplok is false because we know find_exported_symbol_in_section()
will fail anyway.
This check should be done before bsearch().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
There is no need to use an opaque pointer for check_exported_symbol()
or find_exported_symbol_in_section.
Pass (struct find_symbol_arg *) explicitly.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
The error log for inherit_taint() doesn't really help to find the
symbol which violates GPL rules.
For example,
if a module has 300 symbol and includes 50 disallowed symbols,
the log only shows the content below and we have no idea what symbol is.
AAA: module using GPL-only symbols uses symbols from proprietary module BBB.
It's hard for user who doesn't really know how the symbol was parsing.
This patch add symbol name to tell the offending symbols explicitly.
AAA: module using GPL-only symbols uses symbols SSS from proprietary module BBB.
Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Currently, only the initial module that tainted the kernel is
recorded e.g. when an out-of-tree module is loaded.
The purpose of this patch is to allow the kernel to maintain a record of
each unloaded module that taints the kernel. So, in addition to
displaying a list of linked modules (see print_modules()) e.g. in the
event of a detected bad page, unloaded modules that carried a taint/or
taints are displayed too. A tainted module unload count is maintained.
The number of tracked modules is not fixed. This feature is disabled by
default.
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
No functional change.
This patch migrates module_assert_mutex_or_preempt() to internal.h.
So, the aforementiond function can be used outside of main/or core
module code yet will remain restricted for internal use only.
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
