Commit Graph

701 Commits

Author SHA1 Message Date
Greg Kroah-Hartman
2ded03fd7c Merge 5.15.25 into android13-5.15
Changes in 5.15.25
	drm/nouveau/pmu/gm200-: use alternate falcon reset sequence
	fs/proc: task_mmu.c: don't read mapcount for migration entry
	btrfs: zoned: cache reported zone during mount
	scsi: lpfc: Fix mailbox command failure during driver initialization
	HID:Add support for UGTABLET WP5540
	Revert "svm: Add warning message for AVIC IPI invalid target"
	parisc: Show error if wrong 32/64-bit compiler is being used
	serial: parisc: GSC: fix build when IOSAPIC is not set
	parisc: Drop __init from map_pages declaration
	parisc: Fix data TLB miss in sba_unmap_sg
	parisc: Fix sglist access in ccio-dma.c
	mmc: block: fix read single on recovery logic
	mm: don't try to NUMA-migrate COW pages that have other uses
	HID: amd_sfh: Add illuminance mask to limit ALS max value
	HID: i2c-hid: goodix: Fix a lockdep splat
	HID: amd_sfh: Increase sensor command timeout
	HID: amd_sfh: Correct the structure field name
	PCI: hv: Fix NUMA node assignment when kernel boots with custom NUMA topology
	parisc: Add ioread64_lo_hi() and iowrite64_lo_hi()
	btrfs: send: in case of IO error log it
	platform/x86: touchscreen_dmi: Add info for the RWC NANOTE P8 AY07J 2-in-1
	platform/x86: ISST: Fix possible circular locking dependency detected
	kunit: tool: Import missing importlib.abc
	selftests: rtc: Increase test timeout so that all tests run
	kselftest: signal all child processes
	net: ieee802154: at86rf230: Stop leaking skb's
	selftests/zram: Skip max_comp_streams interface on newer kernel
	selftests/zram01.sh: Fix compression ratio calculation
	selftests/zram: Adapt the situation that /dev/zram0 is being used
	selftests: openat2: Print also errno in failure messages
	selftests: openat2: Add missing dependency in Makefile
	selftests: openat2: Skip testcases that fail with EOPNOTSUPP
	selftests: skip mincore.check_file_mmap when fs lacks needed support
	ax25: improve the incomplete fix to avoid UAF and NPD bugs
	pinctrl: bcm63xx: fix unmet dependency on REGMAP for GPIO_REGMAP
	vfs: make freeze_super abort when sync_filesystem returns error
	quota: make dquot_quota_sync return errors from ->sync_fs
	scsi: pm80xx: Fix double completion for SATA devices
	kselftest: Fix vdso_test_abi return status
	scsi: core: Reallocate device's budget map on queue depth change
	scsi: pm8001: Fix use-after-free for aborted TMF sas_task
	scsi: pm8001: Fix use-after-free for aborted SSP/STP sas_task
	drm/amd: Warn users about potential s0ix problems
	nvme: fix a possible use-after-free in controller reset during load
	nvme-tcp: fix possible use-after-free in transport error_recovery work
	nvme-rdma: fix possible use-after-free in transport error_recovery work
	net: sparx5: do not refer to skb after passing it on
	drm/amd: add support to check whether the system is set to s3
	drm/amd: Only run s3 or s0ix if system is configured properly
	drm/amdgpu: fix logic inversion in check
	x86/Xen: streamline (and fix) PV CPU enumeration
	Revert "module, async: async_synchronize_full() on module init iff async is used"
	gcc-plugins/stackleak: Use noinstr in favor of notrace
	random: wake up /dev/random writers after zap
	KVM: x86/xen: Fix runstate updates to be atomic when preempting vCPU
	KVM: x86: nSVM/nVMX: set nested_run_pending on VM entry which is a result of RSM
	KVM: x86: SVM: don't passthrough SMAP/SMEP/PKE bits in !NPT && !gCR0.PG case
	KVM: x86: nSVM: fix potential NULL derefernce on nested migration
	KVM: x86: nSVM: mark vmcb01 as dirty when restoring SMM saved state
	iwlwifi: fix use-after-free
	drm/radeon: Fix backlight control on iMac 12,1
	drm/atomic: Don't pollute crtc_state->mode_blob with error pointers
	drm/amd/pm: correct the sequence of sending gpu reset msg
	drm/amdgpu: skipping SDMA hw_init and hw_fini for S0ix.
	drm/i915/opregion: check port number bounds for SWSCI display power state
	drm/i915: Fix dbuf slice config lookup
	drm/i915: Fix mbus join config lookup
	vsock: remove vsock from connected table when connect is interrupted by a signal
	drm/cma-helper: Set VM_DONTEXPAND for mmap
	drm/i915/gvt: Make DRM_I915_GVT depend on X86
	drm/i915/ttm: tweak priority hint selection
	iwlwifi: pcie: fix locking when "HW not ready"
	iwlwifi: pcie: gen2: fix locking when "HW not ready"
	iwlwifi: mvm: don't send SAR GEO command for 3160 devices
	selftests: netfilter: fix exit value for nft_concat_range
	netfilter: nft_synproxy: unregister hooks on init error path
	selftests: netfilter: disable rp_filter on router
	ipv4: fix data races in fib_alias_hw_flags_set
	ipv6: fix data-race in fib6_info_hw_flags_set / fib6_purge_rt
	ipv6: mcast: use rcu-safe version of ipv6_get_lladdr()
	ipv6: per-netns exclusive flowlabel checks
	Revert "net: ethernet: bgmac: Use devm_platform_ioremap_resource_byname"
	mac80211: mlme: check for null after calling kmemdup
	brcmfmac: firmware: Fix crash in brcm_alt_fw_path
	cfg80211: fix race in netlink owner interface destruction
	net: dsa: lan9303: fix reset on probe
	net: dsa: mv88e6xxx: flush switchdev FDB workqueue before removing VLAN
	net: dsa: lantiq_gswip: fix use after free in gswip_remove()
	net: dsa: lan9303: handle hwaccel VLAN tags
	net: dsa: lan9303: add VLAN IDs to master device
	net: ieee802154: ca8210: Fix lifs/sifs periods
	ping: fix the dif and sdif check in ping_lookup
	bonding: force carrier update when releasing slave
	drop_monitor: fix data-race in dropmon_net_event / trace_napi_poll_hit
	net_sched: add __rcu annotation to netdev->qdisc
	bonding: fix data-races around agg_select_timer
	libsubcmd: Fix use-after-free for realloc(..., 0)
	net/smc: Avoid overwriting the copies of clcsock callback functions
	net: phy: mediatek: remove PHY mode check on MT7531
	atl1c: fix tx timeout after link flap on Mikrotik 10/25G NIC
	tipc: fix wrong publisher node address in link publications
	dpaa2-switch: fix default return of dpaa2_switch_flower_parse_mirror_key
	dpaa2-eth: Initialize mutex used in one step timestamping path
	net: bridge: multicast: notify switchdev driver whenever MC processing gets disabled
	perf bpf: Defer freeing string after possible strlen() on it
	selftests/exec: Add non-regular to TEST_GEN_PROGS
	arm64: Correct wrong label in macro __init_el2_gicv3
	ALSA: usb-audio: revert to IMPLICIT_FB_FIXED_DEV for M-Audio FastTrack Ultra
	ALSA: hda/realtek: Add quirk for Legion Y9000X 2019
	ALSA: hda/realtek: Fix deadlock by COEF mutex
	ALSA: hda: Fix regression on forced probe mask option
	ALSA: hda: Fix missing codec probe on Shenker Dock 15
	ASoC: ops: Fix stereo change notifications in snd_soc_put_volsw()
	ASoC: ops: Fix stereo change notifications in snd_soc_put_volsw_range()
	ASoC: ops: Fix stereo change notifications in snd_soc_put_volsw_sx()
	ASoC: ops: Fix stereo change notifications in snd_soc_put_xr_sx()
	cifs: fix set of group SID via NTSD xattrs
	powerpc/603: Fix boot failure with DEBUG_PAGEALLOC and KFENCE
	powerpc/lib/sstep: fix 'ptesync' build error
	mtd: rawnand: gpmi: don't leak PM reference in error path
	smb3: fix snapshot mount option
	tipc: fix wrong notification node addresses
	scsi: ufs: Remove dead code
	scsi: ufs: Fix a deadlock in the error handler
	ASoC: tas2770: Insert post reset delay
	ASoC: qcom: Actually clear DMA interrupt register for HDMI
	block/wbt: fix negative inflight counter when remove scsi device
	NFS: Remove an incorrect revalidation in nfs4_update_changeattr_locked()
	NFS: LOOKUP_DIRECTORY is also ok with symlinks
	NFS: Do not report writeback errors in nfs_getattr()
	tty: n_tty: do not look ahead for EOL character past the end of the buffer
	block: fix surprise removal for drivers calling blk_set_queue_dying
	mtd: rawnand: qcom: Fix clock sequencing in qcom_nandc_probe()
	mtd: parsers: qcom: Fix kernel panic on skipped partition
	mtd: parsers: qcom: Fix missing free for pparts in cleanup
	mtd: phram: Prevent divide by zero bug in phram_setup()
	mtd: rawnand: brcmnand: Fixed incorrect sub-page ECC status
	HID: elo: fix memory leak in elo_probe
	mtd: rawnand: ingenic: Fix missing put_device in ingenic_ecc_get
	Drivers: hv: vmbus: Fix memory leak in vmbus_add_channel_kobj
	KVM: x86/pmu: Refactoring find_arch_event() to pmc_perf_hw_id()
	KVM: x86/pmu: Don't truncate the PerfEvtSeln MSR when creating a perf event
	KVM: x86/pmu: Use AMD64_RAW_EVENT_MASK for PERF_TYPE_RAW
	ARM: OMAP2+: hwmod: Add of_node_put() before break
	ARM: OMAP2+: adjust the location of put_device() call in omapdss_init_of
	phy: usb: Leave some clocks running during suspend
	staging: vc04_services: Fix RCU dereference check
	phy: phy-mtk-tphy: Fix duplicated argument in phy-mtk-tphy
	irqchip/sifive-plic: Add missing thead,c900-plic match string
	x86/bug: Merge annotate_reachable() into _BUG_FLAGS() asm
	netfilter: conntrack: don't refresh sctp entries in closed state
	ksmbd: fix same UniqueId for dot and dotdot entries
	ksmbd: don't align last entry offset in smb2 query directory
	arm64: dts: meson-gx: add ATF BL32 reserved-memory region
	arm64: dts: meson-g12: add ATF BL32 reserved-memory region
	arm64: dts: meson-g12: drop BL32 region from SEI510/SEI610
	pidfd: fix test failure due to stack overflow on some arches
	selftests: fixup build warnings in pidfd / clone3 tests
	mm: io_uring: allow oom-killer from io_uring_setup
	ACPI: PM: Revert "Only mark EC GPE for wakeup on Intel systems"
	kconfig: let 'shell' return enough output for deep path names
	ata: libata-core: Disable TRIM on M88V29
	soc: aspeed: lpc-ctrl: Block error printing on probe defer cases
	xprtrdma: fix pointer derefs in error cases of rpcrdma_ep_create
	drm/rockchip: dw_hdmi: Do not leave clock enabled in error case
	tracing: Fix tp_printk option related with tp_printk_stop_on_boot
	display/amd: decrease message verbosity about watermarks table failure
	drm/amd/display: Cap pflip irqs per max otg number
	drm/amd/display: fix yellow carp wm clamping
	net: usb: qmi_wwan: Add support for Dell DW5829e
	net: macb: Align the dma and coherent dma masks
	kconfig: fix failing to generate auto.conf
	scsi: lpfc: Fix pt2pt NVMe PRLI reject LOGO loop
	EDAC: Fix calculation of returned address and next offset in edac_align_ptr()
	ucounts: Handle wrapping in is_ucounts_overlimit
	ucounts: In set_cred_ucounts assume new->ucounts is non-NULL
	ucounts: Base set_cred_ucounts changes on the real user
	ucounts: Enforce RLIMIT_NPROC not RLIMIT_NPROC+1
	lib/iov_iter: initialize "flags" in new pipe_buffer
	rlimit: Fix RLIMIT_NPROC enforcement failure caused by capability calls in set_user
	ucounts: Move RLIMIT_NPROC handling after set_user
	net: sched: limit TC_ACT_REPEAT loops
	dmaengine: sh: rcar-dmac: Check for error num after setting mask
	dmaengine: stm32-dmamux: Fix PM disable depth imbalance in stm32_dmamux_probe
	dmaengine: sh: rcar-dmac: Check for error num after dma_set_max_seg_size
	tests: fix idmapped mount_setattr test
	i2c: qcom-cci: don't delete an unregistered adapter
	i2c: qcom-cci: don't put a device tree node before i2c_add_adapter()
	dmaengine: ptdma: Fix the error handling path in pt_core_init()
	copy_process(): Move fd_install() out of sighand->siglock critical section
	scsi: qedi: Fix ABBA deadlock in qedi_process_tmf_resp() and qedi_process_cmd_cleanup_resp()
	ice: enable parsing IPSEC SPI headers for RSS
	i2c: brcmstb: fix support for DSL and CM variants
	lockdep: Correct lock_classes index mapping
	Linux 5.15.25

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ib129a0e11f5e82d67563329a5de1b0aef1d87928
2022-02-23 12:30:26 +01:00
Igor Pylypiv
0a01326fdd Revert "module, async: async_synchronize_full() on module init iff async is used"
[ Upstream commit 67d6212afda218d564890d1674bab28e8612170f ]

This reverts commit 774a1221e8.

We need to finish all async code before the module init sequence is
done.  In the reverted commit the PF_USED_ASYNC flag was added to mark a
thread that called async_schedule().  Then the PF_USED_ASYNC flag was
used to determine whether or not async_synchronize_full() needs to be
invoked.  This works when modprobe thread is calling async_schedule(),
but it does not work if module dispatches init code to a worker thread
which then calls async_schedule().

For example, PCI driver probing is invoked from a worker thread based on
a node where device is attached:

	if (cpu < nr_cpu_ids)
		error = work_on_cpu(cpu, local_pci_probe, &ddi);
	else
		error = local_pci_probe(&ddi);

We end up in a situation where a worker thread gets the PF_USED_ASYNC
flag set instead of the modprobe thread.  As a result,
async_synchronize_full() is not invoked and modprobe completes without
waiting for the async code to finish.

The issue was discovered while loading the pm80xx driver:
(scsi_mod.scan=async)

modprobe pm80xx                      worker
...
  do_init_module()
  ...
    pci_call_probe()
      work_on_cpu(local_pci_probe)
                                     local_pci_probe()
                                       pm8001_pci_probe()
                                         scsi_scan_host()
                                           async_schedule()
                                           worker->flags |= PF_USED_ASYNC;
                                     ...
      < return from worker >
  ...
  if (current->flags & PF_USED_ASYNC) <--- false
  	async_synchronize_full();

Commit 21c3c5d280 ("block: don't request module during elevator init")
fixed the deadlock issue which the reverted commit 774a1221e8
("module, async: async_synchronize_full() on module init iff async is
used") tried to fix.

Since commit 0fdff3ec6d ("async, kmod: warn on synchronous
request_module() from async workers") synchronous module loading from
async is not allowed.

Given that the original deadlock issue is fixed and it is no longer
allowed to call synchronous request_module() from async we can remove
PF_USED_ASYNC flag to make module init consistently invoke
async_synchronize_full() unless async module probe is requested.

Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
Reviewed-by: Changyuan Lyu <changyuanl@google.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-23 12:03:07 +01:00
Ramji Jiyani
1694ef383e ANDROID: GKI: Disable security lockdown for unsigned modules
By default with SELinux enabled behavior for unsigned
module loading is same as sig_enforce=1. This causes
loading of unsigned modules fail. All modules in Android
GKI are unsigned except GKI modules. Do not prevent
module loading in case of CONFIG_SIG_MODULE_PROTECT; which
was introduced to change behavior of sig_enforce to allow
unsigned modules but not access to protected symbols.

Bug: 200082547
Bug: 214445388
Fixes: 9ab6a242258a ("ANDROID: GKI: Add module load time protected symbol lookup")
Test: TreeHugger
Signed-off-by: Ramji Jiyani <ramjiyani@google.com>
Change-Id: Iab3113d706cbd7db7a5684897bcafd5671a6d424
2022-01-14 20:01:55 +00:00
Ramji Jiyani
f8bd6cf70d ANDROID: GKI: Add module load time protected symbol lookup
Add CONFIG_MODULE_SIG_PROTECT to enable lookup for the protected
symbols and exports from the build time generated list of symbols
and exports.

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 and do not export the symbols already
  exported by the Android GKI modules. Loading will fail and return
  -EACCES (Permission denied) if symbol access contidions are not met.

Bug: 200082547
Test: Treehugger
Signed-off-by: Ramji Jiyani <ramjiyani@google.com>
Change-Id: Iedb99d8434db82a9c7f18ffd363d84f4b2316c5b
(cherry picked from commit 9ab6a242258a9ac17506b74c6ed7332703d536f4)
2022-01-05 18:38:02 +00:00
Prasad Sodagudi
b2df67a932 ANDROID: android: Create debug_symbols driver
Introduce new API to expose symbols useful for debugging the GKI kernel.
Symbols exported from this driver would be difficult to maintain via the
traditional EXPORT_SYMBOL_GPL.

Bug: 199236943
Change-Id: I1cadb409289ca9ce36b0084efc9ac46f6bec6741
Signed-off-by: Elliot Berman <eberman@codeaurora.org>
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Yogesh Lal <ylal@codeaurora.org>
2021-11-23 11:59:24 +05:30
Kuan-Ying Lee
5ebe162306 ANDROID: module: Add vendor hook
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: 181639260

Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Change-Id: I95b70d7a57994f2548fddfb2290d4c9136f58785
2021-10-29 14:20:11 +08:00
Greg Kroah-Hartman
0b369073d1 Merge 348949d9a4 ("Merge tag 'modules-for-v5.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux") into android-mainline
Steps on the way to 5.15-rc6

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I1ceab8a8f318fd7bb232081930a49f2bf3bc10fa
2021-10-14 14:06:36 +02:00
Arnd Bergmann
0d67e332e6 module: fix clang CFI with MODULE_UNLOAD=n
When CONFIG_MODULE_UNLOAD is disabled, the module->exit member
is not defined, causing a build failure:

kernel/module.c:4493:8: error: no member named 'exit' in 'struct module'
                mod->exit = *exit;

add an #ifdef block around this.

Fixes: cf68fffb66 ("add support for Clang CFI")
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-09-28 12:56:26 +02:00
Greg Kroah-Hartman
3ca4e02658 Merge 4ac6d90867 ("Merge tag 'docs-5.15' of git://git.lwn.net/linux") into android-mainline
Steps on the way to 5.15-rc1

Fixes merge conflicts in:
	scripts/Makefile.lib

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I12b5165860a212fb39c98504a0729f1bab52ab54
2021-09-09 14:00:42 +02:00
Chris Down
3370155737 printk: Userspace format indexing support
We have a number of systems industry-wide that have a subset of their
functionality that works as follows:

1. Receive a message from local kmsg, serial console, or netconsole;
2. Apply a set of rules to classify the message;
3. Do something based on this classification (like scheduling a
   remediation for the machine), rinse, and repeat.

As a couple of examples of places we have this implemented just inside
Facebook, although this isn't a Facebook-specific problem, we have this
inside our netconsole processing (for alarm classification), and as part
of our machine health checking. We use these messages to determine
fairly important metrics around production health, and it's important
that we get them right.

While for some kinds of issues we have counters, tracepoints, or metrics
with a stable interface which can reliably indicate the issue, in order
to react to production issues quickly we need to work with the interface
which most kernel developers naturally use when developing: printk.

Most production issues come from unexpected phenomena, and as such
usually the code in question doesn't have easily usable tracepoints or
other counters available for the specific problem being mitigated. We
have a number of lines of monitoring defence against problems in
production (host metrics, process metrics, service metrics, etc), and
where it's not feasible to reliably monitor at another level, this kind
of pragmatic netconsole monitoring is essential.

As one would expect, monitoring using printk is rather brittle for a
number of reasons -- most notably that the message might disappear
entirely in a new version of the kernel, or that the message may change
in some way that the regex or other classification methods start to
silently fail.

One factor that makes this even harder is that, under normal operation,
many of these messages are never expected to be hit. For example, there
may be a rare hardware bug which one wants to detect if it was to ever
happen again, but its recurrence is not likely or anticipated. This
precludes using something like checking whether the printk in question
was printed somewhere fleetwide recently to determine whether the
message in question is still present or not, since we don't anticipate
that it should be printed anywhere, but still need to monitor for its
future presence in the long-term.

This class of issue has happened on a number of occasions, causing
unhealthy machines with hardware issues to remain in production for
longer than ideal. As a recent example, some monitoring around
blk_update_request fell out of date and caused semi-broken machines to
remain in production for longer than would be desirable.

Searching through the codebase to find the message is also extremely
fragile, because many of the messages are further constructed beyond
their callsite (eg. btrfs_printk and other module-specific wrappers,
each with their own functionality). Even if they aren't, guessing the
format and formulation of the underlying message based on the aesthetics
of the message emitted is not a recipe for success at scale, and our
previous issues with fleetwide machine health checking demonstrate as
much.

This provides a solution to the issue of silently changed or deleted
printks: we record pointers to all printk format strings known at
compile time into a new .printk_index section, both in vmlinux and
modules. At runtime, this can then be iterated by looking at
<debugfs>/printk/index/<module>, which emits the following format, both
readable by humans and able to be parsed by machines:

    $ head -1 vmlinux; shuf -n 5 vmlinux
    # <level[,flags]> filename:line function "format"
    <5> block/blk-settings.c:661 disk_stack_limits "%s: Warning: Device %s is misaligned\n"
    <4> kernel/trace/trace.c:8296 trace_create_file "Could not create tracefs '%s' entry\n"
    <6> arch/x86/kernel/hpet.c:144 _hpet_print_config "hpet: %s(%d):\n"
    <6> init/do_mounts.c:605 prepare_namespace "Waiting for root device %s...\n"
    <6> drivers/acpi/osl.c:1410 acpi_no_auto_serialize_setup "ACPI: auto-serialization disabled\n"

This mitigates the majority of cases where we have a highly-specific
printk which we want to match on, as we can now enumerate and check
whether the format changed or the printk callsite disappeared entirely
in userspace. This allows us to catch changes to printks we monitor
earlier and decide what to do about it before it becomes problematic.

There is no additional runtime cost for printk callers or printk itself,
and the assembly generated is exactly the same.

Signed-off-by: Chris Down <chris@chrisdown.name>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Jessica Yu <jeyu@kernel.org> # for module.{c,h}
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/e42070983637ac5e384f17fbdbe86d19c7b212a5.1623775748.git.chris@chrisdown.name
2021-07-19 11:57:48 +02:00
Lee Jones
a8b636db7d Merge tag 'v5.14-rc1' into android-mainline
Linux 5.14-rc1

Change-Id: I9765cd4581f6683a6fca3580667017fff9cbaa2b
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2021-07-13 10:02:04 +01:00
Stephen Boyd
9294523e37 module: add printk formats to add module build ID to stacktraces
Let's make kernel stacktraces easier to identify by including the build
ID[1] of a module if the stacktrace is printing a symbol from a module.
This makes it simpler for developers to locate a kernel module's full
debuginfo for a particular stacktrace.  Combined with
scripts/decode_stracktrace.sh, a developer can download the matching
debuginfo from a debuginfod[2] server and find the exact file and line
number for the functions plus offsets in a stacktrace that match the
module.  This is especially useful for pstore crash debugging where the
kernel crashes are recorded in something like console-ramoops and the
recovery kernel/modules are different or the debuginfo doesn't exist on
the device due to space concerns (the debuginfo can be too large for space
limited devices).

Originally, I put this on the %pS format, but that was quickly rejected
given that %pS is used in other places such as ftrace where build IDs
aren't meaningful.  There was some discussions on the list to put every
module build ID into the "Modules linked in:" section of the stacktrace
message but that quickly becomes very hard to read once you have more than
three or four modules linked in.  It also provides too much information
when we don't expect each module to be traversed in a stacktrace.  Having
the build ID for modules that aren't important just makes things messy.
Splitting it to multiple lines for each module quickly explodes the number
of lines printed in an oops too, possibly wrapping the warning off the
console.  And finally, trying to stash away each module used in a
callstack to provide the ID of each symbol printed is cumbersome and would
require changes to each architecture to stash away modules and return
their build IDs once unwinding has completed.

Instead, we opt for the simpler approach of introducing new printk formats
'%pS[R]b' for "pointer symbolic backtrace with module build ID" and '%pBb'
for "pointer backtrace with module build ID" and then updating the few
places in the architecture layer where the stacktrace is printed to use
this new format.

Before:

 Call trace:
  lkdtm_WARNING+0x28/0x30 [lkdtm]
  direct_entry+0x16c/0x1b4 [lkdtm]
  full_proxy_write+0x74/0xa4
  vfs_write+0xec/0x2e8

After:

 Call trace:
  lkdtm_WARNING+0x28/0x30 [lkdtm 6c2215028606bda50de823490723dc4bc5bf46f9]
  direct_entry+0x16c/0x1b4 [lkdtm 6c2215028606bda50de823490723dc4bc5bf46f9]
  full_proxy_write+0x74/0xa4
  vfs_write+0xec/0x2e8

[akpm@linux-foundation.org: fix build with CONFIG_MODULES=n, tweak code layout]
[rdunlap@infradead.org: fix build when CONFIG_MODULES is not set]
  Link: https://lkml.kernel.org/r/20210513171510.20328-1-rdunlap@infradead.org
[akpm@linux-foundation.org: make kallsyms_lookup_buildid() static]
[cuibixuan@huawei.com: fix build error when CONFIG_SYSFS is disabled]
  Link: https://lkml.kernel.org/r/20210525105049.34804-1-cuibixuan@huawei.com

Link: https://lkml.kernel.org/r/20210511003845.2429846-6-swboyd@chromium.org
Link: https://fedoraproject.org/wiki/Releases/FeatureBuildId [1]
Link: https://sourceware.org/elfutils/Debuginfod.html [2]
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-08 11:48:22 -07:00
Linus Torvalds
a931dd33d3 Merge tag 'modules-for-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:

 - Fix incorrect logic in module_kallsyms_on_each_symbol()

 - Fix for a Coccinelle warning

* tag 'modules-for-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: correctly exit module_kallsyms_on_each_symbol when fn() != 0
  kernel/module: Use BUG_ON instead of if condition followed by BUG
2021-07-07 11:41:32 -07:00
Greg Kroah-Hartman
d814dfca93 Merge 625acffd7a ("Merge tag 's390-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux") into android-mainline
Steps on the way to 5.13-final

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I792b77ece0440ec9d609829dac75d5ca4a5b1671
2021-06-28 07:27:46 +02:00
Mimi Zohar
0c18f29aae module: limit enabling module.sig_enforce
Irrespective as to whether CONFIG_MODULE_SIG is configured, specifying
"module.sig_enforce=1" on the boot command line sets "sig_enforce".
Only allow "sig_enforce" to be set when CONFIG_MODULE_SIG is configured.

This patch makes the presence of /sys/module/module/parameters/sig_enforce
dependent on CONFIG_MODULE_SIG=y.

Fixes: fda784e50a ("module: export module signature enforcement status")
Reported-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
Tested-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-22 11:13:19 -07:00
Greg Kroah-Hartman
b1065ab819 Merge tag 'v5.13-rc4' into android-mainline
Linux 5.13-rc4

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I05336d3226a208ac657fcfd4d39b418ad1dba1bd
2021-06-01 09:10:12 +02:00
Jon Mediero
2c0f0f3639 module: correctly exit module_kallsyms_on_each_symbol when fn() != 0
Commit 013c1667cf ("kallsyms: refactor
{,module_}kallsyms_on_each_symbol") replaced the return inside the
nested loop with a break, changing the semantics of the function: the
break only exits the innermost loop, so the code continues iterating the
symbols of the next module instead of exiting.

Fixes: 013c1667cf ("kallsyms: refactor {,module_}kallsyms_on_each_symbol")
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jon Mediero <jmdr@disroot.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-05-26 14:55:45 +02:00
Jessica Yu
055f23b74b module: check for exit sections in layout_sections() instead of module_init_section()
Previously, when CONFIG_MODULE_UNLOAD=n, the module loader just does not
attempt to load exit sections since it never expects that any code in those
sections will ever execute. However, dynamic code patching (alternatives,
jump_label and static_call) can have sites in __exit code, even if __exit is
never executed. Therefore __exit must be present at runtime, at least for as
long as __init code is.

Commit 33121347fb ("module: treat exit sections the same as init
sections when !CONFIG_MODULE_UNLOAD") solves the requirements of
jump_labels and static_calls by putting the exit sections in the init
region of the module so that they are at least present at init, and
discarded afterwards. It does this by including a check for exit
sections in module_init_section(), so that it also returns true for exit
sections, and the module loader will automatically sort them in the init
region of the module.

However, the solution there was not completely arch-independent. ARM is
a special case where it supplies its own module_{init, exit}_section()
functions. Instead of pushing the exit section checks into
module_init_section(), just implement the exit section check in
layout_sections(), so that we don't have to touch arch-dependent code.

Fixes: 33121347fb ("module: treat exit sections the same as init sections when !CONFIG_MODULE_UNLOAD")
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-05-17 09:48:24 +02:00
zhouchuangao
02b2fb455b kernel/module: Use BUG_ON instead of if condition followed by BUG
Fix the following coccinelle report:

kernel/module.c:1018:2-5:
WARNING: Use BUG_ON instead of if condition followed by BUG.

BUG_ON uses unlikely in if(). Through disassembly, we can see that
brk #0x800 is compiled to the end of the function.
As you can see below:
    ......
    ffffff8008660bec:   d65f03c0    ret
    ffffff8008660bf0:   d4210000    brk #0x800

Usually, the condition in if () is not satisfied. For the
multi-stage pipeline, we do not need to perform fetch decode
and excute operation on brk instruction.

In my opinion, this can improve the efficiency of the
multi-stage pipeline.

Signed-off-by: zhouchuangao <zhouchuangao@vivo.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-05-14 09:50:56 +02:00
Lee Jones
163e8b4fec Merge d652502ef4 Merge tag 'ovl-update-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs into android-mainline
A tiny step en route to v5.13-rc1

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Change-Id: I049e80976042ebffc90bb080f09da0afcfd48d77
2021-05-12 15:54:32 +01:00
Linus Torvalds
65c61de9d0 Merge tag 'modules-for-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
 "Fix an age old bug involving jump_calls and static_labels when
  CONFIG_MODULE_UNLOAD=n.

  When CONFIG_MODULE_UNLOAD=n, it means you can't unload modules, so
  normally the __exit sections of a module are not loaded at all.
  However, dynamic code patching (jump_label, static_call, alternatives)
  can have sites in __exit sections even if __exit is never executed.

  Reported by Peter Zijlstra:
     'Alternatives, jump_labels and static_call all can have relocations
      into __exit code. Not loading it at all would be BAD.'

  Therefore, load the __exit sections even when CONFIG_MODULE_UNLOAD=n,
  and discard them after init"

* tag 'modules-for-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: treat exit sections the same as init sections when !CONFIG_MODULE_UNLOAD
2021-04-30 12:29:36 -07:00
Lee Jones
7561514944 Merge commit e7c6e405e1 ("Fix misc new gcc warnings") into android-mainline
Steps on the way to 5.13-rc1

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Change-Id: Iff6fb6b3991943905d20a8b40e2b2dd87c0d792b
2021-04-29 10:20:06 +01:00
Sami Tolvanen
cf68fffb66 add support for Clang CFI
This change adds support for Clang’s forward-edge Control Flow
Integrity (CFI) checking. With CONFIG_CFI_CLANG, the compiler
injects a runtime check before each indirect function call to ensure
the target is a valid function with the correct static type. This
restricts possible call targets and makes it more difficult for
an attacker to exploit bugs that allow the modification of stored
function pointers. For more details, see:

  https://clang.llvm.org/docs/ControlFlowIntegrity.html

Clang requires CONFIG_LTO_CLANG to be enabled with CFI to gain
visibility to possible call targets. Kernel modules are supported
with Clang’s cross-DSO CFI mode, which allows checking between
independently compiled components.

With CFI enabled, the compiler injects a __cfi_check() function into
the kernel and each module for validating local call targets. For
cross-module calls that cannot be validated locally, the compiler
calls the global __cfi_slowpath_diag() function, which determines
the target module and calls the correct __cfi_check() function. This
patch includes a slowpath implementation that uses __module_address()
to resolve call targets, and with CONFIG_CFI_CLANG_SHADOW enabled, a
shadow map that speeds up module look-ups by ~3x.

Clang implements indirect call checking using jump tables and
offers two methods of generating them. With canonical jump tables,
the compiler renames each address-taken function to <function>.cfi
and points the original symbol to a jump table entry, which passes
__cfi_check() validation. This isn’t compatible with stand-alone
assembly code, which the compiler doesn’t instrument, and would
result in indirect calls to assembly code to fail. Therefore, we
default to using non-canonical jump tables instead, where the compiler
generates a local jump table entry <function>.cfi_jt for each
address-taken function, and replaces all references to the function
with the address of the jump table entry.

Note that because non-canonical jump table addresses are local
to each component, they break cross-module function address
equality. Specifically, the address of a global function will be
different in each module, as it's replaced with the address of a local
jump table entry. If this address is passed to a different module,
it won’t match the address of the same function taken there. This
may break code that relies on comparing addresses passed from other
components.

CFI checking can be disabled in a function with the __nocfi attribute.
Additionally, CFI can be disabled for an entire compilation unit by
filtering out CC_FLAGS_CFI.

By default, CFI failures result in a kernel panic to stop a potential
exploit. CONFIG_CFI_PERMISSIVE enables a permissive mode, where the
kernel prints out a rate-limited warning instead, and allows execution
to continue. This option is helpful for locating type mismatches, but
should only be enabled during development.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-2-samitolvanen@google.com
2021-04-08 16:04:20 -07:00
Jessica Yu
33121347fb module: treat exit sections the same as init sections when !CONFIG_MODULE_UNLOAD
Dynamic code patching (alternatives, jump_label and static_call) can
have sites in __exit code, even it __exit is never executed. Therefore
__exit must be present at runtime, at least for as long as __init code
is.

Additionally, for jump_label and static_call, the __exit sites must also
identify as within_module_init(), such that the infrastructure is aware
to never touch them after module init -- alternatives are only ran once
at init and hence don't have this particular constraint.

By making __exit identify as __init for MODULE_UNLOAD, the above is
satisfied.

So, when !CONFIG_MODULE_UNLOAD, the section ordering should look like the
following, with the .exit sections moved to the init region of the module.

Core section allocation order:
 	.text
 	.rodata
 	__ksymtab_gpl
 	__ksymtab_strings
 	.note.* sections
 	.bss
 	.data
 	.gnu.linkonce.this_module
 Init section allocation order:
 	.init.text
 	.exit.text
 	.symtab
 	.strtab

[jeyu: thanks to Peter Zijlstra for most of changelog]

Link: https://lore.kernel.org/lkml/YFiuphGw0RKehWsQ@gunter/
Link: https://lore.kernel.org/r/20210323142756.11443-1-jeyu@kernel.org
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-03-29 13:08:53 +02:00
Greg Kroah-Hartman
368ecbcb2f Merge 21a6ab2131 ("Merge tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux") into android-mainline
Steps on the way to 5.12-rc1

Resolves conflicts in:
	include/linux/module.h

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I44772d65a5d6b1c5f4c33905554092c2cdc5b210
2021-03-06 08:45:21 +01:00
Will McVicker
4b9c11a373 ANDROID: modules: introduce the MODULE_SCMVERSION config
Config MODULE_SCMVERSION introduces a new module attribute --
`scmversion` -- which can be used to identify a given module's SCM
version.  This is very useful for developers that update their kernel
independently from their kernel modules or vice-versa since the SCM
version provided by UTS_RELEASE (`uname -r`) will now differ from the
module's vermagic attribute.

For example, we have a CI setup that tests new kernel changes on the
hikey960 and db845c devices without updating their kernel modules. When
these tests fail, we need to be able to identify the exact device
configuration the test was using. By including MODULE_SCMVERSION, we can
identify the exact kernel and modules' SCM versions for debugging the
failures.

Additionally, by exposing the SCM version via the sysfs node
/sys/module/MODULENAME/scmversion, one can also verify the SCM versions
of the modules loaded from the initramfs. Currently, modinfo can only
retrieve module attributes from the module's ko on disk and not from the
actual module that is loaded in RAM.

You can retrieve the SCM version in two ways,

1) By using modinfo:
    > modinfo -F scmversion MODULENAME
2) By module sysfs node:
    > cat /sys/module/MODULENAME/scmversion

Bug: 180027765
Link: https://lkml.org/lkml/2021/1/21/1388
Signed-off-by: Will McVicker <willmcvicker@google.com>
Change-Id: Ib7c72c72f95c4545adb7cd4e842729557039ce3a
2021-02-12 17:19:18 -08:00
Dan Carpenter
1e80d9cb57 module: potential uninitialized return in module_kallsyms_on_each_symbol()
Smatch complains that:

	kernel/module.c:4472 module_kallsyms_on_each_symbol()
        error: uninitialized symbol 'ret'.

This warning looks like it could be correct if the &modules list is
empty.

Fixes: 013c1667cf ("kallsyms: refactor {,module_}kallsyms_on_each_symbol")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-10 16:57:04 +01:00
Christoph Hellwig
367948220f module: remove EXPORT_UNUSED_SYMBOL*
EXPORT_UNUSED_SYMBOL* is not actually used anywhere.  Remove the
unused functionality as we generally just remove unused code anyway.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:28:07 +01:00
Christoph Hellwig
f1c3d73e97 module: remove EXPORT_SYMBOL_GPL_FUTURE
As far as I can tell this has never been used at all, and certainly
not any time recently.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:28:02 +01:00
Christoph Hellwig
00cc2c1cd3 module: move struct symsearch to module.c
struct symsearch is only used inside of module.h, so move the definition
out of module.h.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:27:43 +01:00
Christoph Hellwig
0b96615cdc module: pass struct find_symbol_args to find_symbol
Simplify the calling convention by passing the find_symbol_args structure
to find_symbol instead of initializing it inside the function.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:25:19 +01:00
Christoph Hellwig
71e4b309dc module: merge each_symbol_section into find_symbol
each_symbol_section is only called by find_symbol, so merge the two
functions.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:25:07 +01:00
Christoph Hellwig
a7c38f2cd3 module: remove each_symbol_in_section
each_symbol_in_section just contains a trivial loop over its arguments.
Just open code the loop in the two callers.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:24:54 +01:00
Christoph Hellwig
922f2a7c82 module: mark module_mutex static
Except for two lockdep asserts module_mutex is only used in module.c.
Remove the two asserts given that the functions they are in are not
exported and just called from the module code, and mark module_mutex
static.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:24:26 +01:00
Christoph Hellwig
3e3552056a kallsyms: only build {,module_}kallsyms_on_each_symbol when required
kallsyms_on_each_symbol and module_kallsyms_on_each_symbol are only used
by the livepatching code, so don't build them if livepatching is not
enabled.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:24:04 +01:00
Christoph Hellwig
013c1667cf kallsyms: refactor {,module_}kallsyms_on_each_symbol
Require an explicit call to module_kallsyms_on_each_symbol to look
for symbols in modules instead of the call from kallsyms_on_each_symbol,
and acquire module_mutex inside of module_kallsyms_on_each_symbol instead
of leaving that up to the caller.  Note that this slightly changes the
behavior for the livepatch code in that the symbols from vmlinux are not
iterated anymore if objname is set, but that actually is the desired
behavior in this case.

Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:22:08 +01:00
Christoph Hellwig
a006050575 module: use RCU to synchronize find_module
Allow for a RCU-sched critical section around find_module, following
the lower level find_module_all helper, and switch the two callers
outside of module.c to use such a RCU-sched critical section instead
of module_mutex.

Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:21:40 +01:00
Christoph Hellwig
089049f6c9 module: unexport find_module and module_mutex
find_module is not used by modular code any more, and random driver code
has no business calling it to start with.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08 12:21:16 +01:00
Frank van der Linden
ec2a29593c module: harden ELF info handling
5fdc7db644 ("module: setup load info before module_sig_check()")
moved the ELF setup, so that it was done before the signature
check. This made the module name available to signature error
messages.

However, the checks for ELF correctness in setup_load_info
are not sufficient to prevent bad memory references due to
corrupted offset fields, indices, etc.

So, there's a regression in behavior here: a corrupt and unsigned
(or badly signed) module, which might previously have been rejected
immediately, can now cause an oops/crash.

Harden ELF handling for module loading by doing the following:

- Move the signature check back up so that it comes before ELF
  initialization. It's best to do the signature check to see
  if we can trust the module, before using the ELF structures
  inside it. This also makes checks against info->len
  more accurate again, as this field will be reduced by the
  length of the signature in mod_check_sig().

  The module name is now once again not available for error
  messages during the signature check, but that seems like
  a fair tradeoff.

- Check if sections have offset / size fields that at least don't
  exceed the length of the module.

- Check if sections have section name offsets that don't fall
  outside the section name table.

- Add a few other sanity checks against invalid section indices,
  etc.

This is not an exhaustive consistency check, but the idea is to
at least get through the signature and blacklist checks without
crashing because of corrupted ELF info, and to error out gracefully
for most issues that would have caused problems later on.

Fixes: 5fdc7db644 ("module: setup load info before module_sig_check()")
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-01-19 10:24:45 +01:00
Fangrui Song
ebfac7b778 module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbols
clang-12 -fno-pic (since
a084c0388e)
can emit `call __stack_chk_fail@PLT` instead of `call __stack_chk_fail`
on x86.  The two forms should have identical behaviors on x86-64 but the
former causes GNU as<2.37 to produce an unreferenced undefined symbol
_GLOBAL_OFFSET_TABLE_.

(On x86-32, there is an R_386_PC32 vs R_386_PLT32 difference but the
linker behavior is identical as far as Linux kernel is concerned.)

Simply ignore _GLOBAL_OFFSET_TABLE_ for now, like what
scripts/mod/modpost.c:ignore_undef_symbol does. This also fixes the
problem for gcc/clang -fpie and -fpic, which may emit `call foo@PLT` for
external function calls on x86.

Note: ld -z defs and dynamic loaders do not error for unreferenced
undefined symbols so the module loader is reading too much.  If we ever
need to ignore more symbols, the code should be refactored to ignore
unreferenced symbols.

Cc: <stable@vger.kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/1250
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=27178
Reported-by: Marco Elver <elver@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Marco Elver <elver@google.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-01-18 10:45:42 +01:00
Linus Torvalds
312dcaf967 Merge tag 'modules-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 5.11 merge window:

   - Fix a race condition between systemd/udev and the module loader.

     The module loader was sending a uevent before the module was fully
     initialized (i.e., before its init function has been called). This
     means udev can start processing the module uevent before the module
     has finished initializing, and some udev rules expect that the
     module has initialized already upon receiving the uevent.

     This resulted in some systemd mount units failing if udev processes
     the event faster than the module can finish init. This is fixed by
     delaying the uevent until after the module has called its init
     routine.

   - Make the linker array sections for kernel params and module version
     attributes more robust by switching to use the alignment of the
     type in question.

     Namely, linker section arrays will be constructed using the
     alignment required by the struct (using __alignof__()) as opposed
     to a specific value such as sizeof(void *) or sizeof(long). This is
     less likely to cause breakages should the size of the type ever
     change (Johan Hovold)

   - Fix module state inconsistency by setting it back to GOING when a
     module fails to load and is on its way out (Miroslav Benes)

   - Some comment and code cleanups (Sergey Shtylyov)"

* tag 'modules-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: delay kobject uevent until after module init call
  module: drop semicolon from version macro
  init: use type alignment for kernel parameters
  params: clean up module-param macros
  params: use type alignment for kernel parameters
  params: drop redundant "unused" attributes
  module: simplify version-attribute handling
  module: drop version-attribute alignment
  module: fix comment style
  module: add more 'kernel-doc' comments
  module: fix up 'kernel-doc' comments
  module: only handle errors with the *switch* statement in module_sig_check()
  module: avoid *goto*s in module_sig_check()
  module: merge repetitive strings in module_sig_check()
  module: set MODULE_STATE_GOING state when a module fails to load
2020-12-17 13:01:31 -08:00
Jessica Yu
38dc717e97 module: delay kobject uevent until after module init call
Apparently there has been a longstanding race between udev/systemd and
the module loader. Currently, the module loader sends a uevent right
after sysfs initialization, but before the module calls its init
function. However, some udev rules expect that the module has
initialized already upon receiving the uevent.

This race has been triggered recently (see link in references) in some
systemd mount unit files. For instance, the configfs module creates the
/sys/kernel/config mount point in its init function, however the module
loader issues the uevent before this happens. sys-kernel-config.mount
expects to be able to mount /sys/kernel/config upon receipt of the
module loading uevent, but if the configfs module has not called its
init function yet, then this directory will not exist and the mount unit
fails. A similar situation exists for sys-fs-fuse-connections.mount, as
the fuse sysfs mount point is created during the fuse module's init
function. If udev is faster than module initialization then the mount
unit would fail in a similar fashion.

To fix this race, delay the module KOBJ_ADD uevent until after the
module has finished calling its init routine.

References: https://github.com/systemd/systemd/issues/17586
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-By: Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2020-12-09 09:42:47 +01:00
Andrii Nakryiko
2fe8890848 bpf: Keep module's btf_data_size intact after load
Having real btf_data_size stored in struct module is benefitial to quickly
determine which kernel modules have associated BTF object and which don't.
There is no harm in keeping this info, as opposed to keeping invalid pointer.

Fixes: 607c543f93 ("bpf: Sanitize BTF data pointer after module is loaded")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-3-andrii@kernel.org
2020-12-03 17:38:20 -08:00
Andrii Nakryiko
607c543f93 bpf: Sanitize BTF data pointer after module is loaded
Given .BTF section is not allocatable, it will get trimmed after module is
loaded. BPF system handles that properly by creating an independent copy of
data. But prevent any accidental misused by resetting the pointer to BTF data.

Fixes: 36e68442d1 ("bpf: Load and verify kernel module BTFs")
Suggested-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jessica Yu <jeyu@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/bpf/20201121070829.2612884-2-andrii@kernel.org
2020-11-25 00:05:21 +01:00
Andrii Nakryiko
36e68442d1 bpf: Load and verify kernel module BTFs
Add kernel module listener that will load/validate and unload module BTF.
Module BTFs gets ID generated for them, which makes it possible to iterate
them with existing BTF iteration API. They are given their respective module's
names, which will get reported through GET_OBJ_INFO API. They are also marked
as in-kernel BTFs for tooling to distinguish them from user-provided BTFs.

Also, similarly to vmlinux BTF, kernel module BTFs are exposed through
sysfs as /sys/kernel/btf/<module-name>. This is convenient for user-space
tools to inspect module BTF contents and dump their types with existing tools:

[vmuser@archvm bpf]$ ls -la /sys/kernel/btf
total 0
drwxr-xr-x  2 root root       0 Nov  4 19:46 .
drwxr-xr-x 13 root root       0 Nov  4 19:46 ..

...

-r--r--r--  1 root root     888 Nov  4 19:46 irqbypass
-r--r--r--  1 root root  100225 Nov  4 19:46 kvm
-r--r--r--  1 root root   35401 Nov  4 19:46 kvm_intel
-r--r--r--  1 root root     120 Nov  4 19:46 pcspkr
-r--r--r--  1 root root     399 Nov  4 19:46 serio_raw
-r--r--r--  1 root root 4094095 Nov  4 19:46 vmlinux

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/bpf/20201110011932.3201430-5-andrii@kernel.org
2020-11-10 15:25:53 -08:00
Sergey Shtylyov
24b9f0d220 module: fix comment style
Many comments in this module do not comply with the preferred multi-line
comment style as reported by 'scripts/checkpatch.pl':

WARNING: Block comments use * on subsequent lines
WARNING: Block comments use a trailing */ on a separate line

Fix those comments, along with (unreported for some reason?) the starts
of the multi-line comments not being /* on their own line...

Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2020-11-09 14:28:12 +01:00
Sergey Shtylyov
2541743e99 module: add more 'kernel-doc' comments
Some functions have the proper 'kernel-doc' comments but these don't start
with proper /** -- fix that, along with adding () to the function name on
the following lines to fully comply with the 'kernel-doc' format.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2020-11-09 13:47:42 +01:00
Sergey Shtylyov
24389b610b module: fix up 'kernel-doc' comments
Some 'kernel-doc' function comments do not fully comply with the specified
format due to:

- missing () after the function name;

- "RETURNS:"/"Returns:" instead of "Return:" when documenting the function's
  result.

- empty line before describing the function's arguments.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2020-11-09 13:46:58 +01:00
Sergey Shtylyov
076aa52e40 module: only handle errors with the *switch* statement in module_sig_check()
Let's handle the successful call of mod_verify_sig() right after that call,
making the *switch* statement only handle the real errors, and then move
the comment from the first *case* before *switch* itself and the comment
before *default* after it.  Fix the comment style, add article/comma/dash,
spell out "nomem" as "lack of memory" in these comments, while at it...

Suggested-by: Joe Perches <joe@perches.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2020-11-04 15:31:29 +01:00
Sergey Shtylyov
10ccd1abb8 module: avoid *goto*s in module_sig_check()
Let's move the common handling of the non-fatal errors after the *switch*
statement -- this avoids *goto*s inside that *switch*...

Suggested-by: Joe Perches <joe@perches.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2020-11-04 15:31:28 +01:00