commit 28438794ab upstream.
Since commit f02e8a6596 ("module: Sort exported symbols"),
EXPORT_SYMBOL* is placed in the individual section ___ksymtab(_gpl)+<sym>
(3 leading underscores instead of 2).
Since then, modpost cannot detect the bad combination of EXPORT_SYMBOL
and __init/__exit.
Fix the .fromsec field.
Fixes: f02e8a6596 ("module: Sort exported symbols")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d6b732666a ]
The return value of is_arm_mapping_symbol() is unpredictable when "$"
is passed in.
strchr(3) says:
The strchr() and strrchr() functions return a pointer to the matched
character or NULL if the character is not found. The terminating null
byte is considered part of the string, so that if c is specified as
'\0', these functions return a pointer to the terminator.
When str[1] is '\0', strchr("axtd", str[1]) is not NULL, and str[2] is
referenced (i.e. buffer overrun).
Test code
---------
char str1[] = "abc";
char str2[] = "ab";
strcpy(str1, "$");
strcpy(str2, "$");
printf("test1: %d\n", is_arm_mapping_symbol(str1));
printf("test2: %d\n", is_arm_mapping_symbol(str2));
Result
------
test1: 0
test2: 1
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b5beffa20d ]
With the `-z unique-symbol` linker flag or any similar mechanism,
it is possible to trigger the following:
ERROR: modpost: "param_set_uint.0" [vmlinux] is a static EXPORT_SYMBOL
The reason is that for now the condition from remove_dot():
if (m && (s[n + m] == '.' || s[n + m] == 0))
which was designed to test if it's a dot or a '\0' after the suffix
is never satisfied.
This is due to that `s[n + m]` always points to the last digit of a
numeric suffix, not on the symbol next to it (from a custom debug
print added to modpost):
param_set_uint.0, s[n + m] is '0', s[n + m + 1] is '\0'
So it's off-by-one and was like that since 2014.
Fix this for the sake of any potential upcoming features, but don't
bother stable-backporting, as it's well hidden -- apart from that
LD flag, it can be triggered only with GCC LTO which never landed
upstream.
Fixes: fcd38ed0ff ("scripts: modpost: fix compilation warning")
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a4d26f1a09 ]
During development of a serial console driver with a gcc 8.2.0
toolchain for RISC-V, the following modpost warning appeared:
----
WARNING: vmlinux.o(.data+0x19b10): Section mismatch in reference from the variable .LANCHOR1 to the function .init.text:sifive_serial_console_setup()
The variable .LANCHOR1 references
the function __init sifive_serial_console_setup()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console
----
".LANCHOR1" is an ELF local symbol, automatically created by gcc's section
anchor generation code:
https://gcc.gnu.org/onlinedocs/gccint/Anchored-Addresses.htmlhttps://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/varasm.c;h=cd9591a45617464946dcf9a126dde277d9de9804;hb=9fb89fa845c1b2e0a18d85ada0b077c84508ab78#l7473
This was verified by compiling the kernel with -fno-section-anchors
and observing that the ".LANCHOR1" ELF local symbol disappeared, and
modpost no longer warned about the section mismatch. The serial
driver code idiom triggering the warning is standard Linux serial
driver practice that has a specific whitelist inclusion in modpost.c.
I'm neither a modpost nor an ELF expert, but naively, it doesn't seem
useful for modpost to report section mismatch warnings caused by ELF
local symbols by default. Local symbols have compiler-generated
names, and thus bypass modpost's whitelisting algorithm, which relies
on the presence of a non-autogenerated symbol name. This increases
the likelihood that false positive warnings will be generated (as in
the above case).
Thus, disable section mismatch reporting on ELF local symbols. The
rationale here is similar to that of commit 2e3a10a155 ("ARM: avoid
ARM binutils leaking ELF local symbols") and of similar code already
present in modpost.c:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/mod/modpost.c?h=v4.19-rc4&id=7876320f88802b22d4e2daf7eb027dd14175a0f8#n1256
This third version of the patch implements a suggestion from Masahiro
Yamada <yamada.masahiro@socionext.com> to restructure the code as an
additional pattern matching step inside secref_whitelist(), and
further improves the patch description.
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ec91e78d37 upstream.
Commit e49ce14150 ("modpost: use linker section to generate table.")
was not so cool as we had expected first; it ended up with ugly section
hacks when commit dd2a3acaec ("mod/file2alias: make modpost compile
on darwin again") came in.
Given a certain degree of unknowledge about the link stage of host
programs, I really want to see simple, stupid table lookup so that
this works in the same way regardless of the underlying executable
format.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Mathieu Malaterre <malat@debian.org>
[nc: Omit rpmsg, sdw, tbsvc, and typec as they don't exist here]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5818c683a6 ]
If an ARM mapping symbol shares an address with a valid symbol,
find_elf_symbol can currently return the mapping symbol instead, as the
symbol is not validated. This can result in confusing warnings:
WARNING: vmlinux.o(.text+0x18f4028): Section mismatch in reference
from the function set_reset_devices() to the variable .init.text:$x.0
This change adds a call to is_valid_name to find_elf_symbol, similarly
to how it's already used in find_elf_symbol2.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
With CONFIG_LTO_CLANG, clang generates LLVM IR instead of ELF object
files. As empty.o is used for probing target properties, disable LTO
for it to produce an object file instead.
Bug: 62093296
Bug: 67506682
Change-Id: I0c7ac7ee0134465cac4a8c3a9c7e8b6347076a2b
(am from https://patchwork.kernel.org/patch/10060317/)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Changes in 4.9.81
powerpc/pseries: Add H_GET_CPU_CHARACTERISTICS flags & wrapper
powerpc/64: Add macros for annotating the destination of rfid/hrfid
powerpc/64: Convert fast_exception_return to use RFI_TO_USER/KERNEL
powerpc/64: Convert the syscall exit path to use RFI_TO_USER/KERNEL
powerpc/64s: Convert slb_miss_common to use RFI_TO_USER/KERNEL
powerpc/64s: Add support for RFI flush of L1-D cache
powerpc/64s: Support disabling RFI flush with no_rfi_flush and nopti
powerpc/pseries: Query hypervisor for RFI flush settings
powerpc/powernv: Check device-tree for RFI flush settings
powerpc/64s: Wire up cpu_show_meltdown()
powerpc/64s: Allow control of RFI flush via debugfs
auxdisplay: img-ascii-lcd: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE
pinctrl: pxa: pxa2xx: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE
ASoC: pcm512x: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE
kaiser: fix intel_bts perf crashes
x86/pti: Make unpoison of pgd for trusted boot work for real
kaiser: allocate pgd with order 0 when pti=off
serial: core: mark port as initialized after successful IRQ change
ip6mr: fix stale iterator
net: igmp: add a missing rcu locking section
qlcnic: fix deadlock bug
qmi_wwan: Add support for Quectel EP06
r8169: fix RTL8168EP take too long to complete driver initialization.
tcp: release sk_frag.page in tcp_disconnect
vhost_net: stop device during reset owner
tcp_bbr: fix pacing_gain to always be unity when using lt_bw
cls_u32: add missing RCU annotation.
ipv6: Fix SO_REUSEPORT UDP socket with implicit sk_ipv6only
soreuseport: fix mem leak in reuseport_add_sock()
x86/asm: Fix inline asm call constraints for GCC 4.4
x86/microcode/AMD: Do not load when running on a hypervisor
media: soc_camera: soc_scale_crop: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE
b43: Add missing MODULE_FIRMWARE()
KEYS: encrypted: fix buffer overread in valid_master_desc()
x86/retpoline: Remove the esp/rsp thunk
KVM: x86: Make indirect calls in emulator speculation safe
KVM: VMX: Make indirect call speculation safe
module/retpoline: Warn about missing retpoline in module
x86/cpufeatures: Add CPUID_7_EDX CPUID leaf
x86/cpufeatures: Add Intel feature bits for Speculation Control
x86/cpufeatures: Add AMD feature bits for Speculation Control
x86/msr: Add definitions for new speculation control MSRs
x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown
x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes
x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support
x86/nospec: Fix header guards names
x86/bugs: Drop one "mitigation" from dmesg
x86/cpu/bugs: Make retpoline module warning conditional
x86/cpufeatures: Clean up Spectre v2 related CPUID flags
x86/retpoline: Simplify vmexit_fill_RSB()
x86/spectre: Check CONFIG_RETPOLINE in command line parser
x86/entry/64: Remove the SYSCALL64 fast path
x86/entry/64: Push extra regs right away
x86/asm: Move 'status' from thread_struct to thread_info
Documentation: Document array_index_nospec
array_index_nospec: Sanitize speculative array de-references
x86: Implement array_index_mask_nospec
x86: Introduce barrier_nospec
x86: Introduce __uaccess_begin_nospec() and uaccess_try_nospec
x86/usercopy: Replace open coded stac/clac with __uaccess_{begin, end}
x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec
x86/get_user: Use pointer masking to limit speculation
x86/syscall: Sanitize syscall table de-references under speculation
vfs, fdtable: Prevent bounds-check bypass via speculative execution
nl80211: Sanitize array index in parse_txq_params
x86/spectre: Report get_user mitigation for spectre_v1
x86/spectre: Fix spelling mistake: "vunerable"-> "vulnerable"
x86/cpuid: Fix up "virtual" IBRS/IBPB/STIBP feature bits on Intel
x86/paravirt: Remove 'noreplace-paravirt' cmdline option
x86/kvm: Update spectre-v1 mitigation
x86/retpoline: Avoid retpolines for built-in __init functions
x86/spectre: Simplify spectre_v2 command line parsing
x86/pti: Mark constant arrays as __initconst
x86/speculation: Fix typo IBRS_ATT, which should be IBRS_ALL
KVM: nVMX: kmap() can't fail
KVM: nVMX: vmx_complete_nested_posted_interrupt() can't fail
KVM: nVMX: mark vmcs12 pages dirty on L2 exit
KVM: nVMX: Eliminate vmcs02 pool
KVM: VMX: introduce alloc_loaded_vmcs
KVM: VMX: make MSR bitmaps per-VCPU
KVM/x86: Add IBPB support
KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES
KVM/VMX: Allow direct access to MSR_IA32_SPEC_CTRL
KVM/SVM: Allow direct access to MSR_IA32_SPEC_CTRL
crypto: tcrypt - fix S/G table for test_aead_speed()
ASoC: simple-card: Fix misleading error message
ASoC: rsnd: don't call free_irq() on Parent SSI
ASoC: rsnd: avoid duplicate free_irq()
drm: rcar-du: Use the VBK interrupt for vblank events
drm: rcar-du: Fix race condition when disabling planes at CRTC stop
x86/microcode: Do the family check first
Linux 4.9.81
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
(cherry picked from commit caf7501a1b)
There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.
To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.
If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.
[ tglx: Massaged changelog ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changes in 4.9.77
dm bufio: fix shrinker scans when (nr_to_scan < retain_target)
mac80211: Add RX flag to indicate ICV stripped
ath10k: rebuild crypto header in rx data frames
KVM: Fix stack-out-of-bounds read in write_mmio
can: gs_usb: fix return value of the "set_bittiming" callback
IB/srpt: Disable RDMA access by the initiator
MIPS: Validate PR_SET_FP_MODE prctl(2) requests against the ABI of the task
MIPS: Factor out NT_PRFPREG regset access helpers
MIPS: Guard against any partial write attempt with PTRACE_SETREGSET
MIPS: Consistently handle buffer counter with PTRACE_SETREGSET
MIPS: Fix an FCSR access API regression with NT_PRFPREG and MSA
MIPS: Also verify sizeof `elf_fpreg_t' with PTRACE_SETREGSET
MIPS: Disallow outsized PTRACE_SETREGSET NT_PRFPREG regset accesses
kvm: vmx: Scrub hardware GPRs at VM-exit
platform/x86: wmi: Call acpi_wmi_init() later
x86/acpi: Handle SCI interrupts above legacy space gracefully
ALSA: pcm: Remove incorrect snd_BUG_ON() usages
ALSA: pcm: Add missing error checks in OSS emulation plugin builder
ALSA: pcm: Abort properly at pending signal in OSS read/write loops
ALSA: pcm: Allow aborting mutex lock at OSS read/write loops
ALSA: aloop: Release cable upon open error path
ALSA: aloop: Fix inconsistent format due to incomplete rule
ALSA: aloop: Fix racy hw constraints adjustment
x86/acpi: Reduce code duplication in mp_override_legacy_irq()
zswap: don't param_set_charp while holding spinlock
lan78xx: use skb_cow_head() to deal with cloned skbs
sr9700: use skb_cow_head() to deal with cloned skbs
smsc75xx: use skb_cow_head() to deal with cloned skbs
cx82310_eth: use skb_cow_head() to deal with cloned skbs
xhci: Fix ring leak in failure path of xhci_alloc_virt_device()
8021q: fix a memory leak for VLAN 0 device
ip6_tunnel: disable dst caching if tunnel is dual-stack
net: core: fix module type in sock_diag_bind
RDS: Heap OOB write in rds_message_alloc_sgs()
RDS: null pointer dereference in rds_atomic_free_op
sh_eth: fix TSU resource handling
sh_eth: fix SH7757 GEther initialization
net: stmmac: enable EEE in MII, GMII or RGMII only
ipv6: fix possible mem leaks in ipv6_make_skb()
ethtool: do not print warning for applications using legacy API
mlxsw: spectrum_router: Fix NULL pointer deref
net/sched: Fix update of lastuse in act modules implementing stats_update
crypto: algapi - fix NULL dereference in crypto_remove_spawns()
rbd: set max_segments to USHRT_MAX
x86/microcode/intel: Extend BDW late-loading with a revision check
KVM: x86: Add memory barrier on vmcs field lookup
drm/vmwgfx: Potential off by one in vmw_view_add()
kaiser: Set _PAGE_NX only if supported
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
bpf: move fixup_bpf_calls() function
bpf: refactor fixup_bpf_calls()
bpf: prevent out-of-bounds speculation
bpf, array: fix overflow in max_entries and undefined behavior in index_mask
USB: serial: cp210x: add IDs for LifeScan OneTouch Verio IQ
USB: serial: cp210x: add new device ID ELV ALC 8xxx
usb: misc: usb3503: make sure reset is low for at least 100us
USB: fix usbmon BUG trigger
usbip: remove kernel addresses from usb device and urb debug msgs
usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input
usbip: vudc_tx: fix v_send_ret_submit() vulnerability to null xfer buffer
staging: android: ashmem: fix a race condition in ASHMEM_SET_SIZE ioctl
Bluetooth: Prevent stack info leak from the EFS element.
uas: ignore UAS for Norelsys NS1068(X) chips
e1000e: Fix e1000_check_for_copper_link_ich8lan return value.
x86/Documentation: Add PTI description
x86/cpu: Factor out application of forced CPU caps
x86/cpufeatures: Make CPU bugs sticky
x86/cpufeatures: Add X86_BUG_CPU_INSECURE
x86/pti: Rename BUG_CPU_INSECURE to BUG_CPU_MELTDOWN
x86/cpufeatures: Add X86_BUG_SPECTRE_V[12]
x86/cpu: Merge bugs.c and bugs_64.c
sysfs/cpu: Add vulnerability folder
x86/cpu: Implement CPU vulnerabilites sysfs functions
x86/cpu/AMD: Make LFENCE a serializing instruction
x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC
sysfs/cpu: Fix typos in vulnerability documentation
x86/alternatives: Fix optimize_nops() checking
x86/alternatives: Add missing '\n' at end of ALTERNATIVE inline asm
x86/mm/32: Move setup_clear_cpu_cap(X86_FEATURE_PCID) earlier
objtool, modules: Discard objtool annotation sections for modules
objtool: Detect jumps to retpoline thunks
objtool: Allow alternatives to be ignored
x86/asm: Use register variable to get stack pointer value
x86/retpoline: Add initial retpoline support
x86/spectre: Add boot time option to select Spectre v2 mitigation
x86/retpoline/crypto: Convert crypto assembler indirect jumps
x86/retpoline/entry: Convert entry assembler indirect jumps
x86/retpoline/ftrace: Convert ftrace assembler indirect jumps
x86/retpoline/hyperv: Convert assembler indirect jumps
x86/retpoline/xen: Convert Xen hypercall indirect jumps
x86/retpoline/checksum32: Convert assembler indirect jumps
x86/retpoline/irq32: Convert assembler indirect jumps
x86/retpoline: Fill return stack buffer on vmexit
selftests/x86: Add test_vsyscall
x86/retpoline: Remove compile time warning
objtool: Fix retpoline support for pre-ORC objtool
x86/pti/efi: broken conversion from efi to kernel page table
Linux 4.9.77
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit e390f9a968 upstream.
The '__unreachable' and '__func_stack_frame_non_standard' sections are
only used at compile time. They're discarded for vmlinux but they
should also be discarded for modules.
Since this is a recurring pattern, prefix the section names with
".discard.". It's a nice convention and vmlinux.lds.h already discards
such sections.
Also remove the 'a' (allocatable) flag from the __unreachable section
since it doesn't make sense for a discarded section.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: d1091c7fa3 ("objtool: Improve detection of BUG() and other dead ends")
Link: http://lkml.kernel.org/r/20170301180444.lhd53c5tibc4ns77@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[dwmw2: Remove the unreachable part in backporting since it's not here yet]
Signed-off-by: David Woodhouse <dwmw@amazon.co.ku>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Largely redundant code is used in different places to generate C headers
from offset information extracted from assembly language output.
Consolidate the code in Makefile.lib and use this instead.
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
(cherry picked from commit ebf003f0cf)
Move the definition of fsl_mc_device_id to its proper location in
mod_devicetable.h, and add fsl-mc bus support to devicetable-offsets.c
and file2alias.c to enable device table matching. With this patch udev
based module loading of fsl-mc drivers is supported.
Signed-off-by: Stuart Yoder <stuart.yoder@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because of an improper dereference, a stray 'C' character was output to
the modalias when no 'compatible' was specified. This is the case for
some old PowerMac drivers which only set the 'name' property. Fix it to
let them match again.
Reported-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: Mathieu Malaterre <malat@debian.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Fixes: 6543becf26 ("mod/file2alias: make modalias generation safe for cross compiling")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Since the wildcard at the end of OF module aliases is gone, autoloading
of modules that don't match a device's last (most generic) compatible
value fails.
For example the CODA960 VPU on i.MX6Q has the SoC specific compatible
"fsl,imx6q-vpu" and the generic compatible "cnm,coda960". Since the
driver currently only works with knowledge about the SoC specific
integration, it doesn't list "cnm,cod960" in the module device table.
This results in the device compatible
"of:NvpuT<NULL>Cfsl,imx6q-vpuCcnm,coda960" not matching the module alias
"of:N*T*Cfsl,imx6q-vpu" anymore, whereas before commit 2f632369ab
("modpost: don't add a trailing wildcard for OF module aliases") it
matched the module alias "of:N*T*Cfsl,imx6q-vpu*".
This patch adds two module aliases for each compatible, one without the
wildcard and one with "C*" appended.
$ modinfo coda | grep imx6q
alias: of:N*T*Cfsl,imx6q-vpuC*
alias: of:N*T*Cfsl,imx6q-vpu
Fixes: 2f632369ab ("modpost: don't add a trailing wildcard for OF module aliases")
Link: http://lkml.kernel.org/r/1462203339-15340-1-git-send-email-p.zabel@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Javier Martinez Canillas <javier@osg.samsung.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org> [4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Code which runs outside the kernel's normal mode of operation often does
unusual things which can cause a static analysis tool like objtool to
emit false positive warnings:
- boot image
- vdso image
- relocation
- realmode
- efi
- head
- purgatory
- modpost
Set OBJECT_FILES_NON_STANDARD for their related files and directories,
which will tell objtool to skip checking them. It's ok to skip them
because they don't affect runtime stack traces.
Also skip the following code which does the right thing with respect to
frame pointers, but is too "special" to be validated by a tool:
- entry
- mcount
Also skip the test_nx module because it modifies its exception handling
table at runtime, which objtool can't understand. Fortunately it's
just a test module so it doesn't matter much.
Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but it
might eventually be useful for other tools.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
PowerPC64 uses the symbol .TOC. much as other targets use
_GLOBAL_OFFSET_TABLE_. It identifies the value of the GOT pointer (or in
powerpc parlance, the TOC pointer). Global offset tables are generally
local to an executable or shared library, or in the kernel, module. Thus
it does not make sense for a module to resolve a relocation against
.TOC. to the kernel's .TOC. value. A module has its own .TOC., and
indeed the powerpc64 module relocation processing ignores the kernel
value of .TOC. and instead calculates a module-local value.
This patch removes code involved in exporting the kernel .TOC., tweaks
modpost to ignore an undefined .TOC., and the module loader to twiddle
the section symbol so that .TOC. isn't seen as undefined.
Note that if the kernel was compiled with -msingle-pic-base then ELFv2
would not have function global entry code setting up r2. In that case
the module call stubs would need to be modified to set up r2 using the
kernel .TOC. value, requiring some of this code to be reinstated.
mpe: Furthermore a change in binutils master (not yet released) causes
the current way we handle the TOC to no longer work when building with
MODVERSIONS=y and RELOCATABLE=n. The symptom is that modules can not be
loaded due to there being no version found for TOC.
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: Alan Modra <amodra@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit ac55182899 ("modpost: i2c aliases need no trailing wildcard")
removed the wildcard at the end of the I2C module aliases because I2C
devices have no IDs so the aliases are just arbitrary device names.
This is also true for OF modaliases since a compatible string is used to
define a specific IP hardware block. So the modalias should match a
specific compatible string and not attempt to match a compatible string
whose name matches the beginning of another one.
For example, the following driver module:
$ modinfo cros_ec_keyb | grep alias
alias: platform:cros-ec-keyb
alias: of:N*T*Cgoogle,cros-ec-keyb*
will be tried to be loaded for an alias of:N*T*Cgoogle,cros-ec-keyb-v2
but there could be a different driver that supports the device for that
compatible string so it's better to remove the trailing wildcard for OF.
Also, remove the word "always" from the add_wildcard() function comment
since that was carried from the time where a wildcard was always added
at the end of the module alias for all the devices.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Suggested-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Consistently use uuid_le type in the Hyper-V driver code.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull module updates from Rusty Russell:
"Nothing exciting, minor tweaks and cleanups"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
scripts: [modpost] add new sections to white list
modpost: Add flag -E for making section mismatches fatal
params: don't ignore the rest of cmdline if parse_one() fails
modpost: abort if a module symbol is too long
Pull sound updates from Takashi Iwai:
"Here is the first batch of updates for sound system on 4.4-rc1.
Again at this time, the update looks fairly calm; no big changes in
either ALSA core or ASoC infrastructures, rather all small cleanups,
in addition to the new stuff as usual.
The biggest changes are about Firewire sound devices. It gained lots
of new device support, and MIDI functionality. Also there are updates
for a few still working-in-progress stuff (topology API and ASoC
skylake), too. But overall, this update should give no big surprise.
Some highlights are below:
Core:
- A few more Kconfig items for tinification; it's marked as EXPERT,
so normal user should't be bothered :)
- Refactoring with a new PCM hw_constraint helper
- Removal of unused transfer_ack_{begin,end} PCM callbacks
Firewire:
- Restructuring of code subtree, lots of refactoring
- Support AMDTP variants
- New driver for Digidesign 002/003 family
- Adds support for TASCAM FireOne to ALSA OXFW driver
- Add MIDI support to TASCAM and Digi00x devices
HD-Audio:
- Automated modalias generation for codec drivers, finally
- Improvement on heuristics for setting mixer name
- A few fixes for longstanding bugs on Creative CA0132 cards
- Addition of audio rate callback with i915 communication
- Fix suspend issue on recent Dell XPS
- Intel Lewisburg controller support
ASoC:
- Updates to the topology userspace interface
- Big updates to the Renesas support (rcar)
- More updates for supporting Intel Sky Lake systems
- New drivers for Asahi Kasei Microdevices AK4613, Allwinnner A10,
Cirrus Logic WM8998, Dialog DA7219, Nuvoton NAU8825, Rockchip
S/PDIF, and Atmel class D amplifier
USB-Audio:
- A fix for newer Roland MIDI devices
- Quirks and workarounds for Zoom R16/24 device
Misc:
- A few fixes for some old Cirrus CS46xx PCI sound boards
- Yet another fixes for some old ESS Maestro3 PCI sound boards"
* tag 'sound-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (330 commits)
ALSA: hda - Add Intel Lewisburg device IDs Audio
ALSA: hda - Apply pin fixup for HP ProBook 6550b
ALSA: hda - Fix lost 4k BDL boundary workaround
ALSA: maestro3: Fix Allegro mute until master volume/mute is touched
ALSA: maestro3: Enable docking support for Dell Latitude C810
ALSA: firewire-digi00x: add another rawmidi character device for MIDI control ports
ALSA: firewire-digi00x: add MIDI operations for MIDI control port
ALSA: firewire-digi00x: rename identifiers of MIDI operation for physical ports
ALSA: cs46xx: Fix suspend for all channels
ALSA: cs46xx: Fix Duplicate front for CS4294 and CS4298 codecs
ALSA: DocBook: Add soc-ops.c and soc-compress.c
ALSA: hda - Add / fix kernel doc comments
ALSA: Constify ratden/ratnum constraints
ALSA: hda - Disable 64bit address for Creative HDA controllers
ALSA: hda/realtek - Dell XPS one ALC3260 speaker no sound after resume back
ALSA: hda/ca0132 - Convert leftover pr_info() and pr_err()
ASoC: fsl: Use #ifdef instead of #if for CONFIG_PM_SLEEP
ASoC: rt5645: Sort the order for register bit defines
ASoC: dwc: add check for master/slave format
ASoC: rt5645: Add the HWEQ for the speaker output
...
In our ARC toolchain the default linker script includes special
sections used for code and data located in special fast memory.
To avoid warnings we add these sections i.e. .cmem* and .fmt_slot*
to white list.
Signed-off-by: Noam Camus <noamc@ezchip.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
For generating modalias entries automatically, move the definition of
struct hda_device_id to linux/mod_devicetable.h and add the handling
of this record in file2alias helper. The new modalias is represented
with combination of vendor id, device id, and api version as
"hdaudio:vNrNaN".
This patch itself doesn't convert the existing modaliases. Since they
were added manually, this patch won't give any regression by itself at
this point.
[Modified the modalias format to adapt the api_version field, and drop
invalid ANY_ID definition by tiwai]
Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Reviewed-by: Vinod Koul <vinod.koul@intel.com>
Tested-by: Subhransu S Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The section mismatch warning can be easy to miss during the kernel build
process. Allow it to be marked as fatal to be easily caught and prevent
bugs from slipping in.
Setting CONFIG_SECTION_MISMATCH_WARN_ONLY=y causes these warnings to be
non-fatal, since there are a number of section mismatches when using
allmodconfig on some architectures, and we do not want to break these
builds by default.
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Change-Id: Ic346706e3297c9f0d790e3552aa94e5cff9897a6
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The device alias now looks like mei:S:uuid:N:*
In that way we can bind different drivers to clients with
different protocol versions if required.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
scripts/mod/file2alias.c:add_uuid() convert UUID into a single string
which does not conform to the standard little endian UUID formatting.
This patch changes add_uuid() to output same format as %pUL and modifies
the mei driver to match the change.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Certain platforms (e. g. BSD-based ones) define some ELF constants
according to host. This patch fixes problems with cross-building
Linux kernel on these platforms (e. g. building ARM 32-bit version
on x86-64 host).
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
Module symbols have a limited length, but currently the build system
allows the build finishing even if the driver code contains a too long
symbol name, which eventually overflows the modversion_info[] item.
The compiler may catch at compiling *.mod.c like
CC xxx.mod.o
xxx.mod.c:18:16: warning: initializer-string for array of chars is too long
but it's merely a warning.
This patch adds the check of the symbol length in modpost and stops
the build properly.
Currently MODULE_NAME_LEN is defined in modpost.c instead of referring
to the definition in kernel header because including linux/module.h is
messy and we must cover cross-compilation.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Pull power management and ACPI updates from Rafael Wysocki:
"These are fixes on top of the previous PM+ACPI pull requests
(including one fix for a 4.1 regression) and two commits adding
_CLS-based device enumeration support to the ACPI core and the ATA
subsystem that waited for the latest ACPICA changes to be merged.
Specifics:
- Fix for an ACPI resources management regression introduced during
the 4.1 cycle (that unfortunately went into -stable) effectively
reverting the bad commit along with the recent fixups on top of it
and using an alternative approach to address the underlying issue
(Rafael J Wysocki).
- Fix for a memory leak and an incorrect return value in an error
code path in the ACPI LPSS (Low-Power Subsystem) driver (Rafael J
Wysocki).
- Fix for a leftover dangling pointer in an error code path in the
new wakeup IRQ support code (Rafael J Wysocki).
- Fix to prevent infinite loops (due to errors in other places) from
happening in the core generic PM domains support code (Geert
Uytterhoeven).
- Hibernation documentation update/clarification (Uwe Geuder).
- Support for _CLS-based device enumeration in the ACPI core and in
the ATA subsystem (Suravee Suthikulpanit)"
* tag 'pm+acpi-4.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / wakeirq: Avoid setting power.wakeirq too hastily
ata: ahci_platform: Add ACPI _CLS matching
ACPI / scan: Add support for ACPI _CLS device matching
PM / hibernate: clarify resume documentation
PM / Domains: Avoid infinite loops in attach/detach code
ACPI / LPSS: Fix up acpi_lpss_create_device()
ACPI / PNP: Reserve ACPI resources at the fs_initcall_sync stage
The tilegx and tilepro compilers use .coldtext for their unlikely
executed text section name, so an __attribute__((cold)) function
will (when compiled with higher optimization levels) land in
the .coldtext section.
Modify modpost to add .coldtext to the set of OTHER_TEXT_SECTIONS
so we don't get warnings about referencing such a section in an
__ex_table block, and then also modify arch/tile/lib/memcpy_user_64.c
so that it uses plain ".coldtext" instead of ".coldtext.memcpy".
The latter naming is a relic of an earlier use of -ffunction-sections,
which we no longer use by default.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Device drivers typically use ACPI _HIDs/_CIDs listed in struct device_driver
acpi_match_table to match devices. However, for generic drivers, we do not
want to list _HID for all supported devices. Also, certain classes of devices
do not have _CID (e.g. SATA, USB). Instead, we can leverage ACPI _CLS,
which specifies PCI-defined class code (i.e. base-class, subclass and
programming interface). This patch adds support for matching ACPI devices using
the _CLS method.
To support loadable module, current design uses _HID or _CID to match device's
modalias. With the new way of matching with _CLS this would requires modification
to the current ACPI modalias key to include _CLS. This patch appends PCI-defined
class-code to the existing ACPI modalias as following.
acpi:<HID>:<CID1>:<CID2>:..:<CIDn>:<bbsspp>:
E.g:
# cat /sys/devices/platform/AMDI0600:00/modalias
acpi:AMDI0600:010601:
where bb is th base-class code, ss is te sub-class code, and pp is the
programming interface code
Since there would not be _HID/_CID in the ACPI matching table of the driver,
this patch adds a field to acpi_device_id to specify the matching _CLS.
static const struct acpi_device_id ahci_acpi_match[] = {
{ ACPI_DEVICE_CLASS(PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff) },
{},
};
In this case, the corresponded entry in modules.alias file would be:
alias acpi*:010601:* ahci_platform
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull USB updates from Greg KH:
"Here's the big USB patchset for 4.2-rc1. As is normal these days, the
majority of changes are in the gadget drivers, with a bunch of other
small driver changes.
All of these have been in linux-next with no reported issues"
* tag 'usb-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (175 commits)
usb: dwc3: Use ASCII space in Kconfig
usb: chipidea: add work-around for Marvell HSIC PHY startup
usb: chipidea: allow multiple instances to use default ci_default_pdata
dt-bindings: Consolidate ChipIdea USB ci13xxx bindings
phy: add Marvell HSIC 28nm PHY
phy: Add Marvell USB 2.0 OTG 28nm PHY
dt-bindings: Add Marvell PXA1928 USB and HSIC PHY bindings
USB: ssb: use devm_kzalloc
USB: ssb: fix error handling in ssb_hcd_create_pdev()
usb: isp1760: check for null return from kzalloc
cdc-acm: Add support of ATOL FPrint fiscal printers
usb: chipidea: usbmisc_imx: Remove unneeded semicolon
USB: usbtmc: add device quirk for Rigol DS6104
USB: serial: mos7840: Use setup_timer
phy: twl4030-usb: add ABI documentation
phy: twl4030-usb: remove incorrect pm_runtime_get_sync() in probe function.
phy: twl4030-usb: remove pointless 'suspended' test in 'suspend' callback.
phy: twl4030-usb: make runtime pm more reliable.
drivers:usb:fsl: Fix compilation error for fsl ehci drv
usb: renesas_usbhs: Don't disable the pipe if Control write status stage
...
A previous commit, c93b76b34b ("mei: bus: report also uuid in module
alias") caused a build error as I missed applying a needed patch to add
some macros to uapi/linux/uuid.h. Instead of those additional macros,
change the mei code to use the existing uuid structure directly.
Fixes: c93b76b34b
Cc: Tomas Winkler <tomas.winkler@intel.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UTMI+ Low Pin Interface (ULPI) is a commonly used PHY
interface for USB 2.0. The ULPI specification describes a
standard set of registers which the vendors can extend for
their specific needs. ULPI PHYs provide often functions
such as charger detection and ADP sensing and probing.
There are two major issues that the bus type is meant to
tackle:
Firstly, ULPI registers are accessed from the controller.
The bus provides convenient method for the controller
drivers to share that access with the actual PHY drivers.
Secondly, there are already platforms that assume ULPI PHYs
are runtime detected, such as many Intel Baytrail based
platforms. They do not provide any kind of hardware
description for the ULPI PHYs like separate ACPI device
object that could be used to enumerate a device from.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Pull module updates from Rusty Russell:
"Quentin opened a can of worms by adding extable entry checking to
modpost, but most architectures seem fixed now. Thanks to all
involved.
Last minute rebase because I noticed a "[PATCH]" had snuck into a
commit message somehow"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
modpost: don't emit section mismatch warnings for compiler optimizations
modpost: expand pattern matching to support substring matches
modpost: do not try to match the SHT_NUL section.
modpost: fix extable entry size calculation.
modpost: fix inverted logic in is_extable_fault_address().
modpost: handle -ffunction-sections
modpost: Whitelist .text.fixup and .exception.text
params: handle quotes properly for values not of form foo="bar".
modpost: document the use of struct section_check.
modpost: handle relocations mismatch in __ex_table.
scripts: add check_extable.sh script.
modpost: mismatch_handler: retrieve tosym information only when needed.
modpost: factorize symbol pretty print in get_pretty_name().
modpost: add handler function pointer to sectioncheck.
modpost: add .sched.text and .kprobes.text to the TEXT_SECTIONS list.
modpost: add strict white-listing when referencing sections.
module: do not print allocation-fail warning on bogus user buffer size
kernel/module.c: fix typos in message about unused symbols
Currently an allyesconfig build [gcc-4.9.1] can generate the following:
WARNING: vmlinux.o(.text.unlikely+0x3864): Section mismatch in
reference from the function cpumask_empty.constprop.3() to the
variable .init.data:nmi_ipi_mask
which comes from the cpumask_empty usage in arch/x86/kernel/nmi_selftest.c.
Normally we would not see a symbol entry for cpumask_empty since it is:
static inline bool cpumask_empty(const struct cpumask *srcp)
however in this case, the variant of the symbol gets emitted when GCC does
constant propagation optimization.
Fix things up so that any locally optimized constprop variants don't warn
when accessing variables that live in the __init sections.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Currently the match() function supports a leading * to match any
prefix and a trailing * to match any suffix. However there currently
is not a combination of both that can be used to target matches of
whole families of functions that share a common substring.
Here we expand the *foo and foo* match to also support *foo* with
the goal of targeting compiler generated symbol names that contain
strings like ".constprop." and ".isra."
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Trying to match the SHT_NUL section isn't useful and causes build failures
on parisc and mn10300 since the addition of section strict white-listing
and __ex_table sanitizing.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Fixes: 050e57fd59 ("modpost: add strict white-listing when referencing....")
Fixes: 52dc0595d5 ("modpost: handle relocations mismatch in __ex_table.")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
As Guenter pointed out, we were never really calculating the extable entry
size because the pointer arithmetic was simply wrong. We want to check
we're handling the second relocation in __ex_table to infer an entry size,
but we were using (void*) pointers instead of Elf_Rel[a]* ones.
This fixes the problem by moving that check in the caller (since we can
deal with different types of relocations) and add is_second_extable_reloc()
to make the whole thing more readable.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
As Guenter pointed out, we want to assert that extable_entry_size has been
discovered and not the other way around. Moreover, this sanity check is
only valid when we're not dealing with the first relocation in __ex_table,
since we have not discovered the extable entry size at that point.
This was leading to a divide-by-zero on some architectures and make the
build fail.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
52dc0595d5 introduced OTHER_TEXT_SECTIONS for identifying what
sections could validly have __ex_table entries. Unfortunately, it
wasn't tested with -ffunction-sections, which some architectures
use.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
32-bit and 64-bit ARM use these sections to store executable code, so
they must be whitelisted in modpost's table of valid text sections.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
struct section_check is used as a generic way of describing what
relocations are authorized/forbidden when running modpost. This commit
tries to describe how each field is used.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (Fixed "mist"ake)
__ex_table is a simple table section where each entry is a pair of
addresses - the first address is an address which can fault in kernel
space, and the second address points to where the kernel should jump to
when handling that fault. This is how copy_from_user() does not crash the
kernel if userspace gives a borked pointer for example.
If one of these addresses point to a non-executable section, something is
seriously wrong since it either means the kernel will never fault from
there or it will not be able to jump to there. As both cases are serious
enough, we simply error out in these cases so the build fails and the
developper has to fix the issue.
In case the section is executable, but it isn't referenced in our list of
authorized sections to point to from __ex_table, we just dump a warning
giving more information about it. We do this in case the new section is
executable but isn't supposed to be executed by the kernel. This happened
with .altinstr_replacement, which is executable but is only used to copy
instructions from - we should never have our instruction pointer pointing
in .altinstr_replacement. Admitedly, a proper fix in that case would be to
just set .altinstr_replacement NX, but we need to warn about future cases
like this.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (added long casts)
