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)
This will be useful when we want to have special handlers which need to go
through more hops to print useful information to the user.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
sched.text and .kprobes.text should behave exactly like .text with regards
to how we should warn about referencing sections which might get discarded
at runtime.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Prints a warning when a section references a section outside a strict
white-list. This will be useful to print a warning if __ex_table
references a non-executable section.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Add MIPS Common Device Memory Map (CDMM) support in the form of a bus in
the standard Linux device model. Each device attached via CDMM is
discoverable via an 8-bit type identifier and may contain a number of
blocks of memory mapped registers in the CDMM region. IRQs are expected
to be handled separately.
Due to the per-cpu (per-VPE for MT cores) nature of the CDMM devices,
all the driver callbacks take place from workqueues which are run on the
right CPU for the device in question, so that the driver doesn't need to
be as concerned about which CPU it is running on. Callbacks also exist
for when CPUs are taken offline, so that any per-CPU resources used by
the driver can be disabled so they don't get forcefully migrated. CDMM
devices are created as children of the CPU device they are attached to.
Any existing CDMM configuration by the bootloader will be inherited,
however platforms wishing to enable CDMM should implement the weak
mips_cdmm_phys_base() function (see asm/cdmm.h) so that the bus driver
knows where it should put the CDMM region in the physical address space
if the bootloader hasn't already enabled it.
A mips_cdmm_early_probe() function is also provided to allow early boot
or particularly low level code to set up the CDMM region and probe for a
specific device type, for example early console or KGDB IO drivers for
the EJTAG Fast Debug Channel (FDC) CDMM device.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9599/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull arm64 updates from Catalin Marinas:
- eBPF JIT compiler for arm64
- CPU suspend backend for PSCI (firmware interface) with standard idle
states defined in DT (generic idle driver to be merged via a
different tree)
- Support for CONFIG_DEBUG_SET_MODULE_RONX
- Support for unmapped cpu-release-addr (outside kernel linear mapping)
- set_arch_dma_coherent_ops() implemented and bus notifiers removed
- EFI_STUB improvements when base of DRAM is occupied
- Typos in KGDB macros
- Clean-up to (partially) allow kernel building with LLVM
- Other clean-ups (extern keyword, phys_addr_t usage)
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (51 commits)
arm64: Remove unneeded extern keyword
ARM64: make of_device_ids const
arm64: Use phys_addr_t type for physical address
aarch64: filter $x from kallsyms
arm64: Use DMA_ERROR_CODE to denote failed allocation
arm64: Fix typos in KGDB macros
arm64: insn: Add return statements after BUG_ON()
arm64: debug: don't re-enable debug exceptions on return from el1_dbg
Revert "arm64: dmi: Add SMBIOS/DMI support"
arm64: Implement set_arch_dma_coherent_ops() to replace bus notifiers
of: amba: use of_dma_configure for AMBA devices
arm64: dmi: Add SMBIOS/DMI support
arm64: Correct ftrace calls to aarch64_insn_gen_branch_imm()
arm64:mm: initialize max_mapnr using function set_max_mapnr
setup: Move unmask of async interrupts after possible earlycon setup
arm64: LLVMLinux: Fix inline arm64 assembly for use with clang
arm64: pageattr: Correctly adjust unaligned start addresses
net: bpf: arm64: fix module memory leak when JIT image build fails
arm64: add PSCI CPU_SUSPEND based cpu_suspend support
arm64: kernel: introduce cpu_init_idle CPU operation
...
Similar to ARM, AArch64 is generating $x and $d syms... which isn't
terribly helpful when looking at %pF output and the like. Filter those
out in kallsyms, modpost and when looking at module symbols.
Seems simplest since none of these check EM_ARM anyway, to just add it
to the strchr used, rather than trying to make things overly
complicated.
initcall_debug improves:
dmesg_before.txt: initcall $x+0x0/0x154 [sg] returned 0 after 26331 usecs
dmesg_after.txt: initcall init_sg+0x0/0x154 [sg] returned 0 after 15461 usecs
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Avoid the variable length array (vla), just use PATH_MAX instead.
This not only makes this code clang friedly, it also leads to a
code size reduction:
text data bss dec hex filename
51765 2224 12416 66405 10365 scripts/mod/modpost.old
51677 2224 12416 66317 1030d scripts/mod/modpost.new
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Internally used symbols of modpost don't need to be externally visible;
make them static. Also constify the string arrays so they resist in the
r/o section instead of being runtime writable.
Those changes lead to a small size reduction as can be seen below:
text data bss dec hex filename
51381 2640 12416 66437 10385 scripts/mod/modpost.old
51765 2224 12416 66405 10365 scripts/mod/modpost.new
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
For several years, the pattern "foo$" has effectively been treated as
equivalent to "foo" due to a bug in the (misnamed) helper
number_prefix(). This hasn't been observed to cause any problems, so
remove the broken $ functionality and change all foo$ patterns to foo.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The scripts/mod/modpost.c triggers the following warning:
scripts/mod/modpost.c: In function ‘remove_dot’:
scripts/mod/modpost.c:1710:10: warning: ignoring return value of ‘strtoul’, declared with attribute warn_unused_result [-Wunused-result]
The remove_dot function that calls strtoul does not care about the
numeric value of the string that is parsed but only looks for the
end of the numeric sequence. As such, it's equivalent to just skip
over all digits.
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Pull kbuild misc updates from Michal Marek:
"This is the non-critical part of kbuild for v3.16-rc1:
- make deb-pkg can do s390x and arm64
- new patterns in scripts/tags.sh
- scripts/tags.sh skips userspace tools' sources (which sometimes
have copies of kernel structures) and symlinks
- improvements to the objdiff tool
- two new coccinelle patches
- other minor fixes"
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
scripts: objdiff: support directories for the augument of record command
scripts: objdiff: fix a comment
scripts: objdiff: change the extension of disassembly from .o to .dis
scripts: objdiff: improve path flexibility for record command
scripts: objdiff: remove unnecessary code
scripts: objdiff: direct error messages to stderr
scripts: objdiff: get the path to .tmp_objdiff more simply
deb-pkg: Add automatic support for s390x architecture
coccicheck: Add unneeded return variable test
kbuild: Fix a typo in documentation
kbuild: trivial - use tabs for code indent where possible
kbuild: trivial - remove trailing empty lines
coccinelle: Check for missing NULL terminators in of_device_id tables
scripts/tags.sh: ignore symlink'ed source files
scripts/tags.sh: add regular expression replacement pattern for memcg
builddeb: add arm64 in the supported architectures
builddeb: use $OBJCOPY variable instead of objcopy
scripts/tags.sh: ignore code of user space tools
scripts/tags.sh: add pattern for DEFINE_HASHTABLE
.gitignore: ignore Module.symvers in all directories
Pull module updates from Rusty Russell:
"Most of this is cleaning up various driver sysfs permissions so we can
re-add the perm check (we unified the module param and sysfs checks,
but the module ones were stronger so we weakened them temporarily).
Param parsing gets documented, and also "--" now forces args to be
handed to init (and ignored by the kernel).
Module NX/RO protections get tightened: we now set them before calling
parse_args()"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
module: set nx before marking module MODULE_STATE_COMING.
samples/kobject/: avoid world-writable sysfs files.
drivers/hid/hid-picolcd_fb: avoid world-writable sysfs files.
drivers/staging/speakup/: avoid world-writable sysfs files.
drivers/regulator/virtual: avoid world-writable sysfs files.
drivers/scsi/pm8001/pm8001_ctl.c: avoid world-writable sysfs files.
drivers/hid/hid-lg4ff.c: avoid world-writable sysfs files.
drivers/video/fbdev/sm501fb.c: avoid world-writable sysfs files.
drivers/mtd/devices/docg3.c: avoid world-writable sysfs files.
speakup: fix incorrect perms on speakup_acntsa.c
cpumask.h: silence warning with -Wsign-compare
Documentation: Update kernel-parameters.tx
param: hand arguments after -- straight to init
modpost: Fix resource leak in read_dump()
Pull trivial tree changes from Jiri Kosina:
"Usual pile of patches from trivial tree that make the world go round"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
staging: go7007: remove reference to CONFIG_KMOD
aic7xxx: Remove obsolete preprocessor define
of: dma: doc fixes
doc: fix incorrect formula to calculate CommitLimit value
doc: Note need of bc in the kernel build from 3.10 onwards
mm: Fix printk typo in dmapool.c
modpost: Fix comment typo "Modules.symvers"
Kconfig.debug: Grammar s/addition/additional/
wimax: Spelling s/than/that/, wording s/destinatary/recipient/
aic7xxx: Spelling s/termnation/termination/
arm64: mm: Remove superfluous "the" in comment
of: Spelling s/anonymouns/anonymous/
dma: imx-sdma: Spelling s/determnine/determine/
ath10k: Improve grammar in comments
ath6kl: Spelling s/determnine/determine/
of: Improve grammar for of_alias_get_id() documentation
drm/exynos: Spelling s/contro/control/
radio-bcm2048.c: fix wrong overflow check
doc: printk-formats: do not mention casts for u64/s64
doc: spelling error changes
...
Function read_dump() memory maps the input via grab_file(), but fails to call
the corresponding unmap function. Add the missing call to release_file().
Detected by Coverity: CID 1192419
Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Pull module updates from Rusty Russell:
"Nothing major: the stricter permissions checking for sysfs broke a
staging driver; fix included. Greg KH said he'd take the patch but
hadn't as the merge window opened, so it's included here to avoid
breaking build"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
staging: fix up speakup kobject mode
Use 'E' instead of 'X' for unsigned module taint flag.
VERIFY_OCTAL_PERMISSIONS: stricter checking for sysfs perms.
kallsyms: fix percpu vars on x86-64 with relocation.
kallsyms: generalize address range checking
module: LLVMLinux: Remove unused function warning from __param_check macro
Fix: module signature vs tracepoints: add new TAINT_UNSIGNED_MODULE
module: remove MODULE_GENERIC_TABLE
module: allow multiple calls to MODULE_DEVICE_TABLE() per module
module: use pr_cont