kernel_optimize_test/arch/mips/kernel
Alexander Lobakin fd416c3f5a MIPS: fix fortify panic when copying asm exception handlers
[ Upstream commit d17b66417308996e7e64b270a3c7f3c1fbd4cfc8 ]

With KCFLAGS="-O3", I was able to trigger a fortify-source
memcpy() overflow panic on set_vi_srs_handler().
Although O3 level is not supported in the mainline, under some
conditions that may've happened with any optimization settings,
it's just a matter of inlining luck. The panic itself is correct,
more precisely, 50/50 false-positive and not at the same time.
From the one side, no real overflow happens. Exception handler
defined in asm just gets copied to some reserved places in the
memory.
But the reason behind is that C code refers to that exception
handler declares it as `char`, i.e. something of 1 byte length.
It's obvious that the asm function itself is way more than 1 byte,
so fortify logics thought we are going to past the symbol declared.
The standard way to refer to asm symbols from C code which is not
supposed to be called from C is to declare them as
`extern const u8[]`. This is fully correct from any point of view,
as any code itself is just a bunch of bytes (including 0 as it is
for syms like _stext/_etext/etc.), and the exact size is not known
at the moment of compilation.
Adjust the type of the except_vec_vi_*() and related variables.
Make set_handler() take `const` as a second argument to avoid
cast-away warnings and give a little more room for optimization.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 21:00:59 +02:00
..
syscalls mm/madvise: introduce process_madvise() syscall: an external memory hinting API 2020-10-18 09:27:10 -07:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
asm-offsets.c MIPS: Remove struct task_struct fpu state when CONFIG_MIPS_FP_SUPPORT=n 2018-11-09 10:23:19 -08:00
binfmt_elfn32.c MIPS: Fix malformed NT_FILE and NT_SIGINFO in 32bit coredumps 2021-01-19 18:27:20 +01:00
binfmt_elfo32.c MIPS: Fix malformed NT_FILE and NT_SIGINFO in 32bit coredumps 2021-01-19 18:27:20 +01:00
bmips_5xxx_init.S MIPS: BCM5xxx: Remove dead init_fpu code 2018-11-08 11:20:57 -08:00
bmips_vec.S
branch.c MIPS: kernel: include probes-common.h header in branch.c 2020-09-21 22:14:24 +02:00
cacheinfo.c drivers: base: cacheinfo: Get rid of DEFINE_SMP_CALL_CACHE_FUNCTION() 2021-09-26 14:08:59 +02:00
cevt-bcm1480.c MIPS: Replace setup_irq() by request_irq() 2020-03-05 16:47:35 +01:00
cevt-ds1287.c MIPS: Replace setup_irq() by request_irq() 2020-03-05 16:47:35 +01:00
cevt-gt641xx.c MIPS: Replace setup_irq() by request_irq() 2020-03-05 16:47:35 +01:00
cevt-r4k.c mips: cevt-r4k: Update the r4k-clockevent frequency in sync with CPU 2020-05-22 09:14:32 +02:00
cevt-sb1250.c MIPS: Replace setup_irq() by request_irq() 2020-03-05 16:47:35 +01:00
cevt-txx9.c MIPS: Replace setup_irq() by request_irq() 2020-03-05 16:47:35 +01:00
cmpxchg.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
cps-vec-ns16550.S mips: Add CPS_NS16550_WIDTH config 2020-05-22 09:12:52 +02:00
cps-vec.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
cpu-probe.c MIPS: loongson64: fix FTLB configuration 2021-12-01 09:19:07 +01:00
cpu-r3k-probe.c MIPS: cpu-probe: introduce exclusive R3k CPU probe 2020-10-12 12:05:16 +02:00
crash_dump.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
crash.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
csrc-bcm1480.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
csrc-ioasic.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
csrc-r4k.c mips: csrc-r4k: Mark R4K timer as unstable if CPU freq changes 2020-05-22 09:14:06 +02:00
csrc-sb1250.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
early_printk_8250.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 1 2019-05-21 11:28:39 +02:00
early_printk.c
elf.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
entry.S mips: Add MIPS Release 5 support 2020-05-22 09:09:01 +02:00
fpu-probe.c MIPS: cpu-probe: move fpu probing/handling into its own file 2020-10-12 12:04:50 +02:00
fpu-probe.h MIPS: cpu-probe: move fpu probing/handling into its own file 2020-10-12 12:04:50 +02:00
ftrace.c MIPS: ftrace: Remove redundant #ifdef CONFIG_DYNAMIC_FTRACE 2020-08-17 13:00:24 +02:00
genex.S MIPS: handle Loongson-specific GSExc exception 2020-07-31 17:52:47 +02:00
gpio_txx9.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
head.S MIPS: Loongson-3: Enable COP2 usage in kernel 2020-09-21 22:15:03 +02:00
i8253.c MIPS: Replace setup_irq() by request_irq() 2020-03-05 16:47:35 +01:00
idle.c sched/idle: Fix arch_cpu_idle() vs tracing 2020-11-24 16:47:35 +01:00
irq_txx9.c
irq-gt641xx.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 1 2019-05-21 11:28:39 +02:00
irq-msc01.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
irq-rm7000.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
irq.c MIPS: irq: Allocate accurate order pages for irq stack 2019-02-19 12:45:01 -08:00
jump_label.c MIPS: jump_label: Use compact branches for >= r6 2019-04-09 16:21:30 -07:00
kgdb.c MIPS: KGDB: fix kgdb support for SMP platforms. 2019-03-28 11:35:58 -07:00
kprobes.c mips: kprobes: Use generic kretprobe trampoline handler 2020-09-08 11:52:33 +02:00
linux32.c MIPS: Delete unused code in linux32.c 2018-08-01 13:20:27 -07:00
machine_kexec.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230 2019-06-19 17:09:06 +02:00
Makefile MIPS: cpu-probe: introduce exclusive R3k CPU probe 2020-10-12 12:05:16 +02:00
mcount.S
mips-cm.c mips: cm: Convert to bitfield API to fix out-of-bounds access 2021-11-18 14:04:21 +01:00
mips-cpc.c remove ioremap_nocache and devm_ioremap_nocache 2020-01-06 09:45:59 +01:00
mips-mt-fpaff.c MIPS: Use rcu to lookup a task in mipsmt_sys_sched_setaffinity() 2020-09-03 10:13:43 +02:00
mips-mt.c MIPS: MT: Remove norps command line parameter 2018-11-26 22:49:14 -08:00
mips-r2-to-r6-emul.c MIPS: Use fallthrough for arch/mips 2020-05-07 11:55:47 +02:00
module.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
octeon_switch.S
perf_event_mipsxx.c MIPS: perf: Fix wrong check condition of Loongson event IDs 2020-09-01 13:52:33 +02:00
perf_event.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
pm-cps.c MIPS: barrier: Add __SYNC() infrastructure 2019-10-07 09:42:17 -07:00
pm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
probes-common.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
proc.c mips: Add MIPS Release 5 support 2020-05-22 09:09:01 +02:00
process.c MIPS: process: include exec.h header in process.c 2020-09-30 21:53:00 +02:00
prom.c MIPS: replace add_memory_region with memblock 2020-10-12 12:01:36 +02:00
ptrace.c mips: switch to ->regset_get() 2020-07-27 14:31:08 -04:00
ptrace32.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
r4k_fpu.S mips: Add MIPS Release 5 support 2020-05-22 09:09:01 +02:00
r4k_switch.S
r4k-bugs64.c MIPS: r4k-bugs64: Drop CONFIG_CPU_MIPSR6 checks 2019-10-07 09:38:54 -07:00
r2300_fpu.S signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT 2021-11-18 14:03:47 +01:00
r2300_switch.S
relocate_kernel.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230 2019-06-19 17:09:06 +02:00
relocate.c MIPS: relocatable: fix possible boot hangup with KASLR enabled 2021-01-19 18:27:20 +01:00
reset.c
rtlx-cmp.c
rtlx-mt.c MIPS: Replace setup_irq() by request_irq() 2020-03-05 16:47:35 +01:00
rtlx.c
scall32-o32.S mips: remove nargs from __SYSCALL 2019-07-30 10:50:30 -07:00
scall64-n32.S mips: remove nargs from __SYSCALL 2019-07-30 10:50:30 -07:00
scall64-n64.S mips: remove nargs from __SYSCALL 2019-07-30 10:50:30 -07:00
scall64-o32.S MIPS: asm: Rename some macros to avoid build errors 2020-05-07 13:20:05 +02:00
segment.c mips: kernel: no need to check return value of debugfs_create functions 2019-01-22 11:17:20 -08:00
setup.c MIPS: Don't round up kernel sections size for memblock_add() 2020-12-30 11:53:34 +01:00
signal_n32.c Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2019-07-08 21:48:15 -07:00
signal_o32.c signal: Remove task parameter from force_sig 2019-05-27 09:36:28 -05:00
signal-common.h
signal.c tracehook: clear TIF_NOTIFY_RESUME in tracehook_notify_resume() 2020-10-17 15:04:36 -06:00
signal32.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
smp-bmips.c MIPS: BMIPS: Also call bmips_cpu_setup() for secondary cores 2020-08-21 09:29:09 +02:00
smp-cmp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 182 2019-05-30 11:29:20 -07:00
smp-cps.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
smp-mt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 182 2019-05-30 11:29:20 -07:00
smp-up.c
smp.c MIPS: smp: fill in sibling and core maps earlier 2022-03-19 13:44:44 +01:00
spinlock_test.c mips: kernel: no need to check return value of debugfs_create functions 2019-01-22 11:17:20 -08:00
spram.c mips: Add CONFIG/CONFIG6/Cause reg fields macro 2020-05-22 09:12:22 +02:00
stacktrace.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
sync-r4k.c MIPS: sync-r4k: do slave counter synchronization with disabled HW interrupts 2020-01-22 10:16:18 -08:00
syscall.c signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT 2021-11-18 14:03:47 +01:00
sysrq.c MIPS: constify sysrq_key_op 2020-05-15 14:53:19 +02:00
time.c mips: Add udelay lpj numbers adjustment 2020-05-22 09:13:32 +02:00
topology.c MIPS: CPU#0 is not hotpluggable 2020-07-26 10:18:35 +02:00
traps.c MIPS: fix fortify panic when copying asm exception handlers 2022-04-13 21:00:59 +02:00
unaligned.c uaccess: add force_uaccess_{begin,end} helpers 2020-08-12 10:57:59 -07:00
uprobes.c MIPS: uprobes: remove set but not used variable 'epc' 2019-05-29 13:20:30 -07:00
vdso.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
vmlinux.lds.S MIPS: properly stop .eh_frame generation 2021-03-04 11:37:41 +01:00
vpe-cmp.c
vpe-mt.c
vpe.c MIPS: VPE: Fix a double free and a memory leak in 'release_vpe()' 2020-02-15 12:44:03 -08:00
watch.c MIPS: Use fallthrough for arch/mips 2020-05-07 11:55:47 +02:00