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| author | Daniel Axtens <dja@axtens.net> | 2020-05-29 16:14:46 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-05-29 21:12:09 +1000 |
| commit | 2f26ed1764b42a8c40d9c48441c73a70d805decf (patch) | |
| tree | 651ec504650d1d9417a10cff6f3393aecabc8903 /arch | |
| parent | 595d153dd1022392083ac93a1550382cbee127e0 (diff) | |
| download | linux-2f26ed1764b42a8c40d9c48441c73a70d805decf.tar.bz2 | |
powerpc/64s: Disable sanitisers for C syscall/interrupt entry/exit code
syzkaller is picking up a bunch of crashes that look like this:
Unrecoverable exception 380 at c00000000037ed60 (msr=8000000000001031)
Oops: Unrecoverable exception, sig: 6 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
Modules linked in:
CPU: 0 PID: 874 Comm: syz-executor.0 Not tainted 5.7.0-rc7-syzkaller-00016-gb0c3ba31be3e #0
NIP: c00000000037ed60 LR: c00000000004bac8 CTR: c000000000030990
REGS: c0000000555a7230 TRAP: 0380 Not tainted (5.7.0-rc7-syzkaller-00016-gb0c3ba31be3e)
MSR: 8000000000001031 <SF,ME,IR,DR,LE> CR: 48222882 XER: 20000000
CFAR: c00000000004bac4 IRQMASK: 0
GPR00: c00000000004bb68 c0000000555a74c0 c0000000024b3500 0000000000000005
GPR04: 0000000000000000 0000000000000000 c00000000004bb88 c008000000910000
GPR08: 00000000000b0000 c00000000004bac8 0000000000016000 c000000002503500
GPR12: c000000000030990 c000000003190000 00000000106a5898 00000000106a0000
GPR16: 00000000106a5890 c000000007a92000 c000000008180e00 c000000007a8f700
GPR20: c000000007a904b0 0000000010110000 c00000000259d318 5deadbeef0000100
GPR24: 5deadbeef0000122 c000000078422700 c000000009ee88b8 c000000078422778
GPR28: 0000000000000001 800000000280b033 0000000000000000 c0000000555a75a0
NIP [c00000000037ed60] __sanitizer_cov_trace_pc+0x40/0x50
LR [c00000000004bac8] interrupt_exit_kernel_prepare+0x118/0x310
Call Trace:
[c0000000555a74c0] [c00000000004bb68] interrupt_exit_kernel_prepare+0x1b8/0x310 (unreliable)
[c0000000555a7530] [c00000000000f9a8] interrupt_return+0x118/0x1c0
--- interrupt: 900 at __sanitizer_cov_trace_pc+0x0/0x50
...<random previous call chain>...
This is caused by __sanitizer_cov_trace_pc() causing an SLB fault
after MSR[RI] has been cleared by __hard_EE_RI_disable(), which we
can not recover from.
Do not instrument the new syscall/interrupt entry/exit code with KCOV,
GCOV or UBSAN.
Reported-by: syzbot-ppc64 <ozlabsyz@au1.ibm.com>
Fixes: 68b34588e202 ("powerpc/64/sycall: Implement syscall entry/exit logic in C")
Signed-off-by: Daniel Axtens <dja@axtens.net>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/Makefile | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 1c4385852d3d..244542ae2a91 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -162,6 +162,9 @@ UBSAN_SANITIZE_kprobes.o := n GCOV_PROFILE_kprobes-ftrace.o := n KCOV_INSTRUMENT_kprobes-ftrace.o := n UBSAN_SANITIZE_kprobes-ftrace.o := n +GCOV_PROFILE_syscall_64.o := n +KCOV_INSTRUMENT_syscall_64.o := n +UBSAN_SANITIZE_syscall_64.o := n UBSAN_SANITIZE_vdso.o := n # Necessary for booting with kcov enabled on book3e machines |