diff options
| author | Nicholas Piggin | 2020-04-29 16:56:49 +1000 |
|---|---|---|
| committer | Michael Ellerman | 2020-05-04 09:22:58 +1000 |
| commit | c0d7dcf89e5151b2259d1c2c1b922da3b881d02e (patch) | |
| tree | f21569f030498104b3cf1fcdb86f5edf9f6af521 /arch | |
| parent | 0094368e3bb97a710ce163f9c06d290c1c308621 (diff) | |
powerpc/64/kuap: Move kuap checks out of MSR[RI]=0 regions of exit code
Any kind of WARN causes a program check that will crash with
unrecoverable exception if it occurs when RI is clear.
Fixes: 68b34588e202 ("powerpc/64/sycall: Implement syscall entry/exit logic in C")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200429065654.1677541-2-npiggin@gmail.com
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/syscall_64.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c index 1fe94dd9de32..7b7c89cad901 100644 --- a/arch/powerpc/kernel/syscall_64.c +++ b/arch/powerpc/kernel/syscall_64.c @@ -35,6 +35,8 @@ notrace long system_call_exception(long r3, long r4, long r5, BUG_ON(!FULL_REGS(regs)); BUG_ON(regs->softe != IRQS_ENABLED); + kuap_check_amr(); + account_cpu_user_entry(); #ifdef CONFIG_PPC_SPLPAR @@ -47,8 +49,6 @@ notrace long system_call_exception(long r3, long r4, long r5, } #endif - kuap_check_amr(); - /* * This is not required for the syscall exit path, but makes the * stack frame look nicer. If this was initialised in the first stack @@ -117,6 +117,8 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3, unsigned long ti_flags; unsigned long ret = 0; + kuap_check_amr(); + regs->result = r3; /* Check whether the syscall is issued inside a restartable sequence */ @@ -204,8 +206,6 @@ again: local_paca->tm_scratch = regs->msr; #endif - kuap_check_amr(); - account_cpu_user_exit(); return ret; @@ -228,6 +228,8 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned BUG_ON(!FULL_REGS(regs)); BUG_ON(regs->softe != IRQS_ENABLED); + kuap_check_amr(); + local_irq_save(flags); again: @@ -292,8 +294,6 @@ again: local_paca->tm_scratch = regs->msr; #endif - kuap_check_amr(); - account_cpu_user_exit(); return ret; @@ -313,6 +313,8 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign BUG_ON(regs->msr & MSR_PR); BUG_ON(!FULL_REGS(regs)); + kuap_check_amr(); + if (unlikely(*ti_flagsp & _TIF_EMULATE_STACK_STORE)) { clear_bits(_TIF_EMULATE_STACK_STORE, ti_flagsp); ret = 1; |