[RFC PATCH v1 15/19] powerpc/signal32: Switch handle_signal32() to user_access_begin() logic

From: Christophe Leroy
Date: Wed Aug 12 2020 - 08:07:05 EST


Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/kernel/signal_32.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 0d076c2a9f6c..4ea83578ba9d 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -1241,23 +1241,23 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,

/* Set up Signal Frame */
frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
- if (!access_ok(frame, sizeof(*frame)))
+ if (!user_write_access_begin(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;

#if _NSIG != 64
#error "Please adjust handle_signal()"
#endif
- if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
- || __put_user(oldset->sig[0], &sc->oldmask)
+ unsafe_put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler, failed);
+ unsafe_put_user(oldset->sig[0], &sc->oldmask, failed);
#ifdef CONFIG_PPC64
- || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
+ unsafe_put_user((oldset->sig[0] >> 32), &sc->_unused[3], failed);
#else
- || __put_user(oldset->sig[1], &sc->_unused[3])
+ unsafe_put_user(oldset->sig[1], &sc->_unused[3], failed);
#endif
- || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
- || __put_user(ksig->sig, &sc->signal))
- goto badframe;
+ unsafe_put_user(to_user_ptr(&frame->mctx), &sc->regs, failed);
+ unsafe_put_user(ksig->sig, &sc->signal, failed);
+ user_write_access_end();

if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
sigret = 0;
@@ -1300,6 +1300,9 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
regs->msr &= ~MSR_LE;
return 0;

+failed:
+ user_write_access_end();
+
badframe:
signal_fault(tsk, regs, "handle_signal32", frame);

--
2.25.0