From 362471b3192e4184fff5fedee1ea20bdf637a0c8 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 19 Mar 2021 11:06:55 +0000 Subject: [PATCH] powerpc/signal32: Perform access_ok() inside restore_user_regs() In preparation of using user_access_begin/end in restore_user_regs(), move the access_ok() inside the function. It makes no difference as the behaviour on a failed access_ok() is the same as on failed restore_user_regs(). Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/c106eb2f37c3040f1fd38b40e50c670feb7cb835.1616151715.git.christophe.leroy@csgroup.eu --- arch/powerpc/kernel/signal_32.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index 8dfe4fe77706..e2b1d2a0abad 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -492,6 +492,8 @@ static long restore_user_regs(struct pt_regs *regs, int i; #endif + if (!access_ok(sr, sizeof(*sr))) + return 1; /* * restore general registers but not including MSR or SOFTE. Also * take care of keeping r2 (TLS) intact if not a signal @@ -963,13 +965,10 @@ static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int if (__get_user(cmcp, &ucp->uc_regs)) return -EFAULT; mcp = (struct mcontext __user *)(u64)cmcp; - /* no need to check access_ok(mcp), since mcp < 4GB */ } #else if (__get_user(mcp, &ucp->uc_regs)) return -EFAULT; - if (!access_ok(mcp, sizeof(*mcp))) - return -EFAULT; #endif set_current_blocked(&set); if (restore_user_regs(regs, mcp, sig)) @@ -1362,8 +1361,7 @@ SYSCALL_DEFINE0(sigreturn) } else { sr = (struct mcontext __user *)from_user_ptr(sigctx.regs); addr = sr; - if (!access_ok(sr, sizeof(*sr)) - || restore_user_regs(regs, sr, 1)) + if (restore_user_regs(regs, sr, 1)) goto badframe; } -- 2.11.0