Commit 362471b3 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

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: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c106eb2f37c3040f1fd38b40e50c670feb7cb835.1616151715.git.christophe.leroy@csgroup.eu
parent ca9e1605

arch/powerpc/kernel/signal_32.c

+3 −5
Original line number Diff line number Diff line
@@ -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;

	}