Commit 887f3ceb authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/signal32: Convert do_setcontext[_tm]() to user access block 



Add unsafe_get_user_sigset() and transform PPC32 get_sigset_t()
into an unsafe version unsafe_get_sigset_t().

Then convert do_setcontext() and do_setcontext_tm() to use
user_read_access_begin/end.

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/9273ba664db769b8d9c7540ae91395e346e4945e.1616151715.git.christophe.leroy@csgroup.eu
parent 627b72be

arch/powerpc/kernel/signal.h

+2 −0
Original line number Diff line number Diff line
@@ -25,6 +25,8 @@ static inline int __get_user_sigset(sigset_t *dst, const sigset_t __user *src) 


	return __get_user(dst->sig[0], (u64 __user *)&src->sig[0]);

}

#define unsafe_get_user_sigset(dst, src, label) \

	unsafe_get_user((dst)->sig[0], (u64 __user *)&(src)->sig[0], label)



#ifdef CONFIG_VSX

extern unsigned long copy_vsx_to_user(void __user *to,

arch/powerpc/kernel/signal_32.c

+24 −18
Original line number Diff line number Diff line
@@ -83,12 +83,7 @@ 
 * implementation that makes things simple for little endian only)

 */

#define unsafe_put_sigset_t	unsafe_put_compat_sigset



static inline int get_sigset_t(sigset_t *set,

			       const compat_sigset_t __user *uset)

{

	return get_compat_sigset(set, uset);

}

#define unsafe_get_sigset_t	unsafe_get_compat_sigset



#define to_user_ptr(p)		ptr_to_compat(p)

#define from_user_ptr(p)	compat_ptr(p)
@@ -144,10 +139,7 @@ __unsafe_restore_general_regs(struct pt_regs *regs, struct mcontext __user *sr) 
	unsafe_copy_to_user(__us, __s, sizeof(*__us), label);		\

} while (0)



static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)

{

	return __get_user_sigset(set, uset);

}

#define unsafe_get_sigset_t	unsafe_get_user_sigset



#define to_user_ptr(p)		((unsigned long)(p))

#define from_user_ptr(p)	((void __user *)(p))
@@ -982,25 +974,31 @@ static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int 
	sigset_t set;

	struct mcontext __user *mcp;



	if (get_sigset_t(&set, &ucp->uc_sigmask))

	if (user_read_access_begin(ucp, sizeof(*ucp)))

		return -EFAULT;



	unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);

#ifdef CONFIG_PPC64

	{

		u32 cmcp;



		if (__get_user(cmcp, &ucp->uc_regs))

			return -EFAULT;

		unsafe_get_user(cmcp, &ucp->uc_regs, failed);

		mcp = (struct mcontext __user *)(u64)cmcp;

	}

#else

	if (__get_user(mcp, &ucp->uc_regs))

		return -EFAULT;

	unsafe_get_user(mcp, &ucp->uc_regs, failed);

#endif

	user_read_access_end();



	set_current_blocked(&set);

	if (restore_user_regs(regs, mcp, sig))

		return -EFAULT;



	return 0;



failed:

	user_read_access_end();

	return -EFAULT;

}



#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -1014,11 +1012,15 @@ static int do_setcontext_tm(struct ucontext __user *ucp, 
	u32 cmcp;

	u32 tm_cmcp;



	if (get_sigset_t(&set, &ucp->uc_sigmask))

	if (user_read_access_begin(ucp, sizeof(*ucp)))

		return -EFAULT;



	if (__get_user(cmcp, &ucp->uc_regs) ||

	    __get_user(tm_cmcp, &tm_ucp->uc_regs))

	unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);

	unsafe_get_user(cmcp, &ucp->uc_regs, failed);



	user_read_access_end();



	if (__get_user(tm_cmcp, &tm_ucp->uc_regs))

		return -EFAULT;

	mcp = (struct mcontext __user *)(u64)cmcp;

	tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
@@ -1029,6 +1031,10 @@ static int do_setcontext_tm(struct ucontext __user *ucp, 
		return -EFAULT;



	return 0;



failed:

	user_read_access_end();

	return -EFAULT;

}

#endif