Commit f454322e authored by Dmitry V. Levin's avatar Dmitry V. Levin Committed by Al Viro
Browse files

signal: replace sigset_to_compat() with put_compat_sigset() 



There are 4 callers of sigset_to_compat() in the entire kernel.  One is
in sparc compat rt_sigaction(2), the rest are in kernel/signal.c itself.
All are followed by copy_to_user(), and all but the sparc one are under
"if it's big-endian..." ifdefs.

Let's transform sigset_to_compat() into put_compat_sigset() that also
calls copy_to_user().

Suggested-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarDmitry V. Levin <ldv@altlinux.org>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 2bd6bf03

arch/sparc/kernel/sys_sparc32.c

+3 −3
Original line number Diff line number Diff line
@@ -159,7 +159,6 @@ COMPAT_SYSCALL_DEFINE5(rt_sigaction, int, sig, 
{

        struct k_sigaction new_ka, old_ka;

        int ret;

	compat_sigset_t set32;



        /* XXX: Don't preclude handling different sized sigset_t's.  */

        if (sigsetsize != sizeof(compat_sigset_t))
@@ -167,6 +166,7 @@ COMPAT_SYSCALL_DEFINE5(rt_sigaction, int, sig, 


        if (act) {

		u32 u_handler, u_restorer;

		compat_sigset_t set32;



		new_ka.ka_restorer = restorer;

		ret = get_user(u_handler, &act->sa_handler);
@@ -183,9 +183,9 @@ COMPAT_SYSCALL_DEFINE5(rt_sigaction, int, sig, 
	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);



	if (!ret && oact) {

		sigset_to_compat(&set32, &old_ka.sa.sa_mask);

		ret = put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler);

		ret |= copy_to_user(&oact->sa_mask, &set32, sizeof(compat_sigset_t));

		ret |= put_compat_sigset(&oact->sa_mask, &old_ka.sa.sa_mask,

					 sizeof(oact->sa_mask));

		ret |= put_user(old_ka.sa.sa_flags, &oact->sa_flags);

		ret |= put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer);

		if (ret)

include/linux/compat.h

+2 −1
Original line number Diff line number Diff line
@@ -456,7 +456,8 @@ asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv, 
asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp);



extern void sigset_from_compat(sigset_t *set, const compat_sigset_t *compat);

extern void sigset_to_compat(compat_sigset_t *compat, const sigset_t *set);

extern int put_compat_sigset(compat_sigset_t __user *compat,

			     const sigset_t *set, unsigned int size);



asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,

		compat_ulong_t maxnode, const compat_ulong_t __user *old_nodes,

kernel/compat.c

+14 −6
Original line number Diff line number Diff line
@@ -497,15 +497,23 @@ sigset_from_compat(sigset_t *set, const compat_sigset_t *compat) 
}

EXPORT_SYMBOL_GPL(sigset_from_compat);



void

sigset_to_compat(compat_sigset_t *compat, const sigset_t *set)

int

put_compat_sigset(compat_sigset_t __user *compat, const sigset_t *set,

		  unsigned int size)

{

	/* size <= sizeof(compat_sigset_t) <= sizeof(sigset_t) */

#ifdef __BIG_ENDIAN

	compat_sigset_t v;

	switch (_NSIG_WORDS) {

	case 4: compat->sig[7] = (set->sig[3] >> 32); compat->sig[6] = set->sig[3];

	case 3: compat->sig[5] = (set->sig[2] >> 32); compat->sig[4] = set->sig[2];

	case 2: compat->sig[3] = (set->sig[1] >> 32); compat->sig[2] = set->sig[1];

	case 1: compat->sig[1] = (set->sig[0] >> 32); compat->sig[0] = set->sig[0];

	}

	case 4: v.sig[7] = (set->sig[3] >> 32); v.sig[6] = set->sig[3];

	case 3: v.sig[5] = (set->sig[2] >> 32); v.sig[4] = set->sig[2];

	case 2: v.sig[3] = (set->sig[1] >> 32); v.sig[2] = set->sig[1];

	case 1: v.sig[1] = (set->sig[0] >> 32); v.sig[0] = set->sig[0];

	}

	return copy_to_user(compat, &v, size) ? -EFAULT : 0;

#else

	return copy_to_user(compat, set, size) ? -EFAULT : 0;

#endif

}



#ifdef CONFIG_NUMA

kernel/signal.c

+6 −21
Original line number Diff line number Diff line
@@ -2621,13 +2621,7 @@ COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, 
		if (error)

			return error;

	}

	if (oset) {

		compat_sigset_t old32;

		sigset_to_compat(&old32, &old_set);

		if (copy_to_user(oset, &old32, sizeof(compat_sigset_t)))

			return -EFAULT;

	}

	return 0;

	return oset ? put_compat_sigset(oset, &old_set, sizeof(*oset)) : 0;

#else

	return sys_rt_sigprocmask(how, (sigset_t __user *)nset,

				  (sigset_t __user *)oset, sigsetsize);
@@ -2669,20 +2663,11 @@ SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize) 
COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset,

		compat_size_t, sigsetsize)

{

#ifdef __BIG_ENDIAN

	sigset_t set;

	int err = do_sigpending(&set, sigsetsize);

	if (!err) {

		compat_sigset_t set32;

		sigset_to_compat(&set32, &set);

		/* we can get here only if sigsetsize <= sizeof(set) */

		if (copy_to_user(uset, &set32, sigsetsize))

			err = -EFAULT;

	}

	if (!err)

		err = put_compat_sigset(uset, &set, sigsetsize);

	return err;

#else

	return sys_rt_sigpending((sigset_t __user *)uset, sigsetsize);

#endif

}

#endif
@@ -3451,7 +3436,6 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, 
		compat_size_t, sigsetsize)

{

	struct k_sigaction new_ka, old_ka;

	compat_sigset_t mask;

#ifdef __ARCH_HAS_SA_RESTORER

	compat_uptr_t restorer;

#endif
@@ -3463,6 +3447,7 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, 


	if (act) {

		compat_uptr_t handler;

		compat_sigset_t mask;

		ret = get_user(handler, &act->sa_handler);

		new_ka.sa.sa_handler = compat_ptr(handler);

#ifdef __ARCH_HAS_SA_RESTORER
@@ -3478,10 +3463,10 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, 


	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

	if (!ret && oact) {

		sigset_to_compat(&mask, &old_ka.sa.sa_mask);

		ret = put_user(ptr_to_compat(old_ka.sa.sa_handler), 

			       &oact->sa_handler);

		ret |= copy_to_user(&oact->sa_mask, &mask, sizeof(mask));

		ret |= put_compat_sigset(&oact->sa_mask, &old_ka.sa.sa_mask,

					 sizeof(oact->sa_mask));

		ret |= put_user(old_ka.sa.sa_flags, &oact->sa_flags);

#ifdef __ARCH_HAS_SA_RESTORER

		ret |= put_user(ptr_to_compat(old_ka.sa.sa_restorer),

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