Commit ce10d979 authored by Paul Mackerras's avatar Paul Mackerras Committed by Linus Torvalds
Browse files

[PATCH] ppc64: Fix PER_LINUX32 behaviour 



This patch fixes some bugs in the ppc64 PER_LINUX32 implementation,
noted by Juergen Kreileder:

* uname(2) doesn't respect PER_LINUX32, it returns 'ppc64' instead of 'ppc'
* Child processes of a PER_LINUX32 process don't inherit PER_LINUX32

Along the way I took the opportunity to move things around so that
sys_ppc32.c only has 32-bit syscall emulation functions and to remove
the obsolete "fakeppc" command line option.

Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent fee02f80

arch/ppc64/kernel/misc.S

+1 −1
Original line number Diff line number Diff line
@@ -792,7 +792,7 @@ _GLOBAL(sys_call_table32) 
	.llong .compat_sys_newstat

	.llong .compat_sys_newlstat

	.llong .compat_sys_newfstat

	.llong .sys_uname

	.llong .sys32_uname

	.llong .sys_ni_syscall		/* 110 old iopl syscall */

	.llong .sys_vhangup

	.llong .sys_ni_syscall		/* old idle syscall */

arch/ppc64/kernel/sys_ppc32.c

+33 −37
Original line number Diff line number Diff line
@@ -791,31 +791,6 @@ asmlinkage int sys32_pciconfig_iobase(u32 which, u32 in_bus, u32 in_devfn) 
}





asmlinkage int ppc64_newuname(struct new_utsname __user * name)

{

	int errno = sys_newuname(name);



	if (current->personality == PER_LINUX32 && !errno) {

		if(copy_to_user(name->machine, "ppc\0\0", 8)) {

			errno = -EFAULT;

		}

	}

	return errno;

}



asmlinkage int ppc64_personality(unsigned long personality)

{

	int ret;

	if (current->personality == PER_LINUX32 && personality == PER_LINUX)

		personality = PER_LINUX32;

	ret = sys_personality(personality);

	if (ret == PER_LINUX32)

		ret = PER_LINUX;

	return ret;

}







/* Note: it is necessary to treat mode as an unsigned int,

 * with the corresponding cast to a signed int to insure that the 

 * proper conversion (sign extension) between the register representation of a signed int (msr in 32-bit mode)
@@ -1158,26 +1133,47 @@ asmlinkage long sys32_sysctl(struct __sysctl_args32 __user *args) 
}

#endif



asmlinkage int sys32_uname(struct old_utsname __user * name)

{

	int err = 0;

	

	down_read(&uts_sem);

	if (copy_to_user(name, &system_utsname, sizeof(*name)))

		err = -EFAULT;

	up_read(&uts_sem);

	if (!err && personality(current->personality) == PER_LINUX32) {

		/* change "ppc64" to "ppc" */

		if (__put_user(0, name->machine + 3)

		    || __put_user(0, name->machine + 4))

			err = -EFAULT;

	}

	return err;

}



asmlinkage int sys32_olduname(struct oldold_utsname __user * name)

{

	int error;



	if (!name)

		return -EFAULT;

	if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))

		return -EFAULT;

  

	down_read(&uts_sem);

	error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);

	error -= __put_user(0,name->sysname+__OLD_UTS_LEN);

	error -= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);

	error -= __put_user(0,name->nodename+__OLD_UTS_LEN);

	error -= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);

	error -= __put_user(0,name->release+__OLD_UTS_LEN);

	error -= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);

	error -= __put_user(0,name->version+__OLD_UTS_LEN);

	error -= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);

	error = __put_user(0,name->machine+__OLD_UTS_LEN);

	error |= __put_user(0,name->sysname+__OLD_UTS_LEN);

	error |= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);

	error |= __put_user(0,name->nodename+__OLD_UTS_LEN);

	error |= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);

	error |= __put_user(0,name->release+__OLD_UTS_LEN);

	error |= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);

	error |= __put_user(0,name->version+__OLD_UTS_LEN);

	error |= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);

	error |= __put_user(0,name->machine+__OLD_UTS_LEN);

	if (personality(current->personality) == PER_LINUX32) {

		/* change "ppc64" to "ppc" */

		error |= __put_user(0, name->machine + 3);

		error |= __put_user(0, name->machine + 4);

	}

	

	up_read(&uts_sem);



	error = error ? -EFAULT : 0;

arch/ppc64/kernel/syscalls.c

+21 −12
Original line number Diff line number Diff line
@@ -199,24 +199,33 @@ out: 
	return ret;

}



static int __init set_fakeppc(char *str)

long ppc64_personality(unsigned long personality)

{

	if (*str)

		return 0;

	init_task.personality = PER_LINUX32;

	return 1;

	long ret;



	if (personality(current->personality) == PER_LINUX32

	    && personality == PER_LINUX)

		personality = PER_LINUX32;

	ret = sys_personality(personality);

	if (ret == PER_LINUX32)

		ret = PER_LINUX;

	return ret;

}

__setup("fakeppc", set_fakeppc);



asmlinkage int sys_uname(struct old_utsname __user * name)

long ppc64_newuname(struct new_utsname __user * name)

{

	int err = -EFAULT;

	int err = 0;



	down_read(&uts_sem);

	if (name && !copy_to_user(name, &system_utsname, sizeof (*name)))

		err = 0;

	if (copy_to_user(name, &system_utsname, sizeof(*name)))

		err = -EFAULT;

	up_read(&uts_sem);

	

	if (!err && personality(current->personality) == PER_LINUX32) {

		/* change ppc64 to ppc */

		if (__put_user(0, name->machine + 3)

		    || __put_user(0, name->machine + 4))

			err = -EFAULT;

	}

	return err;

}

include/asm-ppc64/elf.h

+1 −3
Original line number Diff line number Diff line
@@ -221,9 +221,7 @@ do { \ 
		set_thread_flag(TIF_ABI_PENDING);		\

	else							\

		clear_thread_flag(TIF_ABI_PENDING);		\

	if (ibcs2)						\

		set_personality(PER_SVR4);			\

	else if (current->personality != PER_LINUX32)		\

	if (personality(current->personality) != PER_LINUX32)	\

		set_personality(PER_LINUX);			\

} while (0)

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