generic compat_sys_ustat

Due to a different size of ino_t ustat needs a compat handler, but
currently only x86 and mips provide one.  Add a generic compat_sys_ustat
and switch all architectures over to it.  Instead of doing various
user copy hacks compat_sys_ustat just reimplements sys_ustat as
it's trivial.  This was suggested by Arnd Bergmann.

Found by Eric Sandeen when running xfstests/017 on ppc64, which causes
stack smashing warnings on RHEL/Fedora due to the too large amount of
data writen by the syscall.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Christoph Hellwig
2008-11-28 10:09:09 +01:00
committed by Al Viro
parent ec1ab0abde
commit 2b1c6bd77d
13 changed files with 43 additions and 72 deletions

View File

@@ -356,40 +356,6 @@ SYSCALL_DEFINE1(32_personality, unsigned long, personality)
return ret;
}
/* ustat compatibility */
struct ustat32 {
compat_daddr_t f_tfree;
compat_ino_t f_tinode;
char f_fname[6];
char f_fpack[6];
};
extern asmlinkage long sys_ustat(dev_t dev, struct ustat __user * ubuf);
SYSCALL_DEFINE2(32_ustat, dev_t, dev, struct ustat32 __user *, ubuf32)
{
int err;
struct ustat tmp;
struct ustat32 tmp32;
mm_segment_t old_fs = get_fs();
set_fs(KERNEL_DS);
err = sys_ustat(dev, (struct ustat __user *)&tmp);
set_fs(old_fs);
if (err)
goto out;
memset(&tmp32, 0, sizeof(struct ustat32));
tmp32.f_tfree = tmp.f_tfree;
tmp32.f_tinode = tmp.f_tinode;
err = copy_to_user(ubuf32, &tmp32, sizeof(struct ustat32)) ? -EFAULT : 0;
out:
return err;
}
SYSCALL_DEFINE4(32_sendfile, long, out_fd, long, in_fd,
compat_off_t __user *, offset, s32, count)
{

View File

@@ -253,7 +253,7 @@ EXPORT(sysn32_call_table)
PTR compat_sys_utime /* 6130 */
PTR sys_mknod
PTR sys_32_personality
PTR sys_32_ustat
PTR compat_sys_ustat
PTR compat_sys_statfs
PTR compat_sys_fstatfs /* 6135 */
PTR sys_sysfs

View File

@@ -265,7 +265,7 @@ sys_call_table:
PTR sys_olduname
PTR sys_umask /* 4060 */
PTR sys_chroot
PTR sys_32_ustat
PTR compat_sys_ustat
PTR sys_dup2
PTR sys_getppid
PTR sys_getpgrp /* 4065 */