Commit 962bf131 authored by Arun Sharma's avatar Arun Sharma Committed by Linus Torvalds

[PATCH] sys_getdents64 needs compat wrapper

Due to different structure alignment rules in the ABI between ia32 and
ia64, certain members of the dirent structure are not guaranteed to be 8
byte aligned on ia64.  This requires a compat wrapper around these 32 bit
system calls.  Other architectures may or may not have the problem,
depending on the alignment rules.

This was observed by running /emul/ia32-linux/bin/ls on 2.6.6 which produces
kernel mode unaligned faults.

Original patch by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarGordon Jin <gordon.jin@intel.com>
Signed-off-by: default avatarArun Sharma <arun.sharma@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent ee4a77fc
...@@ -349,7 +349,7 @@ ia32_syscall_table: ...@@ -349,7 +349,7 @@ ia32_syscall_table:
data8 sys_setfsuid /* 16-bit version */ data8 sys_setfsuid /* 16-bit version */
data8 sys_setfsgid /* 16-bit version */ data8 sys_setfsgid /* 16-bit version */
data8 sys_llseek /* 140 */ data8 sys_llseek /* 140 */
data8 sys32_getdents data8 compat_sys_getdents
data8 compat_sys_select data8 compat_sys_select
data8 sys_flock data8 sys_flock
data8 sys32_msync data8 sys32_msync
...@@ -428,7 +428,7 @@ ia32_syscall_table: ...@@ -428,7 +428,7 @@ ia32_syscall_table:
data8 sys_pivot_root data8 sys_pivot_root
data8 sys_mincore data8 sys_mincore
data8 sys_madvise data8 sys_madvise
data8 sys_getdents64 /* 220 */ data8 compat_sys_getdents64 /* 220 */
data8 compat_sys_fcntl64 data8 compat_sys_fcntl64
data8 sys_ni_syscall /* reserved for TUX */ data8 sys_ni_syscall /* reserved for TUX */
data8 sys_ni_syscall /* reserved for Security */ data8 sys_ni_syscall /* reserved for Security */
......
...@@ -34,6 +34,7 @@ ...@@ -34,6 +34,7 @@
#include <linux/syscalls.h> #include <linux/syscalls.h>
#include <linux/ctype.h> #include <linux/ctype.h>
#include <linux/module.h> #include <linux/module.h>
#include <linux/dirent.h>
#include <linux/dnotify.h> #include <linux/dnotify.h>
#include <linux/highuid.h> #include <linux/highuid.h>
#include <linux/sunrpc/svc.h> #include <linux/sunrpc/svc.h>
...@@ -797,6 +798,260 @@ asmlinkage long compat_sys_mount(char __user * dev_name, char __user * dir_name, ...@@ -797,6 +798,260 @@ asmlinkage long compat_sys_mount(char __user * dev_name, char __user * dir_name,
return retval; return retval;
} }
#define NAME_OFFSET(de) ((int) ((de)->d_name - (char __user *) (de)))
#define COMPAT_ROUND_UP(x) (((x)+sizeof(compat_long_t)-1) & \
~(sizeof(compat_long_t)-1))
struct compat_old_linux_dirent {
compat_ulong_t d_ino;
compat_ulong_t d_offset;
unsigned short d_namlen;
char d_name[1];
};
struct compat_readdir_callback {
struct compat_old_linux_dirent __user *dirent;
int result;
};
static int compat_fillonedir(void *__buf, const char *name, int namlen,
loff_t offset, ino_t ino, unsigned int d_type)
{
struct compat_readdir_callback *buf = __buf;
struct compat_old_linux_dirent __user *dirent;
if (buf->result)
return -EINVAL;
buf->result++;
dirent = buf->dirent;
if (!access_ok(VERIFY_WRITE, (unsigned long)dirent,
(unsigned long)(dirent->d_name + namlen + 1) -
(unsigned long)dirent))
goto efault;
if ( __put_user(ino, &dirent->d_ino) ||
__put_user(offset, &dirent->d_offset) ||
__put_user(namlen, &dirent->d_namlen) ||
__copy_to_user(dirent->d_name, name, namlen) ||
__put_user(0, dirent->d_name + namlen))
goto efault;
return 0;
efault:
buf->result = -EFAULT;
return -EFAULT;
}
asmlinkage long compat_old_readdir(unsigned int fd,
struct compat_old_linux_dirent __user *dirent, unsigned int count)
{
int error;
struct file *file;
struct compat_readdir_callback buf;
error = -EBADF;
file = fget(fd);
if (!file)
goto out;
buf.result = 0;
buf.dirent = dirent;
error = vfs_readdir(file, compat_fillonedir, &buf);
if (error >= 0)
error = buf.result;
fput(file);
out:
return error;
}
struct compat_linux_dirent {
compat_ulong_t d_ino;
compat_ulong_t d_off;
unsigned short d_reclen;
char d_name[1];
};
struct compat_getdents_callback {
struct compat_linux_dirent __user *current_dir;
struct compat_linux_dirent __user *previous;
int count;
int error;
};
static int compat_filldir(void *__buf, const char *name, int namlen,
loff_t offset, ino_t ino, unsigned int d_type)
{
struct compat_linux_dirent __user * dirent;
struct compat_getdents_callback *buf = __buf;
int reclen = COMPAT_ROUND_UP(NAME_OFFSET(dirent) + namlen + 2);
buf->error = -EINVAL; /* only used if we fail.. */
if (reclen > buf->count)
return -EINVAL;
dirent = buf->previous;
if (dirent) {
if (__put_user(offset, &dirent->d_off))
goto efault;
}
dirent = buf->current_dir;
if (__put_user(ino, &dirent->d_ino))
goto efault;
if (__put_user(reclen, &dirent->d_reclen))
goto efault;
if (copy_to_user(dirent->d_name, name, namlen))
goto efault;
if (__put_user(0, dirent->d_name + namlen))
goto efault;
if (__put_user(d_type, (char __user *) dirent + reclen - 1))
goto efault;
buf->previous = dirent;
dirent = (void __user *)dirent + reclen;
buf->current_dir = dirent;
buf->count -= reclen;
return 0;
efault:
buf->error = -EFAULT;
return -EFAULT;
}
asmlinkage long compat_sys_getdents(unsigned int fd,
struct compat_linux_dirent __user *dirent, unsigned int count)
{
struct file * file;
struct compat_linux_dirent __user * lastdirent;
struct compat_getdents_callback buf;
int error;
error = -EFAULT;
if (!access_ok(VERIFY_WRITE, dirent, count))
goto out;
error = -EBADF;
file = fget(fd);
if (!file)
goto out;
buf.current_dir = dirent;
buf.previous = NULL;
buf.count = count;
buf.error = 0;
error = vfs_readdir(file, compat_filldir, &buf);
if (error < 0)
goto out_putf;
error = buf.error;
lastdirent = buf.previous;
if (lastdirent) {
if (put_user(file->f_pos, &lastdirent->d_off))
error = -EFAULT;
else
error = count - buf.count;
}
out_putf:
fput(file);
out:
return error;
}
#ifndef __ARCH_OMIT_COMPAT_SYS_GETDENTS64
#define COMPAT_ROUND_UP64(x) (((x)+sizeof(u64)-1) & ~(sizeof(u64)-1))
struct compat_getdents_callback64 {
struct linux_dirent64 __user *current_dir;
struct linux_dirent64 __user *previous;
int count;
int error;
};
static int compat_filldir64(void * __buf, const char * name, int namlen, loff_t offset,
ino_t ino, unsigned int d_type)
{
struct linux_dirent64 __user *dirent;
struct compat_getdents_callback64 *buf = __buf;
int jj = NAME_OFFSET(dirent);
int reclen = COMPAT_ROUND_UP64(jj + namlen + 1);
u64 off;
buf->error = -EINVAL; /* only used if we fail.. */
if (reclen > buf->count)
return -EINVAL;
dirent = buf->previous;
if (dirent) {
if (__put_user(offset, (u32 __user *)&dirent->d_off))
goto efault;
if (__put_user(offset >> 32,
((u32 __user *)&dirent->d_off) + 1))
goto efault;
}
dirent = buf->current_dir;
if ((__put_user(ino, (u32 __user *)&dirent->d_ino))
|| (__put_user(ino >> 32, ((u32 __user *)&dirent->d_ino) + 1)))
goto efault;
off = 0;
if ((__put_user(off, (u32 __user *)&dirent->d_off))
|| (__put_user(off >> 32, ((u32 __user *)&dirent->d_off) + 1)))
goto efault;
if (__put_user(reclen, &dirent->d_reclen))
goto efault;
if (__put_user(d_type, &dirent->d_type))
goto efault;
if (copy_to_user(dirent->d_name, name, namlen))
goto efault;
if (__put_user(0, dirent->d_name + namlen))
goto efault;
buf->previous = dirent;
dirent = (void __user *)dirent + reclen;
buf->current_dir = dirent;
buf->count -= reclen;
return 0;
efault:
buf->error = -EFAULT;
return -EFAULT;
}
asmlinkage long compat_sys_getdents64(unsigned int fd,
struct linux_dirent64 __user * dirent, unsigned int count)
{
struct file * file;
struct linux_dirent64 __user * lastdirent;
struct compat_getdents_callback64 buf;
int error;
error = -EFAULT;
if (!access_ok(VERIFY_WRITE, dirent, count))
goto out;
error = -EBADF;
file = fget(fd);
if (!file)
goto out;
buf.current_dir = dirent;
buf.previous = NULL;
buf.count = count;
buf.error = 0;
error = vfs_readdir(file, compat_filldir64, &buf);
if (error < 0)
goto out_putf;
error = buf.error;
lastdirent = buf.previous;
if (lastdirent) {
typeof(lastdirent->d_off) d_off = file->f_pos;
__put_user(d_off, (u32 __user *)&lastdirent->d_off);
__put_user(d_off >> 32, ((u32 __user *)&lastdirent->d_off) + 1);
error = count - buf.count;
}
out_putf:
fput(file);
out:
return error;
}
#endif /* ! __ARCH_OMIT_COMPAT_SYS_GETDENTS64 */
static ssize_t compat_do_readv_writev(int type, struct file *file, static ssize_t compat_do_readv_writev(int type, struct file *file,
const struct compat_iovec __user *uvector, const struct compat_iovec __user *uvector,
unsigned long nr_segs, loff_t *pos) unsigned long nr_segs, loff_t *pos)
......
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