Merge commit 'v2.6.30' into for-2.6.31

[safe/jmp/linux-2.6] / fs / compat.c

diff --git a/fs/compat.c b/fs/compat.c
index 5e374aa..681ed81 100644 (file)
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -51,6 +51,7 @@
 #include <linux/poll.h>
 #include <linux/mm.h>
 #include <linux/eventpoll.h>
+#include <linux/fs_struct.h>
 
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
@@ -180,22 +181,24 @@ asmlinkage long compat_sys_newstat(char __user * filename,
                struct compat_stat __user *statbuf)
 {
        struct kstat stat;
-       int error = vfs_stat_fd(AT_FDCWD, filename, &stat);
+       int error;
 
-       if (!error)
-               error = cp_compat_stat(&stat, statbuf);
-       return error;
+       error = vfs_stat(filename, &stat);
+       if (error)
+               return error;
+       return cp_compat_stat(&stat, statbuf);
 }
 
 asmlinkage long compat_sys_newlstat(char __user * filename,
                struct compat_stat __user *statbuf)
 {
        struct kstat stat;
-       int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);
+       int error;
 
-       if (!error)
-               error = cp_compat_stat(&stat, statbuf);
-       return error;
+       error = vfs_lstat(filename, &stat);
+       if (error)
+               return error;
+       return cp_compat_stat(&stat, statbuf);
 }
 
 #ifndef __ARCH_WANT_STAT64
@@ -203,21 +206,12 @@ asmlinkage long compat_sys_newfstatat(unsigned int dfd, char __user *filename,
                struct compat_stat __user *statbuf, int flag)
 {
        struct kstat stat;
-       int error = -EINVAL;
-
-       if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
-               goto out;
-
-       if (flag & AT_SYMLINK_NOFOLLOW)
-               error = vfs_lstat_fd(dfd, filename, &stat);
-       else
-               error = vfs_stat_fd(dfd, filename, &stat);
-
-       if (!error)
-               error = cp_compat_stat(&stat, statbuf);
+       int error;
 
-out:
-       return error;
+       error = vfs_fstatat(dfd, filename, &stat, flag);
+       if (error)
+               return error;
+       return cp_compat_stat(&stat, statbuf);
 }
 #endif
 
@@ -1195,16 +1189,12 @@ out:
        return ret;
 }
 
-asmlinkage ssize_t
-compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec, unsigned long vlen)
+static size_t compat_readv(struct file *file,
+                          const struct compat_iovec __user *vec,
+                          unsigned long vlen, loff_t *pos)
 {
-       struct file *file;
        ssize_t ret = -EBADF;
 
-       file = fget(fd);
-       if (!file)
-               return -EBADF;
-
        if (!(file->f_mode & FMODE_READ))
                goto out;
 
@@ -1212,25 +1202,56 @@ compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec, unsign
        if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read))
                goto out;
 
-       ret = compat_do_readv_writev(READ, file, vec, vlen, &file->f_pos);
+       ret = compat_do_readv_writev(READ, file, vec, vlen, pos);
 
 out:
        if (ret > 0)
                add_rchar(current, ret);
        inc_syscr(current);
-       fput(file);
        return ret;
 }
 
 asmlinkage ssize_t
-compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec, unsigned long vlen)
+compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec,
+                unsigned long vlen)
 {
        struct file *file;
-       ssize_t ret = -EBADF;
+       int fput_needed;
+       ssize_t ret;
 
-       file = fget(fd);
+       file = fget_light(fd, &fput_needed);
+       if (!file)
+               return -EBADF;
+       ret = compat_readv(file, vec, vlen, &file->f_pos);
+       fput_light(file, fput_needed);
+       return ret;
+}
+
+asmlinkage ssize_t
+compat_sys_preadv(unsigned long fd, const struct compat_iovec __user *vec,
+                 unsigned long vlen, u32 pos_low, u32 pos_high)
+{
+       loff_t pos = ((loff_t)pos_high << 32) | pos_low;
+       struct file *file;
+       int fput_needed;
+       ssize_t ret;
+
+       if (pos < 0)
+               return -EINVAL;
+       file = fget_light(fd, &fput_needed);
        if (!file)
                return -EBADF;
+       ret = compat_readv(file, vec, vlen, &pos);
+       fput_light(file, fput_needed);
+       return ret;
+}
+
+static size_t compat_writev(struct file *file,
+                           const struct compat_iovec __user *vec,
+                           unsigned long vlen, loff_t *pos)
+{
+       ssize_t ret = -EBADF;
+
        if (!(file->f_mode & FMODE_WRITE))
                goto out;
 
@@ -1238,13 +1259,47 @@ compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec, unsig
        if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write))
                goto out;
 
-       ret = compat_do_readv_writev(WRITE, file, vec, vlen, &file->f_pos);
+       ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos);
 
 out:
        if (ret > 0)
                add_wchar(current, ret);
        inc_syscw(current);
-       fput(file);
+       return ret;
+}
+
+asmlinkage ssize_t
+compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec,
+                 unsigned long vlen)
+{
+       struct file *file;
+       int fput_needed;
+       ssize_t ret;
+
+       file = fget_light(fd, &fput_needed);
+       if (!file)
+               return -EBADF;
+       ret = compat_writev(file, vec, vlen, &file->f_pos);
+       fput_light(file, fput_needed);
+       return ret;
+}
+
+asmlinkage ssize_t
+compat_sys_pwritev(unsigned long fd, const struct compat_iovec __user *vec,
+                  unsigned long vlen, u32 pos_low, u32 pos_high)
+{
+       loff_t pos = ((loff_t)pos_high << 32) | pos_low;
+       struct file *file;
+       int fput_needed;
+       ssize_t ret;
+
+       if (pos < 0)
+               return -EINVAL;
+       file = fget_light(fd, &fput_needed);
+       if (!file)
+               return -EBADF;
+       ret = compat_writev(file, vec, vlen, &pos);
+       fput_light(file, fput_needed);
        return ret;
 }
 
@@ -1420,12 +1475,18 @@ int compat_do_execve(char * filename,
 {
        struct linux_binprm *bprm;
        struct file *file;
+       struct files_struct *displaced;
+       bool clear_in_exec;
        int retval;
 
+       retval = unshare_files(&displaced);
+       if (retval)
+               goto out_ret;
+
        retval = -ENOMEM;
        bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
        if (!bprm)
-               goto out_ret;
+               goto out_files;
 
        retval = mutex_lock_interruptible(&current->cred_exec_mutex);
        if (retval < 0)
@@ -1436,12 +1497,16 @@ int compat_do_execve(char * filename,
        bprm->cred = prepare_exec_creds();
        if (!bprm->cred)
                goto out_unlock;
-       check_unsafe_exec(bprm, current->files);
+
+       retval = check_unsafe_exec(bprm);
+       if (retval < 0)
+               goto out_unlock;
+       clear_in_exec = retval;
 
        file = open_exec(filename);
        retval = PTR_ERR(file);
        if (IS_ERR(file))
-               goto out_unlock;
+               goto out_unmark;
 
        sched_exec();
 
@@ -1483,10 +1548,13 @@ int compat_do_execve(char * filename,
                goto out;
 
        /* execve succeeded */
+       current->fs->in_exec = 0;
        current->in_execve = 0;
        mutex_unlock(&current->cred_exec_mutex);
        acct_update_integrals(current);
        free_bprm(bprm);
+       if (displaced)
+               put_files_struct(displaced);
        return retval;
 
 out:
@@ -1499,6 +1567,10 @@ out_file:
                fput(bprm->file);
        }
 
+out_unmark:
+       if (clear_in_exec)
+               current->fs->in_exec = 0;
+
 out_unlock:
        current->in_execve = 0;
        mutex_unlock(&current->cred_exec_mutex);
@@ -1506,6 +1578,9 @@ out_unlock:
 out_free:
        free_bprm(bprm);
 
+out_files:
+       if (displaced)
+               reset_files_struct(displaced);
 out_ret:
        return retval;
 }