forked from luck/tmp_suning_uos_patched
dlmfs_file_write(): fix the bogosity in handling non-zero *ppos
'count' is how much you want written, not the final position. Moreover, it can legitimately be less than the current position... Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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@ -275,7 +275,6 @@ static ssize_t dlmfs_file_write(struct file *filp,
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loff_t *ppos)
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loff_t *ppos)
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{
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{
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int bytes_left;
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int bytes_left;
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ssize_t writelen;
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char *lvb_buf;
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char *lvb_buf;
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struct inode *inode = file_inode(filp);
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struct inode *inode = file_inode(filp);
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@ -285,32 +284,30 @@ static ssize_t dlmfs_file_write(struct file *filp,
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if (*ppos >= i_size_read(inode))
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if (*ppos >= i_size_read(inode))
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return -ENOSPC;
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return -ENOSPC;
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/* don't write past the lvb */
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if (count > i_size_read(inode) - *ppos)
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count = i_size_read(inode) - *ppos;
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if (!count)
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if (!count)
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return 0;
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return 0;
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if (!access_ok(buf, count))
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if (!access_ok(buf, count))
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return -EFAULT;
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return -EFAULT;
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/* don't write past the lvb */
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lvb_buf = kmalloc(count, GFP_NOFS);
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if ((count + *ppos) > i_size_read(inode))
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writelen = i_size_read(inode) - *ppos;
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else
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writelen = count - *ppos;
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lvb_buf = kmalloc(writelen, GFP_NOFS);
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if (!lvb_buf)
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if (!lvb_buf)
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return -ENOMEM;
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return -ENOMEM;
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bytes_left = copy_from_user(lvb_buf, buf, writelen);
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bytes_left = copy_from_user(lvb_buf, buf, count);
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writelen -= bytes_left;
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count -= bytes_left;
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if (writelen)
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if (count)
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user_dlm_write_lvb(inode, lvb_buf, writelen);
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user_dlm_write_lvb(inode, lvb_buf, count);
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kfree(lvb_buf);
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kfree(lvb_buf);
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*ppos = *ppos + writelen;
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*ppos = *ppos + count;
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mlog(0, "wrote %zd bytes\n", writelen);
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mlog(0, "wrote %zu bytes\n", count);
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return writelen;
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return count;
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}
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}
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static void dlmfs_init_once(void *foo)
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static void dlmfs_init_once(void *foo)
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