Fix a race condition in FASYNC handling

[linux-2.6-omap-h63xx.git] / fs / ioctl.c

diff --git a/fs/ioctl.c b/fs/ioctl.c
index 33a6b7ecb8b8686449fb42b1ab5f8ef6ce64709f..43e8b2c0664b1b3d302a6d46e3fa40185edb5ae7 100644 (file)
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -226,6 +226,8 @@ static int ioctl_fiemap(struct file *filp, unsigned long arg)
        return error;
 }
 
+#ifdef CONFIG_BLOCK
+
 #define blk_to_logical(inode, blk) (blk << (inode)->i_blkbits)
 #define logical_to_blk(inode, offset) (offset >> (inode)->i_blkbits);
 
@@ -342,6 +344,8 @@ int generic_block_fiemap(struct inode *inode,
 }
 EXPORT_SYMBOL(generic_block_fiemap);
 
+#endif  /*  CONFIG_BLOCK  */
+
 static int file_ioctl(struct file *filp, unsigned int cmd,
                unsigned long arg)
 {
@@ -396,11 +400,9 @@ static int ioctl_fioasync(unsigned int fd, struct file *filp,
 
        /* Did FASYNC state change ? */
        if ((flag ^ filp->f_flags) & FASYNC) {
-               if (filp->f_op && filp->f_op->fasync) {
-                       lock_kernel();
+               if (filp->f_op && filp->f_op->fasync)
                        error = filp->f_op->fasync(fd, filp, on);
-                       unlock_kernel();
-               } else
+               else
                        error = -ENOTTY;
        }
        if (error)
@@ -436,11 +438,17 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
                break;
 
        case FIONBIO:
+               /* BKL needed to avoid races tweaking f_flags */
+               lock_kernel();
                error = ioctl_fionbio(filp, argp);
+               unlock_kernel();
                break;
 
        case FIOASYNC:
+               /* BKL needed to avoid races tweaking f_flags */
+               lock_kernel();
                error = ioctl_fioasync(fd, filp, argp);
+               unlock_kernel();
                break;
 
        case FIOQSIZE: