Commit 039c4d7a authored by Trond Myklebust's avatar Trond Myklebust

NFS: Fix up a race in the NFS implementation of GETLK

 ...and fix a memory corruption bug due to improper use of memcpy() on
 a struct file_lock.
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 06735b34
...@@ -376,22 +376,31 @@ nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t ...@@ -376,22 +376,31 @@ nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t
static int do_getlk(struct file *filp, int cmd, struct file_lock *fl) static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
{ {
struct file_lock *cfl;
struct inode *inode = filp->f_mapping->host; struct inode *inode = filp->f_mapping->host;
int status = 0; int status = 0;
lock_kernel(); lock_kernel();
/* Use local locking if mounted with "-onolock" */ /* Try local locking first */
if (!(NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)) cfl = posix_test_lock(filp, fl);
status = NFS_PROTO(inode)->lock(filp, cmd, fl); if (cfl != NULL) {
else { locks_copy_lock(fl, cfl);
struct file_lock *cfl = posix_test_lock(filp, fl); goto out;
fl->fl_type = F_UNLCK;
if (cfl != NULL)
memcpy(fl, cfl, sizeof(*fl));
} }
if (nfs_have_delegation(inode, FMODE_READ))
goto out_noconflict;
if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM)
goto out_noconflict;
status = NFS_PROTO(inode)->lock(filp, cmd, fl);
out:
unlock_kernel(); unlock_kernel();
return status; return status;
out_noconflict:
fl->fl_type = F_UNLCK;
goto out;
} }
static int do_vfs_lock(struct file *file, struct file_lock *fl) static int do_vfs_lock(struct file *file, struct file_lock *fl)
......
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