[PATCH v5 07/14] locks: consolidate checks for compatible filp->f_mode values in setlk handlers

From: Jeff Layton
Date: Thu Jan 09 2014 - 09:25:08 EST


Move this check into flock64_to_posix_lock instead of duplicating it in
two places. This also fixes a minor wart in the code where we continue
referring to the struct flock after converting it to struct file_lock.

Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/locks.c | 46 ++++++++++++----------------------------------
1 file changed, 12 insertions(+), 34 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index b49e853..4cd2578 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -388,6 +388,18 @@ static int flock64_to_posix_lock(struct file *filp, struct file_lock *fl,
fl->fl_ops = NULL;
fl->fl_lmops = NULL;

+ /* Ensure that fl->fl_filp has compatible f_mode */
+ switch (l->l_type) {
+ case F_RDLCK:
+ if (!(filp->f_mode & FMODE_READ))
+ return -EBADF;
+ break;
+ case F_WRLCK:
+ if (!(filp->f_mode & FMODE_WRITE))
+ return -EBADF;
+ break;
+ }
+
return assign_type(fl, l->l_type);
}

@@ -2025,23 +2037,6 @@ again:
file_lock->fl_flags |= FL_SLEEP;
}

- error = -EBADF;
- switch (flock.l_type) {
- case F_RDLCK:
- if (!(filp->f_mode & FMODE_READ))
- goto out;
- break;
- case F_WRLCK:
- if (!(filp->f_mode & FMODE_WRITE))
- goto out;
- break;
- case F_UNLCK:
- break;
- default:
- error = -EINVAL;
- goto out;
- }
-
error = do_lock_file_wait(filp, cmd, file_lock);

/*
@@ -2143,23 +2138,6 @@ again:
file_lock->fl_flags |= FL_SLEEP;
}

- error = -EBADF;
- switch (flock.l_type) {
- case F_RDLCK:
- if (!(filp->f_mode & FMODE_READ))
- goto out;
- break;
- case F_WRLCK:
- if (!(filp->f_mode & FMODE_WRITE))
- goto out;
- break;
- case F_UNLCK:
- break;
- default:
- error = -EINVAL;
- goto out;
- }
-
error = do_lock_file_wait(filp, cmd, file_lock);

/*
--
1.8.4.2

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