From: J. Bruce Fields Date: Thu, 10 May 2007 22:38:43 +0000 (-0400) Subject: locks: fix F_GETLK regression (failure to find conflicts) X-Git-Tag: v2.6.22-rc1~104 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=129a84de2347002f09721cda3155ccfd19fade40;p=linux-2.6 locks: fix F_GETLK regression (failure to find conflicts) In 9d6a8c5c213e34c475e72b245a8eb709258e968c we changed posix_test_lock to modify its single file_lock argument instead of taking separate input and output arguments. This makes it no longer safe to set the output lock's fl_type to F_UNLCK before looking for a conflict, since that means searching for a conflict against a lock with type F_UNLCK. This fixes a regression which causes F_GETLK to incorrectly report no conflict on most filesystems (including any filesystem that doesn't do its own locking). Also fix posix_lock_to_flock() to copy the lock type. This isn't strictly necessary, since the caller already does this; but it seems less likely to cause confusion in the future. Thanks to Doug Chapman for the bug report. Signed-off-by: "J. Bruce Fields" Acked-by: Doug Chapman Signed-off-by: Linus Torvalds --- diff --git a/fs/locks.c b/fs/locks.c index 671a034dc9..8ec16ab5ef 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -669,7 +669,6 @@ posix_test_lock(struct file *filp, struct file_lock *fl) { struct file_lock *cfl; - fl->fl_type = F_UNLCK; lock_kernel(); for (cfl = filp->f_path.dentry->d_inode->i_flock; cfl; cfl = cfl->fl_next) { if (!IS_POSIX(cfl)) @@ -681,7 +680,8 @@ posix_test_lock(struct file *filp, struct file_lock *fl) __locks_copy_lock(fl, cfl); unlock_kernel(); return 1; - } + } else + fl->fl_type = F_UNLCK; unlock_kernel(); return 0; } @@ -1632,6 +1632,7 @@ static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl) flock->l_len = fl->fl_end == OFFSET_MAX ? 0 : fl->fl_end - fl->fl_start + 1; flock->l_whence = 0; + flock->l_type = fl->fl_type; return 0; }