Hello Amir Goldstein,
This is a semi-automatic email about new static checker warnings.
The patch 40a100d3adc1: "fsnotify: pass dir and inode arguments to
fsnotify()" from Jul 22, 2020, leads to the following Smatch
complaint:
fs/notify/fsnotify.c:460 fsnotify()
warn: variable dereferenced before check 'inode' (see line 449)
fs/notify/fsnotify.c
448 }
449 sb = inode->i_sb;
^^^^^^^^^^^
New dreference.
450
451 /*
452 * Optimization: srcu_read_lock() has a memory barrier which can
453 * be expensive. It protects walking the *_fsnotify_marks lists.
454 * However, if we do not walk the lists, we do not have to do
455 * SRCU because we have no references to any objects and do not
456 * need SRCU to keep them "alive".
457 */
458 if (!sb->s_fsnotify_marks &&
459 (!mnt || !mnt->mnt_fsnotify_marks) &&
460 (!inode || !inode->i_fsnotify_marks) &&
^^^^^^
Check too late. Presumably this check can be removed?
461 (!child || !child->i_fsnotify_marks))
462 return 0;
regards,
dan carpenter
