• Theodore Ts'o's avatar
    ext4: fix race when setting bitmap_uptodate flag · 813e5727
    Theodore Ts'o authored
    In ext4_read_{inode,block}_bitmap() we were setting bitmap_uptodate()
    before submitting the buffer for read.  The is bad, since we check
    bitmap_uptodate() without locking the buffer, and so if another
    process is racing with us, it's possible that they will think the
    bitmap is uptodate even though the read has not completed yet,
    resulting in inodes and blocks potentially getting allocated more than
    once if we get really unlucky.
    
    Addresses-Google-Bug: 2828254
    Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
    813e5727
ext4.h 82.5 KB