• Tyler Hicks's avatar
    eCryptfs: Remove mmap from directory operations · 38e3eaee
    Tyler Hicks authored
    Adrian reported that mkfontscale didn't work inside of eCryptfs mounts.
    Strace revealed the following:
    
    open("./", O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY|O_CLOEXEC) = 3
    fcntl64(3, F_GETFD) = 0x1 (flags FD_CLOEXEC)
    open("./fonts.scale", O_WRONLY|O_CREAT|O_TRUNC, 0666) = 4
    getdents(3, /* 80 entries */, 32768) = 2304
    open("./.", O_RDONLY) = 5
    fcntl64(5, F_SETFD, FD_CLOEXEC) = 0
    fstat64(5, {st_mode=S_IFDIR|0755, st_size=16384, ...}) = 0
    mmap2(NULL, 16384, PROT_READ, MAP_PRIVATE, 5, 0) = 0xb7fcf000
    close(5) = 0
    --- SIGBUS (Bus error) @ 0 (0) ---
    +++ killed by SIGBUS +++
    
    The mmap2() on a directory was successful, resulting in a SIGBUS
    signal later.  This patch removes mmap() from the list of possible
    ecryptfs_dir_fops so that mmap() isn't possible on eCryptfs directory
    files.
    
    https://bugs.launchpad.net/ecryptfs/+bug/400443Reported-by: default avatarAdrian C. <anrxc@sysphere.org>
    Signed-off-by: default avatarTyler Hicks <tyhicks@linux.vnet.ibm.com>
    38e3eaee
file.c 10.1 KB