• Theodore Ts'o's avatar
    ext4: avoid declaring fs inconsistent due to invalid file handles · 8a363970
    Theodore Ts'o authored
    If we receive a file handle, either from NFS or open_by_handle_at(2),
    and it points at an inode which has not been initialized, and the file
    system has metadata checksums enabled, we shouldn't try to get the
    inode, discover the checksum is invalid, and then declare the file
    system as being inconsistent.
    
    This can be reproduced by creating a test file system via "mke2fs -t
    ext4 -O metadata_csum /tmp/foo.img 8M", mounting it, cd'ing into that
    directory, and then running the following program.
    
    #define _GNU_SOURCE
    #include <fcntl.h>
    
    struct handle {
    	struct file_handle fh;
    	unsigned char fid[MAX_HANDLE_SZ];
    };
    
    int main(int argc, char **argv)
    {
    	struct handle h = {{8, 1 }, { 12, }};
    
    	open_by_handle_at(AT_FDCWD, &h.fh, O_RDONLY);
    	return 0;
    }
    
    Google-Bug-Id: 120690101
    Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
    Cc: stable@kernel.org
    8a363970
ialloc.c 39.6 KB