Max Vozeler wrote:
> Does the attached version do the right thing in this regard? It
> works for me and takes the normal code path if lo_file_name doesn't
> match the loopfile that was given in *spec.
Your version compared device (or file) names. Comparing names is problematic
because they may be truncated or they may use relative paths (not begin with
slash). I changed it to compare device number and inode number of the block
special file (or normal file) to those recorded in loop device.
# losetup /dev/loop6
/dev/loop6: [0902]:213045 (/dev/md5) offset=4096 encryption=AES128 multi-key-v3
^^^^ ^^^^^^
| |
| Inode number inside my root file system where static
| block special node /dev/md5 happens to reside.
|
Device number of my root file system where static
block special node /dev/md5 happens to reside.
I merged your patch, but now the code looks like this:
int is_loop_active(const char *dev, const char *backdev)
{
int fd;
int ret = 0;
struct stat statbuf;
struct loop_info64 loopinfo;
if (stat (dev, &statbuf) == 0 && S_ISBLK(statbuf.st_mode)) {
fd = open (dev, O_RDONLY);
if (fd < 0)
return 0;
if ((loop_get_status64_ioctl(fd, &loopinfo) == 0)
&& (stat (backdev, &statbuf) == 0)
&& (statbuf.st_dev == loopinfo.lo_device)
&& (statbuf.st_ino == loopinfo.lo_inode))
ret = 1; /* backing device matches */
memset(&loopinfo, 0, sizeof(loopinfo));
close(fd);
}
return ret;
}
--
Jari Ruusu 1024R/3A220F51 5B 4B F9 BB D3 3F 52 E9 DB 1D EB E3 24 0E A9 DD
-
Linux-crypto: cryptography in and on the Linux system
Archive: http://mail.nl.linux.org/linux-crypto/
