Fix SEEK_END seeking twice as far as requested. Centralize lseek handling in
one place and avoid overflow bugs. Inode lseek handlers now only need to
handle SEEK_END with offset 0. Prevent the file offset from ever going below
zero or overflowing.
Character devices are now not seekable, but lseek will pretend they are, yet
always stay at the file offset 0. pread/pwrite on character devices will now
ignore the file offset and call read/write.
This change prevents character devices from being memory mapped, notably
/dev/zero can no longer be memory mapped. None of the current ports seem
to rely on this behavior and will work with just MAP_ANONYMOUS.
Refactor read and write system calls to have a shared return statement for
both seekable and non-seekable IO.
Fix file offset overflow bugs in read and write system calls.
Fix system calls returning EPERM instead of properly returning EBADF when
the file has not been opened in the right mode.
Truncate IO counts and total vector IO length so the IO operation does not
do any IO beyond OFF_MAX. Truncate also total vector IO length for recvmsg
and sendmsg. Fail with EINVAL if total vector IO length exceeds SSIZE_MAX.
Don't stop early if the total IO length is zero, so zero length IO now block
on any locks internal to the inode.
Handle reads at the maximum file offset with an end of file condition and
handle writes of at least one byte at the maximum file offset by failing
with EFBIG.
Refactor UtilMemoryBuffer to store the file size using off_t instead of
size_t to avoid casts and keep file sizes in the off_t type. Properly
handle errors in the code, such as failing with EROFS instead of EBADF if
the backing memory is not writeable, and failing with EFBIG if writing
beyond the end of the file.
Fix mkpartition not rejecting invalid partition start offsets and lengths.
Strictly enforce partition start and length checks in the partition code.
Enforce partitions exist within regular files or block devices.
Fix a few indention issues.
When entropy gathering is implemented, in the case of the installer and
upgrader, the system probably won't have any entropy when it begins. By the
time the system is installed, there will probably be a bit of entropy from
the user using the system and general system usage, so mix in some of that.
In the case of init, after an installed system has run for a while, a lot of
entropy will have gotten collected, but init will have its arc4random seeded
with initial boot entry, so mix in some fresh entropy, so the random seed
written on shutdown remains as entropic as possible.
The commit 0def94568a switched to the box
drawing light vertical (U+2502) character, but did not fix the now wrong
assumption that the line drawing character encoded to a single byte.
OpenSSH is allocating a fd_set of exactly the needed size, which leads to
buffer overflows in select(2) when it tries to zero out the fd_set assuming
it is the normal size.
