Commit graph

54 commits

Author SHA1 Message Date
Thomas Veerman
9233fdb359 AVFS: make forbidden check for specific proc instead of fp 2012-01-30 15:16:20 +00:00
Thomas Veerman
0e537f1085 AVFS: initialize root FS before receiving new work 2012-01-30 15:16:20 +00:00
Thomas Veerman
0bd011affd PM: extend srv_fork to set a specific UID
Currently, all servers and drivers run as root as they are forks of
RS. srv_fork now tells PM with which credentials to run the resulting
fork. Subsequently, PM lets VFS now as well.

This patch also fixes the following bugs:
 - RS doesn't initialize the setugid variable during exec, causing the
   servers and drivers to run setuid rendering the srv_fork extension
   useless.
 - PM erroneously tells VFS to run processes setuid. This doesn't
   actually lead to setuid processes as VFS sets {r,e}uid and {r,e}gid
   properly before checking PM's approval.
2012-01-30 15:16:19 +00:00
Thomas Veerman
e894c9e1b5 Don't print events that happen often 2012-01-19 17:06:14 +00:00
Thomas Veerman
700641afb8 lseek should not yield a negative file position 2012-01-19 16:48:01 +00:00
Thomas Veerman
ddbdca6cdb Add support for survival of crashed FSs
When an FS crashes, VFS will clean up resources tied to that FS:
 - Pending requests to the FS are canceled (i.e., fail with EIO)
 - Threads waiting for a reply are stopped (i.e., fail with EIO)
 - Open files are marked invalid. Future operations on a file descriptor
   will cause EBADF errors.
 - vmnt entry is cleared, so in-flight system calls that got past the
   file descriptor check but not yet talking to the crashed FS, will
   fail with EIO.
 - The reference counter of the mount point is decreased, effectively
   removing the crashed FS from the file system tree. Descendants of
   this part of the tree are unreachable by means of a path, but can
   still be unmounted by feeding the block special file to unmount(2).

This patch also gets rid of the "not a known driver endpoint" messages
during shutdown.
2012-01-19 14:21:46 +00:00
Thomas Veerman
f18dab92bf Remove unused variable 2012-01-16 10:12:29 +00:00
Thomas Veerman
078adc7ed7 Increase thread stack space for GCC compiled images 2012-01-16 10:12:29 +00:00
Thomas Veerman
e6c98c3c55 AVFS: Return actual last dir when path is named by a symlink
Last_dir didn't consider paths that end in a symlink and hence didn't
actually return the last_dir when provided with one. For example,
/var/log is a symlink to /usr/log. Issuing `>/var/log' would trigger
an assert in AVFS, because /var/ is not the actual last directory; /usr/
is.

Last_dir now verifies the final component is not a symlink. If it is, it
follows the symlink and restarts finding of the last the directory.
2012-01-16 10:12:29 +00:00
David van Moolenbroek
c89aaf7a87 vfs/avfs: renumber stat calls so as to be unique
The old stat call numbers are still supported for a while.
2012-01-14 00:27:07 +01:00
David van Moolenbroek
2c685f34e0 Cut PM out of the adddma/deldma/getdma call path 2012-01-14 00:27:06 +01:00
David van Moolenbroek
8cb7ba7951 Remove obsolete PROCSTAT/getsigset call. 2012-01-14 00:27:06 +01:00
Thomas Veerman
a4d01f8a83 Fix tll state bug
When a lock has read-serialized and read-only locks, releasing the read-
serialized lock would not set the state to read-only when no other locks
were pending.
2012-01-12 11:30:24 +00:00
David van Moolenbroek
c25e2eb0cf avfs: fix for root file system not being unmounted
Also no longer have avfs crash whenever a file system server crashes.
2012-01-04 14:10:10 +01:00
Ben Gras
34a8901eb8 vfs,avfs: verify an interpreter was found on #! line
. if not, NULL *interp is dereferenced
2011-12-21 23:44:13 +01:00
Thomas Veerman
de5a9a3e8b AVFS: Use scratchpad instead of m_in to pass around file descriptors
Some code relies on having the file descriptor in m_in.fd. Consequently,
m_in is not only used to provide syscall parameters from user space to
VFS, but also as a global variable to store temporary data within VFS.
This has the ugly side effect that m_in gets overwritten during core
dumping.*

To work around this problem VFS now uses a so called "scratchpad" to
store temporary data that has to be globally accessible. This is a simple
table indexed by process number, just like fproc. The scratchpad allows
us to store the buffer pointer and buffer size for suspended system calls
(i.e., read, write, open, lock) instead of using fproc. This makes fproc
a bit smaller and fproc iterators a bit faster. Moreover, suspension of
processes becomes simpler altogether and suspended operations on pipes
are now less of a special case.

* This patch fixes a bug where due to unexpected m_in overwriting a
coredump would fail, and consequently resources are leaked. The coredump
was triggered with:
$ a() { a; }
$ a
2011-12-21 10:52:51 +00:00
Thomas Veerman
54c0eb9aa6 Compare read/write buf size against SSIZE_MAX instead of "< 0"
The nbyte in read(int fildes, void *buf, size_t nbyte) is unsigned,
so although technically we're doing the same comparison, this is more
in line with POSIX.

The comparison was moved to read_write as that routine is used within
VFS to let it VFS write out coredumps.
2011-12-21 10:46:09 +00:00
Thomas Veerman
9f9f893123 Mark filp as in use on fd dup'ing 2011-12-21 10:45:29 +00:00
Thomas Veerman
94da86cbee Discard process' pending request upon incoming PM request
When a process wants something done from VFS, but VFS has no worker
threads available, the request is stored and executed later. However,
when PM also sends a request for that process at the same time, discard
the pending request from the process and give priority to PM. The request
PM sends is either an EXIT or a DUMPCORE request, so we're not interested
in executing the pending request anyway.
2011-12-12 08:20:35 +00:00
David van Moolenbroek
6f374faca5 Add "expected size" parameter to getsysinfo()
This patch provides basic protection against damage resulting from
differently compiled servers blindly copying tables to one another.
In every getsysinfo() call, the caller is provided with the expected
size of the requested data structure. The callee fails the call if
the expected size does not match the data structure's actual size.
2011-12-11 22:34:14 +01:00
David van Moolenbroek
9701e9dfd2 Servers: cleanup of some gcc -W warnings 2011-12-11 22:33:37 +01:00
Thomas Veerman
26d359a30c Properly unlock on mount failure 2011-12-09 15:47:42 +00:00
Thomas Veerman
5cbbfc69e7 Change asserts with side effects into panics 2011-12-09 14:46:10 +00:00
Thomas Veerman
706873142e Fix dangling symlink resolving for AVFS and add test61 2011-12-09 10:34:23 +00:00
Thomas Veerman
0a61519eea Provide core dumping support for AVFS 2011-12-08 10:47:11 +00:00
David van Moolenbroek
9221586f37 vfs/avfs: req_newdriver should use fs_sendrec
Using sendrec directly only results in problems. While it is not
clear whether using fs_sendrec is the best option, it is at least
an improvement.

Also remove some legacy cruft.
2011-12-05 16:28:09 +01:00
David van Moolenbroek
db087efac4 VFS/FS: REQ_NEW_DRIVER now provides a label 2011-11-30 19:05:26 +01:00
Thomas Veerman
b4fb061802 Implement issetugid syscall
Implement issetugid syscall and provide a test. This gets rid of the
scary "Unsecure. Implement me" warning during compilation.
2011-11-28 10:03:43 +00:00
David van Moolenbroek
a9f89a7290 vfs/avfs: map O_ACCMODE to R_BIT|W_BIT on recovery 2011-11-24 13:57:36 +01:00
David van Moolenbroek
e8f944d3ca avfs: unbreak process termination on PM_DUMPCORE 2011-11-24 13:04:52 +01:00
David van Moolenbroek
b4d909d415 Split block/character protocols and libdriver
This patch separates the character and block driver communication
protocols. The old character protocol remains the same, but a new
block protocol is introduced. The libdriver library is replaced by
two new libraries: libchardriver and libblockdriver. Their exposed
API, and drivers that use them, have been updated accordingly.
Together, libbdev and libblockdriver now completely abstract away
the message format used by the block protocol. As the memory driver
is both a character and a block device driver, it now implements its
own message loop.

The most important semantic change made to the block protocol is that
it is no longer possible to return both partial results and an error
for a single transfer. This simplifies the interaction between the
caller and the driver, as the I/O vector no longer needs to be copied
back. Also, drivers are now no longer supposed to decide based on the
layout of the I/O vector when a transfer should be cut short. Put
simply, transfers are now supposed to either succeed completely, or
result in an error.

After this patch, the state of the various pieces is as follows:
- block protocol: stable
- libbdev API: stable for synchronous communication
- libblockdriver API: needs slight revision (the drvlib/partition API
  in particular; the threading API will also change shortly)
- character protocol: needs cleanup
- libchardriver API: needs cleanup accordingly
- driver restarts: largely unsupported until endpoint changes are
  reintroduced

As a side effect, this patch eliminates several bugs, hacks, and gcc
-Wall and -W warnings all over the place. It probably introduces a
few new ones, too.

Update warning: this patch changes the protocol between MFS and disk
drivers, so in order to use old/new images, the MFS from the ramdisk
must be used to mount all file systems.
2011-11-23 14:06:37 +01:00
David van Moolenbroek
0bb27bb0b1 Servers: remove ABI comment 2011-11-07 22:24:59 +01:00
David van Moolenbroek
b02c260ecb Miscellaneous legacy cleanup 2011-11-07 22:20:55 +01:00
Thomas Veerman
65e54c23e3 PFS is also a system proc 2011-10-28 12:49:47 +00:00
Thomas Veerman
febb4403ff Reenable backcall detection 2011-10-27 15:29:37 +00:00
Thomas Veerman
823e42c3e3 Make AVFS deal intelligently with back calling FSes
PUFFS file systems need to make back calls for every operation we
send to them. Consequently, they cannot handle block reads and writes
themselves. Instead, the root file system has to do it (for now).

When the mount operation causes an FS to make a back call, AVFS now
concludes that every block read and write for that FS has to go
through the root file system.
2011-10-27 15:29:23 +00:00
Thomas Veerman
9e21d55e37 err_code has to be preserved as well. Short term fix 2011-10-25 12:12:20 +00:00
Thomas Veerman
90cde23c19 Cleanup more resources upon exit 2011-09-16 10:16:57 +00:00
Thomas Veerman
1c928cf61a Remove debug print 2011-09-16 10:16:32 +00:00
Thomas Veerman
200b9d7339 Unmap drivers upon exit 2011-09-16 10:16:00 +00:00
Thomas Veerman
203937456e Fix off-by-one errors and increase PATH_MAX to 1024
In some places it was assumed that PATH_MAX does not include a
terminating null character.

Increases PATH_MAX to 1024 to get in sync with NetBSD. Required some
rewriting in AVFS to keep memory usage low (the stack in use by a thread
is very small).
2011-09-12 09:00:24 +00:00
Thomas Veerman
d4b72e81b2 Cleanup servers to make GCC/Clang a little happier 2011-09-08 13:57:03 +00:00
Thomas Veerman
7db039347a Make AVFS resilient against failing back calls 2011-09-06 10:38:16 +00:00
Thomas Veerman
8a266a478e Increase gid_t and uid_t to 32 bits
Increase gid_t and uid_t to 32 bits and provide backwards compatibility
where needed.
2011-09-05 13:56:14 +00:00
Thomas Veerman
7f24c2b3ca Unverbose mount 2011-08-26 15:49:37 +00:00
Thomas Veerman
78183bddff Let FSes exit themselves upon system shutdown
During shutdown all processes are semi-exited and FSes are unmounted.
This semi-exit causes trouble for FUSE mounts as they still need access
to file descriptors and working directory in order to unmount.
2011-08-26 15:17:53 +00:00
Thomas Veerman
30be017762 Store and use max concurrent requests 2011-08-26 12:47:43 +00:00
Thomas Veerman
e09714ab53 Turn off block read debugs and turn on mount debugs 2011-08-22 13:24:35 +00:00
Thomas Veerman
4ee157f5ce Report error instead panicing 2011-08-22 13:08:38 +00:00
Thomas Veerman
1f28a4b83e Remove verbosity 2011-08-22 13:08:03 +00:00