On Linux, /proc/<pid>/fd is comparable to fdescfs, where it allows you
to inspect the file descriptors used by each process. Glibc's ttyname()
works by performing a readlink() on these nodes, since all nodes in this
directory are symlinks.
It is a bit hard to implement this in linprocfs right now, so I am not
going to bother. Add a way to make ttyname(3) work, by adding a
/proc/<pid>/fd symlink, which points to /dev/fd only if the calling
process matches. When fdescfs is mounted, this will cause the
readlink() in ttyname() to fail, causing it to fall back on manually
finding a matching node in /dev.
Discussed on: emulation@
this matches the Linux behavior.
- Check if we have sufficient space allocated for socket structure, which
fixes a buffer overflow when wrong length is being passed into the
emulation layer. [1]
PR: kern/138860
Submitted by: Mateusz Guzik <mjguzik gmail com>
Reported by: Alexander Best [1]
MFC after: 2 weeks
With this change, Linux binaries can work with our libusb(3) when
it's compiled against our header files on GNU/Linux system -- this
solves the problem with differences between /dev layouts.
With ported libusb(3), I am able to use my USB JTAG cable with Linux
binaries that support it.
Reviewed by: thompsa
---snip---
Add video clipping support but with the caveats below.
Background info:
Video clipping allows the user to provide either a series of clip rectangles
or a clip bitmap to the driver and have the driver mask the video according
to the clipping specs provided.
Adding support for clipping to the FreeBSD Linux emulator is problematic
because it seems that this feature is not supported by many drivers and
therefore it is ignored by many applications. Unfortunately, when not
using it, rather than passing in a null clipping list, some apps leave the
clipping fields uninitialized, casuing random values to be passed in. In
the case where the driver does not use the clipping info, this is not a
problem (although it is bad form). But the Linux emulator does not know
which drivers will use this and which won't, so the Linux emulator must
try to handle this clip list, and deal gracefully with cases where the
values seem to be uninitialized.
Video clipping info is passed in using the VIDIOCSWIN ioctl in two fields
in the video_window structure: the integer clipcount and the pointer clips.
How the linuxulator handles this from this commit on:
* if (clipcount == VIDEO_CLIP_BITMAP)
The clips variable is a void * pointer to a 128*625 byte
(1024*625 bit) memory area containing a bitmap of the clipping area.
The pointer in the video_window structure is copied, but no
video_clip structures are copied.
* if (clipcount > 0 && clipcount <= 16384)
The clips variable is pointer to a list of video_clip structures. Up
to clipcount structures are copied and passed to the driver.
The upper limit of 16384 was imposed here so that user code that does
not properly initialize clipcount falls through below and no attempt
is made to copy an uninitialized list. This value was found by
examining Linux drivers that support the clip list.
* else
The clipcount is either negative (but not VIDEO_CLIP_BITMAP), zero or
positive (> 16384).
All these cases are treated as invalid data. Both the clipcount field
and clips pointer are forced to zero/NULL and passed to the driver.
It should be noted that, at the time of developing this V4L emulator code,
the pwc(4) V4L driver does not support clipping.
Submitted by: J.R. Oldroyd <fbsd@opal.com>
MFC after: 1 month
---snip---
native devices which support the v4l API from processes running within
the linuxulator, e.g. skype or flash can access the multimedia/pwcbsd driver.
Not tested is firmware upload, framebuffer stuff and video tuner stuff
due to lack of hardware.
The clipping part (VIDIOCSWIN) needs a little bit of further work (partly
in progress, but can not be tested due to lack of a suitable device).
The submitter tested this sucessfully with Skype and flash apps on amd64 and
i386 with the multimedia/pwcbsd driver.
Submitted by: J.R. Oldroyd <fbsd@opal.com>
kern.ngroups+1. kern.ngroups can range from NGROUPS_MAX=1023 to
INT_MAX-1. Given that the Windows group limit is 1024, this range
should be sufficient for most applications.
MFC after: 1 month
When renaming a directory it passes through several intermediate
states. First its new name will be created causing it to have two
names (from possibly different parents). Next, if it has different
parents, its value of ".." will be changed from pointing to the old
parent to pointing to the new parent. Concurrently, its old name
will be removed bringing it back into a consistent state. When fsck
encounters an extra name for a directory, it offers to remove the
"extraneous hard link"; when it finds that the names have been
changed but the update to ".." has not happened, it offers to rewrite
".." to point at the correct parent. Both of these changes were
considered unexpected so would cause fsck in preen mode or fsck in
background mode to fail with the need to run fsck manually to fix
these problems. Fsck running in preen mode or background mode now
corrects these expected inconsistencies that arise during directory
rename. The functionality added with this update is used by fsck
running in background mode to make these fixes.
Solution:
This update adds three new fsck sysctl commands to support background
fsck in correcting expected inconsistencies that arise from incomplete
directory rename operations. They are:
setcwd(dirinode) - set the current directory to dirinode in the
filesystem associated with the snapshot.
setdotdot(oldvalue, newvalue) - Verify that the inode number for ".."
in the current directory is oldvalue then change it to newvalue.
unlink(nameptr, oldvalue) - Verify that the inode number associated
with nameptr in the current directory is oldvalue then unlink it.
As with all other fsck sysctls, these new ones may only be used by
processes with appropriate priviledge.
Reported by: jeff
Security issues: rwatson
target one. Since r184058, linux_do_tkill() calls tdsignal() instead of
kill(), without checking for validity of supplied signal number. Prevent
panic when supplied signal is 0 by finishing work after checks.
Found and tested by: scf
MFC after: 3 days
native devices which support the v4l API from processes running within
the linuxulator, e.g. skype or flash can access the multimedia/pwcbsd driver.
Not tested is firmware upload, framebuffer stuff and video tuner stuff
due to lack of hardware.
The clipping part (VIDIOCSWIN) needs a little bit of further work (partly
in progress, but can not be tested due to lack of a suitable device).
The submitter tested this sucessfully with Skype and flash apps on amd64 and
i386 with the multimedia/pwcbsd driver.
Submitted by: J.R. Oldroyd <fbsd@opal.com>
Right now <sys/termios.h> includes <sys/ttycom.h>, which provides the
TTY ioctls to the svr4 code. We need both struct termios and the ioctls,
so include <sys/tty.h> for now.
well-known race condition, which elimination was the reason for the
function appearance in first place. If sigmask supplied as argument to
pselect() enables a signal, the signal might be delivered before thread
called select(2), causing lost wakeup. Reimplement pselect() in kernel,
making change of sigmask and sleep atomic.
Since signal shall be delivered to the usermode, but sigmask restored,
set TDP_OLDMASK and save old mask in td_oldsigmask. The TDP_OLDMASK
should be cleared by ast() in case signal was not gelivered during
syscall execution.
Reviewed by: davidxu
Tested by: pho
MFC after: 1 month
while in kernel mode, and later changing signal mask to block the
signal, was fixed for sigprocmask(2) and ptread_exit(3). The same race
exists for sigreturn(2), setcontext(2) and swapcontext(2) syscalls.
Use kern_sigprocmask() instead of direct manipulation of td_sigmask to
reschedule newly blocked signals, closing the race.
Reviewed by: davidxu
Tested by: pho
MFC after: 1 month
kern_sigprocmask() to properly notify other possible candidate threads
for signal delivery.
Since sigsuspend() shall only return to usermode after a signal was
delivered, do cursig/postsig loop immediately after waiting for
signal, repeating the wait if wakeup was spurious due to race with
other thread fetching signal from the process queue before us. Add
thread_suspend_check() call to allow the thread to be stopped or killed
while in loop.
Modify last argument of kern_sigprocmask() from boolean to flags,
allowing the function to be called with locked proc. Convertion of the
callers that supplied 1 to the old argument will be done in the next
commit, and due to SIGPROCMASK_OLD value equial to 1, code is formally
correct in between.
Reviewed by: davidxu
Tested by: pho
MFC after: 1 month
no matter whether we are compiled as module or if our default of the
net.inet6.ip6.v6only sysctl already matches what we would set.
This avoids unnecessary complications with modules, VIMAGES, INET6 and
the sysctl value, especially considering that most users will use
linux compat as a module.
Discussed with: kib, rwatson (weeks ago)
Reviewed by: rwatson
MFC after: 6 weeks
- Do not map entire real mode memory (1MB). Instead, we map IVT/BDA and
ROM area separately. Most notably, ROM area is mapped as device memory
(uncacheable) as it should be. User memory is dynamically allocated and
free'ed with contigmalloc(9) and contigfree(9). Remove now redundant and
potentially dangerous x86bios_alloc.c. If this emulator ever grows to
support non-PC hardware, we may implement it with rman(9) later.
- Move all host-specific initializations from x86emu_util.c to x86bios.c and
remove now unnecessary x86emu_util.c. Currently, non-PC hardware is not
supported. We may use bus_space(9) later when the KPI is fixed.
- Replace all bzero() calls for emulated registers with more obviously named
x86bios_init_regs(). This function also initializes DS and SS properly.
- Add x86bios_get_intr(). This function checks if the interrupt vector is
available for the platform. It is not necessary for PC-compatible hardware
but it may be needed later. ;-)
- Do not try turning off monitor if DPMS does not support the state.
- Allocate stable memory for VESA OEM strings instead of just holding
pointers to them. They may or may not be accessible always. Fix a memory
leak of video mode table while I am here.
- Add (experimental) BIOS POST call for vesa(4). This function calls VGA
BIOS POST code from the current VGA option ROM. Some video controllers
cannot save and restore the state properly even if it is claimed to be
supported. Usually the symptom is blank display after resuming from suspend
state. If the video mode does not match the previous mode after restoring,
we try BIOS POST and force the known good initial state. Some magic was
taken from NetBSD (and it was taken from vbetool, I believe.)
- Add a loader tunable for vgapci(4) to give a hint to dpms(4) and vesa(4)
to identify who owns the VESA BIOS. This is very useful for multi-display
adapter setup. By default, the POST video controller is automatically
probed and the tunable "hw.pci.default_vgapci_unit" is set to corresponding
vgapci unit number. You may override it from loader but it is very unlikely
to be necessary. Unfortunately only AGP/PCI/PCI-E controllers can be
matched because ISA controller does not have necessary device IDs.
- Fix a long standing bug in state save/restore function. The state buffer
pointer should be ES:BX, not ES:DI according to VBE 3.0. If it ever worked,
that's because BX was always zero. :-)
- Clean up register initializations more clearer per VBE 3.0.
- Fix a lot of style issues with vesa(4).
first and the native ia32 compat as middle (before other things).
o(ld)brandinfo as well as third party like linux, kfreebsd, etc.
stays on SI_ORDER_ANY coming last.
The reason for this is only to make sure that even in case we would
overflow the MAX_BRANDS sized array, the native FreeBSD brandinfo
would still be there and the system would be operational.
Reviewed by: kib
MFC after: 1 month
- Remove CS and IP registers from x86bios.h. They have no use for us.
- Adjust register dump to make it little bit more useful for debugging.
Submitted by: paradox (ddkprog yahoo com)[1] (initial version)
FreeBSD 8, the compatibility shims should be built not just when FreeBSD 7
compatibility is requested, but also when compatibility with any older
FreeBSD version where that feature was present is requested.o
Without this patch, a kernel config that sets COMPAT_FREEBSD6 but not *7
would fail to build due to inconsistencies between the declaration of the
compatibility shims and their use in the SysV code.
There are similar errors in other *proto.h headers in the tree.
MFC after: 3 weeks
longs. Since 32bit processes longs are 4 bytes, 64bit kernel may copy in
or out 4 bytes more then the process expected.
Calculate the amount of bytes to copy taking into account size of fd_set
for the current process ABI.
Diagnosed and tested by: Peter Jeremy <peterjeremy acm org>
Reviewed by: jhb
MFC after: 1 week
correctly and do not match a colliding Debian GNU/kFreeBSD
brandinfo statements.
For this mark the Debian GNU/kFreeBSD brandinfo that it must have
an .note.ABI-tag section and ignore the old EI_OSABI brandinfo
when comparing a possibly colliding set of options.
Due to SYSINIT we add the brandinfo in a non-deterministic order,
so native FreeBSD is not always first. We may want to consider
to force native FreeBSD to come first as well.
The only way a problem could currently be noticed is when running an
i386 binary without the .note.ABI-tag on amd64 and the Debian GNU/kFreeBSD
brandinfo was matched first, as the fallback to ld-elf32.so.1 does
not exist in that case.
Reported and tested by: ticso
In collaboration with: kib
MFC after: 3 days
Handle GNU/Linux according to LSB Core Specification 4.0,
Chapter 11. Object Format, 11.8. ABI note tag.
Also check the first word of desc, not only name, according to
glibc abi-tags specification to distinguish between Linux and
kFreeBSD.
Add explicit handling for Debian GNU/kFreeBSD, which runs
on our kernels as well [2].
In {amd64,i386}/trap.c, when checking osrel of the current process,
also check the ABI to not change the signal behaviour for Linux
binary processes, now that we save an osrel version for all three
from the lists above in struct proc [2].
These changes make it possible to run FreeBSD, Debian GNU/kFreeBSD
and Linux binaries on the same machine again for at least i386 and
amd64, and no longer break kFreeBSD which was detected as GNU(/Linux).
PR: kern/135468
Submitted by: dchagin [1] (initial patch)
Suggested by: kib [2]
Tested by: Petr Salinger (Petr.Salinger seznam.cz) for kFreeBSD
Reviewed by: kib
MFC after: 3 days
several critical bugs, including race conditions and lock order issues:
Replace the single rwlock, ifnet_lock, with two locks, an rwlock and an
sxlock. Either can be held to stablize the lists and indexes, but both
are required to write. This allows the list to be held stable in both
network interrupt contexts and sleepable user threads across sleeping
memory allocations or device driver interactions. As before, writes to
the interface list must occur from sleepable contexts.
Reviewed by: bz, julian
MFC after: 3 days
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks. Minor cleanups are done in the process,
and comments updated to reflect these changes.
Reviewed by: bz
Approved by: re (vimage blanket)
old ABI versions of the relevant control system call (e.g.
freebsd7_freebsd32_msgctl() instead of freebsd32_msgctl() for msgsys()).
Approved by: re (kib)
