result in errors for a format loading but subsequent correct recognizing
for another format.
File format loading functions should avoid printing any additional
informations but just returning appropriate (and different between each
other) error condition, characterizing different informations.
Additively, the linker should handle appropriately different format
loading errors.
While a general mechanism is desired, fix a simple and common case on
amd64: file type is not recognized for link elf and confuses the linker.
Printout an error if all the registered linker classes can't recognize
and load the module.
Reviewed by: jhb
Sponsored by: Sandvine Incorporated
vnode lock may cause a LOR between kld_sx lock and vnode lock.
linker_load_dependencies() drops kld_sx, and another thread may attempt
to load the same kld.
Reported and tested by: pjd
MFC after: 1 week
the elf files. This is complicated by the fact that the actual CTF
parsing has to be done in CDDL'd code, so the BSD licensed code only
knows about the opaque data which it must be able to free.
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.
KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.
Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:
mac_<object>_<method/action>
mac_<object>_check_<method/action>
The previous naming scheme was inconsistent and mostly
reversed from the new scheme. Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier. Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods. Also simplify, slightly,
some entry point names.
All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.
Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer
Change the VOP_OPEN(), vn_open() vnode operation and d_fdopen() cdev operation
argument from being file descriptor index into the pointer to struct file.
Proposed and reviewed by: jhb
Reviewed by: daichi (unionfs)
Approved by: re (kensmith)
__stop_<section> symbols generated by the static linker for elf
sections. This is done only for the final link, and not for ld -r.
Augment elf_obj in-kernel linker by recognizing such special symbols,
and resolving them to the start and end of the section automatically.
As result, linker sets on amd64 could be used in the same way as on
other architectures, without explicit calls to linker_file_lookup_set().
Requested by: rdivacky
No objections from: peter, jhb
begun with a repo-copy of mac.h to mac_framework.h. sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.
This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.
Obtained from: TrustedBSD Project
Sponsored by: SPARTA
protect all linker-related data structures including the contents of
linker file objects and the any linker class data as well. Considering how
rarely the linker is used I just went with the simple solution of
single-threading the whole thing rather than expending a lot of effor on
something more fine-grained and complex. Giant is still explicitly
acquired while registering and deregistering sysctl's as well as in the
elf linker class while calling kmupetext(). The rest of the linker runs
without Giant unless it has to acquire Giant while loading files from a
non-MPSAFE filesystem.
means:
o Remove Elf64_Quarter,
o Redefine Elf64_Half to be 16-bit,
o Redefine Elf64_Word to be 32-bit,
o Add Elf64_Xword and Elf64_Sxword for 64-bit entities,
o Use Elf_Size in MI code to abstract the difference between
Elf32_Word and Elf64_Word.
o Add Elf_Ssize as the signed counterpart of Elf_Size.
MFC after: 2 weeks
Add a MOD_QUIESCE event for modules. This should return error (EBUSY)
of the module is in use.
MOD_UNLOAD should now only fail if it is impossible (as opposed to
inconvenient) to unload the module. Valid reasons are memory references
into the module which cannot be tracked down and eliminated.
When kldunloading, we abandon if MOD_UNLOAD fails, and if -force is
not given, MOD_QUIESCE failing will also prevent the unload.
For backwards compatibility, we treat EOPNOTSUPP from MOD_QUIESCE as
success.
Document that modules should return EOPNOTSUPP for unknown events.
other modules to explode. eg: snd_ich->snd_pcm and umass->usb.
The problem was that I was using the unified base address of the module
instead of finding the start address of the section in question.
(nobits) tables to simplify some code. Try and shorten some of the very
wide lines. Somewhere along the way, I think I fixed the memory
corruption that caused panics after going multiuser.
as dependent on binutils features/quirks as the current one. This one
loads plain .o files without having to mess with shared object mode.
This happens to be essential on amd64, because binutils hasn't implemented
all the quirks/features that we need for producing the hack non-PIC shared
objects. As it turned out, .o format isn't all that inconvenient after
all. It looks like the ability to use the same .o files for linking
directly into a static kernel or loading as a module might be worth it.
It is still very much a work-in-progress, but it is almost usable. Other
changes are still needed in order to use it though, these have not been
committed yet. There is still a memory corruption/overrun bug somewhere.
For example, test modules load and work, but the machine explodes a few
minutes later in vm_forkproc() or the like. Notable missing things
include kldxref support, and loader(8) support. I wanted to figure out
a working baseline set of code first.
- All those diffs to syscalls.master for each architecture *are*
necessary. This needed clarification; the stub code generation for
mlockall() was disabled, which would prevent applications from
linking to this API (suggested by mux)
- Giant has been quoshed. It is no longer held by the code, as
the required locking has been pushed down within vm_map.c.
- Callers must specify VM_MAP_WIRE_HOLESOK or VM_MAP_WIRE_NOHOLES
to express their intention explicitly.
- Inspected at the vmstat, top and vm pager sysctl stats level.
Paging-in activity is occurring correctly, using a test harness.
- The RES size for a process may appear to be greater than its SIZE.
This is believed to be due to mappings of the same shared library
page being wired twice. Further exploration is needed.
- Believed to back out of allocations and locks correctly
(tested with WITNESS, MUTEX_PROFILING, INVARIANTS and DIAGNOSTIC).
PR: kern/43426, standards/54223
Reviewed by: jake, alc
Approved by: jake (mentor)
MFC after: 2 weeks
metadata. This fixes module dependency resolution by the kernel linker on
sparc64, where the relocations for the metadata are different than on other
architectures; the relative offset is in the addend of an Elf_Rela record
instead of the original value of the location being patched.
Also fix printf formats in debug code.
Submitted by: Hartmut Brandt <brandt@fokus.gmd.de>
PR: 46732
Tested on: alpha (obrien), i386, sparc64
checks permit policy modules to augment the system policy for permitting
kld operations. This permits policies to limit access to kld operations
based on credential (and other) properties, as well as to perform checks
on the kld being loaded (integrity, etc).
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
The primary reason for this is to allow MD code to process machine
specific attributes, segments or sections in the ELF file and
update machine specific state accordingly. An immediate use of this
is in the ia64 port where unwind information is updated to allow
debugging and tracing in/across modules. Note that this commit
does not add the functionality to the ia64 port. See revision 1.9
of ia64/ia64/elf_machdep.c.
Validated on: alpha, i386, ia64
link_elf_init(), link_elf_link_preload_finish() and
link_elf_load_file() to link_elf_link_common_finish().
Since link_elf_init() did initializations as a side-effect
of doing the common actions, keep the initialization in
that function. Consequently, link_elf_add_gdb() is now also
called to insert the very first link_map() (ie the kernel).
Move link_elf_add_gdb(), link_elf_delete_gdb() and link_elf_error()
near the top of the file. The *_gdb() functions are moved inside
the #ifdef DDB already present there.
cannot allocate ef->object, we freed ef before bailing out with
an error. This is wrong because ef=lf and when we have an error
and lf is non-NULL (which holds if we try to alloc ef->object),
we free lf and thus ef as part of the bailing-out.
were improperly relocated due to faulty logic in lookup_fdesc()
in elf_machdep.c. The symbol index (symidx) was bogusly used for
load modules other than the one the relocation applied to. This
resulted in bogus bindings and consequently runtime failures.
The fix is to use the symbol index only for the module being
relocated and to use the symbol name for look-ups in the
modules in the dependent list. As such, we need a function to
return the symbol name given the linker file and symbol index.
sparc v9 ABI. The Elf_Rela records for local symbols appear to already
have the symbol's value added in to the addend field, even though the ABI
specifies we need to lookup the symbol and add its value too. This breaks
text relocations in klds because the symbol's value is added twice, and
the resulting address points off into nowhere land, so for now just use
the addend.
Tested by: rwatson
under way to move the remnants of the a.out toolchain to ports. As the
comment in src/Makefile said, this stuff is deprecated and one should not
expect this to remain beyond 4.0-REL. It has already lasted WAY beyond
that.
Notable exceptions:
gcc - I have not touched the a.out generation stuff there.
ldd/ldconfig - still have some code to interface with a.out rtld.
old as/ld/etc - I have not removed these yet, pending their move to ports.
some includes - necessary for ldd/ldconfig for now.
Tested on: i386 (extensively), alpha
a pointer to a symbol is given and we have to find the containing symbol
table. We do this by bounds checking. For some strange reason (ie I
haven't found the root cause) the first test succeeded for said symbol,
implying that the symbol came from the .dynsym table. In reality however
the symbol actually resided in the .symtab table. Needless to say that
all that was returned was junk.
The upper bounds check was: (symptr - baseptr) < symtab_size
This has been rewritten to: symptr < (baseptr + symtab_size)
As a side-effect, slightly more optimal (and still correct :-) code can
be generated on ia64.
make a series of modifications to the credential arguments relating
to file read and write operations to cliarfy which credential is
used for what:
- Change fo_read() and fo_write() to accept "active_cred" instead of
"cred", and change the semantics of consumers of fo_read() and
fo_write() to pass the active credential of the thread requesting
an operation rather than the cached file cred. The cached file
cred is still available in fo_read() and fo_write() consumers
via fp->f_cred. These changes largely in sys_generic.c.
For each implementation of fo_read() and fo_write(), update cred
usage to reflect this change and maintain current semantics:
- badfo_readwrite() unchanged
- kqueue_read/write() unchanged
pipe_read/write() now authorize MAC using active_cred rather
than td->td_ucred
- soo_read/write() unchanged
- vn_read/write() now authorize MAC using active_cred but
VOP_READ/WRITE() with fp->f_cred
Modify vn_rdwr() to accept two credential arguments instead of a
single credential: active_cred and file_cred. Use active_cred
for MAC authorization, and select a credential for use in
VOP_READ/WRITE() based on whether file_cred is NULL or not. If
file_cred is provided, authorize the VOP using that cred,
otherwise the active credential, matching current semantics.
Modify current vn_rdwr() consumers to pass a file_cred if used
in the context of a struct file, and to always pass active_cred.
When vn_rdwr() is used without a file_cred, pass NOCRED.
These changes should maintain current semantics for read/write,
but avoid a redundant passing of fp->f_cred, as well as making
it more clear what the origin of each credential is in file
descriptor read/write operations.
Follow-up commits will make similar changes to other file descriptor
operations, and modify the MAC framework to pass both credentials
to MAC policy modules so they can implement either semantic for
revocation.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
the symbol index defined by the relocation. The elf_lookup() support
function is to be used by elf_reloc() when symbol lookups need to be
done. The elf_lookup() function operates on the symbol index and
will do a symbol name based lookup when such is required, otherwise
it uses the symbol index directly. This solves the problem seen on
ia64 where the symbol hash table does not contain local symbols and
a symbol name based lookup would fail for those symbols.
Don't pass the symbol name to elf_reloc(), as it isn't used any more.
the DT_PLTGOT value. On ia64 this is the value of GP. We need this
to construct function descriptors, but the elf file structure is
not exported to MD code.
Note that the name of the function is based on the meaning that
DT_PLTGOT has on ia64. This may differ on other architectures. As
such, link_elf_get_gp() has a high level of MD to it. Renaming the
function to describe what DT_* value is returned makes it generic,
but also makes the MD code less clear and if we only need this on
ia64, then a general name for a specific function doesn't help.
In short: I don't know what is "right" at this time, so I'll go
with what I have.
function symbols in the kernel in a list of C strings, with an extra
nul-termination at the end.
This sysctl requires addition of a new linker operation. Now,
linker_file_t's need to respond to "each_function_name" to export
their function symbols.
Note that the sysctl doesn't currently allow distinguishing multiple
symbols with the same name from different modules, but could quite
easily without a change to the linker operation. This will be a nicety
to have when it can be used.
Obtained from: NAI Labs CBOSS project
Funded by: DARPA
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
and I still dont know why, this was not failing on the non-kse kernel.
It certainly should have since things were using linker_kernel_file
unconditionally. This has highlighted a different problem though that
means that trying to do a kldload on a non-dynamic kernel will implode.
structure is always free()ed yet only sometimes malloc()ed. In particular,
it was simply set to point to l_filename from the a linker_file_t in
link_elf_link_preload_finish(). The l_filename had been malloc()ed inside
the kern_linker.c module and was being free()ed twice: once by
link_elf_unload_file() and again by linker_file_unload(), leading to
a panic.
How to duplicate the problem:
- Pre-load a kernel module from the loader, i.e. if_sis.ko
- Boot system
- Attempt to unload module with kldunload if_sis
- Bewm
The problem here is that the case where the module was loaded with kldload
after system boot would work correctly, so this bug went unnoticed until
I stubbed my toe on it just now. (Also, you can only trip this bug if
you compile a kernel with options DDB, but that's the default now.)
Fix: remember to malloc() a separate copy of the module name for the
l_name member of the gdb linkage structure in three places where the
linkage structure can be initialized.
filename passed in via the module loader functions in the GDB
"sharedlibrary" support structures. This isn't good, since the pointer
would become stale in almost every case (not the pre-loaded case, of
course).
Change this to malloc()ed copy of the string and finally fix the reason
that gdb -k's "sharedlibrary" command stopped working.
Obtained from: LOMAC/FreeBSD (cf. NAI Labs)
dynamic symbol table buckets and chains. The sparc64 toolchain uses 32
bit .hash entries, unlike other 64 bits architectures (alpha), which use
64 bit entries.
Discussed with: dfr, jdp
(this commit is just the first stage). Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
Replace the a.out emulation of 'struct linker_set' with something
a little more flexible. <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.
The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).
The macros declare a strongly typed set. They return elements with the
type that you declare the set with, rather than a generic void *.
For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>). Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.
For a.out, we use the old linker_set struct.
NOTE: the item lists are no longer null terminated. This is why
the code impact is high in certain areas.
The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.
linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.
Reviewed by: eivind
vm_mtx does not recurse and is required for most low level
vm operations.
faults can not be taken without holding Giant.
Memory subsystems can now call the base page allocators safely.
Almost all atomic ops were removed as they are covered under the
vm mutex.
Alpha and ia64 now need to catch up to i386's trap handlers.
FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).
Reviewed (partially) by: jake, jhb
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
a breakpoint in the kernel didn't use the proper argument list. To avoid
having to include the userland link.h header everyhwere that sys/linker.h
is used, make r_debug_state() a static function in link_elf.c as well.
after the acquisition of any advisory locks. This fix corrects a case
in which a process tries to open a file with a non-blocking exclusive
lock. Even if it fails to get the lock it would still truncate the
file even though its open failed. With this change, the truncation
is done only after the lock is successfully acquired.
Obtained from: BSD/OS
version dependency system. This isn't quite finished, but it is at a
useful stage to do a functional checkpoint.
Highlights:
- version and dependency metadata is gathered via linker sets, so things
are handled the same for static kernels and code built to live in a kld.
- The dependencies are at module level (versus at file level).
- Dependencies determine kld symbol search order - this means that you
cannot link against symbols in another file unless you depend on it. This
is so that you cannot accidently unload the target out from underneath
the ones referencing it.
- It is flexible enough that we can put tags in #include files and macros
so that we can get decent hooks for enforcing recompiles on incompatable
ABI changes. eg: if we change struct proc, we could force a recompile
for all kld's that reference the proc struct.
- Tangled dependency references at boot time are sorted. Files are
relocated once all their dependencies are already relocated.
Caveats:
- Loader support is incomplete, but has been worked on seperately.
- Actual enforcement of the version number tags is not active yet - just
the module dependencies are live. The actual structure of versioning
hasn't been agreed on yet. (eg: major.minor, or whatever)
- There is some backwards compatability for old modules without metadata
but I'm not sure how good it is.
This is based on work originally done by Boris Popov (bp@freebsd.org),
but I'm not sure he'd recognize much of it now. Don't blame him. :-)
Also, ideas have been borrowed from Mike Smith.
* Report link errors to stdout with uprintf() so that the user can see
what went wrong (PR kern/9214).
* Add support code to allow module symbols to be loaded into GDB using
the debugger's "sharedlibrary" command.
Merge the contents (less some trivial bordering the silly comments)
of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>. This puts
the #defines for the vm_inherit_t and vm_prot_t types next to their
typedefs.
This paves the road for the commit to follow shortly: change
useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE}
as argument.
terminating c_caddr_t with extreme prejudice. Here we depended
on the "opaque" type c_caddr_t being precisely `const char *'
to do unportable pointer arithmetic.
we can recurse when loading dependencies and that the kstack is limited
to something like 6 or 7KB. Having a single dependency caused an instant
double panic, and I stronly suspect some of the other strange "events"
that I have seen are possibly as a result of taking a couple of interrupts
with a large chunk of the stack already in use.
While here, fix a minor logic hiccup in a sanity check.
This is the bulk of the support for doing kld modules. Two linker_sets
were replaced by SYSINIT()'s. VFS's and exec handlers are self registered.
kld is now a superset of lkm. I have converted most of them, they will
follow as a seperate commit as samples.
This all still works as a static a.out kernel using LKM's.
