Guard, requested by the MAP_GUARD mmap(2) flag, prevents the reuse of
the allocated address space, but does not allow instantiation of the
pages in the range. It is useful for more explicit support for usual
two-stage reserve then commit allocators, since it prevents accidental
instantiation of the mapping, e.g. by mprotect(2).
Use guards to reimplement stack grow code. Explicitely track stack
grow area with the guard, including the stack guard page. On stack
grow, trivial shift of the guard map entry and stack map entry limits
makes the stack expansion. Move the code to detect stack grow and
call vm_map_growstack(), from vm_fault() into vm_map_lookup().
As result, it is impossible to get random mapping to occur in the
stack grow area, or to overlap the stack guard page.
Enable stack guard page by default.
Reviewed by: alc, markj
Man page update reviewed by: alc, bjk, emaste, markj, pho
Tested by: pho, Qualys
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D11306 (man pages)
The flag is not implemented, all FreeBSD architectures correctly
handle locks on normal cacheable mappings. On the other hand, the
flag was specified by some software, so it is kept in the header as
nop. Removal from the man page should discourage its use.
Reviewed by: alc, bjk, emaste, markj, pho
MFC after: 3 days
X-Differential revision: https://reviews.freebsd.org/D11306
Add forward compatibility so that new binaries can run on old
kernels. If the new system call from ino64 isn't available on your
system, then the old one will be used and the results translated. The
stat and statfs families of functions are fully emulated. While not
required by policy, in this case it is helpful to our users to provide
this compatibility. In this case, it allows rollback of the kernel
after installing a new userland should a problem be discovered. It
also prevents foot-shooting if a user does an install before rebooting
with the new kernel. Finally, it allows the use case where one needs
to run new binaries on an old kernel as part of an upgrade process.
The getdirentries family uses tricks that may not work on remote
filesystems. Specifically, it uses a buffer 1/4 the size requested to
get the data from he old syscall.
The code carefully uses direct syscalls for old system calls to avoid
referencing freebsd11_* symbols, which contaminate ld-elf.so.1's
export table due to its use of stat functions, which causes errno to
be incorrect in client programs due to the wrong *stat* function being
resolved in some cases.
This code should removed sometime after 12 is branched.
Tested on: 12-current binaries on a 10.3-beta kernel run and return
consistent results. 12-current kernel and userland with
packages from before ino64 was committed also work.
Differential Revision: https://reviews.freebsd.org/D11185
Reviewed by: kib@, emaste@
In r300388, endnetconfig() was called on nc_handle which would release
the associated netconfig structure, which means tmpnconf->nc_netid
would be a use-after-free.
Solve this by doing endnetconfig() in return paths instead.
Reported by: jemalloc via kevlo
Reviewed by: cem, ngie (earlier version)
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D11288
Replace conditional branches with trampolines to unconditional branches when
jumping to labels within other compilation units. This increases the offset
range from +-1 MiB to +-128 MiB.
This syscall has never existed and is not at risk of existing any time soon.
Remove documentation referencing it, which has been wrong since FreeBSD 9.
Reported by: allanjude@
Make syslog(3) resilent to cancellation occuring in supported deferred
mode. Code must unlock syslog_mutex on cancel, install the cleanup
handler.
Diagnosed and tested by: eugen
Discussed with: dchagin
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
This change implements NOTE_ABSTIME flag for EVFILT_TIMER, which
specifies that the data field contains absolute time to fire the
event.
To make this useful, data member of the struct kevent must be extended
to 64bit. Using the opportunity, I also added ext members. This
changes struct kevent almost to Apple struct kevent64, except I did
not changed type of ident and udata, the later would cause serious API
incompatibilities.
The type of ident was kept uintptr_t since EVFILT_AIO returns a
pointer in this field, and e.g. CHERI is sensitive to the type
(discussed with brooks, jhb).
Unlike Apple kevent64, symbol versioning allows us to claim ABI
compatibility and still name the new syscall kevent(2). Compat shims
are provided for both host native and compat32.
Requested by: bapt
Reviewed by: bapt, brooks, ngie (previous version)
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D11025
gets output via warnx(3)
This helps set expectations for how one might deal with those messages, i.e.,
mute output from /dev/stderr today, since that's where vwarn(3) outputs messages
to today.
MFC after: 1 month
The futimens() and utimensat() compat stubs allowed using these functions on
kernels that did not have the system calls yet (10.2, old 11-current).
Also remove the documentation of the [ENOTSUP] error that could occur with
an old kernel.
A -DNO_CLEAN build may fail because the depend files refer to the deleted
files.
The documentation moved to section 3 several years ago, but
'man cap_rights_get' pulls up cap_rights_limit(2) (which is
MLINKed to cap_rights_get.2) instead of cap_rights_get(3).
MFC after: 1 week
const char *.
This fixes a bogus set of errors from gcc about strdup not being allowed a NULL
argument.
MFC after: 1 week
Sponsored by: Dell EMC Isilon
- Fix -Wmissing-declaration warning by staticizing run_tests.
- Fix -Wsign-compare warnings by casting size_t types to int
for comparisons.
Reindent some of the code in sdump_hostent(..) to accomodate the
overall changes.
MFC after: 3 days
Sponsored by: Dell EMC Isilon
The pattern used prior to this commit was `calloc(1, n * sizeof(type))`;
the pattern that should be used however is `calloc(n, sizeof(type))`.
MFC after: 3 days
Sponsored by: Dell EMC Isilon
Move an unneeded initialization, introduced in r54770 to quiet down GCC,
to a place nearer to its first use. This has no practical effect, it just
keeps the garbage better sorted.
Hinted by: OpenBSD (CVS rev. 1.56, without obfuscations)