This allows an endless stream of random data within the given bounds.
It already worked if a seed was provided as the 4th argument but not
if one was left out.
In collaboration with: jhb
MFC after: 2 weeks
Relnotes: yes
This changes the sender mail address in a similar fashion to how MAILTO may
change the recipient. The default from address remains unchanged.
MFC after: 1 week
random.3 is only "better" in contrast to rand.3. Both are non-cryptographic
pseudo-random number generators. The opening blurbs of each's DESCRIPTION
section does emphasize this, and correctly directs unfamiliar developers to
arc4random(3). However, the summary (".Nd" or Name description) of random.3
conflicted in tone and message with that warning.
Resolve the conflict by clarifying in the Nd section that random(3) is
non-cryptographic and pseudo-random. Elide the "better" qualifier which
implied a comparison but did not provide a specific object to contrast.
Sponsored by: Dell EMC Isilon
read_random() is/was used, mostly without error checking, in a lot of
very sensitive places in the kernel -- including seeding the widely used
arc4random(9).
Most uses, especially arc4random(9), should block until the device is seeded
rather than proceeding with a bogus or empty seed. I did not spy any
obvious kernel consumers where blocking would be inappropriate (in the
sense that lack of entropy would be ok -- I did not investigate locking
angle thoroughly). In many instances, arc4random_buf(9) or that family
of APIs would be more appropriate anyway; that work was done in r345865.
A minor cleanup was made to the implementation of the READ_RANDOM function:
instead of using a variable-length array on the stack to temporarily store
all full random blocks sufficient to satisfy the requested 'len', only store
a single block on the stack. This has some benefit in terms of reducing
stack usage, reducing memcpy overhead and reducing devrandom output leakage
via the stack. Additionally, the stack block is now safely zeroed if it was
used.
One caveat of this change is that the kern.arandom sysctl no longer returns
zero bytes immediately if the random device is not seeded. This means that
FreeBSD-specific userspace applications which attempted to handle an
unseeded random device may be broken by this change. If such behavior is
needed, it can be replaced by the more portable getrandom(2) GRND_NONBLOCK
option.
On any typical FreeBSD system, entropy is persisted on read/write media and
used to seed the random device very early in boot, and blocking is never a
problem.
This change primarily impacts the behavior of /dev/random on embedded
systems with read-only media that do not configure "nodevice random". We
toggle the default from 'charge on blindly with no entropy' to 'block
indefinitely.' This default is safer, but may cause frustration. Embedded
system designers using FreeBSD have several options. The most obvious is to
plan to have a small writable NVRAM or NAND to persist entropy, like larger
systems. Early entropy can be fed from any loader, or by writing directly
to /dev/random during boot. Some embedded SoCs now provide a fast hardware
entropy source; this would also work for quickly seeding Fortuna. A 3rd
option would be creating an embedded-specific, more simplistic random
module, like that designed by DJB in [1] (this design still requires a small
rewritable media for forward secrecy). Finally, the least preferred option
might be "nodevice random", although I plan to remove this in a subsequent
revision.
To help developers emulate the behavior of these embedded systems on
ordinary workstations, the tunable kern.random.block_seeded_status was
added. When set to 1, it blocks the random device.
I attempted to document this change in random.4 and random.9 and ran into a
bunch of out-of-date or irrelevant or inaccurate content and ended up
rototilling those documents more than I intended to. Sorry. I think
they're in a better state now.
PR: 230875
Reviewed by: delphij, markm (earlier version)
Approved by: secteam(delphij), devrandom(markm)
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D19744
This allows efficient filtering at packet ingress on mlx5en.
Note that the packets are filtered (and potentially dropped) *before*
the driver has committed to (re)allocating an mbuf for the
packet. Dropped packets are treated essentially the same as an
error. Nothing is allocated, and the existing buffer is recycled. This
allows us to drop malicious packets at close to line rate with very
little CPU use.
Reviewed by: hselasky, slavash, kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D19063
The SPCR table on the Lenovo HR330A Ampere eMAG server indicates 8-bit
access, but 32-bit access is required for the PL011 to work.
PL011 on SBSA platforms always supports 32-bit access (and that was
hardcoded here before my EC2 fix), let's use 32-bit access for PL011
and 32BIT interface types.
Tested by emaste on Ampere eMAG and Cavium/Marvell ThunderX2.
Submitted by: Greg V <greg@unrelenting.technology>
Reviewed by: andrew, imp (earlier)
Differential Revision: https://reviews.freebsd.org/D19507
Since inits for the main binary are run from rtld (for some time), the
rtld_exit atexit(3) handler, which is passed from rtld to the program
entry and installed by csu, is installed after any atexit(3) handlers
installed by main binary constructors. This means that rtld_exit() is
fired before main binary handlers.
Typical C++ static constructors are executed from init (either binary
or libs) but use atexit(3) to ensure that destructors are called in
the right order, independent of the linking order. Also, C++
libraries finalizers call __cxa_finalize(3) to flush library'
atexit(3) entries. Since atexit(3) entry is cleared after being run,
this would be mostly innocent, except that, atexit(rtld_exit) done
after main binary constructors, makes destructors from libraries
executed before destructors for main.
Fix by reordering atexit(rtld_exit) before inits for main binary, same
as it happened when inits were called by csu. Do it using new private
libc symbol with pre-defined ABI.
Reported. tested, and reviewed by: kan
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
r340744 broke the NFSv4 client, because it replaced pfind_locked() with a
call to pfind(), since pfind() acquires the sx lock for the pid hash and
the NFSv4 already holds a mutex when it does the call.
The patch fixes the problem by recreating a pfind_any_locked() and adding the
functions pidhash_slockall() and pidhash_sunlockall to acquire/release
all of the pid hash locks.
These functions are then used by the NFSv4 client instead of acquiring
the allproc_lock and calling pfind().
Reviewed by: kib, mjg
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D19887
This causes some increase of the dynamic linker size, but benefits of
avoiding compiling private copy or the linker when debugging is
required. definitely worth it.
The dbg() calls can be compiled out by defining LD_NO_DEBUG symbol.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
depths > 8. Add some smaller optimizations for these depths. Use a
more generic method for all depths >= 8, although this gives tiny
pessimizations for these depths.
For clearing the whole frame buffer, avoid the same pessimizations
for depths > 8. Add some larger optimizations for these depths. Use
an even more generic method for all depths >= 8 to give the optimizations
for depths > 8 and a tiny pessimization for depth 8.
The main pessimization was that old versions of bcopy() copy 1 byte at a
time for all trailing bytes. (i386 still does this. amd64 now pessimizzes
large sizes instead of small ones if the CPU supports ERMS. dev/fb gets
this wrong by mostly not using the bcopy() family or the technically correct
bus space functions but by mostly copying 2 bytes at a time using an
unoptimized loop without even volatile declarations to prevent the compiler
rewriting it.)
The sizes here are 1, 2, 3 or 4 bytes, so depths 9-16 were up to twice as
slow as necessary and depths 17-24 were up to 3 times slower than necessary.
Fix this (except depths 17-24 are still up to 2 times slower than necessary)
by using (builtin) memcpy() instead of bcopy() and reorganizing so that the
complier can see the small constant sizes. Reduce special cases while
reorganizing although this is slightly slower than adding special cases.
The compiler inlining (and even -O2 vs -O0) makes little difference compared
with reducing the number of accesses except on modern hardware it gives a
small improvement.
Clearing was also pessimized mainly by the extra accesses. Fix it quite
differently by creating a MEMBUF containing 1 line (in fast memory using
a slow method) and copying this. This is only slightly slower than reducing
everything to efficient memset()s and bcopy()s, but simpler, especially
for the segmented case. This works for planar modes too, but don't use it
then since the old method was actually optimal for planar modes (it works
by moving the slow i/o instructions out of inner loops), while for direct
modes the slow instructions were all in the invisible inner loop in bcopy().
Use htole32() and le32toh() and some type puns instead of unoptimized
functions for converting colors. This optimization is mostly in the noise.
libvgl is only supported on x86, so it could hard-code the assumption that
the byte order is le32, but the old conversion functions didn't hard-code
this.
* Use `MIN` instead of similar hand rolled macro.
* Sort headers.
* Use `errno.h` instead of `sys/errno.h`.
* Wrap the argument to sizeof in parentheses for clarity.
* Remove `__BSD_VISIBLE` and `_XOPEN_SOURCE` #defines to mute warnings about
incompatible snprintf definitions.
This fixes a number of warnings I've been seeing lately in my builds.
Sort makefile variables per style.Makefile(9) (`CFLAGS`/`CWARNFLAG.gcc`) and
bump `WARNS` to 3.
MFC after: 2 weeks
Reviewed by: jtl
Approved by: jtl (mentor)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D19851
Backing out commit pending further discussion on the PCIe version
supported by pseudo (i.e. emulated) devices. See Differential for
details.
Reviewed by: imp
Approved by: imp (mentor)
Differential Revision: https://reviews.freebsd.org/D19580
PR#223036 reported that INET6 callback addresses were not printed by
nfsdumpstate(8). This kernel patch adds INET6 addresses to the dump structure,
so that nfsdumpstate(8) can print them out, post-r346190.
The patch also includes the addition of #ifdef INET, INET6 as requested
by bz@.
PR: 223036
Reviewed by: bz, rgrimes
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D19839
The patch adds support for printing of INET6 callback addresses.
It also adds the #ifdef INET, INET6 as requested by bz@.
PR: 223036
Reviewed by: bz, rgrimes
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D19839
last allocated block of the file and if that is found, shortens the
file to reference the last allocated block thus avoiding having it
reference a hole at its end.
This update corrects an error where fsck_ffs miscalculated the last
logical block of the file when the file contained a large hole.
Reported by: Jamie Landeg-Jones
Tested by: Peter Holm
MFC after: 2 weeks
Sponsored by: Netflix
ensure that the ip_hl field is valid. Furthermore, ensure that the complete
IPv4 header is contained in the first mbuf. Finally, move the length checks
before relying on them when accessing fields of the IPv4 header.
Reported by: jtl@
Reviewed by: jtl@
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D19181
Experimentally, reduces sort -R time of a 148160 line corpus from about
3.15s to about 0.93s on this particular system.
There's probably room for improvement using some digest other than md5, but
I don't want to look at sort(1) anymore. Some discussion of other possible
improvements in the Test Plan section of the Differential.
PR: 230792
Reviewed by: jhb (earlier version)
Differential Revision: https://reviews.freebsd.org/D19885
Summary:
Initial NUMA support:
- associate CPU with domain
- associate memory ranges with domain
- identify domain for devices
- limit device interrupt binding to appropriate domain
- Additionally fixes a bug in the setting of Maxmem which led to
only memory attached to the first socket being enabled for DMA
A pmap variant can opt in to numa support by by calling `numa_mem_regions`
at the end of pmap_bootstrap - registering the corresponding ranges with the
VM.
This yields a ~20% improvement in build times of llvm on dual socket POWER9
over non-NUMA.
Original patch by mmacy.
Differential Revision: https://reviews.freebsd.org/D17933
Fix some execution bugs in the dtrace powerpc asm. addme pulls in the carry
flag which we don't want, and the result wasn't recorded anyways, so the
following beq to check for exit condition wasn't checking the right
condition.
Simplify the stack walking in dtrace_isa.c, so there's only a single walker
that handles both pc and sp. This should make it easier to follow, and any
bugfix that may be needed for walking only needs to be made in one place
instead of two now.
MFC after: 2 weeks
Forgot to add the changes for DELAY(), which lowers priority during the
delay period. Also, mark the timebase read as volatile so newer GCC does
not optimize it away, as it reportedly does currently.
MFC after: 2 weeks
MFC with: r346144
Otherwise we might dereference NULL vp->v_data after
VP_TO_TMPFS_NODE().
Reported and tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
PowerISA 2.07 and PowerISA 3.0 both specify special NOPs for priority
adjustments, with "medium" priority being normal. We had been setting
medium-low as our normal priority. Rather than guess each time as to what
we want and the right NOP, wrap them in inline functions, and replace the
occurrances of the NOPs with the functions. Also, make DELAY() drop to very
low priority while waiting, so we don't burn CPU.
Coupled with r346143, this shaves off a modest 5-8% on buildworld times with
-j72. There may be more room for improvement with judicious use of these
NOPs.
MFC after: 2 weeks
The POWER9 documentation specifies that levels 0-3 are the 'lightest' sleep
level, meaning lowest latency and with no state loss. However, state 3 is
not implemented, and is instead reserved for future chips. This now
properly configures the PSSCR, specifying state 2 as the lowest level to
enter, but request level 0 for quickest sleep level. If the OCC determines
that the CPU can enter states 1 or 2 it will trigger the transition to those
states on demand.
MFC after: 1 week
It was pointed out that manually loading a .dtb to be used rather than
relying on platform-specific method for loading .dtb will result in overlays
not being applied. This was true because overlay loading was hacked into
fdt_platform_load_dtb, rather than done in a way more independent from how
the .dtb is loaded.
Instead, push overlay loading (for now) out into an
fdt_platform_load_overlays. This method easily allows ubldr to pull in any
fdt_overlays specified in the ub env, and omits overlay-checking on
platforms where they're not tested and/or not desired (e.g. powerpc). If we
eventually stop caring about fdt_overlays from ubenv (if we ever cared),
this method should get chopped out in favor of just calling
fdt_load_dtb_overlays() directly.
Reported by: Manuel Stühn (freebsdnewbie freenet de)
In review D19876 ian@ has some proposed improvements to the
tools/boot/ci-qemu-test.sh script. Start specifying the location of
OVMF.fd fetched by the Cirrus-CI build in advance of those changes.
When leaving a multicast group, a hole may be created in the inpcb's
source filter and group membership arrays. To remove the hole, the
succeeding array elements are copied over by one entry. The multicast
code expects that a newly allocated array element is initialized, but
the code which shifts a tail of the array was leaving stale data
in the final entry. Fix this by explicitly reinitializing the last
entry following such a copy.
Reported by: syzbot+f8c3c564ee21d650475e@syzkaller.appspotmail.com
Reviewed by: ae
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19872
Bound input file processing length to avoid the issue reported in [1]. For
simplicity, only allow regular file and character device inputs. For
character devices, only allow /dev/random (and /dev/urandom symblink).
32 bytes of random is perfectly sufficient to seed MD5; we don't need any
more. Users that want to use large files as seeds are encouraged to truncate
those files down to an appropriate input file via tools like sha256(1).
(This does not change the sort algorithm of sort -R.)
[1]: https://lists.freebsd.org/pipermail/freebsd-hackers/2018-August/053152.html
PR: 230792
Reported by: Ali Abdallah <aliovx AT gmail.com>
Relnotes: yes
