freebsd kernel with SKQ
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Mark Johnston 3309fa7403 Plug a race between fd table teardown and several loops
To export information from fd tables we have several loops which do
this:

FILDESC_SLOCK(fdp);
for (i = 0; fdp->fd_refcount > 0 && i <= lastfile; i++)
	<export info for fd i>;
FILDESC_SUNLOCK(fdp);

Before r367777, fdescfree() acquired the fd table exclusive lock between
decrementing fdp->fd_refcount and freeing table entries.  This
serialized with the loop above, so the file at descriptor i would remain
valid until the lock is dropped.  Now there is no serialization, so the
loops may race with teardown of file descriptor tables.

Acquire the exclusive fdtable lock after releasing the final table
reference to provide a barrier synchronizing with these loops.

Reported by:	pho
Reviewed by:	kib (previous version), mjg
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D27513
2020-12-09 14:05:08 +00:00
.github/workflows GH Actions: Use pre-installed clang packages 2020-11-26 14:42:16 +00:00
bin fts_read: Handle error from a NULL return better. 2020-12-08 23:38:26 +00:00
cddl dtrace: honor LC_NUMERIC for %'d and alike, and LC_TIME for %T 2020-12-03 11:59:40 +00:00
contrib MFV r368464: 2020-12-09 02:59:24 +00:00
crypto Merge OpenSSL 1.1.1i. 2020-12-09 02:05:14 +00:00
etc Missed adding netgraph to mtree in r368443: 2020-12-08 17:44:34 +00:00
gnu gnu: don't build libgnuregex for WITH_GNU_GREP_COMPAT 2020-12-04 15:21:12 +00:00
include Import OpenSSL 1.1.1i. 2020-12-08 18:10:16 +00:00
kerberos5 Fix more -Wundef warnings during bootstrap 2020-10-14 12:28:54 +00:00
lib libsysdecode: decode _UMTX_OP flags 2020-12-09 03:22:44 +00:00
libexec When dropping packets (RRQ or WRQ) for debugging, report the send 2020-12-06 18:43:12 +00:00
release Copy arm64 make-memstick.sh and mkisoimages.sh to the riscv 2020-12-09 02:21:25 +00:00
rescue ping: add a ping6 hard link for backwards compatibility 2020-11-26 18:33:04 +00:00
sbin bectl: simplify the tail end of the jail cmd 2020-12-06 15:58:50 +00:00
secure Merge OpenSSL 1.1.1i. 2020-12-09 02:05:14 +00:00
share New Netgraph module ng_macfilter: 2020-12-08 15:09:42 +00:00
stand Properly define the bool type in the BSD kernel shim. 2020-12-07 16:08:31 +00:00
sys Plug a race between fd table teardown and several loops 2020-12-09 14:05:08 +00:00
targets Add WITH_CLANG_FORMAT option 2020-06-24 17:03:42 +00:00
tests New Netgraph module ng_macfilter: 2020-12-08 15:09:42 +00:00
tools riscv: allow building virtual machine images 2020-12-08 00:37:11 +00:00
usr.bin grep: replace the internal queue with a ring buffer 2020-12-09 05:27:45 +00:00
usr.sbin fts_read: Handle error from a NULL return better. 2020-12-08 23:38:26 +00:00
.arcconfig arcconfig: add callsign again 2020-11-23 04:39:29 +00:00
.arclint arc lint: ignore /tests/ in chmod 2017-12-19 03:38:06 +00:00
.cirrus.yml CI: switch to qemu42 package 2020-10-29 02:02:30 +00:00
.clang-format clang-format: Avoid breaking after the opening paren of function definitions 2020-10-28 11:54:00 +00:00
.gitattributes Add a basic clang-format configuration file 2019-06-07 15:23:52 +00:00
.gitignore Stop ignoring makeLINT generated files 2020-10-09 00:27:45 +00:00
COPYRIGHT Happy New Year 2020! 2019-12-31 16:01:36 +00:00
LOCKS LOCKS: update current locks 2018-06-09 03:08:04 +00:00
MAINTAINERS Add a pointer to csprng@ for the CSPRNG driver. This is enforced anyway by 2020-09-01 08:02:12 +00:00
Makefile Makefile: re-wordsmith the blurb about xtoolchain ports 2020-11-14 18:06:35 +00:00
Makefile.inc1 crunchgen: fix NULL-deref bug introduced in r364647 2020-12-04 15:53:37 +00:00
Makefile.libcompat Race in 32-bit fixed 2020-10-08 17:30:05 +00:00
Makefile.sys.inc AUTO_OBJ: For all top-level targets enforce using an OBJDIR. 2017-12-05 21:29:47 +00:00
ObsoleteFiles.inc Add a few missed entries to ObsoleteFiles.inc: 2020-11-30 19:18:50 +00:00
README Import OpenSSL 1.1.1i. 2020-12-08 18:10:16 +00:00
README.md README: add generic notes about GENERIC and NOTES 2018-06-17 19:44:24 +00:00
RELNOTES Add a entry for r367660. 2020-11-14 01:55:02 +00:00
UPDATING Merge ping6 to ping 2020-11-26 04:29:30 +00:00

FreeBSD Source:

This is the top level of the FreeBSD source directory. This file was last revised on: FreeBSD

FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.

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include		System include files.

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stand		Boot loader sources.

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tests		Regression tests which can be run by Kyua.  See tests/README
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