FreeBSD src
a9a0bbad19
because we could fail due to a small buffer and loop and rerun. If this happens, then the vsnprintf() will have already taken the arguments off the va_list. For i386 and others, this doesn't matter because the va_list type is a passed as a copy. But on powerpc and amd64, this is fatal because the va_list is a reference to an external structure that keeps the vararg state due to the more complicated argument passing system. On amd64, arguments can be passed as follows: First 6 int/pointer type arguments go in registers, the rest go on the memory stack. Float and double are similar, except using SSE registers. long double (80 bit precision) are similar except using the x87 stack. Where the 'next argument' comes from depends on how many have been processed so far and what type it is. For amd64, gcc keeps this state somewhere that is referenced by the va_list. I found a description that showed the va_copy was required here: http://mirrors.ccs.neu.edu/cgi-bin/unixhelp/man-cgi?va_end+9 The single unix spec doesn't mention va_copy() at all. Anyway, the problem was that the sysctl kern.geom.conf* nodes would panic due to walking off the end of the va_arg lists in vsnprintf. A better fix would be to have sbuf_vprintf() use a single pass and call kvprintf() with a callback function that stored the results and grew the buffer as needed. Approved by: re (scottl) |
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| bin | ||
| contrib | ||
| crypto | ||
| etc | ||
| games | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| COPYRIGHT | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| README | ||
| UPDATING | ||
This is the top level of the FreeBSD source directory. This file was last revised on: $FreeBSD$ For copyright information, please see the file COPYRIGHT in this directory (additional copyright information also exists for some sources in this tree - please see the specific source directories for more information). The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree, the most commonly used one being ``world'', which rebuilds and installs everything in the FreeBSD system from the source tree except the kernel, the kernel-modules and the contents of /etc. The ``buildkernel'' and ``installkernel'' targets build and install the kernel and the modules (see below). Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel is a somewhat more involved process, documentation for which can be found at: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html And in the config(8) man page. Note: If you want to build and install the kernel with the ``buildkernel'' and ``installkernel'' targets, you might need to build world before. More information is available in the handbook. The sample kernel configuration files reside in the sys/<arch>/conf sub-directory (assuming that you've installed the kernel sources), the file named GENERIC being the one used to build your initial installation kernel. The file NOTES contains entries and documentation for all possible devices, not just those commonly used. It is the successor of the ancient LINT file, but in contrast to LINT, it is not buildable as a kernel but a pure reference and documentation file. Source Roadmap: --------------- bin System/user commands. contrib Packages contributed by 3rd parties. crypto Cryptography stuff (see crypto/README). etc Template files for /etc. games Amusements. gnu Various commands and libraries under the GNU Public License. Please see gnu/COPYING* for more information. include System include files. kerberos5 Kerberos5 (Heimdal) package. lib System libraries. libexec System daemons. release Release building Makefile & associated tools. sbin System commands. secure Cryptographic libraries and commands. share Shared resources. sys Kernel sources. tools Utilities for regression testing and miscellaneous tasks. usr.bin User commands. usr.sbin System administration commands. For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html