out to be a problem with VJ header compression.
davidg spotted this in usr.sbin/ppp/slcompress.c
a while ago, but I believe gave the wrong reasons -
it's too easy to reproduce ! The only scenario that
I've been able to reproduce the problem under is when
m_len is *exactly* 40 ! So go figure !
PR: 3749
Submitted elsewhere by: davidg
Obtained from: usr.sbin/ppp/slcompress.c
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
header for use in decompressing subsequant packets. If cslip gets garbage
(such as what happens when there is a port speed mismatch or modem line
noise), it will occasionally mistake the packet as a valid uncompressed
packet. When it tries to save off the header, it doesn't bother to check
for the validity of the header length and will happily clobber not only
the cslip data structure, but parts of other kernel memory that happens
to follow it...causing, ahem, undesired behavior.
if_sl and if_ppp (from ppp-2.2), eliminating the nearly identical
pppcompress.[ch] code. Add maximum VJ compression states argument to
sl_compress_init().
if_sl: call sl_compress_init() with the extra argument.
- Delete redundant declarations.
- Add -Wredundant-declarations to Makefile.i386 so they don't come back.
- Delete sloppy COMMON-style declarations of uninitialized data in
header files.
- Add a few prototypes.
- Clean up warnings resulting from the above.
NB: ioconf.c will still generate a redundant-declaration warning, which
is unavoidable unless somebody volunteers to make `config' smarter.
