Posted by
michael
on from the sauce-for-the-gander dept.
SirTimbly writes: "CNET is reporting that there is a buffer overflow problem with zlib in linux, which is used for network compression. Supposedly, someone could remotely cause a buffer overflow through mozilla, X11 and many other programs." The advisory from Red Hat is available.
It's not a problem in zlib per se
by
Starship+Trooper
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· Score: 5, Insightful
This bug causes zlib to free() a malloc'ed block of memory more than once. free() on most other OS's (including Windows, FreeBSD and OpenBSD) is smart enough to check for this and will print a warning instead of destroying the heap; glibc's malloc (and by extension, Linux's) does not and will gleefully make a mess out of the whole memory space. This can cause all sorts of buggery when the next malloc() occurs, including what amounts to a buffer overflow exploit.
So, you should download the patched zlib, but you should also email the glibc maintainers and demand that they implement a sane, error-checking malloc()/free() system. Linux's current allocation model is a disaster waiting to happen.
-- Loneliness is a power that we possess to give or take away forever
Re:It's not a problem in zlib per se
by
Anonymous Coward
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· Score: 4, Insightful
so what you are saying is that slashdot has been wrong in the past to criticise microsoft for seeking performance ahead of robustness. glad we've cleared things up.
Then there's still a problem in glibc malloc()
by
Starship+Trooper
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· Score: 5, Insightful
*BSD's malloc manages to simultaneously provide high performance while also providing robust (and highly configurable) error checking. glibc's MALLOC_CHECK_ variable does far too much and isn't nearly as fine-grained as BSD's options. Read the "TUNING" section of FreeBSD's malloc(3) manpage. It puts Linux to shame as far as clarity, usefulness, and convenience goes. You only turn on the error checks you need, instead of a few general and poorly-implemented checks in glibc's malloc.
Why Linux can't follow in the supposedly-inferior BSD's footsteps is beyond me.
-- Loneliness is a power that we possess to give or take away forever
Slashdot Mirror
So, you should download the patched zlib, but you should also email the glibc maintainers and demand that they implement a sane, error-checking malloc()/free() system. Linux's current allocation model is a disaster waiting to happen.
Loneliness is a power that we possess to give or take away forever
All of whom were stamped out within hours of being found.
That's the strength of open source.
El riesgo vive siempre!
Why Linux can't follow in the supposedly-inferior BSD's footsteps is beyond me.
Loneliness is a power that we possess to give or take away forever