Re: panic: Memory modified after free

From: Thierry Herbelot <thierry_at_herbelot.com>
Date: Fri, 24 Jun 2005 17:37:55 +0200
Le Friday 24 June 2005 17:03, Kris Kennaway a écrit :
> On Fri, Jun 24, 2005 at 04:26:55PM +0200, Thierry Herbelot wrote:
> > This is with an SMP machine (oldish BP6)
>
> Looks like you forgot to include the full panic...wasn't there a "last
> used by FOO" also displayed?  If so, you should configure
> DEBUG_MEMGUARD to watch this malloc type (some assembly required, but
> it's pretty straightforward -- see Bosko Milekic's post to this
> mailing list when he committed support describing how to do it) and
> try to replicate the panic.

sorry if I forgot anything :
this is the only message I had on the serial console :

[traditional dmesg startup messages]

Local package initialization:.
Additional TCP options:.
Starting background file system checks in 60 seconds.

Fri Jun 24 09:10:10 CEST 2005

FreeBSD/i386 (multi-cur.herbelot.nom) (ttyd0)

login: Jun 24 09:11:02 multi-cur su: thierry.herbelot to root on /dev/ttyp0
panic: Memory modified after free 0xc15c1400(256) val=0 _at_ 0xc15c1400

cpuid = 0
KDB: enter: panic
[thread pid 520 tid 100070 ]
Stopped at      kdb_enter+0x2b: nop
db> where
Tracing pid 520 tid 100070 td 0xc1508780
kdb_enter(c084ecf5) at kdb_enter+0x2b
panic(c08695fc,c15c1400,100,0,c15c1400) at panic+0x127
trash_ctor(c15c1400,100,cc89db40,1,c104a9d8) at trash_ctor+0x2f
mb_ctor_mbuf(c15c1400,100,cc89db40,1) at mb_ctor_mbuf+0x18
uma_zalloc_arg(c104a9a0,cc89db40,1) at uma_zalloc_arg+0x10f

[rest of the ddb session]

I forgot to add : this is with a straight GENERIC kernel, built from sources 
cvsupped around yesterday Jun 23 20:00:00 CEST 2005

the full dmesg is accessible at :
http://herbelot.tfh.free.fr/050624.trace

	Cheers

	TfH


>
> Kris
Received on Fri Jun 24 2005 - 13:38:05 UTC

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