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Date: | Mon, 17 Jun 2019 17:33:20 +0300 |
Message-Id: | <83tvcoth73.fsf@gnu.org> |
From: | "Eli Zaretskii (eliz AT gnu DOT org) [via djgpp AT delorie DOT com]" <djgpp AT delorie DOT com> |
To: | djgpp AT delorie DOT com |
In-reply-to: | <qe76u1$1kj8$1@gioia.aioe.org> (message from Rod Pemberton on |
Mon, 17 Jun 2019 01:05:38 -0400) | |
Subject: | Re: malloc() returns pointer to already allocated memory |
References: | <158e5d20-0a90-4beb-de48-da328379d8fb AT gmail DOT com> <qe76u1$1kj8$1 AT gioia DOT aioe DOT org> |
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> From: Rod Pemberton <invalid AT lkntrgzxc DOT com> > Date: Mon, 17 Jun 2019 01:05:38 -0400 > > Second problem is you don't call memset() prior to using memory, nor > free() after you're done using it. Of course, calling memset() would > prevent your method of "clobber" detection from working. But, not > calling memset() means you don't know if the magic clobber value is: > a) from you setting it within your program, or > b) from some random garbage values in memory. Right. There's a startup flag that a program could optionally set to request that allocated memory be filled with a specific fixed value, then tests for clobbering could work. See the documentation of _crt0_startup_flags in the libc manual.
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