From: Petr Vorel <pvorel@suse.cz>
To: Ben Copeland <ben.copeland@linaro.org>
Cc: arnd@arndb.de, lkft-triage@lists.linaro.org, ltp@lists.linux.it,
dan.carpenter@linaro.org
Subject: Re: [LTP] [PATCH] oom03: use size_t for memory length to fix 32-bit overflow
Date: Fri, 17 Oct 2025 18:20:13 +0200 [thread overview]
Message-ID: <20251017162013.GA351168@pevik> (raw)
In-Reply-To: <20251016140303.1645478-1-ben.copeland@linaro.org>
Hi all,
> The alloc_mem() function is supposed to test out of memory conditions.
> How it works is it calls mmap() on a giant chunk of memory.
> It's either LENGTH (2GB) or "TESTMEM * 2 + TST_MB" (3GB) bytes.
> This mmap() is generally supposed to succeed. Then at the bottom of
> the alloc_mem() function when we actually try to use all the memory,
> the thread is supposed to die with a SIGKILL.
> The problem is that length is signed so on a 32-bit system it will be
> negative. That means that at the bottom of the function when we loop
> through the memory, the for loop is a no-op and there is no SIGKILL.
> Fix this by changing the type to size_t which is unsigned.
I dared to change subject to oom.h and merged.
Thanks!
Kind regards,
Petr
--
Mailing list info: https://lists.linux.it/listinfo/ltp
prev parent reply other threads:[~2025-10-17 16:20 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-16 14:03 [LTP] [PATCH] oom03: use size_t for memory length to fix 32-bit overflow Ben Copeland
2025-10-17 9:38 ` Li Wang via ltp
2025-10-17 16:20 ` Petr Vorel [this message]
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