Messages in this thread | | | From | David Laight <> | Subject | RE: [PATCH] mm: optionally disable brk() | Date | Fri, 2 Oct 2020 21:19:33 +0000 |
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From: David Hildenbrand > Sent: 02 October 2020 18:52 > > On 02.10.20 19:19, Topi Miettinen wrote: > > The brk() system call allows to change data segment size (heap). This > > is mainly used by glibc for memory allocation, but it can use mmap() > > and that results in more randomized memory mappings since the heap is > > always located at fixed offset to program while mmap()ed memory is > > randomized. > > Want to take more Unix out of Linux? > > Honestly, why care about disabling? User space can happily use mmap() if > it prefers.
I bet some obscure applications rely on it.
Although hopefully nothing still does heap allocation by just increasing the VA and calling brk() in response to SIGSEGV.
David
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