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Date: Tue, 4 Jan 2022 15:27:10 -0600
From: Nihal Jere <>
Subject: Dynamic linker segfault


ldd from master segfaults when run on [1] and [2]. It happens on
this[3] line. It seems to happen due to the intersection of a few

1. The segment at the lowest address is read-only.
2. A segment on the the same page is read/write.
3. The read/write segment has memsz > filesz.

This results in a segfault, as it tries to memset[3] on the mmap
created here[4], which has the same protection as the segment at
the lowest address (i.e. read-only).

As far as I can see, the options are to either:

a. detect this and throw an error.
b. 'or' together the protection flags of all the segments on the page.

I'm not sure what the right behavior is, but I don't think segfaulting
is right, and I'm sure there are people here what's correct.



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