https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111413
Bug ID: 111413
Summary: libgomp >= 13 segfault on loading if environ is NULL
Product: gcc
Version: og13 (devel/omp/gcc-13)
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libgomp
Assignee: unassigned at gcc dot gnu.org
Reporter: silvio at traversaro dot it
CC: jakub at gcc dot gnu.org
Target Milestone: ---
Created attachment 55900
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=55900&action=edit
Example to reproduce the issue, compile with gcc -ldl test_gomp_segfault.c -o
test_gomp_segfault
Since release 13, it seems that libgomp fails on loading in the environ global
variable is NULL, for example if clearenv
(https://man7.org/linux/man-pages/man3/clearenv.3.html) was called before a
dlopen.
The problem seems in
https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=libgomp/env.c;hb=73a0d3bf895b5c322676178a51ac0d68cf603953#l2227,
where `environ` is dereferenced without first checking if it is NULL.
A minimal reproducer is attached to the issue, that can be compiled and run as:
gcc -ldl test_gomp_segfault.c -o test_gomp_segfault
./test_gomp_segfault
