Tom Stellard
7451594338
Marking heap memory as executable using mprotect() is not allowed
by SELinux. mprotect() calls that try to do this will fail on systems
with SELinux enabled. This is also a security risk, so it should be
fixed even on systems that allow this.
Any memory we want to mark as executable must be allocated using mmap().
See https://www.akkadia.org/drepper/selinux-mem.html
The two places where we try to mark heap memory as executable both use
posix_memalign() to allocate the heap memory. In both cases, the
alignment value passed into this function is always equal to PAGE_SIZE,
which means that they are safe to replace with mmap(), which guarantees
alignment to PAGE_SIZE. In this case PAGE_SIZE has been set to
sysconf(_SC_PAGESIZE);
v2:
- Use MAP_PRIVATE instead of MAP_SHARED. This matches the behavior
of memory allocated by posix_memalign()
- Ignore alignment hints instead of returning error when we can't
accommodate them.
- Drop alignment parameter of allocate_exec_aligned_memory() since
the only alignment supported is sysconf(_SC_PAGESIZE).
- Remove extra parameter from fmm_release().
- Add error path to fmm_allocate_host_cpu() for when mmap fails.
v3:
- Avoid use after free.
Change-Id: I7d51279790d9700bc3fa761c44bfde1c1936019b
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
[ROCm/ROCR-Runtime commit: e2ed9cf79a]