[Qemu-devel] qemu-arm fails on test-mmap

[Jan-Simon Möller]

Hi!

I've spotted an bug in mmap for the qemu-arm . It causes a segfault of qemu or 
at least the running process.

Its reproducible here with "test-mmap" .

legolas:/> qemu-arm ./test-mmap
pagesize=4096 pagemask=fff
check_aligned_anonymous_unfixed_mmaps passed
check_aligned_anonymous_unfixed_colliding_mmapsSegmentation fault (core dumped)


A lengthy trace with debugging on in mmap.c is at
http://filebin.ca/yxypzq/qemu_mmap_segfault.bz2

[... last mmap call ...]
munmap: start=0x5fffd000 len=0x00001000
mmap: start=0x00000000 len=0x00008000 prot=r-- flags=MAP_ANON MAP_PRIVATE fd=-1 
offset=00000000
ret=0x5ffff000
start    end      size     prot
00008000-0000b000 00003000 r-x
00012000-00013000 00001000 r--
00013000-00037000 00024000 rw-
40000000-40080000 00080000 rw-
40080000-40081000 00001000 ---
40081000-4009f000 0001e000 r-x
4009f000-400a6000 00007000 ---
400a6000-400a7000 00001000 r--
400a7000-400a8000 00001000 rw-
400a8000-42081000 01fd9000 ---
42085000-421bf000 0013a000 r-x
421bf000-421c6000 00007000 ---
421c6000-421c8000 00002000 r--
421c8000-421ce000 00006000 rw-
5fffe000-60007000 00009000 r--

Segmentation fault

It seems to hit > 0x5fffffff -> segfault.

Best,
Jan-Simon