## Description
There is a segment fault detected by AddressSanitizer

## System info
```
Ubuntu 20.04.2 LTS
clang version 12.0.0-++20210402082642+04ba60cfe598-1~exp1~20210402063359.71
MP4Box - GPAC version 1.1.0-DEV-rev1727-g8be34973d-master
```

## Build command
```
./configure --static-mp4box --prefix=`realpath ./install` --enable-sanitizer --cc=clang --cxx=clang++
```

## crash command
```
MP4Box -dmp4 -out /dev/null poc_file
```

## Pocs

[poc.zip](https://github.com/gpac/gpac/files/8020734/poc.zip)


## Crash output
```
==898==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x0000005b875b bp 0x7fff1f6fc650 sp 0x7fff1f6fc650 T0)
==898==The signal is caused by a READ memory access.
==898==Hint: address points to the zero page.
    #0 0x5b875b in gf_utf8_wcslen/programs/mp4box/builds/build10/src/utils/utf.c:441:21
    #1 0x7ac4c4 in xtra_box_dump/programs/mp4box/builds/build10/src/isomedia/box_dump.c:6306:40
    #2 0x7b2d7b in gf_isom_box_dump/programs/mp4box/builds/build10/src/isomedia/box_funcs.c:2065:2
    #3 0x782c5a in gf_isom_dump/programs/mp4box/builds/build10/src/isomedia/box_dump.c:135:3
    #4 0x4f7e9c in dump_isom_xml/programs/mp4box/builds/build10/applications/mp4box/filedump.c:1950:6
    #5 0x4e0da8 in mp4boxMain/programs/mp4box/builds/build10/applications/mp4box/main.c:6171:7
    #6 0x7f16b0fc20b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
    #7 0x41ea6d in _start (/zhengjie/cmdline-fuzz/programs/mp4box/builds/build10/bin/gcc/MP4Box+0x41ea6d)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV/programs/mp4box/builds/build10/src/utils/utf.c:441:21 in gf_utf8_wcslen
==898==ABORTING
```
There is a segment fault detected by AddressSanitizer
This is a GitHub Issue
repo:gpac
owner:gpac
Title : There is a segment fault detected by AddressSanitizer
Issue date:

--- start body ---
## Description
There is a segment fault detected by AddressSanitizer

## System info
```
Ubuntu 20.04.2 LTS
clang version 12.0.0-++20210402082642+04ba60cfe598-1~exp1~20210402063359.71
MP4Box - GPAC version 1.1.0-DEV-rev1727-g8be34973d-master
```

## Build command
```
./configure --static-mp4box --prefix=`realpath ./install` --enable-sanitizer --cc=clang --cxx=clang++
```

## crash command
```
MP4Box -dmp4 -out /dev/null poc_file
```

## Pocs

[poc.zip](https://github.com/gpac/gpac/files/8020734/poc.zip)


## Crash output
```
==898==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x0000005b875b bp 0x7fff1f6fc650 sp 0x7fff1f6fc650 T0)
==898==The signal is caused by a READ memory access.
==898==Hint: address points to the zero page.
    #0 0x5b875b in gf_utf8_wcslen/programs/mp4box/builds/build10/src/utils/utf.c:441:21
    #1 0x7ac4c4 in xtra_box_dump/programs/mp4box/builds/build10/src/isomedia/box_dump.c:6306:40
    #2 0x7b2d7b in gf_isom_box_dump/programs/mp4box/builds/build10/src/isomedia/box_funcs.c:2065:2
    #3 0x782c5a in gf_isom_dump/programs/mp4box/builds/build10/src/isomedia/box_dump.c:135:3
    #4 0x4f7e9c in dump_isom_xml/programs/mp4box/builds/build10/applications/mp4box/filedump.c:1950:6
    #5 0x4e0da8 in mp4boxMain/programs/mp4box/builds/build10/applications/mp4box/main.c:6171:7
    #6 0x7f16b0fc20b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
    #7 0x41ea6d in _start (/zhengjie/cmdline-fuzz/programs/mp4box/builds/build10/bin/gcc/MP4Box+0x41ea6d)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV/programs/mp4box/builds/build10/src/utils/utf.c:441:21 in gf_utf8_wcslen
==898==ABORTING
```
--- end body ---
