block/vvfat: Fix crash when reporting error about too many files in directory

When using the vvfat driver with a directory that contains too many files,
QEMU currently crashes. This can be triggered like this for example:

 mkdir /tmp/vvfattest
 cd /tmp/vvfattest
 for ((x=0;x<=513;x++)); do mkdir $x; done
 qemu-system-x86_64 -drive \
   file.driver=vvfat,file.dir=.,read-only=on,media=cdrom

Seems like read_directory() is changing the mapping->path variable. Make
sure we use the right pointer instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Thomas Huth 2018-07-24 13:52:04 +02:00 committed by Kevin Wolf
parent b2f7a038bb
commit a2b83a5165

View File

@ -973,10 +973,10 @@ static int init_directories(BDRVVVFATState* s,
mapping = array_get(&(s->mapping), i);
if (mapping->mode & MODE_DIRECTORY) {
char *path = mapping->path;
mapping->begin = cluster;
if(read_directory(s, i)) {
error_setg(errp, "Could not read directory %s",
mapping->path);
error_setg(errp, "Could not read directory %s", path);
return -1;
}
mapping = array_get(&(s->mapping), i);