monitor: fix use after free

The function monitor_fdset_dup_fd_find_remove() references member of
'mon_fdset' which - when remove flag is set - may be freed in function
monitor_fdset_cleanup().
remove is set by monitor_fdset_dup_fd_remove which in practice
does not need the returned value, so make it void,
and return -1 from monitor_fdset_dup_fd_find_remove.

Reported-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
This commit is contained in:
Michael S. Tsirkin 2014-08-17 11:45:17 +02:00 committed by Luiz Capitulino
parent 2928207ac1
commit b3dd1b8c29
3 changed files with 7 additions and 6 deletions

View file

@ -64,7 +64,7 @@ AddfdInfo *monitor_fdset_add_fd(int fd, bool has_fdset_id, int64_t fdset_id,
Error **errp);
int monitor_fdset_get_fd(int64_t fdset_id, int flags);
int monitor_fdset_dup_fd_add(int64_t fdset_id, int dup_fd);
int monitor_fdset_dup_fd_remove(int dup_fd);
void monitor_fdset_dup_fd_remove(int dup_fd);
int monitor_fdset_dup_fd_find(int dup_fd);
#endif /* !MONITOR_H */

View file

@ -2542,8 +2542,10 @@ static int monitor_fdset_dup_fd_find_remove(int dup_fd, bool remove)
if (QLIST_EMPTY(&mon_fdset->dup_fds)) {
monitor_fdset_cleanup(mon_fdset);
}
return -1;
} else {
return mon_fdset->id;
}
return mon_fdset->id;
}
}
}
@ -2555,9 +2557,9 @@ int monitor_fdset_dup_fd_find(int dup_fd)
return monitor_fdset_dup_fd_find_remove(dup_fd, false);
}
int monitor_fdset_dup_fd_remove(int dup_fd)
void monitor_fdset_dup_fd_remove(int dup_fd)
{
return monitor_fdset_dup_fd_find_remove(dup_fd, true);
monitor_fdset_dup_fd_find_remove(dup_fd, true);
}
int monitor_handle_fd_param(Monitor *mon, const char *fdname)

View file

@ -1,7 +1,6 @@
#include "qemu-common.h"
#include "monitor/monitor.h"
int monitor_fdset_dup_fd_remove(int dupfd)
void monitor_fdset_dup_fd_remove(int dupfd)
{
return -1;
}