Fix NULL deref segfault in bhyve's usb_mouse.c #1728
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Bugzilla link: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=282237 > Some of the cases inside umouse_request() (usr.sbin/bhyve/usb_mouse.c) use the data component of an event, while only partially checking if it's NULL. > > For example: > ``` case UREQ(UR_GET_STATUS, UT_READ_INTERFACE): case UREQ(UR_GET_STATUS, UT_READ_ENDPOINT): DPRINTF(("umouse: (UR_GET_STATUS, UT_READ_INTERFACE)")); if (data != NULL && len > 1) { USETW(udata, 0); data->blen = len - 2; data->bdone += 2; } eshort = data->blen > 0; break; > ``` > As you can see, 'data' has a NULL check, but then 'data' is immediately deferenced anyway after the check regardless of if it's NULL or not. > > There are actually four occurrences of this same bug, each in a different case in this switch block. > > Cheers, > Jack Bendtsen
Signed-off-by: Jack Bendtsen <jackdbendtsen@gmail.com>
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Bugzilla link:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=282237
Signed-off-by: Jack Bendtsen jackdbendtsen@gmail.com