From: Arve Hjønnevåg Date: Fri, 14 Feb 2014 04:25:06 +0000 (-0800) Subject: android: binder: More offset validation. X-Git-Tag: firefly_0821_release~4090^2~106 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=3ce49f5ed6c76a7772aeba7419d4976f225e1b78;p=firefly-linux-kernel-4.4.55.git android: binder: More offset validation. Make sure offsets don't point to overlapping flat_binder_object structs. Change-Id: I85c759b9c6395492474b177625dc6b0b289fd6b0 Signed-off-by: Arve HjønnevÃ¥g --- diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 52aae90eb1fd..b9242c6905ba 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -1322,6 +1322,7 @@ static void binder_transaction(struct binder_proc *proc, struct binder_transaction *t; struct binder_work *tcomplete; binder_size_t *offp, *off_end; + binder_size_t off_min; struct binder_proc *target_proc; struct binder_thread *target_thread = NULL; struct binder_node *target_node = NULL; @@ -1518,18 +1519,24 @@ static void binder_transaction(struct binder_proc *proc, goto err_bad_offset; } off_end = (void *)offp + tr->offsets_size; + off_min = 0; for (; offp < off_end; offp++) { struct flat_binder_object *fp; if (*offp > t->buffer->data_size - sizeof(*fp) || + *offp < off_min || t->buffer->data_size < sizeof(*fp) || !IS_ALIGNED(*offp, sizeof(u32))) { - binder_user_error("%d:%d got transaction with invalid offset, %lld\n", - proc->pid, thread->pid, (u64)*offp); + binder_user_error("%d:%d got transaction with invalid offset, %lld (min %lld, max %lld)\n", + proc->pid, thread->pid, (u64)*offp, + (u64)off_min, + (u64)(t->buffer->data_size - + sizeof(*fp))); return_error = BR_FAILED_REPLY; goto err_bad_offset; } fp = (struct flat_binder_object *)(t->buffer->data + *offp); + off_min = *offp + sizeof(struct flat_binder_object); switch (fp->type) { case BINDER_TYPE_BINDER: case BINDER_TYPE_WEAK_BINDER: {