From: Johannes Berg Date: Wed, 4 Sep 2019 14:23:27 +0000 (+0200) Subject: iwlwifi: pcie: fix indexing in command dump for new HW X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=08326a97afbe808e50e1610c2835fa2747bdb908;p=linux.git iwlwifi: pcie: fix indexing in command dump for new HW We got a crash in iwl_trans_pcie_get_cmdlen(), while the TFD was being accessed to sum up the lengths. We want to access the TFD here, which is the information for the hardware. We always only allocate 32 buffers for the cmd queue, but on newer hardware (using TFH) we can also allocate only a shorter hardware array, also only 32 TFDs. Prior to the TFH, we had to allocate a bigger TFD array but would make those point to a smaller set of buffers. Additionally, now max_tfd_queue_size is up to 65536, so we can access *way* out of bounds of a really only 32-entry array, so it crashes. Fix this by making the TFD index depend on which hardware we are using right now. While changing the calculation, also fix it to not use void ptr arithmetic, but cast to u8 * before. Signed-off-by: Johannes Berg Signed-off-by: Luca Coelho --- diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c index f8a1f985a1d85..ab7480a85015e 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c @@ -3272,11 +3272,17 @@ static struct iwl_trans_dump_data ptr = cmdq->write_ptr; for (i = 0; i < cmdq->n_window; i++) { u8 idx = iwl_pcie_get_cmd_index(cmdq, ptr); + u8 tfdidx; u32 caplen, cmdlen; + if (trans->trans_cfg->use_tfh) + tfdidx = idx; + else + tfdidx = ptr; + cmdlen = iwl_trans_pcie_get_cmdlen(trans, - cmdq->tfds + - tfd_size * ptr); + (u8 *)cmdq->tfds + + tfd_size * tfdidx); caplen = min_t(u32, TFD_MAX_PAYLOAD_SIZE, cmdlen); if (cmdlen) {