[PATCH 5.10 07/79] wifi: iwlegacy: 4965: corrected fix for potential off-by-one overflow in il4965_rs_fill_link_cmd()

Greg Kroah-Hartman
2022-09-13T14:45:07Z

From: Stanislaw Gruszka <stf_xl@wp.pl>

commit 6d0ef7241553f3553a0a2764c69b07892705924c upstream.

This reverts commit a8eb8e6f7159c7c20c0ddac428bde3d110890aa7 as
it can cause invalid link quality command sent to the firmware
and address the off-by-one issue by fixing condition of while loop.

Cc: stable@vger.kernel.org
Fixes: a8eb8e6f7159 ("wifi: iwlegacy: 4965: fix potential off-by-one overflow in il4965_rs_fill_link_cmd()")
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220815073737.GA999388@wp.pl
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/wireless/intel/iwlegacy/4965-rs.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

--- a/drivers/net/wireless/intel/iwlegacy/4965-rs.c
+++ b/drivers/net/wireless/intel/iwlegacy/4965-rs.c
@@ -2403,7 +2403,7 @@ il4965_rs_fill_link_cmd(struct il_priv *
/* Repeat initial/next rate.
* For legacy IL_NUMBER_TRY == 1, this loop will not execute.
* For HT IL_HT_NUMBER_TRY == 3, this executes twice. */
- while (repeat_rate > 0) {
+ while (repeat_rate > 0 && idx < (LINK_QUAL_MAX_RETRY_NUM - 1)) {
if (is_legacy(tbl_type.lq_type)) {
if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
ant_toggle_cnt++;
@@ -2422,8 +2422,6 @@ il4965_rs_fill_link_cmd(struct il_priv *
cpu_to_le32(new_rate);
repeat_rate--;
idx++;
- if (idx >= LINK_QUAL_MAX_RETRY_NUM)
- goto out;
}

il4965_rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
@@ -2468,7 +2466,6 @@ il4965_rs_fill_link_cmd(struct il_priv *
repeat_rate--;
}

-out:
lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_DEF;
lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;