wifi: iwlwifi: pcie: Fix TSO preparation

commit bbb18f7e23a3f5f56d5c8b4ee0f78f00edb3b1b2 upstream.

The allocation of the scatter gather data structure should be done
based on the number of memory chunks that need to be mapped, and it
is not dependent on the overall payload length. Fix it.

In addition, as the skb_to_sgvec() function returns an 'int' do not
assign it to an 'unsigned int' as otherwise the error check would be
useless.

Fixes: 7f5e3038f029 ("wifi: iwlwifi: map entire SKB when sending AMSDUs")
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20250306122425.8c0e23a3d583.I3cb4d6768c9d28ce3da6cd0a6c65466176cfc1ee@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
index a74ce5ccf59bd29dcc5010219d3260869e6eaff2..9fcdd06e126ae1e2a161fb7a9df1bc15c2ae6b52 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
@@ -1867,12 +1867,12 @@ struct sg_table *iwl_pcie_prep_tso(struct iwl_trans *trans, struct sk_buff *skb,
                                   unsigned int offset)
 {
        struct sg_table *sgt;
-       unsigned int n_segments;
+       unsigned int n_segments = skb_shinfo(skb)->nr_frags + 1;
+       int orig_nents;
 
        if (WARN_ON_ONCE(skb_has_frag_list(skb)))
                return NULL;
 
-       n_segments = DIV_ROUND_UP(skb->len - offset, skb_shinfo(skb)->gso_size);
        *hdr = iwl_pcie_get_page_hdr(trans,
                                     hdr_room + __alignof__(struct sg_table) +
                                     sizeof(struct sg_table) +
@@ -1887,11 +1887,12 @@ struct sg_table *iwl_pcie_prep_tso(struct iwl_trans *trans, struct sk_buff *skb,
        sg_init_table(sgt->sgl, n_segments);
 
        /* Only map the data, not the header (it is copied to the TSO page) */
-       sgt->orig_nents = skb_to_sgvec(skb, sgt->sgl, offset,
-                                      skb->len - offset);
-       if (WARN_ON_ONCE(sgt->orig_nents <= 0))
+       orig_nents = skb_to_sgvec(skb, sgt->sgl, offset, skb->len - offset);
+       if (WARN_ON_ONCE(orig_nents <= 0))
                return NULL;
 
+       sgt->orig_nents = orig_nents;
+
        /* And map the entire SKB */
        if (dma_map_sgtable(trans->dev, sgt, DMA_TO_DEVICE, 0) < 0)
                return NULL;