| From d66e9fe71c0bccd3202a8801d22e2b5c706e265e Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 30 Aug 2021 15:32:40 +0800 |
| Subject: mac80211: Fix ieee80211_amsdu_aggregate frag_tail bug |
| |
| From: Chih-Kang Chang <gary.chang@realtek.com> |
| |
| [ Upstream commit fe94bac626d9c1c5bc98ab32707be8a9d7f8adba ] |
| |
| In ieee80211_amsdu_aggregate() set a pointer frag_tail point to the |
| end of skb_shinfo(head)->frag_list, and use it to bind other skb in |
| the end of this function. But when execute ieee80211_amsdu_aggregate() |
| ->ieee80211_amsdu_realloc_pad()->pskb_expand_head(), the address of |
| skb_shinfo(head)->frag_list will be changed. However, the |
| ieee80211_amsdu_aggregate() not update frag_tail after call |
| pskb_expand_head(). That will cause the second skb can't bind to the |
| head skb appropriately.So we update the address of frag_tail to fix it. |
| |
| Fixes: 6e0456b54545 ("mac80211: add A-MSDU tx support") |
| Signed-off-by: Chih-Kang Chang <gary.chang@realtek.com> |
| Signed-off-by: Zong-Zhe Yang <kevin_yang@realtek.com> |
| Signed-off-by: Ping-Ke Shih <pkshih@realtek.com> |
| Link: https://lore.kernel.org/r/20210830073240.12736-1-pkshih@realtek.com |
| [reword comment] |
| Signed-off-by: Johannes Berg <johannes.berg@intel.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| net/mac80211/tx.c | 8 ++++++++ |
| 1 file changed, 8 insertions(+) |
| |
| diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c |
| index 673ad3cf2c3a..bef517ccdecb 100644 |
| --- a/net/mac80211/tx.c |
| +++ b/net/mac80211/tx.c |
| @@ -3365,6 +3365,14 @@ static bool ieee80211_amsdu_aggregate(struct ieee80211_sub_if_data *sdata, |
| if (!ieee80211_amsdu_prepare_head(sdata, fast_tx, head)) |
| goto out; |
| |
| + /* If n == 2, the "while (*frag_tail)" loop above didn't execute |
| + * and frag_tail should be &skb_shinfo(head)->frag_list. |
| + * However, ieee80211_amsdu_prepare_head() can reallocate it. |
| + * Reload frag_tail to have it pointing to the correct place. |
| + */ |
| + if (n == 2) |
| + frag_tail = &skb_shinfo(head)->frag_list; |
| + |
| /* |
| * Pad out the previous subframe to a multiple of 4 by adding the |
| * padding to the next one, that's being added. Note that head->len |
| -- |
| 2.33.0 |
| |