4.9-stable review patch. If anyone has any objections, please let me know.
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From: Matthias Kaehlcke mka@chromium.org
commit aa1702dd162f420bf85ecef0c77686ef0dbc1496 upstream.
__ieee80211_amsdu_copy_frag intentionally initializes a pointer to array[-1] to increment it later to valid values. clang rightfully generates an array-bounds warning on the initialization statement.
Initialize the pointer to array[0] and change the algorithm from increment before to increment after consume.
Signed-off-by: Matthias Kaehlcke mka@chromium.org Signed-off-by: Johannes Berg johannes.berg@intel.com Cc: Nathan Chancellor natechancellor@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/wireless/util.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -663,7 +663,7 @@ __ieee80211_amsdu_copy_frag(struct sk_bu int offset, int len) { struct skb_shared_info *sh = skb_shinfo(skb); - const skb_frag_t *frag = &sh->frags[-1]; + const skb_frag_t *frag = &sh->frags[0]; struct page *frag_page; void *frag_ptr; int frag_len, frag_size; @@ -676,10 +676,10 @@ __ieee80211_amsdu_copy_frag(struct sk_bu
while (offset >= frag_size) { offset -= frag_size; - frag++; frag_page = skb_frag_page(frag); frag_ptr = skb_frag_address(frag); frag_size = skb_frag_size(frag); + frag++; }
frag_ptr += offset; @@ -691,12 +691,12 @@ __ieee80211_amsdu_copy_frag(struct sk_bu len -= cur_len;
while (len > 0) { - frag++; frag_len = skb_frag_size(frag); cur_len = min(len, frag_len); __frame_add_frag(frame, skb_frag_page(frag), skb_frag_address(frag), cur_len, frag_len); len -= cur_len; + frag++; } }