From: Johannes Berg <johannes.berg@intel.com> stable inclusion from stable-v4.19.247 commit 9f1e5cc85ad77e52f54049a94db0407445ae2a34 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBP3RV CVE: CVE-2022-49416 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 2965c4cdf7ad9ce0796fac5e57debb9519ea721e upstream. In ieee80211_vif_use_reserved_context(), when we have an old context and the new context's replace_state is set to IEEE80211_CHANCTX_REPLACE_NONE, we free the old context in ieee80211_vif_use_reserved_reassign(). Therefore, we cannot check the old_ctx anymore, so we should set it to NULL after this point. However, since the new_ctx replace state is clearly not IEEE80211_CHANCTX_REPLACES_OTHER, we're not going to do anything else in this function and can just return to avoid accessing the freed old_ctx. Cc: stable@vger.kernel.org Fixes: 5bcae31d9cb1 ("mac80211: implement multi-vif in-place reservations") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20220601091926.df419d91b165.I17a9b3894ff0b8323ce2a... Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Xiangwei Li <liwei728@huawei.com> --- net/mac80211/chan.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index d9558ffb8acf..6d95ce1c4a27 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -1638,12 +1638,9 @@ int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata) if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) { if (old_ctx) - err = ieee80211_vif_use_reserved_reassign(sdata); - else - err = ieee80211_vif_use_reserved_assign(sdata); + return ieee80211_vif_use_reserved_reassign(sdata); - if (err) - return err; + return ieee80211_vif_use_reserved_assign(sdata); } /* -- 2.25.1