On Wed, Feb 22, 2023 at 11:03:01PM +0300, Fedor Pchelkin wrote:
From: Pavel Skripkin paskripkin@gmail.com
commit 8b5cb7e41d9d77ffca036b0239177de123394a55 upstream.
Syzbot hit NULL deref in rhashtable_free_and_destroy(). The problem was in mesh_paths and mpp_paths being NULL.
mesh_pathtbl_init() could fail in case of memory allocation failure, but nobody cared, since ieee80211_mesh_init_sdata() returns void. It led to leaving 2 pointers as NULL. Syzbot has found null deref on exit path, but it could happen anywhere else, because code assumes these pointers are valid.
Since all ieee80211_*_setup_sdata functions are void and do not fail, let's embedd mesh_paths and mpp_paths into parent struct to avoid adding error handling on higher levels and follow the pattern of others setup_sdata functions
Fixes: 60854fd94573 ("mac80211: mesh: convert path table to rhashtable") Reported-and-tested-by: syzbot+860268315ba86ea6b96b@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin paskripkin@gmail.com Link: https://lore.kernel.org/r/20211230195547.23977-1-paskripkin@gmail.com Signed-off-by: Johannes Berg johannes.berg@intel.com [pchelkin@ispras.ru: adapt a comment spell fixing issue] Signed-off-by: Fedor Pchelkin pchelkin@ispras.ru
This also worked for 4.19.y, but not 4.14.y, care to also fix it there?
thanks,
greg k-h