| Message ID | 20201204162428.2583119-1-eric.dumazet@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [net] mac80211: mesh: fix mesh_pathtbl_init() error path | expand |
On Fri, 2020-12-04 at 08:24 -0800, Eric Dumazet wrote: > From: Eric Dumazet <edumazet@google.com> > > If tbl_mpp can not be allocated, we call mesh_table_free(tbl_path) > while tbl_path rhashtable has not yet been initialized, which causes > panics. Thanks Eric! I was going to ask how you ran into this ... > Reported-by: syzbot <syzkaller@googlegroups.com> Until I saw this - but doesn't syzbot normally want a "syzbot+somehashid@..." as the reported-by? > --- a/net/mac80211/mesh_pathtbl.c > +++ b/net/mac80211/mesh_pathtbl.c > @@ -60,6 +60,7 @@ static struct mesh_table *mesh_table_alloc(void) > atomic_set(&newtbl->entries, 0); > spin_lock_init(&newtbl->gates_lock); > spin_lock_init(&newtbl->walk_lock); > + rhashtable_init(&newtbl->rhead, &mesh_rht_params); > > return newtbl; > } > @@ -773,9 +774,6 @@ int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata) > goto free_path; > } > > - rhashtable_init(&tbl_path->rhead, &mesh_rht_params); > - rhashtable_init(&tbl_mpp->rhead, &mesh_rht_params); > Hmm. There were two calls, now there's only one? Is that a bug, or am I missing something? johannes
On Fri, 2020-12-04 at 17:26 +0100, Johannes Berg wrote: > On Fri, 2020-12-04 at 08:24 -0800, Eric Dumazet wrote: > > From: Eric Dumazet <edumazet@google.com> > > > > If tbl_mpp can not be allocated, we call mesh_table_free(tbl_path) > > while tbl_path rhashtable has not yet been initialized, which causes > > panics. > > Thanks Eric! > > I was going to ask how you ran into this ... > > > Reported-by: syzbot <syzkaller@googlegroups.com> > > Until I saw this - but doesn't syzbot normally want a > "syzbot+somehashid@..." as the reported-by? > > > > --- a/net/mac80211/mesh_pathtbl.c > > +++ b/net/mac80211/mesh_pathtbl.c > > @@ -60,6 +60,7 @@ static struct mesh_table *mesh_table_alloc(void) > > atomic_set(&newtbl->entries, 0); > > spin_lock_init(&newtbl->gates_lock); > > spin_lock_init(&newtbl->walk_lock); > > + rhashtable_init(&newtbl->rhead, &mesh_rht_params); > > > > return newtbl; > > } > > @@ -773,9 +774,6 @@ int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata) > > goto free_path; > > } > > > > - rhashtable_init(&tbl_path->rhead, &mesh_rht_params); > > - rhashtable_init(&tbl_mpp->rhead, &mesh_rht_params); > > > > Hmm. There were two calls, now there's only one? Is that a bug, or am I > missing something? Umm, never mind. johannes
On Fri, 2020-12-04 at 08:24 -0800, Eric Dumazet wrote: > From: Eric Dumazet <edumazet@google.com> > > If tbl_mpp can not be allocated, we call mesh_table_free(tbl_path) > while tbl_path rhashtable has not yet been initialized, which causes > panics. > > Simply factorize the rhashtable_init() call into mesh_table_alloc() > > WARNING: CPU: 1 PID: 8474 at kernel/workqueue.c:3040 __flush_work kernel/workqueue.c:3040 [inline] > WARNING: CPU: 1 PID: 8474 at kernel/workqueue.c:3040 __cancel_work_timer+0x514/0x540 kernel/workqueue.c:3136 > Modules linked in: > CPU: 1 PID: 8474 Comm: syz-executor663 Not tainted 5.10.0-rc6-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > RIP: 0010:__flush_work kernel/workqueue.c:3040 [inline] > RIP: 0010:__cancel_work_timer+0x514/0x540 kernel/workqueue.c:3136 > Code: 5d c3 e8 bf ae 29 00 0f 0b e9 f0 fd ff ff e8 b3 ae 29 00 0f 0b 43 80 3c 3e 00 0f 85 31 ff ff ff e9 34 ff ff ff e8 9c ae 29 00 <0f> 0b e9 dc fe ff ff 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c 7d fd ff > RSP: 0018:ffffc9000165f5a0 EFLAGS: 00010293 > RAX: ffffffff814b7064 RBX: 0000000000000001 RCX: ffff888021c80000 > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: ffff888024039ca0 R08: dffffc0000000000 R09: fffffbfff1dd3e64 > R10: fffffbfff1dd3e64 R11: 0000000000000000 R12: 1ffff920002cbebd > R13: ffff888024039c88 R14: 1ffff11004807391 R15: dffffc0000000000 > FS: 0000000001347880(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000140 CR3: 000000002cc0a000 CR4: 00000000001506e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > rhashtable_free_and_destroy+0x25/0x9c0 lib/rhashtable.c:1137 > mesh_table_free net/mac80211/mesh_pathtbl.c:69 [inline] > mesh_pathtbl_init+0x287/0x2e0 net/mac80211/mesh_pathtbl.c:785 > ieee80211_mesh_init_sdata+0x2ee/0x530 net/mac80211/mesh.c:1591 > ieee80211_setup_sdata+0x733/0xc40 net/mac80211/iface.c:1569 > ieee80211_if_add+0xd5c/0x1cd0 net/mac80211/iface.c:1987 > ieee80211_add_iface+0x59/0x130 net/mac80211/cfg.c:125 > rdev_add_virtual_intf net/wireless/rdev-ops.h:45 [inline] > nl80211_new_interface+0x563/0xb40 net/wireless/nl80211.c:3855 > genl_family_rcv_msg_doit net/netlink/genetlink.c:739 [inline] > genl_family_rcv_msg net/netlink/genetlink.c:783 [inline] > genl_rcv_msg+0xe4e/0x1280 net/netlink/genetlink.c:800 > netlink_rcv_skb+0x190/0x3a0 net/netlink/af_netlink.c:2494 > genl_rcv+0x24/0x40 net/netlink/genetlink.c:811 > netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] > netlink_unicast+0x780/0x930 net/netlink/af_netlink.c:1330 > netlink_sendmsg+0x9a8/0xd40 net/netlink/af_netlink.c:1919 > sock_sendmsg_nosec net/socket.c:651 [inline] > sock_sendmsg net/socket.c:671 [inline] > ____sys_sendmsg+0x519/0x800 net/socket.c:2353 > ___sys_sendmsg net/socket.c:2407 [inline] > __sys_sendmsg+0x2b1/0x360 net/socket.c:2440 > do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Fixes: 60854fd94573 ("mac80211: mesh: convert path table to rhashtable") > Signed-off-by: Eric Dumazet <edumazet@google.com> > Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Jakub, if you want to take it to the net tree I wouldn't mind at all, since I _just_ sent a pull request a little while ago. Thanks, johannes
On Fri, Dec 4, 2020 at 5:26 PM Johannes Berg <johannes@sipsolutions.net> wrote: > > On Fri, 2020-12-04 at 08:24 -0800, Eric Dumazet wrote: > > From: Eric Dumazet <edumazet@google.com> > > > > If tbl_mpp can not be allocated, we call mesh_table_free(tbl_path) > > while tbl_path rhashtable has not yet been initialized, which causes > > panics. > > Thanks Eric! > > I was going to ask how you ran into this ... > > > Reported-by: syzbot <syzkaller@googlegroups.com> > > Until I saw this - but doesn't syzbot normally want a > "syzbot+somehashid@..." as the reported-by? Do not worry about this, I will not release the syzbot publicly, no need to add more noise to various mailing lists for such a trivial patch. (This particular syzbot report included yet a buggy bisection, lets not get yet another replies from annoyed developers ) This is why we add a Reported-by: syzbot <syzkaller@googlegroups.com>, only to let the syzbot teams count the number of syzbot bugs fixed.
On Fri, 04 Dec 2020 17:29:39 +0100 Johannes Berg wrote: > On Fri, 2020-12-04 at 08:24 -0800, Eric Dumazet wrote: > > From: Eric Dumazet <edumazet@google.com> > > > > If tbl_mpp can not be allocated, we call mesh_table_free(tbl_path) > > while tbl_path rhashtable has not yet been initialized, which causes > > panics. > > > > Simply factorize the rhashtable_init() call into mesh_table_alloc() > > Fixes: 60854fd94573 ("mac80211: mesh: convert path table to rhashtable") > > Signed-off-by: Eric Dumazet <edumazet@google.com> > > Reported-by: syzbot <syzkaller@googlegroups.com> > > Reviewed-by: Johannes Berg <johannes@sipsolutions.net> > > Jakub, if you want to take it to the net tree I wouldn't mind at all, > since I _just_ sent a pull request a little while ago. Sure thing. Applied, thanks!
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c index 48f31ac9233c8b33558cf41a9b44412c7b1ad591..620ecf922408b1f870d4da8ab7eef02e4d33ab15 100644 --- a/net/mac80211/mesh_pathtbl.c +++ b/net/mac80211/mesh_pathtbl.c @@ -60,6 +60,7 @@ static struct mesh_table *mesh_table_alloc(void) atomic_set(&newtbl->entries, 0); spin_lock_init(&newtbl->gates_lock); spin_lock_init(&newtbl->walk_lock); + rhashtable_init(&newtbl->rhead, &mesh_rht_params); return newtbl; } @@ -773,9 +774,6 @@ int mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata) goto free_path; } - rhashtable_init(&tbl_path->rhead, &mesh_rht_params); - rhashtable_init(&tbl_mpp->rhead, &mesh_rht_params); - sdata->u.mesh.mesh_paths = tbl_path; sdata->u.mesh.mpp_paths = tbl_mpp;