[PATCH AUTOSEL 4.4 03/14] atm: eni: dont release is never initialized

From: Sasha Levin
Date: Tue Mar 16 2021 - 21:08:01 EST


From: Tong Zhang <ztong0001@xxxxxxxxx>

[ Upstream commit 4deb550bc3b698a1f03d0332cde3df154d1b6c1e ]

label err_eni_release is reachable when eni_start() fail.
In eni_start() it calls dev->phy->start() in the last step, if start()
fail we don't need to call phy->stop(), if start() is never called, we
neither need to call phy->stop(), otherwise null-ptr-deref will happen.

In order to fix this issue, don't call phy->stop() in label err_eni_release

[ 4.875714] ==================================================================
[ 4.876091] BUG: KASAN: null-ptr-deref in suni_stop+0x47/0x100 [suni]
[ 4.876433] Read of size 8 at addr 0000000000000030 by task modprobe/95
[ 4.876778]
[ 4.876862] CPU: 0 PID: 95 Comm: modprobe Not tainted 5.11.0-rc7-00090-gdcc0b49040c7 #2
[ 4.877290] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-48-gd94
[ 4.877876] Call Trace:
[ 4.878009] dump_stack+0x7d/0xa3
[ 4.878191] kasan_report.cold+0x10c/0x10e
[ 4.878410] ? __slab_free+0x2f0/0x340
[ 4.878612] ? suni_stop+0x47/0x100 [suni]
[ 4.878832] suni_stop+0x47/0x100 [suni]
[ 4.879043] eni_do_release+0x3b/0x70 [eni]
[ 4.879269] eni_init_one.cold+0x1152/0x1747 [eni]
[ 4.879528] ? _raw_spin_lock_irqsave+0x7b/0xd0
[ 4.879768] ? eni_ioctl+0x270/0x270 [eni]
[ 4.879990] ? __mutex_lock_slowpath+0x10/0x10
[ 4.880226] ? eni_ioctl+0x270/0x270 [eni]
[ 4.880448] local_pci_probe+0x6f/0xb0
[ 4.880650] pci_device_probe+0x171/0x240
[ 4.880864] ? pci_device_remove+0xe0/0xe0
[ 4.881086] ? kernfs_create_link+0xb6/0x110
[ 4.881315] ? sysfs_do_create_link_sd.isra.0+0x76/0xe0
[ 4.881594] really_probe+0x161/0x420
[ 4.881791] driver_probe_device+0x6d/0xd0
[ 4.882010] device_driver_attach+0x82/0x90
[ 4.882233] ? device_driver_attach+0x90/0x90
[ 4.882465] __driver_attach+0x60/0x100
[ 4.882671] ? device_driver_attach+0x90/0x90
[ 4.882903] bus_for_each_dev+0xe1/0x140
[ 4.883114] ? subsys_dev_iter_exit+0x10/0x10
[ 4.883346] ? klist_node_init+0x61/0x80
[ 4.883557] bus_add_driver+0x254/0x2a0
[ 4.883764] driver_register+0xd3/0x150
[ 4.883971] ? 0xffffffffc0038000
[ 4.884149] do_one_initcall+0x84/0x250
[ 4.884355] ? trace_event_raw_event_initcall_finish+0x150/0x150
[ 4.884674] ? unpoison_range+0xf/0x30
[ 4.884875] ? ____kasan_kmalloc.constprop.0+0x84/0xa0
[ 4.885150] ? unpoison_range+0xf/0x30
[ 4.885352] ? unpoison_range+0xf/0x30
[ 4.885557] do_init_module+0xf8/0x350
[ 4.885760] load_module+0x3fe6/0x4340
[ 4.885960] ? vm_unmap_ram+0x1d0/0x1d0
[ 4.886166] ? ____kasan_kmalloc.constprop.0+0x84/0xa0
[ 4.886441] ? module_frob_arch_sections+0x20/0x20
[ 4.886697] ? __do_sys_finit_module+0x108/0x170
[ 4.886941] __do_sys_finit_module+0x108/0x170
[ 4.887178] ? __ia32_sys_init_module+0x40/0x40
[ 4.887419] ? file_open_root+0x200/0x200
[ 4.887634] ? do_sys_open+0x85/0xe0
[ 4.887826] ? filp_open+0x50/0x50
[ 4.888009] ? fpregs_assert_state_consistent+0x4d/0x60
[ 4.888287] ? exit_to_user_mode_prepare+0x2f/0x130
[ 4.888547] do_syscall_64+0x33/0x40
[ 4.888739] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 4.889010] RIP: 0033:0x7ff62fcf1cf7
[ 4.889202] Code: 48 89 57 30 48 8b 04 24 48 89 47 38 e9 1d a0 02 00 48 89 f8 48 89 f71
[ 4.890172] RSP: 002b:00007ffe6644ade8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 4.890570] RAX: ffffffffffffffda RBX: 0000000000f2ca70 RCX: 00007ff62fcf1cf7
[ 4.890944] RDX: 0000000000000000 RSI: 0000000000f2b9e0 RDI: 0000000000000003
[ 4.891318] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001
[ 4.891691] R10: 00007ff62fd55300 R11: 0000000000000246 R12: 0000000000f2b9e0
[ 4.892064] R13: 0000000000000000 R14: 0000000000f2bdd0 R15: 0000000000000001
[ 4.892439] ==================================================================

Signed-off-by: Tong Zhang <ztong0001@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/atm/eni.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/atm/eni.c b/drivers/atm/eni.c
index 340a1ee79d28..3d5ad2bc809b 100644
--- a/drivers/atm/eni.c
+++ b/drivers/atm/eni.c
@@ -2278,7 +2278,8 @@ static int eni_init_one(struct pci_dev *pci_dev,
return rc;

err_eni_release:
- eni_do_release(dev);
+ dev->phy = NULL;
+ iounmap(ENI_DEV(dev)->ioaddr);
err_unregister:
atm_dev_deregister(dev);
err_free_consistent:
--
2.30.1