[PATCH AUTOSEL 4.9 02/21] rsi: improve kernel thread handling to fix kernel panic

[PATCH AUTOSEL 4.9 02/21] rsi: improve kernel thread handling to fix kernel panic

[Sasha Levin]

From: Siva Rebbagondla <siva.rebbagondla@redpinesignals.com>

[ Upstream commit 4c62764d0fc21a34ffc44eec1210038c3a2e4473 ]

While running regressions, observed below kernel panic when sdio disconnect
called. This is because of, kthread_stop() is taking care of
wait_for_completion() by default. When wait_for_completion triggered
in kthread_stop and as it was done already, giving kernel panic.
Hence, removing redundant wait_for_completion() from rsi_kill_thread().

... skipping ...
BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff810a63df>] exit_creds+0x1f/0x50
PGD 0
Oops: 0002 [#1] SMP
CPU: 0 PID: 6502 Comm: rmmod Tainted: G  OE   4.15.9-Generic #154-Ubuntu
Hardware name: Dell Inc. Edge Gateway 3003/ , BIOS 01.00.00 04/17/2017
Stack:
ffff88007392e600 ffff880075847dc0 ffffffff8108160a 0000000000000000
ffff88007392e600 ffff880075847de8 ffffffff810a484b ffff880076127000
ffff88003cd3a800 ffff880074f12a00 ffff880075847e28 ffffffffc09bed15
Call Trace:
[<ffffffff8108160a>] __put_task_struct+0x5a/0x140
[<ffffffff810a484b>] kthread_stop+0x10b/0x110
[<ffffffffc09bed15>] rsi_disconnect+0x2f5/0x300 [ven_rsi_sdio]
[<ffffffff81578bcb>] ? __pm_runtime_resume+0x5b/0x80
[<ffffffff816f0918>] sdio_bus_remove+0x38/0x100
[<ffffffff8156cc64>] __device_release_driver+0xa4/0x150
[<ffffffff8156d7a5>] driver_detach+0xb5/0xc0
[<ffffffff8156c6c5>] bus_remove_driver+0x55/0xd0
[<ffffffff8156dfbc>] driver_unregister+0x2c/0x50
[<ffffffff816f0b8a>] sdio_unregister_driver+0x1a/0x20
[<ffffffffc09bf0f5>] rsi_module_exit+0x15/0x30 [ven_rsi_sdio]
[<ffffffff8110cad8>] SyS_delete_module+0x1b8/0x210
[<ffffffff81851dc8>] entry_SYSCALL_64_fastpath+0x1c/0xbb

Signed-off-by: Siva Rebbagondla <siva.rebbagondla@redpinesignals.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/wireless/rsi/rsi_common.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/net/wireless/rsi/rsi_common.h b/drivers/net/wireless/rsi/rsi_common.h
index d3fbe33d2324..a13f08fd8690 100644
--- a/drivers/net/wireless/rsi/rsi_common.h
+++ b/drivers/net/wireless/rsi/rsi_common.h
@@ -75,7 +75,6 @@ static inline int rsi_kill_thread(struct rsi_thread *handle)
 	atomic_inc(&handle->thread_done);
 	rsi_set_event(&handle->event);
 
-	wait_for_completion(&handle->completion);
 	return kthread_stop(handle->task);
 }
 
-- 
2.19.1

[PATCH AUTOSEL 4.9 03/21] 9p: do not trust pdu content for stat item size

[Sasha Levin]

From: Gertjan Halkes <gertjan@google.com>

[ Upstream commit 2803cf4379ed252894f046cb8812a48db35294e3 ]

v9fs_dir_readdir() could deadloop if a struct was sent with a size set
to -2

Link: http://lkml.kernel.org/r/1536134432-11997-1-git-send-email-asmadeus@codewreck.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88021
Signed-off-by: Gertjan Halkes <gertjan@google.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/9p/vfs_dir.c   | 8 +++-----
 net/9p/protocol.c | 3 ++-
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
index 48db9a9f13f9..cb6c4031af55 100644
--- a/fs/9p/vfs_dir.c
+++ b/fs/9p/vfs_dir.c
@@ -105,7 +105,6 @@ static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
 	int err = 0;
 	struct p9_fid *fid;
 	int buflen;
-	int reclen = 0;
 	struct p9_rdir *rdir;
 	struct kvec kvec;
 
@@ -138,11 +137,10 @@ static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
 		while (rdir->head < rdir->tail) {
 			err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
 					  rdir->tail - rdir->head, &st);
-			if (err) {
+			if (err <= 0) {
 				p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
 				return -EIO;
 			}
-			reclen = st.size+2;
 
 			over = !dir_emit(ctx, st.name, strlen(st.name),
 					 v9fs_qid2ino(&st.qid), dt_type(&st));
@@ -150,8 +148,8 @@ static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
 			if (over)
 				return 0;
 
-			rdir->head += reclen;
-			ctx->pos += reclen;
+			rdir->head += err;
+			ctx->pos += err;
 		}
 	}
 }
diff --git a/net/9p/protocol.c b/net/9p/protocol.c
index 145f80518064..7f1b45c082c9 100644
--- a/net/9p/protocol.c
+++ b/net/9p/protocol.c
@@ -570,9 +570,10 @@ int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st)
 	if (ret) {
 		p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
 		trace_9p_protocol_dump(clnt, &fake_pdu);
+		return ret;
 	}
 
-	return ret;
+	return fake_pdu.offset;
 }
 EXPORT_SYMBOL(p9stat_read);
 
-- 
2.19.1

[PATCH AUTOSEL 4.9 19/21] appletalk: Fix use-after-free in atalk_proc_exit

[Sasha Levin]

From: YueHaibing <yuehaibing@huawei.com>

[ Upstream commit 6377f787aeb945cae7abbb6474798de129e1f3ac ]

KASAN report this:

BUG: KASAN: use-after-free in pde_subdir_find+0x12d/0x150 fs/proc/generic.c:71
Read of size 8 at addr ffff8881f41fe5b0 by task syz-executor.0/2806

CPU: 0 PID: 2806 Comm: syz-executor.0 Not tainted 5.0.0-rc7+ #45
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xfa/0x1ce lib/dump_stack.c:113
 print_address_description+0x65/0x270 mm/kasan/report.c:187
 kasan_report+0x149/0x18d mm/kasan/report.c:317
 pde_subdir_find+0x12d/0x150 fs/proc/generic.c:71
 remove_proc_entry+0xe8/0x420 fs/proc/generic.c:667
 atalk_proc_exit+0x18/0x820 [appletalk]
 atalk_exit+0xf/0x5a [appletalk]
 __do_sys_delete_module kernel/module.c:1018 [inline]
 __se_sys_delete_module kernel/module.c:961 [inline]
 __x64_sys_delete_module+0x3dc/0x5e0 kernel/module.c:961
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x462e99
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb2de6b9c58 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200001c0
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb2de6ba6bc
R13: 00000000004bccaa R14: 00000000006f6bc8 R15: 00000000ffffffff

Allocated by task 2806:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc.constprop.3+0xa0/0xd0 mm/kasan/common.c:496
 slab_post_alloc_hook mm/slab.h:444 [inline]
 slab_alloc_node mm/slub.c:2739 [inline]
 slab_alloc mm/slub.c:2747 [inline]
 kmem_cache_alloc+0xcf/0x250 mm/slub.c:2752
 kmem_cache_zalloc include/linux/slab.h:730 [inline]
 __proc_create+0x30f/0xa20 fs/proc/generic.c:408
 proc_mkdir_data+0x47/0x190 fs/proc/generic.c:469
 0xffffffffc10c01bb
 0xffffffffc10c0166
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 2806:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:458
 slab_free_hook mm/slub.c:1409 [inline]
 slab_free_freelist_hook mm/slub.c:1436 [inline]
 slab_free mm/slub.c:2986 [inline]
 kmem_cache_free+0xa6/0x2a0 mm/slub.c:3002
 pde_put+0x6e/0x80 fs/proc/generic.c:647
 remove_proc_entry+0x1d3/0x420 fs/proc/generic.c:684
 0xffffffffc10c031c
 0xffffffffc10c0166
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881f41fe500
 which belongs to the cache proc_dir_entry of size 256
The buggy address is located 176 bytes inside of
 256-byte region [ffff8881f41fe500, ffff8881f41fe600)
The buggy address belongs to the page:
page:ffffea0007d07f80 count:1 mapcount:0 mapping:ffff8881f6e69a00 index:0x0
flags: 0x2fffc0000000200(slab)
raw: 02fffc0000000200 dead000000000100 dead000000000200 ffff8881f6e69a00
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881f41fe480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8881f41fe500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881f41fe580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff8881f41fe600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8881f41fe680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

It should check the return value of atalk_proc_init fails,
otherwise atalk_exit will trgger use-after-free in pde_subdir_find
while unload the module.This patch fix error cleanup path of atalk_init

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/linux/atalk.h            |  2 +-
 net/appletalk/atalk_proc.c       |  2 +-
 net/appletalk/ddp.c              | 37 ++++++++++++++++++++++++++------
 net/appletalk/sysctl_net_atalk.c |  5 ++++-
 4 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/include/linux/atalk.h b/include/linux/atalk.h
index 73fd8b7e9534..716d53799d1f 100644
--- a/include/linux/atalk.h
+++ b/include/linux/atalk.h
@@ -150,7 +150,7 @@ extern int sysctl_aarp_retransmit_limit;
 extern int sysctl_aarp_resolve_time;
 
 #ifdef CONFIG_SYSCTL
-extern void atalk_register_sysctl(void);
+extern int atalk_register_sysctl(void);
 extern void atalk_unregister_sysctl(void);
 #else
 #define atalk_register_sysctl()		do { } while(0)
diff --git a/net/appletalk/atalk_proc.c b/net/appletalk/atalk_proc.c
index af46bc49e1e9..b5f84f428aa6 100644
--- a/net/appletalk/atalk_proc.c
+++ b/net/appletalk/atalk_proc.c
@@ -293,7 +293,7 @@ int __init atalk_proc_init(void)
 	goto out;
 }
 
-void __exit atalk_proc_exit(void)
+void atalk_proc_exit(void)
 {
 	remove_proc_entry("interface", atalk_proc_dir);
 	remove_proc_entry("route", atalk_proc_dir);
diff --git a/net/appletalk/ddp.c b/net/appletalk/ddp.c
index 10d2bdce686e..e206d98b3b82 100644
--- a/net/appletalk/ddp.c
+++ b/net/appletalk/ddp.c
@@ -1912,12 +1912,16 @@ static const char atalk_err_snap[] __initconst =
 /* Called by proto.c on kernel start up */
 static int __init atalk_init(void)
 {
-	int rc = proto_register(&ddp_proto, 0);
+	int rc;
 
-	if (rc != 0)
+	rc = proto_register(&ddp_proto, 0);
+	if (rc)
 		goto out;
 
-	(void)sock_register(&atalk_family_ops);
+	rc = sock_register(&atalk_family_ops);
+	if (rc)
+		goto out_proto;
+
 	ddp_dl = register_snap_client(ddp_snap_id, atalk_rcv);
 	if (!ddp_dl)
 		printk(atalk_err_snap);
@@ -1925,12 +1929,33 @@ static int __init atalk_init(void)
 	dev_add_pack(&ltalk_packet_type);
 	dev_add_pack(&ppptalk_packet_type);
 
-	register_netdevice_notifier(&ddp_notifier);
+	rc = register_netdevice_notifier(&ddp_notifier);
+	if (rc)
+		goto out_sock;
+
 	aarp_proto_init();
-	atalk_proc_init();
-	atalk_register_sysctl();
+	rc = atalk_proc_init();
+	if (rc)
+		goto out_aarp;
+
+	rc = atalk_register_sysctl();
+	if (rc)
+		goto out_proc;
 out:
 	return rc;
+out_proc:
+	atalk_proc_exit();
+out_aarp:
+	aarp_cleanup_module();
+	unregister_netdevice_notifier(&ddp_notifier);
+out_sock:
+	dev_remove_pack(&ppptalk_packet_type);
+	dev_remove_pack(&ltalk_packet_type);
+	unregister_snap_client(ddp_dl);
+	sock_unregister(PF_APPLETALK);
+out_proto:
+	proto_unregister(&ddp_proto);
+	goto out;
 }
 module_init(atalk_init);
 
diff --git a/net/appletalk/sysctl_net_atalk.c b/net/appletalk/sysctl_net_atalk.c
index ebb864361f7a..4e6042e0fcac 100644
--- a/net/appletalk/sysctl_net_atalk.c
+++ b/net/appletalk/sysctl_net_atalk.c
@@ -44,9 +44,12 @@ static struct ctl_table atalk_table[] = {
 
 static struct ctl_table_header *atalk_table_header;
 
-void atalk_register_sysctl(void)
+int __init atalk_register_sysctl(void)
 {
 	atalk_table_header = register_net_sysctl(&init_net, "net/appletalk", atalk_table);
+	if (!atalk_table_header)
+		return -ENOMEM;
+	return 0;
 }
 
 void atalk_unregister_sysctl(void)
-- 
2.19.1