From 05c5d5c75b6e30af9b00ecd07eb9f2733741e8df Mon Sep 17 00:00:00 2001 From: Kinglong Mee Date: Sat, 15 Aug 2015 21:52:10 +0800 Subject: [PATCH] NFS: Fix a NULL pointer dereference of migration recovery ops for v4.2 client commit 18e3b739fdc826481c6a1335ce0c5b19b3d415da upstream. ---Steps to Reproduce-- # cat /etc/exports /nfs/referal *(rw,insecure,no_subtree_check,no_root_squash,crossmnt) /nfs/old *(ro,insecure,subtree_check,root_squash,crossmnt) # mount -t nfs nfs-server:/nfs/ /mnt/ # ll /mnt/*/ # cat /etc/exports /nfs/referal *(rw,insecure,no_subtree_check,no_root_squash,crossmnt,refer=/nfs/old/@nfs-server) /nfs/old *(ro,insecure,subtree_check,root_squash,crossmnt) # service nfs restart # ll /mnt/*/ --->>>>> oops here [ 5123.102925] BUG: unable to handle kernel NULL pointer dereference at (null) [ 5123.103363] IP: [] nfs4_proc_get_locations+0x9b/0x120 [nfsv4] [ 5123.103752] PGD 587b9067 PUD 3cbf5067 PMD 0 [ 5123.104131] Oops: 0000 [#1] [ 5123.104529] Modules linked in: nfsv4(OE) nfs(OE) fscache(E) nfsd(OE) xfs libcrc32c iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi coretemp crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ppdev vmw_balloon parport_pc parport i2c_piix4 shpchp auth_rpcgss nfs_acl vmw_vmci lockd grace sunrpc vmwgfx drm_kms_helper ttm drm mptspi serio_raw scsi_transport_spi e1000 mptscsih mptbase ata_generic pata_acpi [last unloaded: nfsd] [ 5123.105887] CPU: 0 PID: 15853 Comm: ::1-manager Tainted: G OE 4.2.0-rc6+ #214 [ 5123.106358] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014 [ 5123.106860] task: ffff88007620f300 ti: ffff88005877c000 task.ti: ffff88005877c000 [ 5123.107363] RIP: 0010:[] [] nfs4_proc_get_locations+0x9b/0x120 [nfsv4] [ 5123.107909] RSP: 0018:ffff88005877fdb8 EFLAGS: 00010246 [ 5123.108435] RAX: ffff880053f3bc00 RBX: ffff88006ce6c908 RCX: ffff880053a0d240 [ 5123.108968] RDX: ffffea0000e6d940 RSI: ffff8800399a0000 RDI: ffff88006ce6c908 [ 5123.109503] RBP: ffff88005877fe28 R08: ffffffff81c708a0 R09: 0000000000000000 [ 5123.110045] R10: 00000000000001a2 R11: ffff88003ba7f5c8 R12: ffff880054c55800 [ 5123.110618] R13: 0000000000000000 R14: ffff880053a0d240 R15: ffff880053a0d240 [ 5123.111169] FS: 0000000000000000(0000) GS:ffffffff81c27000(0000) knlGS:0000000000000000 [ 5123.111726] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 5123.112286] CR2: 0000000000000000 CR3: 0000000054cac000 CR4: 00000000001406f0 [ 5123.112888] Stack: [ 5123.113458] ffffea0000e6d940 ffff8800399a0000 00000000000167d0 0000000000000000 [ 5123.114049] 0000000000000000 0000000000000000 0000000000000000 00000000a7ec82c6 [ 5123.114662] ffff88005877fe18 ffffea0000e6d940 ffff8800399a0000 ffff880054c55800 [ 5123.115264] Call Trace: [ 5123.115868] [] nfs4_try_migration+0xbb/0x220 [nfsv4] [ 5123.116487] [] nfs4_run_state_manager+0x4ab/0x7b0 [nfsv4] [ 5123.117104] [] ? nfs4_do_reclaim+0x510/0x510 [nfsv4] [ 5123.117813] [] kthread+0xd7/0xf0 [ 5123.118456] [] ? kthread_worker_fn+0x160/0x160 [ 5123.119108] [] ret_from_fork+0x3f/0x70 [ 5123.119723] [] ? kthread_worker_fn+0x160/0x160 [ 5123.120329] Code: 4c 8b 6a 58 74 17 eb 52 48 8d 55 a8 89 c6 4c 89 e7 e8 4a b5 ff ff 8b 45 b0 85 c0 74 1c 4c 89 f9 48 8b 55 90 48 8b 75 98 48 89 df <41> ff 55 00 3d e8 d8 ff ff 41 89 c6 74 cf 48 8b 4d c8 65 48 33 [ 5123.121643] RIP [] nfs4_proc_get_locations+0x9b/0x120 [nfsv4] [ 5123.122308] RSP [ 5123.122942] CR2: 0000000000000000 Fixes: ec011fe847 ("NFS: Introduce a vector of migration recovery ops") Signed-off-by: Kinglong Mee Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- fs/nfs/nfs4proc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index fcdab78d0df7f4..7b945957e230dc 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -8368,6 +8368,7 @@ static const struct nfs4_minor_version_ops nfs_v4_2_minor_ops = { .reboot_recovery_ops = &nfs41_reboot_recovery_ops, .nograce_recovery_ops = &nfs41_nograce_recovery_ops, .state_renewal_ops = &nfs41_state_renewal_ops, + .mig_recovery_ops = &nfs41_mig_recovery_ops, }; #endif