Bug 458622
| Summary: | improper behavior of rpc.mountd on NFS server leads to BUG on NFS client | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Vasily Averin <vvs> |
| Component: | nfs-utils | Assignee: | Steve Dickson <steved> |
| Status: | CLOSED WONTFIX | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 8 | ||
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2009-01-09 07:52:11 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
The patch posted to the linux-nfs mailing list: Unfortunately, BUG_ON(IS_ROOT(dentry)) can happen inside nfs_follow_mountpoint with NFS running Fedora 8 using a specific setup. https://bugzilla.redhat.com/show_bug.cgi?id=458622 So, the situation should be handled on NFS client gracefully. Signed-off-by: Denis V. Lunev <den> CC: Trond Myklebust <Trond.Myklebust> CC: J. Bruce Fields <bfields> --- fs/nfs/namespace.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c index 66df08d..4f11c13 100644 --- a/fs/nfs/namespace.c +++ b/fs/nfs/namespace.c @@ -105,7 +105,10 @@ static void * nfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd) dprintk("--> nfs_follow_mountpoint()\n"); - BUG_ON(IS_ROOT(dentry)); + err = -ESTALE; + if (IS_ROOT(dentry)) + goto out_err; + dprintk("%s: enter\n", __func__); dput(nd->path.dentry); nd->path.dentry = dget(dentry); I've created a separate bug for RHEL5 NFS client panic https://bugzilla.redhat.com/show_bug.cgi?id=458774 This message is a reminder that Fedora 8 is nearing its end of life. Approximately 30 (thirty) days from now Fedora will stop maintaining and issuing updates for Fedora 8. It is Fedora's policy to close all bug reports from releases that are no longer maintained. At that time this bug will be closed as WONTFIX if it remains open with a Fedora 'version' of '8'. Package Maintainer: If you wish for this bug to remain open because you plan to fix it in a currently maintained version, simply change the 'version' to a later Fedora version prior to Fedora 8's end of life. Bug Reporter: Thank you for reporting this issue and we are sorry that we may not be able to fix it before Fedora 8 is end of life. If you would still like to see this bug fixed and are able to reproduce it against a later version of Fedora please change the 'version' of this bug to the applicable version. If you are unable to change the version, please add a comment here and someone will do it for you. Although we aim to fix as many bugs as possible during every release's lifetime, sometimes those efforts are overtaken by events. Often a more recent Fedora release includes newer upstream software that fixes bugs or makes them obsolete. The process we are following is described here: http://fedoraproject.org/wiki/BugZappers/HouseKeeping Fedora 8 changed to end-of-life (EOL) status on 2009-01-07. Fedora 8 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. Thank you for reporting this bug and we are sorry it could not be fixed. |
Description of problem: Specific NFS server setup results on BUG on linux nfs client: nfs_follow_mountpoint BUG_ON(IS_ROOT(dentry)) the configuration is the following: tc27.qa.sw.ru -- NFS server (FC8) ts27.qa.sw.ru -- NFS client (RHEL5) Server configuration is the following: [root@tc27 proc]# cat /etc/exports /nfs_share ts27.qa.sw.ru(rw,no_root_squash,no_subtree_check,crossmnt) /nfs_share/boo *(rw,no_root_squash,no_subtree_check) [root@tc27 proc]# cat /proc/mounts /dev/mapper/vzvg-vz /nfs_share ext3 rw,data=ordered 0 0 /dev/sda1 /nfs_share/boo ext3 rw,data=ordered 0 0 Issue can be reproduced by the following script on CLIENT SIDE: [root@ts27 ~]# cat sub-mounts.sh #!/bin/bash echo 65535 > /proc/sys/sunrpc/nfs_debug echo 65535 > /proc/sys/sunrpc/rpc_debug stat -f /mnt/nfs/ | grep -q 'Type: nfs' || mount -v -t nfs tc27:/nfs_share /mnt/nfs -o vers=3,tcp,hard,nointr { ls /mnt/nfs ls /mnt/nfs/boo } >/dev/null echo =========================== grep nfs /proc/mounts umount /mnt/nfs/ This BUG_ON happens due to improper behavior of rpc.mountd process on the nfs server. This is proven by the following file on the server: [root@tc27 proc]# cat /proc/net/rpc/nfsd.fh/content #domain fsidtype fsid [path] *,ts27 0 0x0000fd0000000002 /nfs_share *,ts27 0 0x0100080000000002 /nfs_share As you can see it contains /nfs_share instead of /nfs_share/boo for 0x0100080000000002 fsid. Version-Release number of selected component (if applicable): nfs-utils-1.1.0-6.fc8 Actual results: BUG_ON on client side on nfs submount lookup because of incorrect content of /proc/net/rpc/nfsd.fh/content file Expected results: correct content of /proc/net/rpc/nfsd.fh/content file