This is a note to let you know that I've just added the patch titled
nfsd: fix oops when reading pool_stats before server is started
to the 6.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfsd-fix-oops-when-reading-pool_stats-before-server-.patch
and it can be found in the queue-6.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 388a527c6cf55bde74bc0891d0b4c38f50d896be
Author: Jeff Layton <jlayton@xxxxxxxxxx>
Date: Mon Jun 17 07:54:08 2024 -0400
nfsd: fix oops when reading pool_stats before server is started
[ Upstream commit 8e948c365d9c10b685d1deb946bd833d6a9b43e0 ]
Sourbh reported an oops that is triggerable by trying to read the
pool_stats procfile before nfsd had been started. Move the check for a
NULL serv in svc_pool_stats_start above the mutex acquisition, and fix
the stop routine not to unlock the mutex if there is no serv yet.
Fixes: 7b207ccd9833 ("svc: don't hold reference for poolstats, only mutex.")
Reported-by: Sourabh Jain <sourabhjain@xxxxxxxxxxxxx>
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Tested-by: Sourabh Jain <sourabhjain@xxxxxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index b4a85a227bd7d..1a2982051f986 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -1371,12 +1371,13 @@ static void *svc_pool_stats_start(struct seq_file *m, loff_t *pos)
dprintk("svc_pool_stats_start, *pidx=%u\n", pidx);
+ if (!si->serv)
+ return NULL;
+
mutex_lock(si->mutex);
if (!pidx)
return SEQ_START_TOKEN;
- if (!si->serv)
- return NULL;
return pidx > si->serv->sv_nrpools ? NULL
: &si->serv->sv_pools[pidx - 1];
}
@@ -1408,7 +1409,8 @@ static void svc_pool_stats_stop(struct seq_file *m, void *p)
{
struct svc_info *si = m->private;
- mutex_unlock(si->mutex);
+ if (si->serv)
+ mutex_unlock(si->mutex);
}
static int svc_pool_stats_show(struct seq_file *m, void *p)
