[PATCH 5.13 199/300] SUNRPC: Fix a NULL pointer deref in trace_svc_stats_latency()
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-09-13 14:15:29
Also in:
lkml
Subsystem:
kernel nfsd, sunrpc, and lockd servers, networking [general], nfs, sunrpc, and lockd clients, the rest, tracing · Maintainers:
Chuck Lever, Jeff Layton, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Trond Myklebust, Anna Schumaker, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
From: Chuck Lever <redacted>
[ Upstream commit 5c11720767f70d34357d00a15ba5a0ad052c40fe ]
Some paths through svc_process() leave rqst->rq_procinfo set to
NULL, which triggers a crash if tracing happens to be enabled.
Fixes: 89ff87494c6e ("SUNRPC: Display RPC procedure names instead of proc numbers")
Signed-off-by: Chuck Lever <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/linux/sunrpc/svc.h | 1 +
include/trace/events/sunrpc.h | 8 ++++----
net/sunrpc/svc.c | 15 +++++++++++++++
3 files changed, 20 insertions(+), 4 deletions(-)
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index e91d51ea028b..65185d1e07ea 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h@@ -523,6 +523,7 @@ void svc_wake_up(struct svc_serv *); void svc_reserve(struct svc_rqst *rqstp, int space); struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu); char * svc_print_addr(struct svc_rqst *, char *, size_t); +const char * svc_proc_name(const struct svc_rqst *rqstp); int svc_encode_result_payload(struct svc_rqst *rqstp, unsigned int offset, unsigned int length);
diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h
index d02e01a27b69..87569dbf2fe7 100644
--- a/include/trace/events/sunrpc.h
+++ b/include/trace/events/sunrpc.h@@ -1642,7 +1642,7 @@ TRACE_EVENT(svc_process, __field(u32, vers) __field(u32, proc) __string(service, name) - __string(procedure, rqst->rq_procinfo->pc_name) + __string(procedure, svc_proc_name(rqst)) __string(addr, rqst->rq_xprt ? rqst->rq_xprt->xpt_remotebuf : "(null)") ),
@@ -1652,7 +1652,7 @@ TRACE_EVENT(svc_process, __entry->vers = rqst->rq_vers; __entry->proc = rqst->rq_proc; __assign_str(service, name); - __assign_str(procedure, rqst->rq_procinfo->pc_name); + __assign_str(procedure, svc_proc_name(rqst)); __assign_str(addr, rqst->rq_xprt ? rqst->rq_xprt->xpt_remotebuf : "(null)"); ),
@@ -1918,7 +1918,7 @@ TRACE_EVENT(svc_stats_latency, TP_STRUCT__entry( __field(u32, xid) __field(unsigned long, execute) - __string(procedure, rqst->rq_procinfo->pc_name) + __string(procedure, svc_proc_name(rqst)) __string(addr, rqst->rq_xprt->xpt_remotebuf) ),
@@ -1926,7 +1926,7 @@ TRACE_EVENT(svc_stats_latency, __entry->xid = be32_to_cpu(rqst->rq_xid); __entry->execute = ktime_to_us(ktime_sub(ktime_get(), rqst->rq_stime)); - __assign_str(procedure, rqst->rq_procinfo->pc_name); + __assign_str(procedure, svc_proc_name(rqst)); __assign_str(addr, rqst->rq_xprt->xpt_remotebuf); ),
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 0de918cb3d90..a47e290b0668 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c@@ -1629,6 +1629,21 @@ u32 svc_max_payload(const struct svc_rqst *rqstp) } EXPORT_SYMBOL_GPL(svc_max_payload); +/** + * svc_proc_name - Return RPC procedure name in string form + * @rqstp: svc_rqst to operate on + * + * Return value: + * Pointer to a NUL-terminated string + */ +const char *svc_proc_name(const struct svc_rqst *rqstp) +{ + if (rqstp && rqstp->rq_procinfo) + return rqstp->rq_procinfo->pc_name; + return "unknown"; +} + + /** * svc_encode_result_payload - mark a range of bytes as a result payload * @rqstp: svc_rqst to operate on
--
2.30.2