remarkable-linux/include/linux/sunrpc/debug.h
Jeff Layton f9c72d10d6 sunrpc: make debugfs file creation failure non-fatal
We currently have a problem that SELinux policy is being enforced when
creating debugfs files. If a debugfs file is created as a side effect of
doing some syscall, then that creation can fail if the SELinux policy
for that process prevents it.

This seems wrong. We don't do that for files under /proc, for instance,
so Bruce has proposed a patch to fix that.

While discussing that patch however, Greg K.H. stated:

    "No kernel code should care / fail if a debugfs function fails, so
     please fix up the sunrpc code first."

This patch converts all of the sunrpc debugfs setup code to be void
return functins, and the callers to not look for errors from those
functions.

This should allow rpc_clnt and rpc_xprt creation to work, even if the
kernel fails to create debugfs files for some reason.

Symptoms were failing krb5 mounts on systems using gss-proxy and
selinux.

Fixes: 388f0c7767 "sunrpc: add a debugfs rpc_xprt directory..."
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-03-31 14:15:08 -04:00

108 lines
2.1 KiB
C

/*
* linux/include/linux/sunrpc/debug.h
*
* Debugging support for sunrpc module
*
* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
*/
#ifndef _LINUX_SUNRPC_DEBUG_H_
#define _LINUX_SUNRPC_DEBUG_H_
#include <uapi/linux/sunrpc/debug.h>
/*
* Debugging macros etc
*/
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
extern unsigned int rpc_debug;
extern unsigned int nfs_debug;
extern unsigned int nfsd_debug;
extern unsigned int nlm_debug;
#endif
#define dprintk(args...) dfprintk(FACILITY, ## args)
#define dprintk_rcu(args...) dfprintk_rcu(FACILITY, ## args)
#undef ifdebug
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define ifdebug(fac) if (unlikely(rpc_debug & RPCDBG_##fac))
# define dfprintk(fac, args...) \
do { \
ifdebug(fac) \
printk(KERN_DEFAULT args); \
} while (0)
# define dfprintk_rcu(fac, args...) \
do { \
ifdebug(fac) { \
rcu_read_lock(); \
printk(KERN_DEFAULT args); \
rcu_read_unlock(); \
} \
} while (0)
# define RPC_IFDEBUG(x) x
#else
# define ifdebug(fac) if (0)
# define dfprintk(fac, args...) do {} while (0)
# define dfprintk_rcu(fac, args...) do {} while (0)
# define RPC_IFDEBUG(x)
#endif
/*
* Sysctl interface for RPC debugging
*/
struct rpc_clnt;
struct rpc_xprt;
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
void rpc_register_sysctl(void);
void rpc_unregister_sysctl(void);
void sunrpc_debugfs_init(void);
void sunrpc_debugfs_exit(void);
void rpc_clnt_debugfs_register(struct rpc_clnt *);
void rpc_clnt_debugfs_unregister(struct rpc_clnt *);
void rpc_xprt_debugfs_register(struct rpc_xprt *);
void rpc_xprt_debugfs_unregister(struct rpc_xprt *);
#else
static inline void
sunrpc_debugfs_init(void)
{
return;
}
static inline void
sunrpc_debugfs_exit(void)
{
return;
}
static inline void
rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
{
return;
}
static inline void
rpc_clnt_debugfs_unregister(struct rpc_clnt *clnt)
{
return;
}
static inline void
rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
{
return;
}
static inline void
rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt)
{
return;
}
#endif
#endif /* _LINUX_SUNRPC_DEBUG_H_ */