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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /fs/nfs/cache_lib.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'fs/nfs/cache_lib.c')
-rw-r--r--fs/nfs/cache_lib.c158
1 files changed, 158 insertions, 0 deletions
diff --git a/fs/nfs/cache_lib.c b/fs/nfs/cache_lib.c
new file mode 100644
index 000000000..9738a1ae9
--- /dev/null
+++ b/fs/nfs/cache_lib.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/nfs/cache_lib.c
+ *
+ * Helper routines for the NFS client caches
+ *
+ * Copyright (c) 2009 Trond Myklebust <Trond.Myklebust@netapp.com>
+ */
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/slab.h>
+#include <linux/sunrpc/cache.h>
+#include <linux/sunrpc/rpc_pipe_fs.h>
+#include <net/net_namespace.h>
+
+#include "cache_lib.h"
+
+#define NFS_CACHE_UPCALL_PATHLEN 256
+#define NFS_CACHE_UPCALL_TIMEOUT 15
+
+static char nfs_cache_getent_prog[NFS_CACHE_UPCALL_PATHLEN] =
+ "/sbin/nfs_cache_getent";
+static unsigned long nfs_cache_getent_timeout = NFS_CACHE_UPCALL_TIMEOUT;
+
+module_param_string(cache_getent, nfs_cache_getent_prog,
+ sizeof(nfs_cache_getent_prog), 0600);
+MODULE_PARM_DESC(cache_getent, "Path to the client cache upcall program");
+module_param_named(cache_getent_timeout, nfs_cache_getent_timeout, ulong, 0600);
+MODULE_PARM_DESC(cache_getent_timeout, "Timeout (in seconds) after which "
+ "the cache upcall is assumed to have failed");
+
+int nfs_cache_upcall(struct cache_detail *cd, char *entry_name)
+{
+ static char *envp[] = { "HOME=/",
+ "TERM=linux",
+ "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
+ NULL
+ };
+ char *argv[] = {
+ nfs_cache_getent_prog,
+ cd->name,
+ entry_name,
+ NULL
+ };
+ int ret = -EACCES;
+
+ if (nfs_cache_getent_prog[0] == '\0')
+ goto out;
+ ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
+ /*
+ * Disable the upcall mechanism if we're getting an ENOENT or
+ * EACCES error. The admin can re-enable it on the fly by using
+ * sysfs to set the 'cache_getent' parameter once the problem
+ * has been fixed.
+ */
+ if (ret == -ENOENT || ret == -EACCES)
+ nfs_cache_getent_prog[0] = '\0';
+out:
+ return ret > 0 ? 0 : ret;
+}
+
+/*
+ * Deferred request handling
+ */
+void nfs_cache_defer_req_put(struct nfs_cache_defer_req *dreq)
+{
+ if (refcount_dec_and_test(&dreq->count))
+ kfree(dreq);
+}
+
+static void nfs_dns_cache_revisit(struct cache_deferred_req *d, int toomany)
+{
+ struct nfs_cache_defer_req *dreq;
+
+ dreq = container_of(d, struct nfs_cache_defer_req, deferred_req);
+
+ complete(&dreq->completion);
+ nfs_cache_defer_req_put(dreq);
+}
+
+static struct cache_deferred_req *nfs_dns_cache_defer(struct cache_req *req)
+{
+ struct nfs_cache_defer_req *dreq;
+
+ dreq = container_of(req, struct nfs_cache_defer_req, req);
+ dreq->deferred_req.revisit = nfs_dns_cache_revisit;
+ refcount_inc(&dreq->count);
+
+ return &dreq->deferred_req;
+}
+
+struct nfs_cache_defer_req *nfs_cache_defer_req_alloc(void)
+{
+ struct nfs_cache_defer_req *dreq;
+
+ dreq = kzalloc_obj(*dreq);
+ if (dreq) {
+ init_completion(&dreq->completion);
+ refcount_set(&dreq->count, 1);
+ dreq->req.defer = nfs_dns_cache_defer;
+ }
+ return dreq;
+}
+
+int nfs_cache_wait_for_upcall(struct nfs_cache_defer_req *dreq)
+{
+ if (wait_for_completion_timeout(&dreq->completion,
+ nfs_cache_getent_timeout * HZ) == 0)
+ return -ETIMEDOUT;
+ return 0;
+}
+
+int nfs_cache_register_sb(struct super_block *sb, struct cache_detail *cd)
+{
+ int ret;
+ struct dentry *dir;
+
+ dir = rpc_d_lookup_sb(sb, "cache");
+ ret = sunrpc_cache_register_pipefs(dir, cd->name, 0600, cd);
+ dput(dir);
+ return ret;
+}
+
+int nfs_cache_register_net(struct net *net, struct cache_detail *cd)
+{
+ struct super_block *pipefs_sb;
+ int ret = 0;
+
+ sunrpc_init_cache_detail(cd);
+ pipefs_sb = rpc_get_sb_net(net);
+ if (pipefs_sb) {
+ ret = nfs_cache_register_sb(pipefs_sb, cd);
+ rpc_put_sb_net(net);
+ if (ret)
+ sunrpc_destroy_cache_detail(cd);
+ }
+ return ret;
+}
+
+void nfs_cache_unregister_sb(struct super_block *sb, struct cache_detail *cd)
+{
+ sunrpc_cache_unregister_pipefs(cd);
+}
+
+void nfs_cache_unregister_net(struct net *net, struct cache_detail *cd)
+{
+ struct super_block *pipefs_sb;
+
+ pipefs_sb = rpc_get_sb_net(net);
+ if (pipefs_sb) {
+ nfs_cache_unregister_sb(pipefs_sb, cd);
+ rpc_put_sb_net(net);
+ }
+ sunrpc_destroy_cache_detail(cd);
+}