[PATCH v3 08/14] sysctl: Add size to register_net_sysctl function
From: Joel Granados <hidden>
Date: 2023-08-09 10:50:38
Also in:
bridge, linux-fsdevel, linux-hams, linux-rdma, linux-s390, linux-sctp, lkml, lvs-devel, mptcp, netfilter-devel
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
This commit adds size to the register_net_sysctl indirection function to facilitate the removal of the sentinel elements (last empty markers) from the ctl_table arrays. Though we don't actually remove any sentinels in this commit, register_net_sysctl* now has the capability of forwarding table_size for when that happens. We create a new function register_net_sysctl_sz with an extra size argument. A macro replaces the existing register_net_sysctl. The size in the macro is SIZE_MAX instead of ARRAY_SIZE to avoid compilation errors while we systematically migrate to register_net_sysctl_sz. Will change to ARRAY_SIZE in subsequent commits. Care is taken to add table_size to the stopping criteria in such a way that when we remove the empty sentinel element, it will continue stopping in the last element of the ctl_table array. Signed-off-by: Joel Granados <redacted> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- include/net/net_namespace.h | 10 ++++++---- net/sysctl_net.c | 22 +++++++++++++--------- 2 files changed, 19 insertions(+), 13 deletions(-)
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 78beaa765c73..e4e5fe75a281 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h@@ -469,15 +469,17 @@ void unregister_pernet_device(struct pernet_operations *); struct ctl_table; +#define register_net_sysctl(net, path, table) \ + register_net_sysctl_sz(net, path, table, SIZE_MAX) #ifdef CONFIG_SYSCTL int net_sysctl_init(void); -struct ctl_table_header *register_net_sysctl(struct net *net, const char *path, - struct ctl_table *table); +struct ctl_table_header *register_net_sysctl_sz(struct net *net, const char *path, + struct ctl_table *table, size_t table_size); void unregister_net_sysctl_table(struct ctl_table_header *header); #else static inline int net_sysctl_init(void) { return 0; } -static inline struct ctl_table_header *register_net_sysctl(struct net *net, - const char *path, struct ctl_table *table) +static inline struct ctl_table_header *register_net_sysctl_sz(struct net *net, + const char *path, struct ctl_table *table, size_t table_size) { return NULL; }
diff --git a/net/sysctl_net.c b/net/sysctl_net.c
index d9cbbb51b143..051ed5f6fc93 100644
--- a/net/sysctl_net.c
+++ b/net/sysctl_net.c@@ -122,12 +122,13 @@ __init int net_sysctl_init(void) * allocated. */ static void ensure_safe_net_sysctl(struct net *net, const char *path, - struct ctl_table *table) + struct ctl_table *table, size_t table_size) { struct ctl_table *ent; pr_debug("Registering net sysctl (net %p): %s\n", net, path); - for (ent = table; ent->procname; ent++) { + ent = table; + for (size_t i = 0; i < table_size && ent->procname; ent++, i++) { unsigned long addr; const char *where;
@@ -160,21 +161,24 @@ static void ensure_safe_net_sysctl(struct net *net, const char *path, } } -struct ctl_table_header *register_net_sysctl(struct net *net, - const char *path, struct ctl_table *table) +struct ctl_table_header *register_net_sysctl_sz(struct net *net, + const char *path, + struct ctl_table *table, + size_t table_size) { - int count = 0; + int count; struct ctl_table *entry; if (!net_eq(net, &init_net)) - ensure_safe_net_sysctl(net, path, table); + ensure_safe_net_sysctl(net, path, table, table_size); - for (entry = table; entry->procname; entry++) - count++; + entry = table; + for (count = 0 ; count < table_size && entry->procname; entry++, count++) + ; return __register_sysctl_table(&net->sysctls, path, table, count); } -EXPORT_SYMBOL_GPL(register_net_sysctl); +EXPORT_SYMBOL_GPL(register_net_sysctl_sz); void unregister_net_sysctl_table(struct ctl_table_header *header) {
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2.30.2