linux/fs/verity/init.c
Eric Biggers 456ae5fe9b fsverity: move sysctl registration out of signature.c
Currently the registration of the fsverity sysctls happens in
signature.c, which couples it to CONFIG_FS_VERITY_BUILTIN_SIGNATURES.

This makes it hard to add new sysctls unrelated to builtin signatures.

Also, some users have started checking whether the directory
/proc/sys/fs/verity exists as a way to tell whether fsverity is
supported.  This isn't the intended method; instead, the existence of
/sys/fs/$fstype/features/verity should be checked, or users should just
try to use the fsverity ioctls.  Regardless, it should be made to work
as expected without a dependency on CONFIG_FS_VERITY_BUILTIN_SIGNATURES.

Therefore, move the sysctl registration into init.c.  With
CONFIG_FS_VERITY_BUILTIN_SIGNATURES, nothing changes.  Without it, but
with CONFIG_FS_VERITY, an empty list of sysctls is now registered.

Link: https://lore.kernel.org/r/20230705212743.42180-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2023-07-11 22:57:03 -07:00

75 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* fs-verity module initialization and logging
*
* Copyright 2019 Google LLC
*/
#include "fsverity_private.h"
#include <linux/ratelimit.h>
#ifdef CONFIG_SYSCTL
static struct ctl_table_header *fsverity_sysctl_header;
static struct ctl_table fsverity_sysctl_table[] = {
#ifdef CONFIG_FS_VERITY_BUILTIN_SIGNATURES
{
.procname = "require_signatures",
.data = &fsverity_require_signatures,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE,
},
#endif
{ }
};
static void __init fsverity_init_sysctl(void)
{
fsverity_sysctl_header = register_sysctl("fs/verity",
fsverity_sysctl_table);
if (!fsverity_sysctl_header)
panic("fsverity sysctl registration failed");
}
#else /* CONFIG_SYSCTL */
static inline void fsverity_init_sysctl(void)
{
}
#endif /* !CONFIG_SYSCTL */
void fsverity_msg(const struct inode *inode, const char *level,
const char *fmt, ...)
{
static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
struct va_format vaf;
va_list args;
if (!__ratelimit(&rs))
return;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
if (inode)
printk("%sfs-verity (%s, inode %lu): %pV\n",
level, inode->i_sb->s_id, inode->i_ino, &vaf);
else
printk("%sfs-verity: %pV\n", level, &vaf);
va_end(args);
}
static int __init fsverity_init(void)
{
fsverity_check_hash_algs();
fsverity_init_info_cache();
fsverity_init_workqueue();
fsverity_init_sysctl();
fsverity_init_signature();
return 0;
}
late_initcall(fsverity_init)