fscrypt: use a common logging function

Use a common function for fscrypt warning and error messages so that all
the messages are consistently ratelimited, include the "fscrypt:"
prefix, and include the filesystem name if applicable.

Also fix up a few of the log messages to be more descriptive.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

5 files changed, 57 insertions, 21 deletions

diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index f46191b6b3ed..243a269e6c5f 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -174,9 +174,10 @@ int fscrypt_do_page_crypto(const struct inode *inode, fscrypt_direction_t rw,
                 res = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
         skcipher_request_free(req);
         if (res) {
-                printk_ratelimited(KERN_ERR
-                        "%s: crypto_skcipher_encrypt() returned %d\n",
-                        __func__, res);
+                fscrypt_err(inode->i_sb,
+                            "%scryption failed for inode %lu, block %llu: %d",
+                            (rw == FS_DECRYPT ? "de" : "en"),
+                            inode->i_ino, lblk_num, res);
                 return res;
         }
         return 0;
@@ -416,6 +417,27 @@ fail:
         return res;
 }
 
+void fscrypt_msg(struct super_block *sb, 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 (sb)
+                printk("%sfscrypt (%s): %pV\n", level, sb->s_id, &vaf);
+        else
+                printk("%sfscrypt: %pV\n", level, &vaf);
+        va_end(args);
+}
+
 /**
  * fscrypt_init() - Set up for fs encryption.
  */
diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 39091fc31e98..d7a0f682ca12 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -71,8 +71,9 @@ int fname_encrypt(struct inode *inode, const struct qstr *iname,
         res = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
         skcipher_request_free(req);
         if (res < 0) {
-                printk_ratelimited(KERN_ERR
-                                "%s: Error (error code %d)\n", __func__, res);
+                fscrypt_err(inode->i_sb,
+                            "Filename encryption failed for inode %lu: %d",
+                            inode->i_ino, res);
                 return res;
         }
 
@@ -115,8 +116,9 @@ static int fname_decrypt(struct inode *inode,
         res = crypto_wait_req(crypto_skcipher_decrypt(req), &wait);
         skcipher_request_free(req);
         if (res < 0) {
-                printk_ratelimited(KERN_ERR
-                                "%s: Error (error code %d)\n", __func__, res);
+                fscrypt_err(inode->i_sb,
+                            "Filename decryption failed for inode %lu: %d",
+                            inode->i_ino, res);
                 return res;
         }
 
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 8358610d6558..09d6c72635b6 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -100,6 +100,14 @@ extern struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx,
                                               gfp_t gfp_flags);
 extern const struct dentry_operations fscrypt_d_ops;
 
+extern void __printf(3, 4) __cold
+fscrypt_msg(struct super_block *sb, const char *level, const char *fmt, ...);
+
+#define fscrypt_warn(sb, fmt, ...)              \
+        fscrypt_msg(sb, KERN_WARNING, fmt, ##__VA_ARGS__)
+#define fscrypt_err(sb, fmt, ...)               \
+        fscrypt_msg(sb, KERN_ERR, fmt, ##__VA_ARGS__)
+
 /* fname.c */
 extern int fname_encrypt(struct inode *inode, const struct qstr *iname,
                          u8 *out, unsigned int olen);
diff --git a/fs/crypto/hooks.c b/fs/crypto/hooks.c
index bec06490fb13..926e5df20ec3 100644
--- a/fs/crypto/hooks.c
+++ b/fs/crypto/hooks.c
@@ -39,8 +39,9 @@ int fscrypt_file_open(struct inode *inode, struct file *filp)
         dir = dget_parent(file_dentry(filp));
         if (IS_ENCRYPTED(d_inode(dir)) &&
             !fscrypt_has_permitted_context(d_inode(dir), inode)) {
-                pr_warn_ratelimited("fscrypt: inconsistent encryption contexts: %lu/%lu",
-                                    d_inode(dir)->i_ino, inode->i_ino);
+                fscrypt_warn(inode->i_sb,
+                             "inconsistent encryption contexts: %lu/%lu",
+                             d_inode(dir)->i_ino, inode->i_ino);
                 err = -EPERM;
         }
         dput(dir);
diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
index f6d6acd37b97..f63bfd6dffd6 100644
--- a/fs/crypto/keyinfo.c
+++ b/fs/crypto/keyinfo.c
@@ -103,9 +103,8 @@ static int validate_user_key(struct fscrypt_info *crypt_info,
 
         if (master_key->size < min_keysize || master_key->size > FS_MAX_KEY_SIZE
             || master_key->size % AES_BLOCK_SIZE != 0) {
-                printk_once(KERN_WARNING
-                                "%s: key size incorrect: %d\n",
-                                __func__, master_key->size);
+                fscrypt_warn(NULL, "key size incorrect: %u",
+                             master_key->size);
                 res = -ENOKEY;
                 goto out;
         }
@@ -132,9 +131,10 @@ static int determine_cipher_type(struct fscrypt_info *ci, struct inode *inode,
         u32 mode;
 
         if (!fscrypt_valid_enc_modes(ci->ci_data_mode, ci->ci_filename_mode)) {
-                pr_warn_ratelimited("fscrypt: inode %lu uses unsupported encryption modes (contents mode %d, filenames mode %d)\n",
-                                    inode->i_ino,
-                                    ci->ci_data_mode, ci->ci_filename_mode);
+                fscrypt_warn(inode->i_sb,
+                             "inode %lu uses unsupported encryption modes (contents mode %d, filenames mode %d)",
+                             inode->i_ino, ci->ci_data_mode,
+                             ci->ci_filename_mode);
                 return -EINVAL;
         }
 
@@ -173,8 +173,9 @@ static int derive_essiv_salt(const u8 *key, int keysize, u8 *salt)
 
                 tfm = crypto_alloc_shash("sha256", 0, 0);
                 if (IS_ERR(tfm)) {
-                        pr_warn_ratelimited("fscrypt: error allocating SHA-256 transform: %ld\n",
-                                            PTR_ERR(tfm));
+                        fscrypt_warn(NULL,
+                                     "error allocating SHA-256 transform: %ld",
+                                     PTR_ERR(tfm));
                         return PTR_ERR(tfm);
                 }
                 prev_tfm = cmpxchg(&essiv_hash_tfm, NULL, tfm);
@@ -309,8 +310,9 @@ int fscrypt_get_encryption_info(struct inode *inode)
         ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
         if (IS_ERR(ctfm)) {
                 res = PTR_ERR(ctfm);
-                pr_debug("%s: error %d (inode %lu) allocating crypto tfm\n",
-                         __func__, res, inode->i_ino);
+                fscrypt_warn(inode->i_sb,
+                             "error allocating '%s' transform for inode %lu: %d",
+                             cipher_str, inode->i_ino, res);
                 goto out;
         }
         crypt_info->ci_ctfm = ctfm;
@@ -327,8 +329,9 @@ int fscrypt_get_encryption_info(struct inode *inode)
             crypt_info->ci_data_mode == FS_ENCRYPTION_MODE_AES_128_CBC) {
                 res = init_essiv_generator(crypt_info, raw_key, keysize);
                 if (res) {
-                        pr_debug("%s: error %d (inode %lu) allocating essiv tfm\n",
-                                 __func__, res, inode->i_ino);
+                        fscrypt_warn(inode->i_sb,
+                                     "error initializing ESSIV generator for inode %lu: %d",
+                                     inode->i_ino, res);
                         goto out;
                 }
         }