From 63f668f0def1b58ed1e480661c4043d2b11abc6c Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Wed, 24 Jul 2019 11:07:59 -0700 Subject: [PATCH] fscrypt: improve warning messages for unsupported encryption contexts When fs/crypto/ encounters an inode with an invalid encryption context, currently it prints a warning if the pair of encryption modes are unrecognized, but it's silent if there are other problems such as unsupported context size, format, or flags. To help people debug such situations, add more warning messages. Signed-off-by: Eric Biggers --- fs/crypto/keyinfo.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c index d0eb901a6d1a..e5ab18d98f32 100644 --- a/fs/crypto/keyinfo.c +++ b/fs/crypto/keyinfo.c @@ -510,8 +510,12 @@ int fscrypt_get_encryption_info(struct inode *inode) res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx)); if (res < 0) { if (!fscrypt_dummy_context_enabled(inode) || - IS_ENCRYPTED(inode)) + IS_ENCRYPTED(inode)) { + fscrypt_warn(inode, + "Error %d getting encryption context", + res); return res; + } /* Fake up a context for an unencrypted directory */ memset(&ctx, 0, sizeof(ctx)); ctx.format = FS_ENCRYPTION_CONTEXT_FORMAT_V1; @@ -519,14 +523,22 @@ int fscrypt_get_encryption_info(struct inode *inode) ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS; memset(ctx.master_key_descriptor, 0x42, FS_KEY_DESCRIPTOR_SIZE); } else if (res != sizeof(ctx)) { + fscrypt_warn(inode, + "Unknown encryption context size (%d bytes)", res); return -EINVAL; } - if (ctx.format != FS_ENCRYPTION_CONTEXT_FORMAT_V1) + if (ctx.format != FS_ENCRYPTION_CONTEXT_FORMAT_V1) { + fscrypt_warn(inode, "Unknown encryption context version (%d)", + ctx.format); return -EINVAL; + } - if (ctx.flags & ~FS_POLICY_FLAGS_VALID) + if (ctx.flags & ~FS_POLICY_FLAGS_VALID) { + fscrypt_warn(inode, "Unknown encryption context flags (0x%02x)", + ctx.flags); return -EINVAL; + } crypt_info = kmem_cache_zalloc(fscrypt_info_cachep, GFP_NOFS); if (!crypt_info)