From 9dad5feb49a5c3b99838b102555cdbedf244320a Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Wed, 16 Sep 2020 21:11:32 -0700 Subject: fscrypt: stop pretending that key setup is nofs-safe fscrypt_get_encryption_info() has never actually been safe to call in a context that needs GFP_NOFS, since it calls crypto_alloc_skcipher(). crypto_alloc_skcipher() isn't GFP_NOFS-safe, even if called under memalloc_nofs_save(). This is because it may load kernel modules, and also because it internally takes crypto_alg_sem. Other tasks can do GFP_KERNEL allocations while holding crypto_alg_sem for write. The use of fscrypt_init_mutex isn't GFP_NOFS-safe either. So, stop pretending that fscrypt_get_encryption_info() is nofs-safe. I.e., when it allocates memory, just use GFP_KERNEL instead of GFP_NOFS. Note, another reason to do this is that GFP_NOFS is deprecated in favor of using memalloc_nofs_save() in the proper places. Acked-by: Jeff Layton Link: https://lore.kernel.org/r/20200917041136.178600-10-ebiggers@kernel.org Signed-off-by: Eric Biggers --- fs/crypto/keysetup_v1.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'fs/crypto/keysetup_v1.c') diff --git a/fs/crypto/keysetup_v1.c b/fs/crypto/keysetup_v1.c index a3cb52572b05..2762c5350432 100644 --- a/fs/crypto/keysetup_v1.c +++ b/fs/crypto/keysetup_v1.c @@ -60,7 +60,7 @@ static int derive_key_aes(const u8 *master_key, goto out; } crypto_skcipher_set_flags(tfm, CRYPTO_TFM_REQ_FORBID_WEAK_KEYS); - req = skcipher_request_alloc(tfm, GFP_NOFS); + req = skcipher_request_alloc(tfm, GFP_KERNEL); if (!req) { res = -ENOMEM; goto out; @@ -99,7 +99,7 @@ find_and_lock_process_key(const char *prefix, const struct user_key_payload *ukp; const struct fscrypt_key *payload; - description = kasprintf(GFP_NOFS, "%s%*phN", prefix, + description = kasprintf(GFP_KERNEL, "%s%*phN", prefix, FSCRYPT_KEY_DESCRIPTOR_SIZE, descriptor); if (!description) return ERR_PTR(-ENOMEM); @@ -228,7 +228,7 @@ fscrypt_get_direct_key(const struct fscrypt_info *ci, const u8 *raw_key) return dk; /* Nope, allocate one. */ - dk = kzalloc(sizeof(*dk), GFP_NOFS); + dk = kzalloc(sizeof(*dk), GFP_KERNEL); if (!dk) return ERR_PTR(-ENOMEM); refcount_set(&dk->dk_refcount, 1); @@ -272,7 +272,7 @@ static int setup_v1_file_key_derived(struct fscrypt_info *ci, * This cannot be a stack buffer because it will be passed to the * scatterlist crypto API during derive_key_aes(). */ - derived_key = kmalloc(ci->ci_mode->keysize, GFP_NOFS); + derived_key = kmalloc(ci->ci_mode->keysize, GFP_KERNEL); if (!derived_key) return -ENOMEM; -- cgit