diff options
| -rw-r--r-- | security/integrity/ima/ima_crypto.c | 54 |
1 files changed, 34 insertions, 20 deletions
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 7e7e7e7c250a..d9e7728027c6 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -210,7 +210,7 @@ static int ima_calc_file_hash_atfm(struct file *file, { loff_t i_size, offset; char *rbuf[2] = { NULL, }; - int rc, read = 0, rbuf_len, active = 0, ahash_rc = 0; + int rc, rbuf_len, active = 0, ahash_rc = 0; struct ahash_request *req; struct scatterlist sg[1]; struct crypto_wait wait; @@ -257,11 +257,6 @@ static int ima_calc_file_hash_atfm(struct file *file, &rbuf_size[1], 0); } - if (!(file->f_mode & FMODE_READ)) { - file->f_mode |= FMODE_READ; - read = 1; - } - for (offset = 0; offset < i_size; offset += rbuf_len) { if (!rbuf[1] && offset) { /* Not using two buffers, and it is not the first @@ -300,8 +295,6 @@ static int ima_calc_file_hash_atfm(struct file *file, /* wait for the last update request to complete */ rc = ahash_wait(ahash_rc, &wait); out3: - if (read) - file->f_mode &= ~FMODE_READ; ima_free_pages(rbuf[0], rbuf_size[0]); ima_free_pages(rbuf[1], rbuf_size[1]); out2: @@ -336,7 +329,7 @@ static int ima_calc_file_hash_tfm(struct file *file, { loff_t i_size, offset = 0; char *rbuf; - int rc, read = 0; + int rc; SHASH_DESC_ON_STACK(shash, tfm); shash->tfm = tfm; @@ -357,11 +350,6 @@ static int ima_calc_file_hash_tfm(struct file *file, if (!rbuf) return -ENOMEM; - if (!(file->f_mode & FMODE_READ)) { - file->f_mode |= FMODE_READ; - read = 1; - } - while (offset < i_size) { int rbuf_len; @@ -378,8 +366,6 @@ static int ima_calc_file_hash_tfm(struct file *file, if (rc) break; } - if (read) - file->f_mode &= ~FMODE_READ; kfree(rbuf); out: if (!rc) @@ -420,6 +406,8 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) { loff_t i_size; int rc; + struct file *f = file; + bool new_file_instance = false, modified_flags = false; /* * For consistency, fail file's opened with the O_DIRECT flag on @@ -431,15 +419,41 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) return -EINVAL; } - i_size = i_size_read(file_inode(file)); + /* Open a new file instance in O_RDONLY if we cannot read */ + if (!(file->f_mode & FMODE_READ)) { + int flags = file->f_flags & ~(O_WRONLY | O_APPEND | + O_TRUNC | O_CREAT | O_NOCTTY | O_EXCL); + flags |= O_RDONLY; + f = dentry_open(&file->f_path, flags, file->f_cred); + if (IS_ERR(f)) { + /* + * Cannot open the file again, lets modify f_flags + * of original and continue + */ + pr_info_ratelimited("Unable to reopen file for reading.\n"); + f = file; + f->f_flags |= FMODE_READ; + modified_flags = true; + } else { + new_file_instance = true; + } + } + + i_size = i_size_read(file_inode(f)); if (ima_ahash_minsize && i_size >= ima_ahash_minsize) { - rc = ima_calc_file_ahash(file, hash); + rc = ima_calc_file_ahash(f, hash); if (!rc) - return 0; + goto out; } - return ima_calc_file_shash(file, hash); + rc = ima_calc_file_shash(f, hash); +out: + if (new_file_instance) + fput(f); + else if (modified_flags) + f->f_flags &= ~FMODE_READ; + return rc; } /* |