From 94e5d714f604d4cb4cb13163f01ede278e69258b Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Fri, 26 Jun 2009 14:05:27 -0400 Subject: [PATCH] integrity: add ima_counts_put (updated) This patch fixes an imbalance message as reported by J.R. Okajima. The IMA file counters are incremented in ima_path_check. If the actual open fails, such as ETXTBSY, decrement the counters to prevent unnecessary imbalance messages. Reported-by: J.R. Okajima Signed-off-by: Mimi Zohar Signed-off-by: James Morris --- fs/namei.c | 7 +++++++ include/linux/ima.h | 6 ++++++ security/integrity/ima/ima_main.c | 29 ++++++++++++++++++++++++++++- 3 files changed, 41 insertions(+), 1 deletion(-) diff --git a/fs/namei.c b/fs/namei.c index 5b961eb71cbf..f3c5b278895a 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1761,6 +1761,10 @@ struct file *do_filp_open(int dfd, const char *pathname, goto exit; } filp = nameidata_to_filp(&nd, open_flag); + if (IS_ERR(filp)) + ima_counts_put(&nd.path, + acc_mode & (MAY_READ | MAY_WRITE | + MAY_EXEC)); mnt_drop_write(nd.path.mnt); if (nd.root.mnt) path_put(&nd.root); @@ -1817,6 +1821,9 @@ struct file *do_filp_open(int dfd, const char *pathname, goto exit; } filp = nameidata_to_filp(&nd, open_flag); + if (IS_ERR(filp)) + ima_counts_put(&nd.path, + acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC)); /* * It is now safe to drop the mnt write * because the filp has had a write taken diff --git a/include/linux/ima.h b/include/linux/ima.h index b1b827d091a9..0e3f2a4c25f6 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -24,6 +24,7 @@ extern int ima_path_check(struct path *path, int mask, int update_counts); extern void ima_file_free(struct file *file); extern int ima_file_mmap(struct file *file, unsigned long prot); extern void ima_counts_get(struct file *file); +extern void ima_counts_put(struct path *path, int mask); #else static inline int ima_bprm_check(struct linux_binprm *bprm) @@ -60,5 +61,10 @@ static inline void ima_counts_get(struct file *file) { return; } + +static inline void ima_counts_put(struct path *path, int mask) +{ + return; +} #endif /* CONFIG_IMA_H */ #endif /* _LINUX_IMA_H */ diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 6f611874d10e..101c512564ec 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -238,7 +238,34 @@ static int process_measurement(struct file *file, const unsigned char *filename, } /* - * ima_opens_get - increment file counts + * ima_counts_put - decrement file counts + * + * File counts are incremented in ima_path_check. On file open + * error, such as ETXTBSY, decrement the counts to prevent + * unnecessary imbalance messages. + */ +void ima_counts_put(struct path *path, int mask) +{ + struct inode *inode = path->dentry->d_inode; + struct ima_iint_cache *iint; + + if (!ima_initialized || !S_ISREG(inode->i_mode)) + return; + iint = ima_iint_find_insert_get(inode); + if (!iint) + return; + + mutex_lock(&iint->mutex); + iint->opencount--; + if ((mask & MAY_WRITE) || (mask == 0)) + iint->writecount--; + else if (mask & (MAY_READ | MAY_EXEC)) + iint->readcount--; + mutex_unlock(&iint->mutex); +} + +/* + * ima_counts_get - increment file counts * * - for IPC shm and shmat file. * - for nfsd exported files. -- GitLab