From b9fc745db833bbf74b4988493b8cd902a84c9415 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Tue, 19 May 2009 13:25:57 -0400 Subject: integrity: path_check update - Add support in ima_path_check() for integrity checking without incrementing the counts. (Required for nfsd.) - rename and export opencount_get to ima_counts_get - replace ima_shm_check calls with ima_counts_get - export ima_path_check Signed-off-by: Mimi Zohar Signed-off-by: James Morris --- fs/exec.c | 5 ++-- fs/namei.c | 6 +++-- include/linux/ima.h | 11 +++++---- ipc/shm.c | 4 ++-- mm/shmem.c | 2 +- security/integrity/ima/ima_main.c | 48 +++++++++++++++++++++++---------------- 6 files changed, 46 insertions(+), 30 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 998e856c307..618d6d1e2c5 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -130,7 +130,8 @@ SYSCALL_DEFINE1(uselib, const char __user *, library) MAY_READ | MAY_EXEC | MAY_OPEN); if (error) goto exit; - error = ima_path_check(&nd.path, MAY_READ | MAY_EXEC | MAY_OPEN); + error = ima_path_check(&nd.path, MAY_READ | MAY_EXEC | MAY_OPEN, + IMA_COUNT_UPDATE); if (error) goto exit; @@ -680,7 +681,7 @@ struct file *open_exec(const char *name) err = inode_permission(nd.path.dentry->d_inode, MAY_EXEC | MAY_OPEN); if (err) goto out_path_put; - err = ima_path_check(&nd.path, MAY_EXEC | MAY_OPEN); + err = ima_path_check(&nd.path, MAY_EXEC | MAY_OPEN, IMA_COUNT_UPDATE); if (err) goto out_path_put; diff --git a/fs/namei.c b/fs/namei.c index 78f253cd2d4..b05a2b1dea6 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -853,7 +853,8 @@ static int __link_path_walk(const char *name, struct nameidata *nd) err = inode_permission(nd->path.dentry->d_inode, MAY_EXEC); if (!err) - err = ima_path_check(&nd->path, MAY_EXEC); + err = ima_path_check(&nd->path, MAY_EXEC, + IMA_COUNT_UPDATE); if (err) break; @@ -1515,7 +1516,8 @@ int may_open(struct path *path, int acc_mode, int flag) return error; error = ima_path_check(path, - acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC)); + acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC), + IMA_COUNT_UPDATE); if (error) return error; /* diff --git a/include/linux/ima.h b/include/linux/ima.h index 0e2aa45cb0c..b1b827d091a 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -13,14 +13,17 @@ #include struct linux_binprm; +#define IMA_COUNT_UPDATE 1 +#define IMA_COUNT_LEAVE 0 + #ifdef CONFIG_IMA extern int ima_bprm_check(struct linux_binprm *bprm); extern int ima_inode_alloc(struct inode *inode); extern void ima_inode_free(struct inode *inode); -extern int ima_path_check(struct path *path, int mask); +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_shm_check(struct file *file); +extern void ima_counts_get(struct file *file); #else static inline int ima_bprm_check(struct linux_binprm *bprm) @@ -38,7 +41,7 @@ static inline void ima_inode_free(struct inode *inode) return; } -static inline int ima_path_check(struct path *path, int mask) +static inline int ima_path_check(struct path *path, int mask, int update_counts) { return 0; } @@ -53,7 +56,7 @@ static inline int ima_file_mmap(struct file *file, unsigned long prot) return 0; } -static inline void ima_shm_check(struct file *file) +static inline void ima_counts_get(struct file *file) { return; } diff --git a/ipc/shm.c b/ipc/shm.c index faa46da99eb..47b464229cd 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -384,7 +384,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params) error = PTR_ERR(file); if (IS_ERR(file)) goto no_file; - ima_shm_check(file); + ima_counts_get(file); id = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni); if (id < 0) { @@ -891,7 +891,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr) file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations); if (!file) goto out_free; - ima_shm_check(file); + ima_counts_get(file); file->private_data = sfd; file->f_mapping = shp->shm_file->f_mapping; diff --git a/mm/shmem.c b/mm/shmem.c index b25f95ce3db..a817f75f144 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2684,7 +2684,7 @@ int shmem_zero_setup(struct vm_area_struct *vma) if (IS_ERR(file)) return PTR_ERR(file); - ima_shm_check(file); + ima_counts_get(file); if (vma->vm_file) fput(vma->vm_file); vma->vm_file = file; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index c4228c0eb2d..a2eb23310ea 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -125,6 +125,15 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, return rc; } +static void ima_update_counts(struct ima_iint_cache *iint, int mask) +{ + iint->opencount++; + if ((mask & MAY_WRITE) || (mask == 0)) + iint->writecount++; + else if (mask & (MAY_READ | MAY_EXEC)) + iint->readcount++; +} + /** * ima_path_check - based on policy, collect/store measurement. * @path: contains a pointer to the path to be measured @@ -143,7 +152,7 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, * Return 0 on success, an error code on failure. * (Based on the results of appraise_measurement().) */ -int ima_path_check(struct path *path, int mask) +int ima_path_check(struct path *path, int mask, int update_counts) { struct inode *inode = path->dentry->d_inode; struct ima_iint_cache *iint; @@ -157,11 +166,8 @@ int ima_path_check(struct path *path, int mask) return 0; mutex_lock(&iint->mutex); - iint->opencount++; - if ((mask & MAY_WRITE) || (mask == 0)) - iint->writecount++; - else if (mask & (MAY_READ | MAY_EXEC)) - iint->readcount++; + if (update_counts) + ima_update_counts(iint, mask); rc = ima_must_measure(iint, inode, MAY_READ, PATH_CHECK); if (rc < 0) @@ -197,6 +203,7 @@ out: kref_put(&iint->refcount, iint_free); return 0; } +EXPORT_SYMBOL_GPL(ima_path_check); static int process_measurement(struct file *file, const unsigned char *filename, int mask, int function) @@ -225,7 +232,16 @@ out: return rc; } -static void opencount_get(struct file *file) +/* + * ima_opens_get - increment file counts + * + * - for IPC shm and shmat file. + * - for nfsd exported files. + * + * Increment the counts for these files to prevent unnecessary + * imbalance messages. + */ +void ima_counts_get(struct file *file) { struct inode *inode = file->f_dentry->d_inode; struct ima_iint_cache *iint; @@ -237,8 +253,14 @@ static void opencount_get(struct file *file) return; mutex_lock(&iint->mutex); iint->opencount++; + if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) + iint->readcount++; + + if (file->f_mode & FMODE_WRITE) + iint->writecount++; mutex_unlock(&iint->mutex); } +EXPORT_SYMBOL_GPL(ima_counts_get); /** * ima_file_mmap - based on policy, collect/store measurement. @@ -263,18 +285,6 @@ int ima_file_mmap(struct file *file, unsigned long prot) return 0; } -/* - * ima_shm_check - IPC shm and shmat create/fput a file - * - * Maintain the opencount for these files to prevent unnecessary - * imbalance messages. - */ -void ima_shm_check(struct file *file) -{ - opencount_get(file); - return; -} - /** * ima_bprm_check - based on policy, collect/store measurement. * @bprm: contains the linux_binprm structure -- cgit v1.2.3-70-g09d2