From e0d5bd2aec4e69e720ee86958503923cafb45be5 Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Fri, 4 Dec 2009 15:48:00 -0500 Subject: [PATCH] IMA: clean up the IMA counts updating code We currently have a lot of duplicated code around ima file counts. Clean that all up. Signed-off-by: Eric Paris Acked-by: Serge Hallyn Signed-off-by: Al Viro --- security/integrity/ima/ima.h | 1 - security/integrity/ima/ima_main.c | 118 ++++++++++++++++++------------ 2 files changed, 70 insertions(+), 49 deletions(-) diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index 349aabc83297..268ef57b9142 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -97,7 +97,6 @@ static inline unsigned long ima_hash_key(u8 *digest) /* iint cache flags */ #define IMA_MEASURED 1 -#define IMA_IINT_DUMP_STACK 512 /* integrity data associated with an inode */ struct ima_iint_cache { diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 96fafc01e2c7..e041233b4d2a 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -13,8 +13,8 @@ * License. * * File: ima_main.c - * implements the IMA hooks: ima_bprm_check, ima_file_mmap, - * and ima_path_check. + * implements the IMA hooks: ima_bprm_check, ima_file_mmap, + * and ima_path_check. */ #include #include @@ -35,6 +35,69 @@ static int __init hash_setup(char *str) } __setup("ima_hash=", hash_setup); +/* + * Update the counts given an fmode_t + */ +static void ima_inc_counts(struct ima_iint_cache *iint, fmode_t mode) +{ + BUG_ON(!mutex_is_locked(&iint->mutex)); + + iint->opencount++; + if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) + iint->readcount++; + if (mode & FMODE_WRITE) + iint->writecount++; +} + +/* + * Update the counts given open flags instead of fmode + */ +static void ima_inc_counts_flags(struct ima_iint_cache *iint, int flags) +{ + ima_inc_counts(iint, (__force fmode_t)((flags+1) & O_ACCMODE)); +} + +/* + * Decrement ima counts + */ +static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode, + fmode_t mode) +{ + BUG_ON(!mutex_is_locked(&iint->mutex)); + + iint->opencount--; + if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) + iint->readcount--; + if (mode & FMODE_WRITE) { + iint->writecount--; + if (iint->writecount == 0) { + if (iint->version != inode->i_version) + iint->flags &= ~IMA_MEASURED; + } + } + + if ((iint->opencount < 0) || + (iint->readcount < 0) || + (iint->writecount < 0)) { + static int dumped; + + if (dumped) + return; + dumped = 1; + + printk(KERN_INFO "%s: open/free imbalance (r:%ld w:%ld o:%ld)\n", + __FUNCTION__, iint->readcount, iint->writecount, + iint->opencount); + dump_stack(); + } +} + +static void ima_dec_counts_flags(struct ima_iint_cache *iint, + struct inode *inode, int flags) +{ + ima_dec_counts(iint, inode, (__force fmode_t)((flags+1) & O_ACCMODE)); +} + /** * ima_file_free - called on __fput() * @file: pointer to file structure being freed @@ -54,29 +117,7 @@ void ima_file_free(struct file *file) return; mutex_lock(&iint->mutex); - if (iint->opencount <= 0) { - printk(KERN_INFO - "%s: %s open/free imbalance (r:%ld w:%ld o:%ld f:%ld)\n", - __FUNCTION__, file->f_dentry->d_name.name, - iint->readcount, iint->writecount, - iint->opencount, atomic_long_read(&file->f_count)); - if (!(iint->flags & IMA_IINT_DUMP_STACK)) { - dump_stack(); - iint->flags |= IMA_IINT_DUMP_STACK; - } - } - iint->opencount--; - - if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) - iint->readcount--; - - if (file->f_mode & FMODE_WRITE) { - iint->writecount--; - if (iint->writecount == 0) { - if (iint->version != inode->i_version) - iint->flags &= ~IMA_MEASURED; - } - } + ima_dec_counts(iint, inode, file->f_mode); mutex_unlock(&iint->mutex); kref_put(&iint->refcount, iint_free); } @@ -116,8 +157,7 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, { int rc = 0; - iint->opencount++; - iint->readcount++; + ima_inc_counts(iint, file->f_mode); rc = ima_collect_measurement(iint, file); if (!rc) @@ -125,15 +165,6 @@ 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 @@ -167,7 +198,7 @@ int ima_path_check(struct path *path, int mask, int update_counts) mutex_lock(&iint->mutex); if (update_counts) - ima_update_counts(iint, mask); + ima_inc_counts_flags(iint, mask); rc = ima_must_measure(iint, inode, MAY_READ, PATH_CHECK); if (rc < 0) @@ -260,11 +291,7 @@ void ima_counts_put(struct path *path, int mask) return; mutex_lock(&iint->mutex); - iint->opencount--; - if ((mask & MAY_WRITE) || (mask == 0)) - iint->writecount--; - else if (mask & (MAY_READ | MAY_EXEC)) - iint->readcount--; + ima_dec_counts_flags(iint, inode, mask); mutex_unlock(&iint->mutex); kref_put(&iint->refcount, iint_free); @@ -290,12 +317,7 @@ void ima_counts_get(struct file *file) if (!iint) 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++; + ima_inc_counts(iint, file->f_mode); mutex_unlock(&iint->mutex); kref_put(&iint->refcount, iint_free);