From 497f32337073a2da102c49a53779097b5394711b Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Mon, 25 Oct 2010 14:41:32 -0400 Subject: IMA: use unsigned int instead of long for counters Currently IMA uses 2 longs in struct inode. To save space (and as it seems impossible to overflow 32 bits) we switch these to unsigned int. The switch to unsigned does require slightly different checks for underflow, but it isn't complex. Signed-off-by: Eric Paris Acked-by: Mimi Zohar Signed-off-by: Linus Torvalds --- security/integrity/ima/ima.h | 4 ++-- security/integrity/ima/ima_iint.c | 4 ++-- security/integrity/ima/ima_main.c | 15 ++++++++++----- 3 files changed, 14 insertions(+), 9 deletions(-) (limited to 'security/integrity') diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index 3d701084eac..000d13ab1a2 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -106,8 +106,8 @@ struct ima_iint_cache { unsigned long flags; u8 digest[IMA_DIGEST_SIZE]; struct mutex mutex; /* protects: version, flags, digest */ - long readcount; /* measured files readcount */ - long writecount; /* measured files writecount */ + unsigned int readcount; /* measured files readcount */ + unsigned int writecount;/* measured files writecount */ struct kref refcount; /* ima_iint_cache reference count */ }; diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c index 8e64313ed18..db71a13f27f 100644 --- a/security/integrity/ima/ima_iint.c +++ b/security/integrity/ima/ima_iint.c @@ -125,12 +125,12 @@ void iint_free(struct kref *kref) iint->version = 0; iint->flags = 0UL; if (iint->readcount != 0) { - printk(KERN_INFO "%s: readcount: %ld\n", __func__, + printk(KERN_INFO "%s: readcount: %u\n", __func__, iint->readcount); iint->readcount = 0; } if (iint->writecount != 0) { - printk(KERN_INFO "%s: writecount: %ld\n", __func__, + printk(KERN_INFO "%s: writecount: %u\n", __func__, iint->writecount); iint->writecount = 0; } diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 995bd1b98fa..5a1bf3df11f 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -178,11 +178,18 @@ static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode, struct file *file) { mode_t mode = file->f_mode; + bool dump = false; + BUG_ON(!mutex_is_locked(&iint->mutex)); - if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) + if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) { + if (unlikely(iint->readcount == 0)) + dump = true; iint->readcount--; + } if (mode & FMODE_WRITE) { + if (unlikely(iint->writecount == 0)) + dump = true; iint->writecount--; if (iint->writecount == 0) { if (iint->version != inode->i_version) @@ -190,10 +197,8 @@ static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode, } } - if (((iint->readcount < 0) || - (iint->writecount < 0)) && - !ima_limit_imbalance(file)) { - printk(KERN_INFO "%s: open/free imbalance (r:%ld w:%ld)\n", + if (dump && !ima_limit_imbalance(file)) { + printk(KERN_INFO "%s: open/free imbalance (r:%u w:%u)\n", __func__, iint->readcount, iint->writecount); dump_stack(); } -- cgit v1.2.3