Re: [PATCH 6/6] Integrity: IMA file free imbalance

From: Serge E. Hallyn
Date: Mon Feb 02 2009 - 18:43:49 EST


Quoting Mimi Zohar (zohar@xxxxxxxxxxxxxxxxxx):
> The number of calls to ima_path_check()/ima_file_free()
> should be balanced. An extra call to fput(), indicates
> the file could have been accessed without first being
> measured.
>
> Although f_count is incremented/decremented in places other
> than fget/fput, like fget_light/fput_light and get_file, the
> current task must already hold a file refcnt. The call to
> __fput() is delayed until the refcnt becomes 0, resulting
> in ima_file_free() flagging any changes.
>
> - add hook to increment opencount for IPC shared memory(SYSV)
> and shmat files
>
> Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxx>

...

> diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c

...

> +static void opencount_get(struct file *file)
> +{
> + struct inode *inode = file->f_dentry->d_inode;
> + struct ima_iint_cache *iint;
> +
> + if (!ima_initialized || !S_ISREG(inode->i_mode))
> + return;
> + iint = ima_iint_find_insert_get(inode);
> + mutex_lock(&iint->mutex);
> + if (iint)

Hey, I think you've got those two lines above mixed
up a bit :)

Very neat, though.

Acked-by: Serge Hallyn <serue@xxxxxxxxxx>

once that's fixed up.

thanks,
-serge
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