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SubjectRe: [2.6 patch] kernel/cgroup.c: remove dead code
I think I'd rather not make this change - if we later changed the size
of release_agent_path[] this could silently fail. Can we get around
the coverity checker somehow?

Paul

On 10/24/07, Adrian Bunk <bunk@kernel.org> wrote:
> This patch removes dead code spotted by the Coverity checker
> (look at the "(nbytes >= PATH_MAX)" check).
>
> Signed-off-by: Adrian Bunk <bunk@kernel.org>
>
> ---
>
> kernel/cgroup.c | 18 ++++++++----------
> 1 file changed, 8 insertions(+), 10 deletions(-)
>
> --- linux-2.6/kernel/cgroup.c.old 2007-10-23 18:37:43.000000000 +0200
> +++ linux-2.6/kernel/cgroup.c 2007-10-23 18:39:15.000000000 +0200
> @@ -1320,90 +1320,88 @@ static ssize_t cgroup_common_file_write(
>
> if (nbytes >= PATH_MAX)
> return -E2BIG;
>
> /* +1 for nul-terminator */
> buffer = kmalloc(nbytes + 1, GFP_KERNEL);
> if (buffer == NULL)
> return -ENOMEM;
>
> if (copy_from_user(buffer, userbuf, nbytes)) {
> retval = -EFAULT;
> goto out1;
> }
> buffer[nbytes] = 0; /* nul-terminate */
>
> mutex_lock(&cgroup_mutex);
>
> if (cgroup_is_removed(cgrp)) {
> retval = -ENODEV;
> goto out2;
> }
>
> switch (type) {
> case FILE_TASKLIST:
> retval = attach_task_by_pid(cgrp, buffer);
> break;
> case FILE_NOTIFY_ON_RELEASE:
> clear_bit(CGRP_RELEASABLE, &cgrp->flags);
> if (simple_strtoul(buffer, NULL, 10) != 0)
> set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
> else
> clear_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
> break;
> case FILE_RELEASE_AGENT:
> {
> struct cgroupfs_root *root = cgrp->root;
> /* Strip trailing newline */
> if (nbytes && (buffer[nbytes-1] == '\n')) {
> buffer[nbytes-1] = 0;
> }
> - if (nbytes < sizeof(root->release_agent_path)) {
> - /* We never write anything other than '\0'
> - * into the last char of release_agent_path,
> - * so it always remains a NUL-terminated
> - * string */
> - strncpy(root->release_agent_path, buffer, nbytes);
> - root->release_agent_path[nbytes] = 0;
> - } else {
> - retval = -ENOSPC;
> - }
> +
> + /* We never write anything other than '\0'
> + * into the last char of release_agent_path,
> + * so it always remains a NUL-terminated
> + * string */
> + strncpy(root->release_agent_path, buffer, nbytes);
> + root->release_agent_path[nbytes] = 0;
> +
> break;
> }
> default:
> retval = -EINVAL;
> goto out2;
> }
>
> if (retval == 0)
> retval = nbytes;
> out2:
> mutex_unlock(&cgroup_mutex);
> out1:
> kfree(buffer);
> return retval;
> }
>
> static ssize_t cgroup_file_write(struct file *file, const char __user *buf,
> size_t nbytes, loff_t *ppos)
> {
> struct cftype *cft = __d_cft(file->f_dentry);
> struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
>
> if (!cft)
> return -ENODEV;
> if (cft->write)
> return cft->write(cgrp, cft, file, buf, nbytes, ppos);
> if (cft->write_uint)
> return cgroup_write_uint(cgrp, cft, file, buf, nbytes, ppos);
> return -EINVAL;
> }
>
> static ssize_t cgroup_read_uint(struct cgroup *cgrp, struct cftype *cft,
> struct file *file,
> char __user *buf, size_t nbytes,
> loff_t *ppos)
> {
> char tmp[64];
> u64 val = cft->read_uint(cgrp, cft);
> int len = sprintf(tmp, "%llu\n", (unsigned long long) val);
>
>
>
-
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