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#include <errno.h>
#include <unistd.h>
#include <signal.h>
#include <stdbool.h>

#include "ioexact.h"

extern volatile sig_atomic_t sigint;

ssize_t read_exact(int fd, void *buf, size_t len, bool mayexit)
{
	ssize_t num = 0, written;

	while (len > 0 && !sigint) {
		if ((written = read(fd, buf, len)) < 0) {
			if (errno == EAGAIN && num > 0)
				continue;
			if (mayexit)
				return -1;
			else
				continue;
		}
		if (!written)
			return 0;

		len -= written;
		buf += written;
		num += written;
	}

	return num;
}

ssize_t write_exact(int fd, void *buf, size_t len, bool mayexit)
{
	ssize_t num = 0, written;

	while (len > 0 && !sigint) {
		if ((written = write(fd, buf, len)) < 0) {
			if (errno == EAGAIN && num > 0)
				continue;
			if (mayexit)
				return -1;
			else
				continue;
		}
		if (!written)
			return 0;

		len -= written;
		buf += written;
		num += written;
	}

	return num;
}
0a6d69d1d6feb4a'>include/uapi/video/Kbuild parent7ce7d89f48834cefece7804d38fc5d85382edf77 (diff)
cgroup: don't online subsystems before cgroup_name/path() are operational
While refactoring cgroup creation, a5bca2152036 ("cgroup: factor out cgroup_create() out of cgroup_mkdir()") incorrectly onlined subsystems before the new cgroup is associated with it kernfs_node. This is fine for cgroup proper but cgroup_name/path() depend on the associated kernfs_node and if a subsystem makes the new cgroup_subsys_state visible, which they're allowed to after onlining, it can lead to NULL dereference. The current code performs cgroup creation and subsystem onlining in cgroup_create() and cgroup_mkdir() makes the cgroup and subsystems visible afterwards. There's no reason to online the subsystems early and we can simply drop cgroup_apply_control_enable() call from cgroup_create() so that the subsystems are onlined and made visible at the same time. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Fixes: a5bca2152036 ("cgroup: factor out cgroup_create() out of cgroup_mkdir()") Cc: stable@vger.kernel.org # v4.6+
Diffstat (limited to 'include/uapi/video/Kbuild')