diff options
| -rw-r--r-- | block/blk-throttle.c | 4 | ||||
| -rw-r--r-- | block/cfq-iosched.c | 3 | ||||
| -rw-r--r-- | include/linux/cgroup.h | 5 | ||||
| -rw-r--r-- | kernel/cgroup.c | 18 |
4 files changed, 11 insertions, 19 deletions
diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 1474c3ab7e72..861c363e4129 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1425,28 +1425,24 @@ static struct cftype throtl_files[] = { .private = offsetof(struct throtl_grp, bps[READ]), .seq_show = tg_print_conf_u64, .write_string = tg_set_conf_u64, - .max_write_len = 256, }, { .name = "throttle.write_bps_device", .private = offsetof(struct throtl_grp, bps[WRITE]), .seq_show = tg_print_conf_u64, .write_string = tg_set_conf_u64, - .max_write_len = 256, }, { .name = "throttle.read_iops_device", .private = offsetof(struct throtl_grp, iops[READ]), .seq_show = tg_print_conf_uint, .write_string = tg_set_conf_uint, - .max_write_len = 256, }, { .name = "throttle.write_iops_device", .private = offsetof(struct throtl_grp, iops[WRITE]), .seq_show = tg_print_conf_uint, .write_string = tg_set_conf_uint, - .max_write_len = 256, }, { .name = "throttle.io_service_bytes", diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 744833b630c6..461187943392 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1838,7 +1838,6 @@ static struct cftype cfq_blkcg_files[] = { .flags = CFTYPE_ONLY_ON_ROOT, .seq_show = cfqg_print_leaf_weight_device, .write_string = cfqg_set_leaf_weight_device, - .max_write_len = 256, }, { .name = "weight", @@ -1853,7 +1852,6 @@ static struct cftype cfq_blkcg_files[] = { .flags = CFTYPE_NOT_ON_ROOT, .seq_show = cfqg_print_weight_device, .write_string = cfqg_set_weight_device, - .max_write_len = 256, }, { .name = "weight", @@ -1866,7 +1864,6 @@ static struct cftype cfq_blkcg_files[] = { .name = "leaf_weight_device", .seq_show = cfqg_print_leaf_weight_device, .write_string = cfqg_set_leaf_weight_device, - .max_write_len = 256, }, { .name = "leaf_weight", diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index c4350a82320b..63feaed83bc6 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -400,8 +400,9 @@ struct cftype { umode_t mode; /* - * If non-zero, defines the maximum length of string that can - * be passed to write_string; defaults to 64 + * The maximum length of string, excluding trailing nul, that can + * be passed to write_string. If < PAGE_SIZE-1, PAGE_SIZE-1 is + * assumed. */ size_t max_write_len; diff --git a/kernel/cgroup.c b/kernel/cgroup.c index eb002c622cd6..fde3633ef389 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2213,13 +2213,14 @@ static int cgroup_procs_write(struct cgroup_subsys_state *css, static int cgroup_release_agent_write(struct cgroup_subsys_state *css, struct cftype *cft, const char *buffer) { - BUILD_BUG_ON(sizeof(css->cgroup->root->release_agent_path) < PATH_MAX); - if (strlen(buffer) >= PATH_MAX) - return -EINVAL; + struct cgroupfs_root *root = css->cgroup->root; + + BUILD_BUG_ON(sizeof(root->release_agent_path) < PATH_MAX); if (!cgroup_lock_live_group(css->cgroup)) return -ENODEV; spin_lock(&release_agent_path_lock); - strcpy(css->cgroup->root->release_agent_path, buffer); + strlcpy(root->release_agent_path, buffer, + sizeof(root->release_agent_path)); spin_unlock(&release_agent_path_lock); mutex_unlock(&cgroup_mutex); return 0; @@ -2245,20 +2246,17 @@ static int cgroup_sane_behavior_show(struct seq_file *seq, void *v) return 0; } -/* A buffer size big enough for numbers or short strings */ -#define CGROUP_LOCAL_BUFFER_SIZE 64 - static ssize_t cgroup_file_write(struct file *file, const char __user *userbuf, size_t nbytes, loff_t *ppos) { struct cfent *cfe = __d_cfe(file->f_dentry); struct cftype *cft = __d_cft(file->f_dentry); struct cgroup_subsys_state *css = cfe->css; - size_t max_bytes = cft->max_write_len ?: CGROUP_LOCAL_BUFFER_SIZE - 1; + size_t max_bytes = max(cft->max_write_len, PAGE_SIZE); char *buf; int ret; - if (nbytes >= max_bytes) + if (nbytes > max_bytes) return -E2BIG; buf = kmalloc(nbytes + 1, GFP_KERNEL); @@ -3919,7 +3917,7 @@ static struct cftype cgroup_base_files[] = { .flags = CFTYPE_INSANE | CFTYPE_ONLY_ON_ROOT, .seq_show = cgroup_release_agent_show, .write_string = cgroup_release_agent_write, - .max_write_len = PATH_MAX, + .max_write_len = PATH_MAX - 1, }, { } /* terminate */ }; |