diff options
Diffstat (limited to 'fs/notify/inotify/inotify_user.c')
-rw-r--r-- | fs/notify/inotify/inotify_user.c | 117 |
1 files changed, 43 insertions, 74 deletions
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index 69d1ea3d292a..7cc7d3fb1862 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -30,7 +30,7 @@ #include <linux/inotify.h> #include <linux/kernel.h> /* roundup() */ #include <linux/namei.h> /* LOOKUP_FOLLOW */ -#include <linux/sched.h> /* struct user */ +#include <linux/sched/signal.h> #include <linux/slab.h> /* struct kmem_cache */ #include <linux/syscalls.h> #include <linux/types.h> @@ -44,12 +44,10 @@ #include <asm/ioctls.h> -/* these are configurable via /proc/sys/fs/inotify/ */ -static int inotify_max_user_instances __read_mostly; +/* configurable via /proc/sys/fs/inotify/ */ static int inotify_max_queued_events __read_mostly; -static int inotify_max_user_watches __read_mostly; -static struct kmem_cache *inotify_inode_mark_cachep __read_mostly; +struct kmem_cache *inotify_inode_mark_cachep __read_mostly; #ifdef CONFIG_SYSCTL @@ -60,7 +58,7 @@ static int zero; struct ctl_table inotify_table[] = { { .procname = "max_user_instances", - .data = &inotify_max_user_instances, + .data = &init_user_ns.ucount_max[UCOUNT_INOTIFY_INSTANCES], .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_minmax, @@ -68,7 +66,7 @@ struct ctl_table inotify_table[] = { }, { .procname = "max_user_watches", - .data = &inotify_max_user_watches, + .data = &init_user_ns.ucount_max[UCOUNT_INOTIFY_WATCHES], .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_minmax, @@ -397,21 +395,6 @@ static struct inotify_inode_mark *inotify_idr_find(struct fsnotify_group *group, return i_mark; } -static void do_inotify_remove_from_idr(struct fsnotify_group *group, - struct inotify_inode_mark *i_mark) -{ - struct idr *idr = &group->inotify_data.idr; - spinlock_t *idr_lock = &group->inotify_data.idr_lock; - int wd = i_mark->wd; - - assert_spin_locked(idr_lock); - - idr_remove(idr, wd); - - /* removed from the idr, drop that ref */ - fsnotify_put_mark(&i_mark->fsn_mark); -} - /* * Remove the mark from the idr (if present) and drop the reference * on the mark because it was in the idr. @@ -419,6 +402,7 @@ static void do_inotify_remove_from_idr(struct fsnotify_group *group, static void inotify_remove_from_idr(struct fsnotify_group *group, struct inotify_inode_mark *i_mark) { + struct idr *idr = &group->inotify_data.idr; spinlock_t *idr_lock = &group->inotify_data.idr_lock; struct inotify_inode_mark *found_i_mark = NULL; int wd; @@ -431,18 +415,16 @@ static void inotify_remove_from_idr(struct fsnotify_group *group, * if it wasn't.... */ if (wd == -1) { - WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p" - " i_mark->inode=%p\n", __func__, i_mark, i_mark->wd, - i_mark->fsn_mark.group, i_mark->fsn_mark.inode); + WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p\n", + __func__, i_mark, i_mark->wd, i_mark->fsn_mark.group); goto out; } /* Lets look in the idr to see if we find it */ found_i_mark = inotify_idr_find_locked(group, wd); if (unlikely(!found_i_mark)) { - WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p" - " i_mark->inode=%p\n", __func__, i_mark, i_mark->wd, - i_mark->fsn_mark.group, i_mark->fsn_mark.inode); + WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p\n", + __func__, i_mark, i_mark->wd, i_mark->fsn_mark.group); goto out; } @@ -453,35 +435,33 @@ static void inotify_remove_from_idr(struct fsnotify_group *group, */ if (unlikely(found_i_mark != i_mark)) { WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p " - "mark->inode=%p found_i_mark=%p found_i_mark->wd=%d " - "found_i_mark->group=%p found_i_mark->inode=%p\n", - __func__, i_mark, i_mark->wd, i_mark->fsn_mark.group, - i_mark->fsn_mark.inode, found_i_mark, found_i_mark->wd, - found_i_mark->fsn_mark.group, - found_i_mark->fsn_mark.inode); + "found_i_mark=%p found_i_mark->wd=%d " + "found_i_mark->group=%p\n", __func__, i_mark, + i_mark->wd, i_mark->fsn_mark.group, found_i_mark, + found_i_mark->wd, found_i_mark->fsn_mark.group); goto out; } /* * One ref for being in the idr - * one ref held by the caller trying to kill us * one ref grabbed by inotify_idr_find */ - if (unlikely(atomic_read(&i_mark->fsn_mark.refcnt) < 3)) { - printk(KERN_ERR "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p" - " i_mark->inode=%p\n", __func__, i_mark, i_mark->wd, - i_mark->fsn_mark.group, i_mark->fsn_mark.inode); + if (unlikely(atomic_read(&i_mark->fsn_mark.refcnt) < 2)) { + printk(KERN_ERR "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p\n", + __func__, i_mark, i_mark->wd, i_mark->fsn_mark.group); /* we can't really recover with bad ref cnting.. */ BUG(); } - do_inotify_remove_from_idr(group, i_mark); + idr_remove(idr, wd); + /* Removed from the idr, drop that ref. */ + fsnotify_put_mark(&i_mark->fsn_mark); out: + i_mark->wd = -1; + spin_unlock(idr_lock); /* match the ref taken by inotify_idr_find_locked() */ if (found_i_mark) fsnotify_put_mark(&found_i_mark->fsn_mark); - i_mark->wd = -1; - spin_unlock(idr_lock); } /* @@ -494,23 +474,13 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, /* Queue ignore event for the watch */ inotify_handle_event(group, NULL, fsn_mark, NULL, FS_IN_IGNORED, - NULL, FSNOTIFY_EVENT_NONE, NULL, 0); + NULL, FSNOTIFY_EVENT_NONE, NULL, 0, NULL); i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); /* remove this mark from the idr */ inotify_remove_from_idr(group, i_mark); - atomic_dec(&group->inotify_data.user->inotify_watches); -} - -/* ding dong the mark is dead */ -static void inotify_free_mark(struct fsnotify_mark *fsn_mark) -{ - struct inotify_inode_mark *i_mark; - - i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); - - kmem_cache_free(inotify_inode_mark_cachep, i_mark); + dec_inotify_watches(group->inotify_data.ucounts); } static int inotify_update_existing_watch(struct fsnotify_group *group, @@ -526,21 +496,19 @@ static int inotify_update_existing_watch(struct fsnotify_group *group, mask = inotify_arg_to_mask(arg); - fsn_mark = fsnotify_find_inode_mark(group, inode); + fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, group); if (!fsn_mark) return -ENOENT; i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); spin_lock(&fsn_mark->lock); - old_mask = fsn_mark->mask; if (add) - fsnotify_set_mark_mask_locked(fsn_mark, (fsn_mark->mask | mask)); + fsn_mark->mask |= mask; else - fsnotify_set_mark_mask_locked(fsn_mark, mask); + fsn_mark->mask = mask; new_mask = fsn_mark->mask; - spin_unlock(&fsn_mark->lock); if (old_mask != new_mask) { @@ -551,7 +519,7 @@ static int inotify_update_existing_watch(struct fsnotify_group *group, /* update the inode with this new fsn_mark */ if (dropped || do_inode) - fsnotify_recalc_inode_mask(inode); + fsnotify_recalc_mask(inode->i_fsnotify_marks); } @@ -580,29 +548,29 @@ static int inotify_new_watch(struct fsnotify_group *group, if (unlikely(!tmp_i_mark)) return -ENOMEM; - fsnotify_init_mark(&tmp_i_mark->fsn_mark, inotify_free_mark); + fsnotify_init_mark(&tmp_i_mark->fsn_mark, group); tmp_i_mark->fsn_mark.mask = mask; tmp_i_mark->wd = -1; - ret = -ENOSPC; - if (atomic_read(&group->inotify_data.user->inotify_watches) >= inotify_max_user_watches) - goto out_err; - ret = inotify_add_to_idr(idr, idr_lock, tmp_i_mark); if (ret) goto out_err; + /* increment the number of watches the user has */ + if (!inc_inotify_watches(group->inotify_data.ucounts)) { + inotify_remove_from_idr(group, tmp_i_mark); + ret = -ENOSPC; + goto out_err; + } + /* we are on the idr, now get on the inode */ - ret = fsnotify_add_mark_locked(&tmp_i_mark->fsn_mark, group, inode, - NULL, 0); + ret = fsnotify_add_mark_locked(&tmp_i_mark->fsn_mark, inode, NULL, 0); if (ret) { /* we failed to get on the inode, get off the idr */ inotify_remove_from_idr(group, tmp_i_mark); goto out_err; } - /* increment the number of watches the user has */ - atomic_inc(&group->inotify_data.user->inotify_watches); /* return the watch descriptor for this new mark */ ret = tmp_i_mark->wd; @@ -653,10 +621,11 @@ static struct fsnotify_group *inotify_new_group(unsigned int max_events) spin_lock_init(&group->inotify_data.idr_lock); idr_init(&group->inotify_data.idr); - group->inotify_data.user = get_current_user(); + group->inotify_data.ucounts = inc_ucount(current_user_ns(), + current_euid(), + UCOUNT_INOTIFY_INSTANCES); - if (atomic_inc_return(&group->inotify_data.user->inotify_devs) > - inotify_max_user_instances) { + if (!group->inotify_data.ucounts) { fsnotify_destroy_group(group); return ERR_PTR(-EMFILE); } @@ -819,8 +788,8 @@ static int __init inotify_user_setup(void) inotify_inode_mark_cachep = KMEM_CACHE(inotify_inode_mark, SLAB_PANIC); inotify_max_queued_events = 16384; - inotify_max_user_instances = 128; - inotify_max_user_watches = 8192; + init_user_ns.ucount_max[UCOUNT_INOTIFY_INSTANCES] = 128; + init_user_ns.ucount_max[UCOUNT_INOTIFY_WATCHES] = 8192; return 0; } |