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Diffstat (limited to 'fs/notify/fanotify/fanotify.c')
-rw-r--r--fs/notify/fanotify/fanotify.c119
1 files changed, 79 insertions, 40 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 9dac7f6e72d2..bfe884d624e7 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -1,6 +1,5 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/fanotify.h>
-#include <linux/fdtable.h>
#include <linux/fsnotify_backend.h>
#include <linux/init.h>
#include <linux/jiffies.h>
@@ -29,12 +28,6 @@ static unsigned int fanotify_hash_path(const struct path *path)
hash_ptr(path->mnt, FANOTIFY_EVENT_HASH_BITS);
}
-static inline bool fanotify_fsid_equal(__kernel_fsid_t *fsid1,
- __kernel_fsid_t *fsid2)
-{
- return fsid1->val[0] == fsid2->val[0] && fsid1->val[1] == fsid2->val[1];
-}
-
static unsigned int fanotify_hash_fsid(__kernel_fsid_t *fsid)
{
return hash_32(fsid->val[0], FANOTIFY_EVENT_HASH_BITS) ^
@@ -173,6 +166,8 @@ static bool fanotify_should_merge(struct fanotify_event *old,
case FANOTIFY_EVENT_TYPE_FS_ERROR:
return fanotify_error_event_equal(FANOTIFY_EE(old),
FANOTIFY_EE(new));
+ case FANOTIFY_EVENT_TYPE_MNT:
+ return false;
default:
WARN_ON_ONCE(1);
}
@@ -230,12 +225,14 @@ static int fanotify_get_response(struct fsnotify_group *group,
struct fanotify_perm_event *event,
struct fsnotify_iter_info *iter_info)
{
- int ret;
+ int ret, errno;
pr_debug("%s: group=%p event=%p\n", __func__, group, event);
- ret = wait_event_killable(group->fanotify_data.access_waitq,
- event->state == FAN_EVENT_ANSWERED);
+ ret = wait_event_state(group->fanotify_data.access_waitq,
+ event->state == FAN_EVENT_ANSWERED,
+ (TASK_KILLABLE|TASK_FREEZABLE));
+
/* Signal pending? */
if (ret < 0) {
spin_lock(&group->notification_lock);
@@ -267,14 +264,23 @@ static int fanotify_get_response(struct fsnotify_group *group,
ret = 0;
break;
case FAN_DENY:
+ /* Check custom errno from pre-content events */
+ errno = fanotify_get_response_errno(event->response);
+ if (errno) {
+ ret = -errno;
+ break;
+ }
+ fallthrough;
default:
ret = -EPERM;
}
/* Check if the response should be audited */
- if (event->response & FAN_AUDIT)
- audit_fanotify(event->response & ~FAN_AUDIT,
- &event->audit_rule);
+ if (event->response & FAN_AUDIT) {
+ u32 response = event->response &
+ (FANOTIFY_RESPONSE_ACCESS | FANOTIFY_RESPONSE_FLAGS);
+ audit_fanotify(response & ~FAN_AUDIT, &event->audit_rule);
+ }
pr_debug("%s: group=%p event=%p about to return ret=%d\n", __func__,
group, event, ret);
@@ -308,7 +314,10 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
pr_debug("%s: report_mask=%x mask=%x data=%p data_type=%d\n",
__func__, iter_info->report_mask, event_mask, data, data_type);
- if (!fid_mode) {
+ if (FAN_GROUP_FLAG(group, FAN_REPORT_MNT)) {
+ if (data_type != FSNOTIFY_EVENT_MNT)
+ return 0;
+ } else if (!fid_mode) {
/* Do we have path to open a file descriptor? */
if (!path)
return 0;
@@ -406,7 +415,7 @@ static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode,
{
int dwords, type = 0;
char *ext_buf = NULL;
- void *buf = fh->buf;
+ void *buf = fh + 1;
int err;
fh->type = FILEID_ROOT;
@@ -445,7 +454,13 @@ static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode,
dwords = fh_len >> 2;
type = exportfs_encode_fid(inode, buf, &dwords);
err = -EINVAL;
- if (type <= 0 || type == FILEID_INVALID || fh_len != dwords << 2)
+ /*
+ * Unlike file_handle, type and len of struct fanotify_fh are u8.
+ * Traditionally, filesystem return handle_type < 0xff, but there
+ * is no enforecement for that in vfs.
+ */
+ BUILD_BUG_ON(MAX_HANDLE_SZ > 0xff || FILEID_INVALID > 0xff);
+ if (type <= 0 || type >= FILEID_INVALID || fh_len != dwords << 2)
goto out_err;
fh->type = type;
@@ -553,9 +568,27 @@ static struct fanotify_event *fanotify_alloc_path_event(const struct path *path,
return &pevent->fae;
}
-static struct fanotify_event *fanotify_alloc_perm_event(const struct path *path,
+static struct fanotify_event *fanotify_alloc_mnt_event(u64 mnt_id, gfp_t gfp)
+{
+ struct fanotify_mnt_event *pevent;
+
+ pevent = kmem_cache_alloc(fanotify_mnt_event_cachep, gfp);
+ if (!pevent)
+ return NULL;
+
+ pevent->fae.type = FANOTIFY_EVENT_TYPE_MNT;
+ pevent->mnt_id = mnt_id;
+
+ return &pevent->fae;
+}
+
+static struct fanotify_event *fanotify_alloc_perm_event(const void *data,
+ int data_type,
gfp_t gfp)
{
+ const struct path *path = fsnotify_data_path(data, data_type);
+ const struct file_range *range =
+ fsnotify_data_file_range(data, data_type);
struct fanotify_perm_event *pevent;
pevent = kmem_cache_alloc(fanotify_perm_event_cachep, gfp);
@@ -569,6 +602,9 @@ static struct fanotify_event *fanotify_alloc_perm_event(const struct path *path,
pevent->hdr.len = 0;
pevent->state = FAN_EVENT_INIT;
pevent->path = *path;
+ /* NULL ppos means no range info */
+ pevent->ppos = range ? &range->pos : NULL;
+ pevent->count = range ? range->count : 0;
path_get(path);
return &pevent->fae;
@@ -720,6 +756,7 @@ static struct fanotify_event *fanotify_alloc_event(
fid_mode);
struct inode *dirid = fanotify_dfid_inode(mask, data, data_type, dir);
const struct path *path = fsnotify_data_path(data, data_type);
+ u64 mnt_id = fsnotify_data_mnt_id(data, data_type);
struct mem_cgroup *old_memcg;
struct dentry *moved = NULL;
struct inode *child = NULL;
@@ -806,7 +843,7 @@ static struct fanotify_event *fanotify_alloc_event(
old_memcg = set_active_memcg(group->memcg);
if (fanotify_is_perm_event(mask)) {
- event = fanotify_alloc_perm_event(path, gfp);
+ event = fanotify_alloc_perm_event(data, data_type, gfp);
} else if (fanotify_is_error_event(mask)) {
event = fanotify_alloc_error_event(group, fsid, data,
data_type, &hash);
@@ -815,8 +852,12 @@ static struct fanotify_event *fanotify_alloc_event(
moved, &hash, gfp);
} else if (fid_mode) {
event = fanotify_alloc_fid_event(id, fsid, &hash, gfp);
- } else {
+ } else if (path) {
event = fanotify_alloc_path_event(path, &hash, gfp);
+ } else if (mnt_id) {
+ event = fanotify_alloc_mnt_event(mnt_id, gfp);
+ } else {
+ WARN_ON_ONCE(1);
}
if (!event)
@@ -838,9 +879,8 @@ out:
}
/*
- * Get cached fsid of the filesystem containing the object from any connector.
- * All connectors are supposed to have the same fsid, but we do not verify that
- * here.
+ * Get cached fsid of the filesystem containing the object from any mark.
+ * All marks are supposed to have the same fsid, but we do not verify that here.
*/
static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info)
{
@@ -849,18 +889,11 @@ static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info)
__kernel_fsid_t fsid = {};
fsnotify_foreach_iter_mark_type(iter_info, mark, type) {
- struct fsnotify_mark_connector *conn;
-
- conn = READ_ONCE(mark->connector);
- /* Mark is just getting destroyed or created? */
- if (!conn)
- continue;
- if (!(conn->flags & FSNOTIFY_CONN_FLAG_HAS_FSID))
+ if (!(mark->flags & FSNOTIFY_MARK_FLAG_HAS_FSID))
continue;
- /* Pairs with smp_wmb() in fsnotify_add_mark_list() */
- smp_rmb();
- fsid = conn->fsid;
- if (WARN_ON_ONCE(!fsid.val[0] && !fsid.val[1]))
+ fsid = FANOTIFY_MARK(mark)->fsid;
+ if (!(mark->flags & FSNOTIFY_MARK_FLAG_WEAK_FSID) &&
+ WARN_ON_ONCE(!fsid.val[0] && !fsid.val[1]))
continue;
return fsid;
}
@@ -922,8 +955,9 @@ static int fanotify_handle_event(struct fsnotify_group *group, u32 mask,
BUILD_BUG_ON(FAN_OPEN_EXEC_PERM != FS_OPEN_EXEC_PERM);
BUILD_BUG_ON(FAN_FS_ERROR != FS_ERROR);
BUILD_BUG_ON(FAN_RENAME != FS_RENAME);
+ BUILD_BUG_ON(FAN_PRE_ACCESS != FS_PRE_ACCESS);
- BUILD_BUG_ON(HWEIGHT32(ALL_FANOTIFY_EVENT_BITS) != 21);
+ BUILD_BUG_ON(HWEIGHT32(ALL_FANOTIFY_EVENT_BITS) != 24);
mask = fanotify_group_event_mask(group, iter_info, &match_mask,
mask, data, data_type, dir);
@@ -942,12 +976,8 @@ static int fanotify_handle_event(struct fsnotify_group *group, u32 mask,
return 0;
}
- if (FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS)) {
+ if (FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS))
fsid = fanotify_get_fsid(iter_info);
- /* Racing with mark destruction or creation? */
- if (!fsid.val[0] && !fsid.val[1])
- return 0;
- }
event = fanotify_alloc_event(group, mask, data, data_type, dir,
file_name, &fsid, match_mask);
@@ -985,6 +1015,7 @@ finish:
static void fanotify_free_group_priv(struct fsnotify_group *group)
{
+ put_user_ns(group->user_ns);
kfree(group->fanotify_data.merge_hash);
if (group->fanotify_data.ucounts)
dec_ucount(group->fanotify_data.ucounts,
@@ -1028,6 +1059,11 @@ static void fanotify_free_error_event(struct fsnotify_group *group,
mempool_free(fee, &group->fanotify_data.error_events_pool);
}
+static void fanotify_free_mnt_event(struct fanotify_event *event)
+{
+ kmem_cache_free(fanotify_mnt_event_cachep, FANOTIFY_ME(event));
+}
+
static void fanotify_free_event(struct fsnotify_group *group,
struct fsnotify_event *fsn_event)
{
@@ -1054,6 +1090,9 @@ static void fanotify_free_event(struct fsnotify_group *group,
case FANOTIFY_EVENT_TYPE_FS_ERROR:
fanotify_free_error_event(group, event);
break;
+ case FANOTIFY_EVENT_TYPE_MNT:
+ fanotify_free_mnt_event(event);
+ break;
default:
WARN_ON_ONCE(1);
}
@@ -1068,7 +1107,7 @@ static void fanotify_freeing_mark(struct fsnotify_mark *mark,
static void fanotify_free_mark(struct fsnotify_mark *fsn_mark)
{
- kmem_cache_free(fanotify_mark_cache, fsn_mark);
+ kmem_cache_free(fanotify_mark_cache, FANOTIFY_MARK(fsn_mark));
}
const struct fsnotify_ops fanotify_fsnotify_ops = {
generated by cgit (git 2.34.1) at 2025-12-25 14:33:29 +0000