5.15-stable review patch. If anyone has any objections, please let me know.
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From: Amir Goldstein amir73il@gmail.com
[ Upstream commit 3982534ba5ce45e890b2f5ef5e7372c1accd14c7 ]
In the special case of FAN_RENAME event, we record both the old and new parent and name.
Link: https://lore.kernel.org/r/20211129201537.1932819-9-amir73il@gmail.com Signed-off-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Jan Kara jack@suse.cz Signed-off-by: Chuck Lever chuck.lever@oracle.com --- fs/notify/fanotify/fanotify.c | 42 +++++++++++++++++++++++++++++++---- include/uapi/linux/fanotify.h | 2 ++ 2 files changed, 40 insertions(+), 4 deletions(-)
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 5f184b2d6ea7c..db81eab905442 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -592,21 +592,28 @@ static struct fanotify_event *fanotify_alloc_name_event(struct inode *dir, __kernel_fsid_t *fsid, const struct qstr *name, struct inode *child, + struct dentry *moved, unsigned int *hash, gfp_t gfp) { struct fanotify_name_event *fne; struct fanotify_info *info; struct fanotify_fh *dfh, *ffh; + struct inode *dir2 = moved ? d_inode(moved->d_parent) : NULL; + const struct qstr *name2 = moved ? &moved->d_name : NULL; unsigned int dir_fh_len = fanotify_encode_fh_len(dir); + unsigned int dir2_fh_len = fanotify_encode_fh_len(dir2); unsigned int child_fh_len = fanotify_encode_fh_len(child); unsigned long name_len = name ? name->len : 0; + unsigned long name2_len = name2 ? name2->len : 0; unsigned int len, size;
/* Reserve terminating null byte even for empty name */ - size = sizeof(*fne) + name_len + 1; + size = sizeof(*fne) + name_len + name2_len + 2; if (dir_fh_len) size += FANOTIFY_FH_HDR_LEN + dir_fh_len; + if (dir2_fh_len) + size += FANOTIFY_FH_HDR_LEN + dir2_fh_len; if (child_fh_len) size += FANOTIFY_FH_HDR_LEN + child_fh_len; fne = kmalloc(size, gfp); @@ -623,6 +630,11 @@ static struct fanotify_event *fanotify_alloc_name_event(struct inode *dir, len = fanotify_encode_fh(dfh, dir, dir_fh_len, hash, 0); fanotify_info_set_dir_fh(info, len); } + if (dir2_fh_len) { + dfh = fanotify_info_dir2_fh(info); + len = fanotify_encode_fh(dfh, dir2, dir2_fh_len, hash, 0); + fanotify_info_set_dir2_fh(info, len); + } if (child_fh_len) { ffh = fanotify_info_file_fh(info); len = fanotify_encode_fh(ffh, child, child_fh_len, hash, 0); @@ -632,11 +644,22 @@ static struct fanotify_event *fanotify_alloc_name_event(struct inode *dir, fanotify_info_copy_name(info, name); *hash ^= full_name_hash((void *)name_len, name->name, name_len); } + if (name2_len) { + fanotify_info_copy_name2(info, name2); + *hash ^= full_name_hash((void *)name2_len, name2->name, + name2_len); + }
pr_debug("%s: size=%u dir_fh_len=%u child_fh_len=%u name_len=%u name='%.*s'\n", __func__, size, dir_fh_len, child_fh_len, info->name_len, info->name_len, fanotify_info_name(info));
+ if (dir2_fh_len) { + pr_debug("%s: dir2_fh_len=%u name2_len=%u name2='%.*s'\n", + __func__, dir2_fh_len, info->name2_len, + info->name2_len, fanotify_info_name2(info)); + } + return &fne->fae; }
@@ -692,6 +715,7 @@ static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, struct inode *dirid = fanotify_dfid_inode(mask, data, data_type, dir); const struct path *path = fsnotify_data_path(data, data_type); struct mem_cgroup *old_memcg; + struct dentry *moved = NULL; struct inode *child = NULL; bool name_event = false; unsigned int hash = 0; @@ -727,6 +751,15 @@ static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, } else if ((mask & ALL_FSNOTIFY_DIRENT_EVENTS) || !ondir) { name_event = true; } + + /* + * In the special case of FAN_RENAME event, we record both + * old and new parent+name. + * 'dirid' and 'file_name' are the old parent+name and + * 'moved' has the new parent+name. + */ + if (mask & FAN_RENAME) + moved = fsnotify_data_dentry(data, data_type); }
/* @@ -748,9 +781,9 @@ static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, } else if (fanotify_is_error_event(mask)) { event = fanotify_alloc_error_event(group, fsid, data, data_type, &hash); - } else if (name_event && (file_name || child)) { - event = fanotify_alloc_name_event(id, fsid, file_name, child, - &hash, gfp); + } else if (name_event && (file_name || moved || child)) { + event = fanotify_alloc_name_event(dirid, fsid, file_name, child, + moved, &hash, gfp); } else if (fid_mode) { event = fanotify_alloc_fid_event(id, fsid, &hash, gfp); } else { @@ -860,6 +893,7 @@ static int fanotify_handle_event(struct fsnotify_group *group, u32 mask, BUILD_BUG_ON(FAN_OPEN_EXEC != FS_OPEN_EXEC); 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(HWEIGHT32(ALL_FANOTIFY_EVENT_BITS) != 20);
diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h index 60f73639a896a..9d0e2dc5767b5 100644 --- a/include/uapi/linux/fanotify.h +++ b/include/uapi/linux/fanotify.h @@ -28,6 +28,8 @@
#define FAN_EVENT_ON_CHILD 0x08000000 /* Interested in child events */
+#define FAN_RENAME 0x10000000 /* File was renamed */ + #define FAN_ONDIR 0x40000000 /* Event occurred against dir */
/* helper events */