[PATCH v2] erofs-utils: mkfs: fix image reproducibility of `-E(all-)fragments`

[Gao Xiang]

The timestamp of the packed inode should be fixed to the build time.

Fixes: 9fa9b017f773 ("erofs-utils: mkfs: support fragments")
Signed-off-by: Gao Xiang <hsiang...@linux.alibaba.com>
---
change since v1:
 - fix time assignment (assign `i_mtime_nsec` too) [Hongbo];

 lib/inode.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/lib/inode.c b/lib/inode.c
index 7a10624..9095ebc 100644
--- a/lib/inode.c
+++ b/lib/inode.c
@@ -910,7 +910,8 @@ out:
        return 0;
 }
 
-static bool erofs_should_use_inode_extended(struct erofs_inode *inode)
+static bool erofs_should_use_inode_extended(struct erofs_inode *inode,
+                                           const char *path)
 {
        if (cfg.c_force_inodeversion == FORCE_INODE_EXTENDED)
                return true;
@@ -924,7 +925,8 @@ static bool erofs_should_use_inode_extended(struct 
erofs_inode *inode)
                return true;
        if (inode->i_nlink > USHRT_MAX)
                return true;
-       if ((inode->i_mtime != inode->sbi->build_time ||
+       if (path != EROFS_PACKED_INODE &&
+           (inode->i_mtime != inode->sbi->build_time ||
             inode->i_mtime_nsec != inode->sbi->build_time_nsec) &&
            !cfg.c_ignore_mtime)
                return true;
@@ -1016,6 +1018,11 @@ int __erofs_fill_inode(struct erofs_inode *inode, struct 
stat *st,
                erofs_err("gid overflow @ %s", path);
        inode->i_gid += cfg.c_gid_offset;
 
+       if (path == EROFS_PACKED_INODE) {
+               inode->i_mtime = sbi->build_time;
+               inode->i_mtime_nsec = sbi->build_time_nsec;
+               return 0;
+       }
        inode->i_mtime = st->st_mtime;
        inode->i_mtime_nsec = ST_MTIM_NSEC(st);
 
@@ -1029,7 +1036,6 @@ int __erofs_fill_inode(struct erofs_inode *inode, struct 
stat *st,
        default:
                break;
        }
-
        return 0;
 }
 
@@ -1065,7 +1071,7 @@ static int erofs_fill_inode(struct erofs_inode *inode, 
struct stat *st,
        if (!inode->i_srcpath)
                return -ENOMEM;
 
-       if (erofs_should_use_inode_extended(inode)) {
+       if (erofs_should_use_inode_extended(inode, path)) {
                if (cfg.c_force_inodeversion == FORCE_INODE_COMPACT) {
                        erofs_err("file %s cannot be in compact form",
                                  inode->i_srcpath);
@@ -1610,7 +1616,7 @@ static int erofs_rebuild_handle_inode(struct erofs_inode 
*inode,
        erofs_update_progressinfo("Processing %s ...", trimmed);
        free(trimmed);
 
-       if (erofs_should_use_inode_extended(inode)) {
+       if (erofs_should_use_inode_extended(inode, inode->i_srcpath)) {
                if (cfg.c_force_inodeversion == FORCE_INODE_COMPACT) {
                        erofs_err("file %s cannot be in compact form",
                                  inode->i_srcpath);
-- 
2.43.5