core: canonicalize bare-user xattrs

Previously we were erroring out if xattrs were provided in
non-canonical (e.g. unsorted) form all the way down to just
the bare-user path. But for archive repos and dirmeta we
canonicalized.

Canonicalize bare-user xattrs on both read and write consistently
instead of erroring.

Signed-off-by: Colin Walters <walters@verbum.org>
This commit is contained in:
Colin Walters 2025-02-25 14:14:19 -05:00
parent 0c55f68006
commit 37961d3d9e
4 changed files with 14 additions and 9 deletions

View File

@ -90,6 +90,7 @@ void _ostree_gfileinfo_to_stbuf (GFileInfo *file_info, struct stat *out_stbuf);
gboolean _ostree_gfileinfo_equal (GFileInfo *a, GFileInfo *b);
gboolean _ostree_stbuf_equal (struct stat *stbuf_a, struct stat *stbuf_b);
GFileInfo *_ostree_mode_uidgid_to_gfileinfo (mode_t mode, uid_t uid, gid_t gid);
GVariant *_ostree_canonicalize_xattrs (GVariant *xattrs);
gboolean _ostree_validate_structureof_xattrs (GVariant *xattrs, GError **error);
static inline void

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@ -43,7 +43,6 @@ G_STATIC_ASSERT (OSTREE_REPO_MODE_BARE_USER_ONLY == 3);
G_STATIC_ASSERT (OSTREE_REPO_MODE_BARE_SPLIT_XATTRS == 4);
static GBytes *variant_to_lenprefixed_buffer (GVariant *variant);
static GVariant *canonicalize_xattrs (GVariant *xattrs);
#define ALIGN_VALUE(this, boundary) \
((((unsigned long)(this)) + (((unsigned long)(boundary)) - 1)) \
@ -317,8 +316,8 @@ compare_xattrs (const void *a_pp, const void *b_pp)
}
// Sort xattrs by name
static GVariant *
canonicalize_xattrs (GVariant *xattrs)
GVariant *
_ostree_canonicalize_xattrs (GVariant *xattrs)
{
// We always need to provide data, so NULL is canonicalized to the empty array
if (xattrs == NULL)
@ -364,7 +363,7 @@ _ostree_file_header_new (GFileInfo *file_info, GVariant *xattrs)
symlink_target = "";
// We always sort the xattrs now to ensure everything is in normal/canonical form.
g_autoptr (GVariant) tmp_xattrs = canonicalize_xattrs (xattrs);
g_autoptr (GVariant) tmp_xattrs = _ostree_canonicalize_xattrs (xattrs);
g_autoptr (GVariant) ret
= g_variant_new ("(uuuus@a(ayay))", GUINT32_TO_BE (uid), GUINT32_TO_BE (gid),
@ -1153,7 +1152,7 @@ ostree_create_directory_metadata (GFileInfo *dir_info, GVariant *xattrs)
GVariant *ret_metadata = NULL;
// We always sort the xattrs now to ensure everything is in normal/canonical form.
g_autoptr (GVariant) tmp_xattrs = canonicalize_xattrs (xattrs);
g_autoptr (GVariant) tmp_xattrs = _ostree_canonicalize_xattrs (xattrs);
ret_metadata = g_variant_new (
"(uuu@a(ayay))", GUINT32_TO_BE (g_file_info_get_attribute_uint32 (dir_info, "unix::uid")),

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@ -140,9 +140,11 @@ _ostree_write_bareuser_metadata (int fd, guint32 uid, guint32 gid, guint32 mode,
GError **error)
{
GLNX_AUTO_PREFIX_ERROR ("Writing bareuser metadata", error);
if (xattrs != NULL && !_ostree_validate_structureof_xattrs (xattrs, error))
return FALSE;
g_autoptr (GVariant) filemeta = create_file_metadata (uid, gid, mode, xattrs);
// Like we do elsewhere, ensure xattrs are in canonical form. We don't strictly need
// this because we don't actually provide this data directly as input to a checksum today,
// but it's good hygeine to do so.
g_autoptr (GVariant) tmp_xattrs = _ostree_canonicalize_xattrs (xattrs);
g_autoptr (GVariant) filemeta = create_file_metadata (uid, gid, mode, tmp_xattrs);
if (TEMP_FAILURE_RETRY (fsetxattr (fd, "user.ostreemeta", (char *)g_variant_get_data (filemeta),
g_variant_get_size (filemeta), 0))

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@ -4098,7 +4098,10 @@ _ostree_repo_load_file_bare (OstreeRepo *self, const char *checksum, int *out_fd
g_autoptr (GVariant) metadata = g_variant_ref_sink (
g_variant_new_from_bytes (OSTREE_FILEMETA_GVARIANT_FORMAT, bytes, FALSE));
ret_xattrs = filemeta_to_stat (&stbuf, metadata);
g_autoptr (GVariant) read_xattrs = filemeta_to_stat (&stbuf, metadata);
// Old versions of ostree may have written these xattrs in non-canonical form.
// In order to aid comparisons, let's canonicalize here.
ret_xattrs = _ostree_canonicalize_xattrs (read_xattrs);
if (S_ISLNK (stbuf.st_mode))
{
if (out_symlink)