* [PATCH v6 2/4] initramfs: add file metadata
2026-11-05 19:37 [PATCH v6 0/4] initramfs: add support for xattrs in the initial ram disk Danny Hu
2026-11-05 19:37 ` [PATCH v6 1/4] ima: skip algorithm availability check until initramfs unpacking is finished Danny Hu
@ 2026-11-05 19:37 ` Danny Hu
2026-11-05 19:37 ` [PATCH v6 3/4] initramfs: read metadata from special file METADATA!!! Danny Hu
2026-11-05 19:37 ` [PATCH v6 4/4] gen_init_cpio: add support for file metadata Danny Hu
3 siblings, 0 replies; 5+ messages in thread
From: Danny Hu @ 2026-11-05 19:37 UTC (permalink / raw)
To: Alexander Viro, Christian Brauner
Cc: Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Eric Snowberg,
Jan Kara, Victor Kamensky, Taras Kondratiuk, Zheng Zengkai,
zhangguangzhi, Danny Hu, Jason Yan, silviu.vlasceanu, hpa, arnd,
james.w.mcmechan, niveditas98, pierre, julien, kbharathi,
alexandr.lobakin, linux-fsdevel, linux-integrity,
linux-security-module, linux-kbuild, initramfs, linux-api,
linux-kernel, bug-cpio
From: Mimi Zohar <zohar@linux.vnet.ibm.com>
This patch adds metadata to a file from a supplied buffer. The buffer might
contains multiple metadata records. The format of each record is:
<metadata len (ASCII, 8 chars)><version><type><metadata>
For now, only the TYPE_XATTR metadata type is supported. The specific
format of this metadata type is:
<xattr #N name>\0<xattr #N value>
[kamensky: fixed restoring of xattrs for symbolic links by using
sys_lsetxattr() instead of sys_setxattr()]
[sassu: removed state management, kept only do_setxattrs(), added support
for generic file metadata, replaced sys_lsetxattr() with
vfs_setxattr(), added check for entry_size, added check for
hdr->c_size, replaced strlen() with strnlen(); moved do_setxattrs()
before do_name()]
[zhangguangzhi: fix checkpatch warning EMBEDDED_FILENAME in
include/linux/initramfs.h]
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Victor Kamensky <kamensky@cisco.com>
Signed-off-by: Taras Kondratiuk <takondra@cisco.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Tianxing Zhang <zhangtianxing3@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: zhoushuiqing <zhoushuiqing2@huawei.com>
Signed-off-by: zhangguangzhi <zhangguangzhi3@huawei.com>
Signed-off-by: Danny Hu <dannyhu@arista.com>
---
Changes in v6:
- Document lack of support for POSIX ACL restoration. The main use case is to
restore security.ima xattr for IMA use. POSIX ACL support is out of scope
for this patchset
- Check xattr name and value lengths to ensure they are valid and do not
exceed the limit
- Compare metadata header and record sizes against the remaining buffer
length to avoid pointer arithmetic overflow in bounds checks
- Use the kernel u32 type instead of uint32_t
Changes in v5:
- For debug print in do_setxattrs(), use print_hex_dump_debug() rather
than printing the xattr value as a string
- Use u32 metadata record lengths and reject records smaller than their
header
include/linux/initramfs.h | 19 +++++++
init/initramfs.c | 103 +++++++++++++++++++++++++++++++++++++-
2 files changed, 121 insertions(+), 1 deletion(-)
create mode 100644 include/linux/initramfs.h
diff --git a/include/linux/initramfs.h b/include/linux/initramfs.h
new file mode 100644
index 000000000000..9b3839dc88a1
--- /dev/null
+++ b/include/linux/initramfs.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Include file for file metadata in the initial ram disk.
+ */
+#ifndef _LINUX_INITRAMFS_H
+#define _LINUX_INITRAMFS_H
+
+#define METADATA_FILENAME "METADATA!!!"
+
+enum metadata_types { TYPE_NONE, TYPE_XATTR, TYPE__LAST };
+
+struct metadata_hdr {
+ char c_size[8]; /* total size including c_size field */
+ char c_version; /* header version */
+ char c_type; /* metadata type */
+ char c_metadata[]; /* metadata */
+} __packed;
+
+#endif /*LINUX_INITRAMFS_H*/
diff --git a/init/initramfs.c b/init/initramfs.c
index ebddde9c8f0d..d206624d1160 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -10,7 +10,9 @@
#include <linux/hex.h>
#include <linux/init.h>
#include <linux/init_syscalls.h>
+#include <linux/initramfs.h>
#include <linux/kstrtox.h>
+#include <linux/limits.h>
#include <linux/memblock.h>
#include <linux/mm.h>
#include <linux/namei.h>
@@ -22,6 +24,7 @@
#include <linux/types.h>
#include <linux/umh.h>
#include <linux/utime.h>
+#include <linux/xattr.h>
#include <asm/byteorder.h>
@@ -189,7 +192,7 @@ static __initdata time64_t mtime;
static __initdata unsigned long ino, major, minor, nlink;
static __initdata umode_t mode;
-static __initdata unsigned long body_len, name_len;
+static __initdata unsigned long body_len, name_len, metadata_len;
static __initdata uid_t uid;
static __initdata gid_t gid;
static __initdata unsigned rdev;
@@ -264,6 +267,7 @@ static void __init read_into(char *buf, unsigned size, enum state next)
}
static __initdata char *header_buf, *symlink_buf, *name_buf;
+static __initdata char *metadata_buf;
static int __init do_start(void)
{
@@ -365,6 +369,103 @@ static int __init maybe_link(void)
return 0;
}
+static int __init do_setxattrs(char *pathname, char *buf, size_t size)
+{
+ struct path path;
+ char *xattr_name, *xattr_value;
+ u32 xattr_name_size, xattr_value_size;
+ int ret;
+
+ xattr_name = buf;
+ xattr_name_size = strnlen(xattr_name, size);
+ if (xattr_name_size == size) {
+ error("malformed xattrs");
+ return -EINVAL;
+ }
+
+ if (!xattr_name_size || xattr_name_size > XATTR_NAME_MAX) {
+ error("invalid xattr name length");
+ return -EINVAL;
+ }
+
+ xattr_value = xattr_name + xattr_name_size + 1;
+ xattr_value_size = buf + size - xattr_value;
+ if (xattr_value_size > XATTR_SIZE_MAX) {
+ error("xattr value exceeds size limit");
+ return -EINVAL;
+ }
+
+ ret = kern_path(pathname, 0, &path);
+ if (!ret) {
+ /*
+ * POSIX ACL restoration is currently unsupported.
+ * vfs_setxattr() rejects POSIX ACL xattrs with -EOPNOTSUPP.
+ */
+ ret = vfs_setxattr(&nop_mnt_idmap, path.dentry, xattr_name, xattr_value,
+ xattr_value_size, 0);
+
+ path_put(&path);
+ }
+
+ pr_debug("%s: %s size: %u (ret: %d)\n", pathname, xattr_name,
+ xattr_value_size, ret);
+ print_hex_dump_debug("xattr value: ", DUMP_PREFIX_OFFSET,
+ 16, 1, xattr_value, xattr_value_size, false);
+
+ return ret;
+}
+
+static int __init __maybe_unused do_parse_metadata(char *pathname)
+{
+ char *buf = metadata_buf;
+ char *bufend = metadata_buf + metadata_len;
+ struct metadata_hdr *hdr;
+ char str[sizeof(hdr->c_size) + 1];
+ u32 entry_size;
+
+ if (!metadata_len)
+ return 0;
+
+ str[sizeof(hdr->c_size)] = 0;
+
+ while (buf < bufend) {
+ int ret;
+
+ if (bufend - buf < sizeof(*hdr)) {
+ error("malformed metadata");
+ break;
+ }
+
+ hdr = (struct metadata_hdr *)buf;
+ if (hdr->c_version != 1) {
+ pr_debug("Unsupported header version\n");
+ break;
+ }
+
+ memcpy(str, hdr->c_size, sizeof(hdr->c_size));
+ ret = kstrtou32(str, 16, &entry_size);
+ if (ret || entry_size < sizeof(*hdr) ||
+ entry_size > bufend - buf) {
+ error("malformed xattrs");
+ break;
+ }
+
+ switch (hdr->c_type) {
+ case TYPE_XATTR:
+ do_setxattrs(pathname, buf + sizeof(*hdr),
+ entry_size - sizeof(*hdr));
+ break;
+ default:
+ pr_debug("Unsupported metadata type\n");
+ break;
+ }
+
+ buf += entry_size;
+ }
+
+ return 0;
+}
+
static __initdata struct file *wfile;
static __initdata loff_t wfile_pos;
--
2.51.0
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH v6 3/4] initramfs: read metadata from special file METADATA!!!
2026-11-05 19:37 [PATCH v6 0/4] initramfs: add support for xattrs in the initial ram disk Danny Hu
2026-11-05 19:37 ` [PATCH v6 1/4] ima: skip algorithm availability check until initramfs unpacking is finished Danny Hu
2026-11-05 19:37 ` [PATCH v6 2/4] initramfs: add file metadata Danny Hu
@ 2026-11-05 19:37 ` Danny Hu
2026-11-05 19:37 ` [PATCH v6 4/4] gen_init_cpio: add support for file metadata Danny Hu
3 siblings, 0 replies; 5+ messages in thread
From: Danny Hu @ 2026-11-05 19:37 UTC (permalink / raw)
To: Alexander Viro, Christian Brauner
Cc: Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Eric Snowberg,
Jan Kara, Victor Kamensky, Taras Kondratiuk, Zheng Zengkai,
zhangguangzhi, Danny Hu, Jason Yan, silviu.vlasceanu, hpa, arnd,
james.w.mcmechan, niveditas98, pierre, julien, kbharathi,
alexandr.lobakin, linux-fsdevel, linux-integrity,
linux-security-module, linux-kbuild, initramfs, linux-api,
linux-kernel, bug-cpio
From: Roberto Sassu <roberto.sassu@huawei.com>
Instead of changing the CPIO format, metadata are parsed from regular files
with special name 'METADATA!!!'. This file immediately follows the file
metadata are added to.
This patch checks if the file being extracted has the special name and, if
yes, creates a buffer with the content of that file and transitions
to a new dedicated CollectMetadata state to buffer the metadata contents
in memory without creating a file in the rootfs.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Tianxing Zhang <zhangtianxing3@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: zhoushuiqing <zhoushuiqing2@huawei.com>
Signed-off-by: zhangguangzhi <zhangguangzhi3@huawei.com>
Signed-off-by: Danny Hu <dannyhu@arista.com>
---
v6 changes:
- Introduce a dedicated CollectMetadata state to collect METADATA!!! entries
in memory. This state replaces the metadata flag and eliminates the need to
reset it on failure paths. Since metadata is collected purely in memory, the
entry is no longer extracted as a regular file to the root of the archive.
This also has the benefit of separating metadata collection from do_copy.
- Validate the checksum before setting the xattr with do_parse_metadata
- Improve bookkeeping of previous_name_buf by setting it only after the target
object is created. Clear the buffer on skipped or failed entries to prevent
setting metadata on the wrong target. Indicate that previous_name_buf is
invalid/not set by having the first byte be the NUL character
- Remove "Reviewed-by: Jason Yan <yanaijie@huawei.com>" because patch has
implementation has significantly changed in the v6 revision
v5 changes:
- clean up metadata buffer when returning from unpack_to_rootfs()
init/initramfs.c | 103 +++++++++++++++++++++++++++++++++++++++++------
1 file changed, 90 insertions(+), 13 deletions(-)
diff --git a/init/initramfs.c b/init/initramfs.c
index d206624d1160..a17c26fde5f5 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -34,6 +34,17 @@
static __initdata bool csum_present;
static __initdata u32 io_csum;
+static void __init update_csum(const unsigned char *buf, size_t len)
+{
+ size_t i;
+
+ if (!csum_present)
+ return;
+
+ for (i = 0; i < len; i++)
+ io_csum += buf[i];
+}
+
static ssize_t __init xwrite(struct file *file, const unsigned char *p,
size_t count, loff_t *pos)
{
@@ -50,12 +61,7 @@ static ssize_t __init xwrite(struct file *file, const unsigned char *p,
} else if (rv == 0)
break;
- if (csum_present) {
- ssize_t i;
-
- for (i = 0; i < rv; i++)
- io_csum += p[i];
- }
+ update_csum(p, rv);
p += rv;
out += rv;
@@ -233,6 +239,7 @@ static __initdata enum state {
SkipIt,
GotName,
CopyFile,
+ CollectMetadata,
GotSymlink,
Reset
} state, next_state;
@@ -266,7 +273,7 @@ static void __init read_into(char *buf, unsigned size, enum state next)
}
}
-static __initdata char *header_buf, *symlink_buf, *name_buf;
+static __initdata char *header_buf, *symlink_buf, *name_buf, *previous_name_buf;
static __initdata char *metadata_buf;
static int __init do_start(void)
@@ -308,10 +315,10 @@ static int __init do_header(void)
next_header = (next_header + 3) & ~3;
state = SkipIt;
if (name_len <= 0 || name_len > PATH_MAX)
- return 0;
+ goto skip;
if (S_ISLNK(mode)) {
if (body_len > PATH_MAX)
- return 0;
+ goto skip;
collect = collected = symlink_buf;
remains = N_ALIGN(name_len) + body_len;
next_state = GotSymlink;
@@ -320,6 +327,11 @@ static int __init do_header(void)
}
if (S_ISREG(mode) || !body_len)
read_into(name_buf, N_ALIGN(name_len), GotName);
+ else
+ goto skip;
+ return 0;
+skip:
+ previous_name_buf[0] = '\0';
return 0;
}
@@ -471,6 +483,8 @@ static __initdata loff_t wfile_pos;
static int __init do_name(void)
{
+ bool target_ready = false;
+
state = SkipIt;
next_state = Reset;
@@ -482,6 +496,19 @@ static int __init do_name(void)
return 1;
}
+ if (S_ISREG(mode) && strcmp(collected, METADATA_FILENAME) == 0) {
+ metadata_len = body_len;
+ if (metadata_len)
+ metadata_buf = kmalloc(metadata_len, GFP_KERNEL);
+ else
+ metadata_buf = NULL;
+ io_csum = 0;
+ state = CollectMetadata;
+ return 0;
+ }
+
+ /* Clear metadata target only after checking entry is not metadata */
+ previous_name_buf[0] = '\0';
if (strcmp(collected, "TRAILER!!!") == 0) {
free_hash();
return 0;
@@ -504,24 +531,65 @@ static int __init do_name(void)
if (body_len)
vfs_truncate(&wfile->f_path, body_len);
state = CopyFile;
+ target_ready = true;
}
} else if (S_ISDIR(mode)) {
- init_mkdir(collected, mode);
+ int ret = init_mkdir(collected, mode);
+
+ target_ready = !ret || ret == -EEXIST;
init_chown(collected, uid, gid, 0);
init_chmod(collected, mode);
dir_add(collected, name_len, mtime);
} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
S_ISFIFO(mode) || S_ISSOCK(mode)) {
- if (maybe_link() == 0) {
- init_mknod(collected, mode, rdev);
+ int ml = maybe_link();
+
+ if (ml == 0) {
+ int ret = init_mknod(collected, mode, rdev);
+
+ target_ready = !ret || ret == -EEXIST;
init_chown(collected, uid, gid, 0);
init_chmod(collected, mode);
do_utime(collected, mtime);
+ } else if (ml == 1) {
+ target_ready = true;
}
}
+ if (target_ready)
+ memcpy(previous_name_buf, collected, strlen(collected) + 1);
return 0;
}
+static void __init do_process_metadata(const char *buf, size_t len)
+{
+ /* Still checksum the body if allocation failed. */
+ update_csum((const unsigned char *)buf, len);
+ if (metadata_buf)
+ memcpy(metadata_buf + (metadata_len - body_len), buf, len);
+}
+
+static int __init do_collect_metadata(void)
+{
+ if (byte_count >= body_len) {
+ do_process_metadata(victim, body_len);
+ if (csum_present && io_csum != hdr_csum)
+ error("bad data checksum");
+ else if (metadata_buf && previous_name_buf[0])
+ do_parse_metadata(previous_name_buf);
+ kfree(metadata_buf);
+ metadata_buf = NULL;
+ metadata_len = 0;
+ eat(body_len);
+ state = SkipIt;
+ return 0;
+ }
+
+ do_process_metadata(victim, byte_count);
+ body_len -= byte_count;
+ eat(byte_count);
+ return 1;
+}
+
static int __init do_copy(void)
{
if (byte_count >= body_len) {
@@ -546,6 +614,7 @@ static int __init do_copy(void)
static int __init do_symlink(void)
{
+ previous_name_buf[0] = '\0';
if (collected[name_len - 1] != '\0') {
pr_err("initramfs symlink without nulterm: %.*s\n",
(int)name_len, collected);
@@ -554,7 +623,8 @@ static int __init do_symlink(void)
}
collected[N_ALIGN(name_len) + body_len] = '\0';
clean_path(collected, 0);
- init_symlink(collected + N_ALIGN(name_len), collected);
+ if (!init_symlink(collected + N_ALIGN(name_len), collected))
+ memcpy(previous_name_buf, collected, strlen(collected) + 1);
init_chown(collected, uid, gid, AT_SYMLINK_NOFOLLOW);
do_utime(collected, mtime);
state = SkipIt;
@@ -569,6 +639,7 @@ static __initdata int (*actions[])(void) = {
[SkipIt] = do_skip,
[GotName] = do_name,
[CopyFile] = do_copy,
+ [CollectMetadata] = do_collect_metadata,
[GotSymlink] = do_symlink,
[Reset] = do_reset,
};
@@ -628,6 +699,7 @@ char * __init unpack_to_rootfs(char *buf, unsigned long len)
char header[CPIO_HDRLEN];
char symlink[PATH_MAX + N_ALIGN(PATH_MAX) + 1];
char name[N_ALIGN(PATH_MAX)];
+ char prev_name[PATH_MAX + N_ALIGN(PATH_MAX) + 1];
} *bufs = kmalloc_obj(*bufs);
if (!bufs)
@@ -636,6 +708,8 @@ char * __init unpack_to_rootfs(char *buf, unsigned long len)
header_buf = bufs->header;
symlink_buf = bufs->symlink;
name_buf = bufs->name;
+ previous_name_buf = bufs->prev_name;
+ previous_name_buf[0] = '\0';
state = Start;
this_header = 0;
@@ -678,6 +752,9 @@ char * __init unpack_to_rootfs(char *buf, unsigned long len)
dir_utime();
/* free any hardlink state collected without optional TRAILER!!! */
free_hash();
+ kfree(metadata_buf);
+ metadata_buf = NULL;
+ metadata_len = 0;
kfree(bufs);
return message;
}
--
2.51.0
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH v6 4/4] gen_init_cpio: add support for file metadata
2026-11-05 19:37 [PATCH v6 0/4] initramfs: add support for xattrs in the initial ram disk Danny Hu
` (2 preceding siblings ...)
2026-11-05 19:37 ` [PATCH v6 3/4] initramfs: read metadata from special file METADATA!!! Danny Hu
@ 2026-11-05 19:37 ` Danny Hu
3 siblings, 0 replies; 5+ messages in thread
From: Danny Hu @ 2026-11-05 19:37 UTC (permalink / raw)
To: Alexander Viro, Christian Brauner
Cc: Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Eric Snowberg,
Jan Kara, Victor Kamensky, Taras Kondratiuk, Zheng Zengkai,
zhangguangzhi, Danny Hu, Jason Yan, silviu.vlasceanu, hpa, arnd,
james.w.mcmechan, niveditas98, pierre, julien, kbharathi,
alexandr.lobakin, linux-fsdevel, linux-integrity,
linux-security-module, linux-kbuild, initramfs, linux-api,
linux-kernel, bug-cpio
From: Roberto Sassu <roberto.sassu@huawei.com>
This patch adds support for file metadata (only TYPE_XATTR metadata type).
gen_init_cpio has been modified to read xattrs from files that will be
added to the image and to include file metadata as separate files with the
special name 'METADATA!!!'.
This behavior can be selected by setting the desired file metadata type as
value for CONFIG_INITRAMFS_FILE_METADATA.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Tianxing Zhang <zhangtianxing3@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: zhoushuiqing <zhoushuiqing2@huawei.com>
Signed-off-by: zhangguangzhi <zhangguangzhi3@huawei.com>
Signed-off-by: Danny Hu <dannyhu@arista.com>
---
Changes in v6:
- Detect if path is NULL in write_xattrs and early return
- Define __packed before including initramfs.h in gen_init_cpio.c
Changes in v5:
- context adapt usr/Makefile, usr/gen_initramfs.sh (zhangguangzhi)
- del duplicate code in usr/Makefile (zhangguangzhi)
- fix checkpatch warning STATIC_CONST_CHAR_ARRAY in usr/gen_init_cpio.c:38
(zhangguangzhi)
- make CONFIG_INITRAMFS_FILE_METADATA a choice rather than having to
specify it manually
- document -e option and supported values in gen_init_cpio usage()
- Update gen_initramfs.sh to pass source paths to gen_init_cpio.c for
nonregular entries (slink, dir, nod). Modify gen_init_cpio to
properly collect xattrs from the source object. Without this change,
xattrs will not get included for slink, dir and nod.
- xattr collection now uses llistxattr() and lgetxattr() so symlink
xattrs come from the link itself rather than the target.
- use the size_t hexadecimal format specifier in write_xattrs()
- initialize xattr_value as NULL to prevent free of uninitialized ptr
- free xattr_list after checking whether xattr iteration completed
- clean up temporary metadata file before gen_init_cpio exits
usr/Kconfig | 19 ++++
usr/Makefile | 3 +-
usr/gen_init_cpio.c | 221 +++++++++++++++++++++++++++++++++++++------
usr/gen_initramfs.sh | 15 ++-
4 files changed, 224 insertions(+), 34 deletions(-)
diff --git a/usr/Kconfig b/usr/Kconfig
index 9279a2893ab0..135a9248bba2 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -227,3 +227,22 @@ config INITRAMFS_COMPRESSION_NONE
filesystem image will be present in memory simultaneously
endchoice
+
+choice
+ prompt "File metadata type"
+ default INITRAMFS_FILE_METADATA_NONE
+ help
+ Specify the metadata types to be included in the image.
+
+ If you are not sure, leave unchanged.
+
+ config INITRAMFS_FILE_METADATA_NONE
+ bool "no xattrs (default)"
+ config INITRAMFS_FILE_METADATA_XATTR
+ bool "xattr"
+endchoice
+
+config INITRAMFS_FILE_METADATA
+ string
+ default "" if INITRAMFS_FILE_METADATA_NONE
+ default "xattr" if INITRAMFS_FILE_METADATA_XATTR
diff --git a/usr/Makefile b/usr/Makefile
index e8f42478a0b7..dc4a1f4b3da2 100644
--- a/usr/Makefile
+++ b/usr/Makefile
@@ -65,7 +65,8 @@ quiet_cmd_initfs = GEN $@
$(addprefix -u , $(CONFIG_INITRAMFS_ROOT_UID)) \
$(addprefix -g , $(CONFIG_INITRAMFS_ROOT_GID)) \
$(if $(KBUILD_BUILD_TIMESTAMP), -d "$(KBUILD_BUILD_TIMESTAMP)") \
- $(ramfs-input)
+ $(if $(filter-out "",$(CONFIG_INITRAMFS_FILE_METADATA)), \
+ -e $(CONFIG_INITRAMFS_FILE_METADATA)) $(ramfs-input)
# We rebuild initramfs_data.cpio if:
# 1) Any included file is newer than initramfs_data.cpio
diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c
index b7296edc6626..64ac78e68087 100644
--- a/usr/gen_init_cpio.c
+++ b/usr/gen_init_cpio.c
@@ -6,6 +6,7 @@
#include <stdbool.h>
#include <sys/types.h>
#include <sys/stat.h>
+#include <sys/xattr.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
@@ -14,6 +15,12 @@
#include <ctype.h>
#include <limits.h>
+#ifndef __packed
+#define __packed __attribute__((__packed__))
+#endif
+
+#include "../include/linux/initramfs.h"
+
/*
* Original work by Jeff Garzik
*
@@ -37,12 +44,126 @@ static bool do_file_mtime;
static bool do_csum = false;
static int outfd = STDOUT_FILENO;
static unsigned int dalign;
+static char metadata_path[] = "/tmp/cpio-metadata-XXXXXX";
+static int metadata_fd = -1;
struct file_handler {
const char *type;
int (*handler)(const char *line);
};
+static enum metadata_types parse_metadata_type(char *arg)
+{
+ static char *metadata_type_str[TYPE__LAST] = {
+ [TYPE_NONE] = "none",
+ [TYPE_XATTR] = "xattr",
+ };
+ int i;
+
+ for (i = 0; i < TYPE__LAST; i++)
+ if (!strcmp(metadata_type_str[i], arg))
+ return i;
+
+ return TYPE_NONE;
+}
+
+static int cpio_mkfile(const char *name, const char *location,
+ unsigned int mode, uid_t uid, gid_t gid,
+ unsigned int nlinks);
+
+static char *cpio_replace_env(char *new_location);
+
+static int write_xattrs(const char *path)
+{
+ struct metadata_hdr hdr = { .c_version = 1, .c_type = TYPE_XATTR };
+ char str[sizeof(hdr.c_size) + 1];
+ char *xattr_list, *list_ptr;
+ char *xattr_value = NULL;
+ ssize_t list_len, name_len, value_len, len;
+ int ret = -EINVAL;
+
+ if (metadata_fd < 0 || !path)
+ return 0;
+
+ if (path == metadata_path)
+ return 0;
+
+ list_len = llistxattr(path, NULL, 0);
+ if (list_len <= 0)
+ return 0;
+
+ list_ptr = xattr_list = malloc(list_len);
+ if (!list_ptr) {
+ fprintf(stderr, "out of memory\n");
+ return ret;
+ }
+
+ len = llistxattr(path, xattr_list, list_len);
+ if (len != list_len)
+ goto out;
+
+ if (ftruncate(metadata_fd, 0))
+ goto out;
+
+ lseek(metadata_fd, 0, SEEK_SET);
+
+ while (list_ptr < xattr_list + list_len) {
+ name_len = strlen(list_ptr);
+
+ value_len = lgetxattr(path, list_ptr, NULL, 0);
+ if (value_len < 0) {
+ fprintf(stderr, "cannot get xattrs\n");
+ break;
+ }
+
+ if (value_len) {
+ xattr_value = malloc(value_len);
+ if (!xattr_value) {
+ fprintf(stderr, "out of memory\n");
+ break;
+ }
+ } else {
+ xattr_value = NULL;
+ }
+
+ len = lgetxattr(path, list_ptr, xattr_value, value_len);
+ if (len != value_len)
+ break;
+
+ snprintf(str, sizeof(str), "%.8zx",
+ sizeof(hdr) + name_len + 1 + value_len);
+
+ memcpy(hdr.c_size, str, sizeof(hdr.c_size));
+
+ if (write(metadata_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
+ break;
+
+ if (write(metadata_fd, list_ptr, name_len + 1) != name_len + 1)
+ break;
+
+ if (write(metadata_fd, xattr_value, value_len) != value_len)
+ break;
+
+ if (fsync(metadata_fd))
+ break;
+
+ list_ptr += name_len + 1;
+ free(xattr_value);
+ xattr_value = NULL;
+ }
+
+ free(xattr_value);
+out:
+ if (list_ptr != xattr_list + list_len) {
+ free(xattr_list);
+ return ret;
+ }
+
+ free(xattr_list);
+
+ return cpio_mkfile(METADATA_FILENAME, metadata_path, S_IFREG, 0, 0, 1);
+}
+
static int push_buf(const char *name, size_t name_len)
{
ssize_t len;
@@ -119,7 +240,8 @@ static int cpio_trailer(void)
}
static int cpio_mkslink(const char *name, const char *target,
- unsigned int mode, uid_t uid, gid_t gid)
+ const char *location, unsigned int mode,
+ uid_t uid, gid_t gid)
{
int len;
unsigned int namesize, targetsize = strlen(target) + 1;
@@ -150,7 +272,8 @@ static int cpio_mkslink(const char *name, const char *target,
push_buf(name, namesize) < 0 ||
push_pad(padlen(offset, 4)) < 0 ||
push_buf(target, targetsize) < 0 ||
- push_pad(padlen(offset, 4)) < 0)
+ push_pad(padlen(offset, 4)) < 0 ||
+ write_xattrs(location) < 0)
return -1;
return 0;
@@ -161,22 +284,29 @@ static int cpio_mkslink_line(const char *line)
{
char name[PATH_MAX + 1];
char target[PATH_MAX + 1];
+ char location[PATH_MAX + 1];
unsigned int mode;
int uid;
int gid;
+ int nfields;
int rc = -1;
- if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, target, &mode, &uid, &gid)) {
- fprintf(stderr, "Unrecognized dir format '%s'", line);
+ nfields = sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX)
+ "s %o %d %d %" str(PATH_MAX) "s",
+ name, target, &mode, &uid, &gid, location);
+ if (nfields < 5) {
+ fprintf(stderr, "Unrecognized slink format '%s'", line);
goto fail;
}
- rc = cpio_mkslink(name, target, mode, uid, gid);
+ rc = cpio_mkslink(name, target,
+ nfields == 6 ? cpio_replace_env(location) : NULL,
+ mode, uid, gid);
fail:
return rc;
}
-static int cpio_mkgeneric(const char *name, unsigned int mode,
- uid_t uid, gid_t gid)
+static int cpio_mkgeneric(const char *name, const char *location,
+ unsigned int mode, uid_t uid, gid_t gid)
{
int len;
unsigned int namesize;
@@ -204,7 +334,8 @@ static int cpio_mkgeneric(const char *name, unsigned int mode,
offset += len;
if (len != CPIO_HDR_LEN ||
- push_rest(name, namesize) < 0)
+ push_rest(name, namesize) < 0 ||
+ write_xattrs(location) < 0)
return -1;
return 0;
@@ -239,18 +370,24 @@ static const struct generic_type generic_type_table[] = {
static int cpio_mkgeneric_line(const char *line, enum generic_types gt)
{
char name[PATH_MAX + 1];
+ char location[PATH_MAX + 1];
unsigned int mode;
int uid;
int gid;
+ int nfields;
int rc = -1;
- if (4 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d", name, &mode, &uid, &gid)) {
+ nfields = sscanf(line, "%" str(PATH_MAX) "s %o %d %d %"
+ str(PATH_MAX) "s", name, &mode, &uid, &gid, location);
+ if (nfields < 4) {
fprintf(stderr, "Unrecognized %s format '%s'",
- line, generic_type_table[gt].type);
+ generic_type_table[gt].type, line);
goto fail;
}
mode |= generic_type_table[gt].mode;
- rc = cpio_mkgeneric(name, mode, uid, gid);
+ rc = cpio_mkgeneric(name,
+ nfields == 5 ? cpio_replace_env(location) : NULL,
+ mode, uid, gid);
fail:
return rc;
}
@@ -270,9 +407,9 @@ static int cpio_mksock_line(const char *line)
return cpio_mkgeneric_line(line, GT_SOCK);
}
-static int cpio_mknod(const char *name, unsigned int mode,
- uid_t uid, gid_t gid, char dev_type,
- unsigned int maj, unsigned int min)
+static int cpio_mknod(const char *name, const char *location,
+ unsigned int mode, uid_t uid, gid_t gid, char dev_type,
+ unsigned int maj, unsigned int min)
{
int len;
unsigned int namesize;
@@ -305,7 +442,8 @@ static int cpio_mknod(const char *name, unsigned int mode,
offset += len;
if (len != CPIO_HDR_LEN ||
- push_rest(name, namesize) < 0)
+ push_rest(name, namesize) < 0 ||
+ write_xattrs(location) < 0)
return -1;
return 0;
@@ -314,20 +452,26 @@ static int cpio_mknod(const char *name, unsigned int mode,
static int cpio_mknod_line(const char *line)
{
char name[PATH_MAX + 1];
+ char location[PATH_MAX + 1];
unsigned int mode;
int uid;
int gid;
char dev_type;
unsigned int maj;
unsigned int min;
+ int nfields;
int rc = -1;
- if (7 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d %c %u %u",
- name, &mode, &uid, &gid, &dev_type, &maj, &min)) {
+ nfields = sscanf(line, "%" str(PATH_MAX) "s %o %d %d %c %u %u %"
+ str(PATH_MAX) "s", name, &mode, &uid, &gid, &dev_type,
+ &maj, &min, location);
+ if (nfields < 7) {
fprintf(stderr, "Unrecognized nod format '%s'", line);
goto fail;
}
- rc = cpio_mknod(name, mode, uid, gid, dev_type, maj, min);
+ rc = cpio_mknod(name,
+ nfields == 8 ? cpio_replace_env(location) : NULL,
+ mode, uid, gid, dev_type, maj, min);
fail:
return rc;
}
@@ -490,7 +634,7 @@ static int cpio_mkfile(const char *name, const char *location,
name += namesize;
}
ino++;
- rc = 0;
+ rc = write_xattrs(location);
error:
if (file >= 0)
@@ -570,22 +714,24 @@ static int cpio_mkfile_line(const char *line)
static void usage(const char *prog)
{
fprintf(stderr, "Usage:\n"
- "\t%s [-t <timestamp>] [-c] [-o <output_file>] [-a <data_align>] <cpio_list>\n"
+ "\t%s [-t <timestamp>] [-c] [-o <output_file>] [-a <data_align>] [-e <type>] <cpio_list>\n"
"\n"
"<cpio_list> is a file containing newline separated entries that\n"
"describe the files to be included in the initramfs archive:\n"
"\n"
"# a comment\n"
"file <name> <location> <mode> <uid> <gid> [<hard links>]\n"
- "dir <name> <mode> <uid> <gid>\n"
- "nod <name> <mode> <uid> <gid> <dev_type> <maj> <min>\n"
- "slink <name> <target> <mode> <uid> <gid>\n"
- "pipe <name> <mode> <uid> <gid>\n"
- "sock <name> <mode> <uid> <gid>\n"
+ "dir <name> <mode> <uid> <gid> [<location>]\n"
+ "nod <name> <mode> <uid> <gid> <dev_type> <maj> <min> [<location>]\n"
+ "slink <name> <target> <mode> <uid> <gid> [<location>]\n"
+ "pipe <name> <mode> <uid> <gid> [<location>]\n"
+ "sock <name> <mode> <uid> <gid> [<location>]\n"
"\n"
"<name> name of the file/dir/nod/etc in the archive\n"
"<location> location of the file in the current filesystem\n"
" expands shell variables quoted with ${}\n"
+ " optional for nonregular entries; used to read xattrs\n"
+ " with -e xattr. If omitted, no xattrs are included.\n"
"<target> link target\n"
"<mode> mode/permissions of the file\n"
"<uid> user id (0=root)\n"
@@ -611,7 +757,8 @@ static void usage(const char *prog)
"<output_file>: write cpio to this file instead of stdout\n"
"<data_align>: attempt to align file data by zero-padding the\n"
"filename field up to data_align. Must be a multiple of 4.\n"
- "Alignment is best-effort; PATH_MAX limits filename padding.\n",
+ "Alignment is best-effort; PATH_MAX limits filename padding.\n"
+ "<type>: include file metadata: none (default) or xattr.\n",
prog);
}
@@ -640,7 +787,7 @@ static const struct file_handler file_handler_table[] = {
}
};
-#define LINE_SIZE (2 * PATH_MAX + 50)
+#define LINE_SIZE (3 * PATH_MAX + 50)
int main (int argc, char *argv[])
{
@@ -650,10 +797,11 @@ int main (int argc, char *argv[])
int ec = 0;
int line_nr = 0;
const char *filename;
+ enum metadata_types metadata_type = TYPE_NONE;
default_mtime = time(NULL);
while (1) {
- int opt = getopt(argc, argv, "t:cho:a:");
+ int opt = getopt(argc, argv, "t:e:cho:a:");
char *invalid;
if (opt == -1)
@@ -669,6 +817,9 @@ int main (int argc, char *argv[])
}
do_file_mtime = true;
break;
+ case 'e':
+ metadata_type = parse_metadata_type(optarg);
+ break;
case 'c':
do_csum = true;
break;
@@ -721,6 +872,13 @@ int main (int argc, char *argv[])
usage(argv[0]);
exit(1);
}
+ if (metadata_type != TYPE_NONE) {
+ metadata_fd = mkstemp(metadata_path);
+ if (metadata_fd < 0) {
+ fprintf(stderr, "cannot create temporary file\n");
+ exit(1);
+ }
+ }
while (fgets(line, LINE_SIZE, cpio_list)) {
int type_idx;
@@ -777,5 +935,12 @@ int main (int argc, char *argv[])
if (ec == 0)
ec = cpio_trailer();
+ if (metadata_type != TYPE_NONE) {
+ close(metadata_fd);
+ if (unlink(metadata_path))
+ fprintf(stderr,
+ "warning: cannot remove temporary file %s: %s\n",
+ metadata_path, strerror(errno));
+ }
exit(ec);
}
diff --git a/usr/gen_initramfs.sh b/usr/gen_initramfs.sh
index 7eba2fddf0ef..fea88d761d62 100755
--- a/usr/gen_initramfs.sh
+++ b/usr/gen_initramfs.sh
@@ -14,7 +14,7 @@ set -e
usage() {
cat << EOF
Usage:
-$0 [-o <file>] [-l <dep_list>] [-u <uid>] [-g <gid>] {-d | <cpio_source>} ...
+$0 [-o <file>] [-l <dep_list>] [-u <uid>] [-g <gid>] {-d | <cpio_source>} [-e <type>]...
-o <file> Create initramfs file named <file> by using gen_init_cpio
-l <dep_list> Create dependency list named <dep_list>
-u <uid> User ID to map to user ID 0 (root).
@@ -27,6 +27,7 @@ $0 [-o <file>] [-l <dep_list>] [-u <uid>] [-g <gid>] {-d | <cpio_source>} ...
<cpio_source> File list or directory for cpio archive.
If <cpio_source> is a .cpio file it will be used
as direct input to initramfs.
+ -e <type> File metadata type to include in the cpio archive.
All options except -o and -l may be repeated and are interpreted
sequentially and immediately. -u and -g states are preserved across
@@ -113,14 +114,14 @@ parse() {
[ -b "${location}" ] && dev="b" || dev="c"
- str="${ftype} ${name} ${str} ${dev} ${maj} ${min}"
+ str="${ftype} ${name} ${str} ${dev} ${maj} ${min} ${location}"
;;
"slink")
local target=`readlink "${location}"`
- str="${ftype} ${name} ${target} ${str}"
+ str="${ftype} ${name} ${target} ${str} ${location}"
;;
*)
- str="${ftype} ${name} ${str}"
+ str="${ftype} ${name} ${str} ${location}"
;;
esac
@@ -228,6 +229,10 @@ while [ $# -gt 0 ]; do
fi
shift
;;
+ "-e") # file metadata type
+ metadata_arg="-e $1"
+ shift
+ ;;
"-h")
usage
exit 0
@@ -247,4 +252,4 @@ done
# If output_file is set we will generate cpio archive
# we are careful to delete tmp files
-usr/gen_init_cpio $output $timestamp $cpio_list
+usr/gen_init_cpio $output $metadata_arg $timestamp $cpio_list
--
2.51.0
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