From: Roberto Sassu roberto.sassu@huawei.com
euleros inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I7QZ2M CVE: NA
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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 calls do_parse_metadata() to parse metadata from the buffer.
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 Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: zhoushuiqing zhoushuiqing2@huawei.com --- init/initramfs.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 49 insertions(+), 1 deletion(-)
diff --git a/init/initramfs.c b/init/initramfs.c index 3b272c56a987..0311acda2209 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -253,6 +253,7 @@ static void __init read_into(char *buf, unsigned size, enum state next) }
static __initdata char *header_buf, *symlink_buf, *name_buf, *metadata_buf; +static __initdata char *metadata_buf_ptr, *previous_name_buf;
static int __init do_start(void) { @@ -437,6 +438,7 @@ static int __init __maybe_unused do_parse_metadata(char *pathname)
static __initdata struct file *wfile; static __initdata loff_t wfile_pos; +static int metadata __initdata;
static int __init do_name(void) { @@ -445,6 +447,10 @@ static int __init do_name(void) if (strcmp(collected, "TRAILER!!!") == 0) { free_hash(); return 0; + } else if (strcmp(collected, METADATA_FILENAME) == 0) { + metadata = 1; + } else { + memcpy(previous_name_buf, collected, strlen(collected) + 1); } clean_path(collected, mode); if (S_ISREG(mode)) { @@ -482,11 +488,47 @@ static int __init do_name(void) return 0; }
+static int __init do_process_metadata(char *buf, int len, bool last) +{ + int ret = 0; + + if (!metadata_buf) { + metadata_buf_ptr = metadata_buf = kmalloc(body_len, GFP_KERNEL); + if (!metadata_buf_ptr) { + ret = -ENOMEM; + goto out; + } + + metadata_len = body_len; + } + + if (metadata_buf_ptr + len > metadata_buf + metadata_len) { + ret = -EINVAL; + goto out; + } + + memcpy(metadata_buf_ptr, buf, len); + metadata_buf_ptr += len; + + if (last) + do_parse_metadata(previous_name_buf); +out: + if (ret < 0 || last) { + kfree(metadata_buf); + metadata_buf = NULL; + metadata = 0; + } + + return ret; +} + static int __init do_copy(void) { if (byte_count >= body_len) { if (xwrite(wfile, victim, body_len, &wfile_pos) != body_len) error("write error"); + if (metadata) + do_process_metadata(victim, body_len, true);
do_utime_path(&wfile->f_path, mtime); fput(wfile); @@ -498,6 +540,8 @@ static int __init do_copy(void) } else { if (xwrite(wfile, victim, byte_count, &wfile_pos) != byte_count) error("write error"); + if (metadata) + do_process_metadata(victim, byte_count, false); body_len -= byte_count; eat(byte_count); return 1; @@ -507,6 +551,7 @@ static int __init do_copy(void) static int __init do_symlink(void) { collected[N_ALIGN(name_len) + body_len] = '\0'; + memcpy(previous_name_buf, collected, strlen(collected) + 1); clean_path(collected, 0); init_symlink(collected + N_ALIGN(name_len), collected); init_chown(collected, uid, gid, AT_SYMLINK_NOFOLLOW); @@ -574,8 +619,10 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len) header_buf = kmalloc(110, GFP_KERNEL); symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL); name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL); + previous_name_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, + GFP_KERNEL);
- if (!header_buf || !symlink_buf || !name_buf) + if (!header_buf || !symlink_buf || !name_buf || !previous_name_buf) panic_show_mem("can't allocate buffers");
state = Start; @@ -620,6 +667,7 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len) len -= my_inptr; } dir_utime(); + kfree(previous_name_buf); kfree(name_buf); kfree(symlink_buf); kfree(header_buf);