From: Justin Covell <jujugoboom-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: devicetree-compiler-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: Justin Covell <jujugoboom-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: [PATCHv2] Set last_comp_version correctly in new dtb and fix potential version issues in fdt_open_into
Date: Mon, 28 Dec 2020 15:42:43 -0800 [thread overview]
Message-ID: <20201228234243.5058-1-jujugoboom@gmail.com> (raw)
Hi,
I've added checks to fdt_open_into to validate the version before reading into buffer, as well as maintaining the accurate
version information of the fdt when loaded into the buffer. Hopefully this would help stop any issues with reading a
fdt with a lower than compatible verison into a buffer and it being misrepresented as a current version.
Signed-off-by: Justin Covell <jujugoboom-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
libfdt/fdt_rw.c | 10 ++++++----
libfdt/fdt_sw.c | 2 +-
libfdt/libfdt.h | 1 +
3 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/libfdt/fdt_rw.c b/libfdt/fdt_rw.c
index 68887b9..feab26c 100644
--- a/libfdt/fdt_rw.c
+++ b/libfdt/fdt_rw.c
@@ -428,12 +428,14 @@ int fdt_open_into(const void *fdt, void *buf, int bufsize)
if (can_assume(LATEST) || fdt_version(fdt) >= 17) {
struct_size = fdt_size_dt_struct(fdt);
- } else {
+ } else if (fdt_version(fdt) == 16) {
struct_size = 0;
while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)
;
if (struct_size < 0)
return struct_size;
+ } else {
+ return -FDT_ERR_BADVERSION;
}
if (can_assume(LIBFDT_ORDER) ||
@@ -442,7 +444,7 @@ int fdt_open_into(const void *fdt, void *buf, int bufsize)
err = fdt_move(fdt, buf, bufsize);
if (err)
return err;
- fdt_set_version(buf, 17);
+ fdt_set_version(buf, fdt_version(fdt));
fdt_set_size_dt_struct(buf, struct_size);
fdt_set_totalsize(buf, bufsize);
return 0;
@@ -470,8 +472,8 @@ int fdt_open_into(const void *fdt, void *buf, int bufsize)
fdt_set_magic(buf, FDT_MAGIC);
fdt_set_totalsize(buf, bufsize);
- fdt_set_version(buf, 17);
- fdt_set_last_comp_version(buf, 16);
+ fdt_set_version(buf, fdt_version(fdt));
+ fdt_set_last_comp_version(buf, fdt_last_comp_version(fdt));
fdt_set_boot_cpuid_phys(buf, fdt_boot_cpuid_phys(fdt));
return 0;
diff --git a/libfdt/fdt_sw.c b/libfdt/fdt_sw.c
index 68b543c..4c569ee 100644
--- a/libfdt/fdt_sw.c
+++ b/libfdt/fdt_sw.c
@@ -377,7 +377,7 @@ int fdt_finish(void *fdt)
fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt));
/* And fix up fields that were keeping intermediate state. */
- fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION);
+ fdt_set_last_comp_version(fdt, FDT_LAST_COMPATIBLE_VERSION);
fdt_set_magic(fdt, FDT_MAGIC);
return 0;
diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h
index 2bc16a8..73467f7 100644
--- a/libfdt/libfdt.h
+++ b/libfdt/libfdt.h
@@ -14,6 +14,7 @@ extern "C" {
#endif
#define FDT_FIRST_SUPPORTED_VERSION 0x02
+#define FDT_LAST_COMPATIBLE_VERSION 0x10
#define FDT_LAST_SUPPORTED_VERSION 0x11
/* Error codes: informative error codes */
--
2.25.1
next reply other threads:[~2020-12-28 23:42 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-28 23:42 Justin Covell [this message]
[not found] ` <20201228234243.5058-1-jujugoboom-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2020-12-29 0:42 ` [PATCHv2] Set last_comp_version correctly in new dtb and fix potential version issues in fdt_open_into David Gibson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201228234243.5058-1-jujugoboom@gmail.com \
--to=jujugoboom-re5jqeeqqe8avxtiumwx3w@public.gmane.org \
--cc=devicetree-compiler-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).