[packages/kmod] don't use in-kernel xz module decompression with kernels < 6.6

[atler]

commit 1942c4020a1b9043bdf8e70b7352fbfbdef57c9b
Author: Jan Palus <atler at pld-linux.org>
Date:   Fri May 2 20:24:27 2025 +0200

    don't use in-kernel xz module decompression with kernels < 6.6
    
    kmod >= 31 passes compressed module to kernel if in-kernel module
    decompression is supported. kernel's "xz embedded" decompressor supports
    crc32 checksum algorithm but not xz's default crc64:
    
    https://www.kernel.org/doc/html/v6.14/staging/xz.html
    
    until kernel 6.6 modules were installed with crc64 therefore
    incompatible with itself. following commit fixes the issue starting with
    kernel 6.6:
    
    https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fbf5892df21a8ccfcb2fda0fd65bc3169c89ed28
    
    resolve the issue by checking kernel version first and avoid using
    in-kernel xz decompressor if it's lower than 6.6

 kmod.spec                         |  2 ++
 xz-in-kernel-decompr-compat.patch | 45 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+)
---
diff --git a/kmod.spec b/kmod.spec
index 5fc7e00..5c6336e 100644
--- a/kmod.spec
+++ b/kmod.spec
@@ -23,6 +23,7 @@ Source1:	%{name}-blacklist
 Source2:	%{name}-usb
 Patch0:		%{name}-modprobe.d-kver.patch
 Patch1:		%{name}-depmod.d-kver.patch
+Patch2:		xz-in-kernel-decompr-compat.patch
 URL:		https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git
 BuildRequires:	autoconf >= 2.64
 BuildRequires:	automake >= 1:1.11
@@ -123,6 +124,7 @@ Bashowe uzupełnianie nazw dla narzędzi kmod.
 %setup -q
 %patch -P 0 -p1
 %patch -P 1 -p1
+%patch -P 2 -p1
 
 %build
 %{__libtoolize}
diff --git a/xz-in-kernel-decompr-compat.patch b/xz-in-kernel-decompr-compat.patch
new file mode 100644
index 0000000..d37318c
--- /dev/null
+++ b/xz-in-kernel-decompr-compat.patch
@@ -0,0 +1,45 @@
+--- kmod-34.2/libkmod/libkmod.c.orig	2025-05-02 14:53:30.252042909 +0200
++++ kmod-34.2/libkmod/libkmod.c	2025-05-02 20:20:41.040692282 +0200
+@@ -206,9 +206,39 @@
+ 
+ 	if (streq(buf, "zstd\n"))
+ 		return KMOD_FILE_COMPRESSION_ZSTD;
+-	else if (streq(buf, "xz\n"))
+-		return KMOD_FILE_COMPRESSION_XZ;
+-	else if (streq(buf, "gzip\n"))
++	else if (streq(buf, "xz\n")) {
++		struct utsname u;
++		long major, minor;
++		char *num, *endptr;
++
++		if (uname(&u) < 0)
++			return KMOD_FILE_COMPRESSION_NONE;
++
++		num = strtok(u.release, ".");
++
++		if (num == NULL)
++			return KMOD_FILE_COMPRESSION_NONE;
++
++		major = strtol(num, &endptr, 10);
++
++		if (*endptr != '\0')
++			return KMOD_FILE_COMPRESSION_NONE;
++
++		num = strtok(NULL, ".");
++
++		if (num == NULL)
++			return KMOD_FILE_COMPRESSION_NONE;
++
++		minor = strtol(num, &endptr, 10);
++
++		if (*endptr != '\0')
++			return KMOD_FILE_COMPRESSION_NONE;
++
++		if (major > 6L || (major == 6L && minor >= 6L))
++			return KMOD_FILE_COMPRESSION_XZ;
++		else
++			return KMOD_FILE_COMPRESSION_NONE;
++	} else if (streq(buf, "gzip\n"))
+ 		return KMOD_FILE_COMPRESSION_ZLIB;
+ 
+ 	ERR(ctx, "unknown kernel compression %s", buf);
================================================================

---- gitweb:

http://git.pld-linux.org/gitweb.cgi/packages/kmod.git/commitdiff/1942c4020a1b9043bdf8e70b7352fbfbdef57c9b