On Mon, Feb 12, 2024 at 05:23:09PM GMT, Emil Velikov via B4 Relay wrote:
From: Emil Velikov <emil.l.velikov@xxxxxxxxx>
Currently, when built w/o given compression we'll incorrectly report a
"compression_none".
As we reach do_finit_module(), we'll naively assume that the kernel can
handle the compressed module, yet omit the MODULE_INIT_COMPRESSED_FILE
flag.
As result the kernel will barf at us, do_finit_module will fail with non
-ENOSYS and we won't end in the do_init_module codepath (which will also
fail).
In other words: with this change, you can build kmod without zstd, xz
and zlib support and the kernel will load the modules, assuming it
supports the format \o/
Signed-off-by: Emil Velikov <emil.l.velikov@xxxxxxxxx>
nice.
Reviewed-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Lucas De Marchi
---
libkmod/libkmod-file.c | 27 ++++++++++++++++++---------
1 file changed, 18 insertions(+), 9 deletions(-)
diff --git a/libkmod/libkmod-file.c b/libkmod/libkmod-file.c
index 3a79464..b69f1ef 100644
--- a/libkmod/libkmod-file.c
+++ b/libkmod/libkmod-file.c
@@ -174,9 +174,14 @@ out:
free((void *)zst_outb.dst);
return ret;
}
+#else
+static int load_zstd(struct kmod_file *file)
+{
+ return -ENOSYS;
+}
+#endif
static const char magic_zstd[] = {0x28, 0xB5, 0x2F, 0xFD};
-#endif
#ifdef ENABLE_XZ
static void xz_uncompress_belch(struct kmod_file *file, lzma_ret ret)
@@ -275,9 +280,14 @@ static int load_xz(struct kmod_file *file)
lzma_end(&strm);
return ret;
}
+#else
+static int load_xz(struct kmod_file *file)
+{
+ return -ENOSYS;
+}
+#endif
static const char magic_xz[] = {0xfd, '7', 'z', 'X', 'Z', 0};
-#endif
#ifdef ENABLE_ZLIB
#define READ_STEP (4 * 1024 * 1024)
@@ -339,9 +349,14 @@ error:
gzclose(gzf); /* closes the gzfd */
return err;
}
+#else
+static int load_zlib(struct kmod_file *file)
+{
+ return -ENOSYS;
+}
+#endif
static const char magic_zlib[] = {0x1f, 0x8b};
-#endif
static const struct comp_type {
size_t magic_size;
@@ -349,15 +364,9 @@ static const struct comp_type {
const char *magic_bytes;
int (*load)(struct kmod_file *file);
} comp_types[] = {
-#ifdef ENABLE_ZSTD
{sizeof(magic_zstd), KMOD_FILE_COMPRESSION_ZSTD, magic_zstd, load_zstd},
-#endif
-#ifdef ENABLE_XZ
{sizeof(magic_xz), KMOD_FILE_COMPRESSION_XZ, magic_xz, load_xz},
-#endif
-#ifdef ENABLE_ZLIB
{sizeof(magic_zlib), KMOD_FILE_COMPRESSION_ZLIB, magic_zlib, load_zlib},
-#endif
{0, KMOD_FILE_COMPRESSION_NONE, NULL, NULL}
};
--
2.43.0
