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authorLinus Torvalds <torvalds@linux-foundation.org>2022-12-13 14:05:39 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2022-12-13 14:05:39 -0800
commit3ba2c3ff98ea8bfb219288dbacf2a23a902c751b (patch)
tree90165b304a5b0cf50bc88883ca7a61f1cec65b8c /kernel/module/decompress.c
parent0015edd6f66172f93aa720192020138ca13ba0a6 (diff)
parent4f1354d5c6a3264c91238962d1597eef40c40419 (diff)
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Merge tag 'modules-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull modules updates from Luis Chamberlain: "Tux gets for xmas an improvement to the average lookup performance of kallsyms_lookup_name() by 715x thanks to the work by Zhen Lei, which upgraded our old implementation from being O(n) to O(log(n)), while also retaining the old implementation support on /proc/kallsyms. The only penalty was increasing the memory footprint by 3 * kallsyms_num_syms. Folks who want to improve this further now also have a dedicated selftest facility through KALLSYMS_SELFTEST. Stephen Boyd added zstd in-kernel decompression support, but the only users of this would be folks using the load-pin LSM because otherwise we do module decompression in userspace. The only other thing with mentioning is a minor boot time optimization by Rasmus Villemoes which deferes param_sysfs_init() to late init. The rest is cleanups and minor fixes" * tag 'modules-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: livepatch: Call klp_match_callback() in klp_find_callback() to avoid code duplication module/decompress: Support zstd in-kernel decompression kallsyms: Remove unneeded semicolon kallsyms: Add self-test facility livepatch: Use kallsyms_on_each_match_symbol() to improve performance kallsyms: Add helper kallsyms_on_each_match_symbol() kallsyms: Reduce the memory occupied by kallsyms_seqs_of_names[] kallsyms: Correctly sequence symbols when CONFIG_LTO_CLANG=y kallsyms: Improve the performance of kallsyms_lookup_name() scripts/kallsyms: rename build_initial_tok_table() module: Fix NULL vs IS_ERR checking for module_get_next_page kernel/params.c: defer most of param_sysfs_init() to late_initcall time module: Remove unused macros module_addr_min/max module: remove redundant module_sysfs_initialized variable
Diffstat (limited to 'kernel/module/decompress.c')
-rw-r--r--kernel/module/decompress.c100
1 files changed, 94 insertions, 6 deletions
diff --git a/kernel/module/decompress.c b/kernel/module/decompress.c
index c033572d83f0..bb79ac1a6d8f 100644
--- a/kernel/module/decompress.c
+++ b/kernel/module/decompress.c
@@ -50,7 +50,7 @@ static struct page *module_get_next_page(struct load_info *info)
return page;
}
-#ifdef CONFIG_MODULE_COMPRESS_GZIP
+#if defined(CONFIG_MODULE_COMPRESS_GZIP)
#include <linux/zlib.h>
#define MODULE_COMPRESSION gzip
#define MODULE_DECOMPRESS_FN module_gzip_decompress
@@ -114,8 +114,8 @@ static ssize_t module_gzip_decompress(struct load_info *info,
do {
struct page *page = module_get_next_page(info);
- if (!page) {
- retval = -ENOMEM;
+ if (IS_ERR(page)) {
+ retval = PTR_ERR(page);
goto out_inflate_end;
}
@@ -141,7 +141,7 @@ out:
kfree(s.workspace);
return retval;
}
-#elif CONFIG_MODULE_COMPRESS_XZ
+#elif defined(CONFIG_MODULE_COMPRESS_XZ)
#include <linux/xz.h>
#define MODULE_COMPRESSION xz
#define MODULE_DECOMPRESS_FN module_xz_decompress
@@ -173,8 +173,8 @@ static ssize_t module_xz_decompress(struct load_info *info,
do {
struct page *page = module_get_next_page(info);
- if (!page) {
- retval = -ENOMEM;
+ if (IS_ERR(page)) {
+ retval = PTR_ERR(page);
goto out;
}
@@ -199,6 +199,94 @@ static ssize_t module_xz_decompress(struct load_info *info,
xz_dec_end(xz_dec);
return retval;
}
+#elif defined(CONFIG_MODULE_COMPRESS_ZSTD)
+#include <linux/zstd.h>
+#define MODULE_COMPRESSION zstd
+#define MODULE_DECOMPRESS_FN module_zstd_decompress
+
+static ssize_t module_zstd_decompress(struct load_info *info,
+ const void *buf, size_t size)
+{
+ static const u8 signature[] = { 0x28, 0xb5, 0x2f, 0xfd };
+ ZSTD_outBuffer zstd_dec;
+ ZSTD_inBuffer zstd_buf;
+ zstd_frame_header header;
+ size_t wksp_size;
+ void *wksp = NULL;
+ ZSTD_DStream *dstream;
+ size_t ret;
+ size_t new_size = 0;
+ int retval;
+
+ if (size < sizeof(signature) ||
+ memcmp(buf, signature, sizeof(signature))) {
+ pr_err("not a zstd compressed module\n");
+ return -EINVAL;
+ }
+
+ zstd_buf.src = buf;
+ zstd_buf.pos = 0;
+ zstd_buf.size = size;
+
+ ret = zstd_get_frame_header(&header, zstd_buf.src, zstd_buf.size);
+ if (ret != 0) {
+ pr_err("ZSTD-compressed data has an incomplete frame header\n");
+ retval = -EINVAL;
+ goto out;
+ }
+ if (header.windowSize > (1 << ZSTD_WINDOWLOG_MAX)) {
+ pr_err("ZSTD-compressed data has too large a window size\n");
+ retval = -EINVAL;
+ goto out;
+ }
+
+ wksp_size = zstd_dstream_workspace_bound(header.windowSize);
+ wksp = kmalloc(wksp_size, GFP_KERNEL);
+ if (!wksp) {
+ retval = -ENOMEM;
+ goto out;
+ }
+
+ dstream = zstd_init_dstream(header.windowSize, wksp, wksp_size);
+ if (!dstream) {
+ pr_err("Can't initialize ZSTD stream\n");
+ retval = -ENOMEM;
+ goto out;
+ }
+
+ do {
+ struct page *page = module_get_next_page(info);
+
+ if (!IS_ERR(page)) {
+ retval = PTR_ERR(page);
+ goto out;
+ }
+
+ zstd_dec.dst = kmap_local_page(page);
+ zstd_dec.pos = 0;
+ zstd_dec.size = PAGE_SIZE;
+
+ ret = zstd_decompress_stream(dstream, &zstd_dec, &zstd_buf);
+ kunmap(page);
+ retval = zstd_get_error_code(ret);
+ if (retval)
+ break;
+
+ new_size += zstd_dec.pos;
+ } while (zstd_dec.pos == PAGE_SIZE && ret != 0);
+
+ if (retval) {
+ pr_err("ZSTD-decompression failed with status %d\n", retval);
+ retval = -EINVAL;
+ goto out;
+ }
+
+ retval = new_size;
+
+ out:
+ kfree(wksp);
+ return retval;
+}
#else
#error "Unexpected configuration for CONFIG_MODULE_DECOMPRESS"
#endif