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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /arch/powerpc/boot/decompress.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'arch/powerpc/boot/decompress.c')
-rw-r--r--arch/powerpc/boot/decompress.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/powerpc/boot/decompress.c b/arch/powerpc/boot/decompress.c
new file mode 100644
index 000000000..6835cb53f
--- /dev/null
+++ b/arch/powerpc/boot/decompress.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Wrapper around the kernel's pre-boot decompression library.
+ *
+ * Copyright (C) IBM Corporation 2016.
+ */
+
+#include "elf.h"
+#include "page.h"
+#include "string.h"
+#include "stdio.h"
+#include "ops.h"
+#include "reg.h"
+#include "types.h"
+
+/*
+ * The decompressor_*.c files play #ifdef games so they can be used in both
+ * pre-boot and regular kernel code. We need these definitions to make the
+ * includes work.
+ */
+
+#define STATIC static
+#define INIT
+
+/*
+ * The build process will copy the required zlib source files and headers
+ * out of lib/ and "fix" the includes so they do not pull in other kernel
+ * headers.
+ */
+
+#ifdef CONFIG_KERNEL_GZIP
+# include "decompress_inflate.c"
+#endif
+
+#ifdef CONFIG_KERNEL_XZ
+# include "xz_config.h"
+# include "../../../lib/decompress_unxz.c"
+#endif
+
+/* globals for tracking the state of the decompression */
+static unsigned long decompressed_bytes;
+static unsigned long limit;
+static unsigned long skip;
+static char *output_buffer;
+
+/*
+ * flush() is called by __decompress() when the decompressor's scratch buffer is
+ * full.
+ */
+static long flush(void *v, unsigned long buffer_size)
+{
+ unsigned long end = decompressed_bytes + buffer_size;
+ unsigned long size = buffer_size;
+ unsigned long offset = 0;
+ char *in = v;
+ char *out;
+
+ /*
+ * if we hit our decompression limit, we need to fake an error to abort
+ * the in-progress decompression.
+ */
+ if (decompressed_bytes >= limit)
+ return -1;
+
+ /* skip this entire block */
+ if (end <= skip) {
+ decompressed_bytes += buffer_size;
+ return buffer_size;
+ }
+
+ /* skip some data at the start, but keep the rest of the block */
+ if (decompressed_bytes < skip && end > skip) {
+ offset = skip - decompressed_bytes;
+
+ in += offset;
+ size -= offset;
+ decompressed_bytes += offset;
+ }
+
+ out = &output_buffer[decompressed_bytes - skip];
+ size = min(decompressed_bytes + size, limit) - decompressed_bytes;
+
+ memcpy(out, in, size);
+ decompressed_bytes += size;
+
+ return buffer_size;
+}
+
+static void print_err(char *s)
+{
+ /* suppress the "error" when we terminate the decompressor */
+ if (decompressed_bytes >= limit)
+ return;
+
+ printf("Decompression error: '%s'\n\r", s);
+}
+
+/**
+ * partial_decompress - decompresses part or all of a compressed buffer
+ * @inbuf: input buffer
+ * @input_size: length of the input buffer
+ * @outbuf: output buffer
+ * @output_size: length of the output buffer
+ * @_skip: number of output bytes to ignore
+ *
+ * This function takes compressed data from inbuf, decompresses and write it to
+ * outbuf. Once output_size bytes are written to the output buffer, or the
+ * stream is exhausted the function will return the number of bytes that were
+ * decompressed. Otherwise it will return whatever error code the decompressor
+ * reported (NB: This is specific to each decompressor type).
+ *
+ * The skip functionality is mainly there so the program and discover
+ * the size of the compressed image so that it can ask firmware (if present)
+ * for an appropriately sized buffer.
+ */
+long partial_decompress(void *inbuf, unsigned long input_size,
+ void *outbuf, unsigned long output_size, unsigned long _skip)
+{
+ int ret;
+
+ /*
+ * The skipped bytes needs to be included in the size of data we want
+ * to decompress.
+ */
+ output_size += _skip;
+
+ decompressed_bytes = 0;
+ output_buffer = outbuf;
+ limit = output_size;
+ skip = _skip;
+
+ ret = __decompress(inbuf, input_size, NULL, flush, outbuf,
+ output_size, NULL, print_err);
+
+ /*
+ * If decompression was aborted due to an actual error rather than
+ * a fake error that we used to abort, then we should report it.
+ */
+ if (decompressed_bytes < limit)
+ return ret;
+
+ return decompressed_bytes - skip;
+}