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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/arm64/lib/memchr.S
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/arm64/lib/memchr.S')
-rw-r--r--arch/arm64/lib/memchr.S76
1 files changed, 76 insertions, 0 deletions
diff --git a/arch/arm64/lib/memchr.S b/arch/arm64/lib/memchr.S
new file mode 100644
index 000000000..37a9f2a4f
--- /dev/null
+++ b/arch/arm64/lib/memchr.S
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 Arm Ltd.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * Find a character in an area of memory.
+ *
+ * Parameters:
+ * x0 - buf
+ * x1 - c
+ * x2 - n
+ * Returns:
+ * x0 - address of first occurrence of 'c' or 0
+ */
+
+#define L(label) .L ## label
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+
+#define srcin x0
+#define chrin w1
+#define cntin x2
+
+#define result x0
+
+#define wordcnt x3
+#define rep01 x4
+#define repchr x5
+#define cur_word x6
+#define cur_byte w6
+#define tmp x7
+#define tmp2 x8
+
+ .p2align 4
+ nop
+SYM_FUNC_START(__pi_memchr)
+ and chrin, chrin, #0xff
+ lsr wordcnt, cntin, #3
+ cbz wordcnt, L(byte_loop)
+ mov rep01, #REP8_01
+ mul repchr, x1, rep01
+ and cntin, cntin, #7
+L(word_loop):
+ ldr cur_word, [srcin], #8
+ sub wordcnt, wordcnt, #1
+ eor cur_word, cur_word, repchr
+ sub tmp, cur_word, rep01
+ orr tmp2, cur_word, #REP8_7f
+ bics tmp, tmp, tmp2
+ b.ne L(found_word)
+ cbnz wordcnt, L(word_loop)
+L(byte_loop):
+ cbz cntin, L(not_found)
+ ldrb cur_byte, [srcin], #1
+ sub cntin, cntin, #1
+ cmp cur_byte, chrin
+ b.ne L(byte_loop)
+ sub srcin, srcin, #1
+ ret
+L(found_word):
+CPU_LE( rev tmp, tmp)
+ clz tmp, tmp
+ sub tmp, tmp, #64
+ add result, srcin, tmp, asr #3
+ ret
+L(not_found):
+ mov result, #0
+ ret
+SYM_FUNC_END(__pi_memchr)
+SYM_FUNC_ALIAS_WEAK(memchr, __pi_memchr)
+EXPORT_SYMBOL_NOKASAN(memchr)