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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/alpha/lib/strncat.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/alpha/lib/strncat.S')
-rw-r--r--arch/alpha/lib/strncat.S86
1 files changed, 86 insertions, 0 deletions
diff --git a/arch/alpha/lib/strncat.S b/arch/alpha/lib/strncat.S
new file mode 100644
index 000000000..a913a7c84
--- /dev/null
+++ b/arch/alpha/lib/strncat.S
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * arch/alpha/lib/strncat.S
+ * Contributed by Richard Henderson (rth@tamu.edu)
+ *
+ * Append no more than COUNT characters from the null-terminated string SRC
+ * to the null-terminated string DST. Always null-terminate the new DST.
+ *
+ * This differs slightly from the semantics in libc in that we never write
+ * past count, whereas libc may write to count+1. This follows the generic
+ * implementation in lib/string.c and is, IMHO, more sensible.
+ */
+#include <linux/export.h>
+ .text
+
+ .align 3
+ .globl strncat
+ .ent strncat
+strncat:
+ .frame $30, 0, $26
+ .prologue 0
+
+ mov $16, $0 # set up return value
+ beq $18, $zerocount
+
+ /* Find the end of the string. */
+
+ ldq_u $1, 0($16) # load first quadword ($16 may be misaligned)
+ lda $2, -1($31)
+ insqh $2, $16, $2
+ andnot $16, 7, $16
+ or $2, $1, $1
+ cmpbge $31, $1, $2 # bits set iff byte == 0
+ bne $2, $found
+
+$loop: ldq $1, 8($16)
+ addq $16, 8, $16
+ cmpbge $31, $1, $2
+ beq $2, $loop
+
+$found: negq $2, $3 # clear all but least set bit
+ and $2, $3, $2
+
+ and $2, 0xf0, $3 # binary search for that set bit
+ and $2, 0xcc, $4
+ and $2, 0xaa, $5
+ cmovne $3, 4, $3
+ cmovne $4, 2, $4
+ cmovne $5, 1, $5
+ addq $3, $4, $3
+ addq $16, $5, $16
+ addq $16, $3, $16
+
+ /* Now do the append. */
+
+ bsr $23, __stxncpy
+
+ /* Worry about the null termination. */
+
+ zapnot $1, $27, $2 # was last byte a null?
+ bne $2, 0f
+ ret
+
+0: cmplt $27, $24, $2 # did we fill the buffer completely?
+ or $2, $18, $2
+ bne $2, 2f
+
+ and $24, 0x80, $2 # no zero next byte
+ bne $2, 1f
+
+ /* Here there are bytes left in the current word. Clear one. */
+ addq $24, $24, $24 # end-of-count bit <<= 1
+2: zap $1, $24, $1
+ stq_u $1, 0($16)
+ ret
+
+1: /* Here we must read the next DST word and clear the first byte. */
+ ldq_u $1, 8($16)
+ zap $1, 1, $1
+ stq_u $1, 8($16)
+
+$zerocount:
+ ret
+
+ .end strncat
+ EXPORT_SYMBOL(strncat)