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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/strrchr.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/strrchr.S')
-rw-r--r--arch/alpha/lib/strrchr.S89
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/alpha/lib/strrchr.S b/arch/alpha/lib/strrchr.S
new file mode 100644
index 000000000..dd8e073b6
--- /dev/null
+++ b/arch/alpha/lib/strrchr.S
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * arch/alpha/lib/strrchr.S
+ * Contributed by Richard Henderson (rth@tamu.edu)
+ *
+ * Return the address of the last occurrence of a given character
+ * within a null-terminated string, or null if it is not found.
+ */
+#include <linux/export.h>
+#include <asm/regdef.h>
+
+ .set noreorder
+ .set noat
+
+ .align 3
+ .ent strrchr
+ .globl strrchr
+strrchr:
+ .frame sp, 0, ra
+ .prologue 0
+
+ zapnot a1, 1, a1 # e0 : zero extend our test character
+ mov zero, t6 # .. e1 : t6 is last match aligned addr
+ sll a1, 8, t5 # e0 : replicate our test character
+ mov zero, t8 # .. e1 : t8 is last match byte compare mask
+ or t5, a1, a1 # e0 :
+ ldq_u t0, 0(a0) # .. e1 : load first quadword
+ sll a1, 16, t5 # e0 :
+ andnot a0, 7, v0 # .. e1 : align source addr
+ or t5, a1, a1 # e0 :
+ lda t4, -1 # .. e1 : build garbage mask
+ sll a1, 32, t5 # e0 :
+ cmpbge zero, t0, t1 # .. e1 : bits set iff byte == zero
+ mskqh t4, a0, t4 # e0 :
+ or t5, a1, a1 # .. e1 : character replication complete
+ xor t0, a1, t2 # e0 : make bytes == c zero
+ cmpbge zero, t4, t4 # .. e1 : bits set iff byte is garbage
+ cmpbge zero, t2, t3 # e0 : bits set iff byte == c
+ andnot t1, t4, t1 # .. e1 : clear garbage from null test
+ andnot t3, t4, t3 # e0 : clear garbage from char test
+ bne t1, $eos # .. e1 : did we already hit the terminator?
+
+ /* Character search main loop */
+$loop:
+ ldq t0, 8(v0) # e0 : load next quadword
+ cmovne t3, v0, t6 # .. e1 : save previous comparisons match
+ cmovne t3, t3, t8 # e0 :
+ addq v0, 8, v0 # .. e1 :
+ xor t0, a1, t2 # e0 :
+ cmpbge zero, t0, t1 # .. e1 : bits set iff byte == zero
+ cmpbge zero, t2, t3 # e0 : bits set iff byte == c
+ beq t1, $loop # .. e1 : if we havnt seen a null, loop
+
+ /* Mask out character matches after terminator */
+$eos:
+ negq t1, t4 # e0 : isolate first null byte match
+ and t1, t4, t4 # e1 :
+ subq t4, 1, t5 # e0 : build a mask of the bytes up to...
+ or t4, t5, t4 # e1 : ... and including the null
+
+ and t3, t4, t3 # e0 : mask out char matches after null
+ cmovne t3, t3, t8 # .. e1 : save it, if match found
+ cmovne t3, v0, t6 # e0 :
+
+ /* Locate the address of the last matched character */
+
+ /* Retain the early exit for the ev4 -- the ev5 mispredict penalty
+ is 5 cycles -- the same as just falling through. */
+ beq t8, $retnull # .. e1 :
+
+ and t8, 0xf0, t2 # e0 : binary search for the high bit set
+ cmovne t2, t2, t8 # .. e1 (zdb)
+ cmovne t2, 4, t2 # e0 :
+ and t8, 0xcc, t1 # .. e1 :
+ cmovne t1, t1, t8 # e0 :
+ cmovne t1, 2, t1 # .. e1 :
+ and t8, 0xaa, t0 # e0 :
+ cmovne t0, 1, t0 # .. e1 (zdb)
+ addq t2, t1, t1 # e0 :
+ addq t6, t0, v0 # .. e1 : add our aligned base ptr to the mix
+ addq v0, t1, v0 # e0 :
+ ret # .. e1 :
+
+$retnull:
+ mov zero, v0 # e0 :
+ ret # .. e1 :
+
+ .end strrchr
+ EXPORT_SYMBOL(strrchr)