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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/perf/callchain.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/perf/callchain.c')
-rw-r--r--arch/powerpc/perf/callchain.c115
1 files changed, 115 insertions, 0 deletions
diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c
new file mode 100644
index 000000000..992cc5c98
--- /dev/null
+++ b/arch/powerpc/perf/callchain.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Performance counter callchain support - powerpc architecture code
+ *
+ * Copyright © 2009 Paul Mackerras, IBM Corporation.
+ */
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/perf_event.h>
+#include <linux/percpu.h>
+#include <linux/uaccess.h>
+#include <linux/mm.h>
+#include <asm/ptrace.h>
+#include <asm/sigcontext.h>
+#include <asm/ucontext.h>
+#include <asm/vdso.h>
+#include <asm/pte-walk.h>
+
+#include "callchain.h"
+
+/*
+ * Is sp valid as the address of the next kernel stack frame after prev_sp?
+ * The next frame may be in a different stack area but should not go
+ * back down in the same stack area.
+ */
+static int valid_next_sp(unsigned long sp, unsigned long prev_sp)
+{
+ if (sp & 0xf)
+ return 0; /* must be 16-byte aligned */
+ if (!validate_sp(sp, current))
+ return 0;
+ if (sp >= prev_sp + STACK_FRAME_MIN_SIZE)
+ return 1;
+ /*
+ * sp could decrease when we jump off an interrupt stack
+ * back to the regular process stack.
+ */
+ if ((sp & ~(THREAD_SIZE - 1)) != (prev_sp & ~(THREAD_SIZE - 1)))
+ return 1;
+ return 0;
+}
+
+void __no_sanitize_address
+perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs)
+{
+ unsigned long sp, next_sp;
+ unsigned long next_ip;
+ unsigned long lr;
+ long level = 0;
+ unsigned long *fp;
+
+ lr = regs->link;
+ sp = regs->gpr[1];
+ perf_callchain_store(entry, perf_arch_instruction_pointer(regs));
+
+ if (!validate_sp(sp, current))
+ return;
+
+ for (;;) {
+ fp = (unsigned long *) sp;
+ next_sp = fp[0];
+
+ if (next_sp == sp + STACK_INT_FRAME_SIZE &&
+ validate_sp_size(sp, current, STACK_INT_FRAME_SIZE) &&
+ fp[STACK_INT_FRAME_MARKER_LONGS] == STACK_FRAME_REGS_MARKER) {
+ /*
+ * This looks like an interrupt frame for an
+ * interrupt that occurred in the kernel
+ */
+ regs = (struct pt_regs *)(sp + STACK_INT_FRAME_REGS);
+ next_ip = regs->nip;
+ lr = regs->link;
+ level = 0;
+ perf_callchain_store_context(entry, PERF_CONTEXT_KERNEL);
+
+ } else {
+ if (level == 0)
+ next_ip = lr;
+ else
+ next_ip = fp[STACK_FRAME_LR_SAVE];
+
+ /*
+ * We can't tell which of the first two addresses
+ * we get are valid, but we can filter out the
+ * obviously bogus ones here. We replace them
+ * with 0 rather than removing them entirely so
+ * that userspace can tell which is which.
+ */
+ if ((level == 1 && next_ip == lr) ||
+ (level <= 1 && !kernel_text_address(next_ip)))
+ next_ip = 0;
+
+ ++level;
+ }
+
+ perf_callchain_store(entry, next_ip);
+ if (!valid_next_sp(next_sp, sp))
+ return;
+ sp = next_sp;
+ }
+}
+
+void
+perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs)
+{
+ perf_callchain_store(entry, perf_arch_instruction_pointer(regs));
+
+ if (!current->mm)
+ return;
+
+ if (!is_32bit_task())
+ perf_callchain_user_64(entry, regs);
+ else
+ perf_callchain_user_32(entry, regs);
+}