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authorSven Schnelle <svens@linux.ibm.com>2026-09-09 11:29:53 +0200
committerMasami Hiramatsu (Google) <mhiramat@kernel.org>2026-09-10 08:43:35 +0900
commitd22c3e0088e85be8131f7a9283f759cdbb20726d (patch)
tree9668df2aa27b26f850d3ba5ba1287e443803675c /arch/x86/lib/getuser.S
downloadlinux-stable-d22c3e0088e85be8131f7a9283f759cdbb20726d.tar.gz
linux-stable-d22c3e0088e85be8131f7a9283f759cdbb20726d.zip
selftests/ftrace: Fix unique symbol check in kprobe_non_uniq_symbol.tcgrafted
The current regex also matches symbols in modules, which makes the test fail on s390 where name_show is present only once in the kernel, but also multiple times in modules: 000001b1401cdc20 t name_show 000001b0c05e6c40 t name_show [mdev] 000001b0c0495f30 t name_show [i2c_core] Fix this by changing the regular expression to only match the function name. Link: https://lore.kernel.org/all/20260909092954.2200558-1-svens@linux.ibm.com/ Fixes: 03b80ff8023a ("selftests/ftrace: Add new test case which checks non unique symbol") Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Diffstat (limited to 'arch/x86/lib/getuser.S')
-rw-r--r--arch/x86/lib/getuser.S172
1 files changed, 172 insertions, 0 deletions
diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S
new file mode 100644
index 000000000..9d5654b8a
--- /dev/null
+++ b/arch/x86/lib/getuser.S
@@ -0,0 +1,172 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * __get_user functions.
+ *
+ * (C) Copyright 1998 Linus Torvalds
+ * (C) Copyright 2005 Andi Kleen
+ * (C) Copyright 2008 Glauber Costa
+ *
+ * These functions have a non-standard call interface
+ * to make them more efficient, especially as they
+ * return an error value in addition to the "real"
+ * return value.
+ */
+
+/*
+ * __get_user_X
+ *
+ * Inputs: %[r|e]ax contains the address.
+ *
+ * Outputs: %[r|e]ax is error code (0 or -EFAULT)
+ * %[r|e]dx contains zero-extended value
+ * %ecx contains the high half for 32-bit __get_user_8
+ *
+ *
+ * These functions should not modify any other registers,
+ * as they get called from within inline assembly.
+ */
+
+#include <linux/export.h>
+#include <linux/linkage.h>
+#include <linux/objtool.h>
+#include <asm/page_types.h>
+#include <asm/errno.h>
+#include <asm/asm-offsets.h>
+#include <asm/thread_info.h>
+#include <asm/asm.h>
+#include <asm/smap.h>
+#include <asm/runtime-const.h>
+
+#define ASM_BARRIER_NOSPEC ALTERNATIVE "", "lfence", X86_FEATURE_LFENCE_RDTSC
+
+.macro check_range size:req
+.if IS_ENABLED(CONFIG_X86_64)
+ RUNTIME_CONST_PTR USER_PTR_MAX, rdx
+ cmp %rdx, %rax
+ cmova %rdx, %rax
+.else
+ cmp $TASK_SIZE_MAX-\size+1, %eax
+ jae .Lbad_get_user
+ sbb %edx, %edx /* array_index_mask_nospec() */
+ and %edx, %eax
+.endif
+.endm
+
+.macro UACCESS op src dst
+1: \op \src,\dst
+ _ASM_EXTABLE_UA(1b, __get_user_handle_exception)
+.endm
+
+
+ .text
+SYM_FUNC_START(__get_user_1)
+ ANNOTATE_NOENDBR
+ check_range size=1
+ ASM_STAC
+ UACCESS movzbl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_1)
+EXPORT_SYMBOL(__get_user_1)
+
+SYM_FUNC_START(__get_user_2)
+ ANNOTATE_NOENDBR
+ check_range size=2
+ ASM_STAC
+ UACCESS movzwl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_2)
+EXPORT_SYMBOL(__get_user_2)
+
+SYM_FUNC_START(__get_user_4)
+ ANNOTATE_NOENDBR
+ check_range size=4
+ ASM_STAC
+ UACCESS movl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_4)
+EXPORT_SYMBOL(__get_user_4)
+
+SYM_FUNC_START(__get_user_8)
+ ANNOTATE_NOENDBR
+#ifndef CONFIG_X86_64
+ xor %ecx,%ecx
+#endif
+ check_range size=8
+ ASM_STAC
+#ifdef CONFIG_X86_64
+ UACCESS movq (%_ASM_AX),%rdx
+#else
+ UACCESS movl (%_ASM_AX),%edx
+ UACCESS movl 4(%_ASM_AX),%ecx
+#endif
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_8)
+EXPORT_SYMBOL(__get_user_8)
+
+/* .. and the same for __get_user, just without the range checks */
+SYM_FUNC_START(__get_user_nocheck_1)
+ ANNOTATE_NOENDBR
+ ASM_STAC
+ ASM_BARRIER_NOSPEC
+ UACCESS movzbl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_nocheck_1)
+EXPORT_SYMBOL(__get_user_nocheck_1)
+
+SYM_FUNC_START(__get_user_nocheck_2)
+ ANNOTATE_NOENDBR
+ ASM_STAC
+ ASM_BARRIER_NOSPEC
+ UACCESS movzwl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_nocheck_2)
+EXPORT_SYMBOL(__get_user_nocheck_2)
+
+SYM_FUNC_START(__get_user_nocheck_4)
+ ANNOTATE_NOENDBR
+ ASM_STAC
+ ASM_BARRIER_NOSPEC
+ UACCESS movl (%_ASM_AX),%edx
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_nocheck_4)
+EXPORT_SYMBOL(__get_user_nocheck_4)
+
+SYM_FUNC_START(__get_user_nocheck_8)
+ ANNOTATE_NOENDBR
+ ASM_STAC
+ ASM_BARRIER_NOSPEC
+#ifdef CONFIG_X86_64
+ UACCESS movq (%_ASM_AX),%rdx
+#else
+ xor %ecx,%ecx
+ UACCESS movl (%_ASM_AX),%edx
+ UACCESS movl 4(%_ASM_AX),%ecx
+#endif
+ xor %eax,%eax
+ ASM_CLAC
+ RET
+SYM_FUNC_END(__get_user_nocheck_8)
+EXPORT_SYMBOL(__get_user_nocheck_8)
+
+
+SYM_CODE_START_LOCAL(__get_user_handle_exception)
+ ASM_CLAC
+.Lbad_get_user:
+ xor %edx,%edx
+ mov $(-EFAULT),%_ASM_AX
+ RET
+SYM_CODE_END(__get_user_handle_exception)