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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /arch/x86/lib/getuser.S
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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)