Merge tag 'for-5.14-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave...

[linux-2.6-microblaze.git] / arch / arm64 / lib / copy_from_user.S

diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S
index 95cd62d..2cf999e 100644 (file)
--- a/arch/arm64/lib/copy_from_user.S
+++ b/arch/arm64/lib/copy_from_user.S
@@ -29,7 +29,7 @@
        .endm
 
        .macro ldrh1 reg, ptr, val
-       user_ldst 9998f, ldtrh, \reg, \ptr, \val
+       user_ldst 9997f, ldtrh, \reg, \ptr, \val
        .endm
 
        .macro strh1 reg, ptr, val
@@ -37,7 +37,7 @@
        .endm
 
        .macro ldr1 reg, ptr, val
-       user_ldst 9998f, ldtr, \reg, \ptr, \val
+       user_ldst 9997f, ldtr, \reg, \ptr, \val
        .endm
 
        .macro str1 reg, ptr, val
@@ -45,7 +45,7 @@
        .endm
 
        .macro ldp1 reg1, reg2, ptr, val
-       user_ldp 9998f, \reg1, \reg2, \ptr, \val
+       user_ldp 9997f, \reg1, \reg2, \ptr, \val
        .endm
 
        .macro stp1 reg1, reg2, ptr, val
@@ -53,8 +53,10 @@
        .endm
 
 end    .req    x5
+srcin  .req    x15
 SYM_FUNC_START(__arch_copy_from_user)
        add     end, x0, x2
+       mov     srcin, x1
 #include "copy_template.S"
        mov     x0, #0                          // Nothing to copy
        ret
@@ -63,6 +65,11 @@ EXPORT_SYMBOL(__arch_copy_from_user)
 
        .section .fixup,"ax"
        .align  2
+9997:  cmp     dst, dstin
+       b.ne    9998f
+       // Before being absolutely sure we couldn't copy anything, try harder
+USER(9998f, ldtrb tmp1w, [srcin])
+       strb    tmp1w, [dst], #1
 9998:  sub     x0, end, dst                    // bytes not copied
        ret
        .previous