Fixed non-fatal out-of-bounds read in SSE2 SIMD code reported by valgrind when decompressing a JPEG image to a bitmap buffer whose size was not a multiple of 16 bytes.

This commit is contained in:
DRC
2011-12-01 10:58:36 +00:00
parent 8ec31e2fb2
commit 90d7c850fa
6 changed files with 220 additions and 0 deletions

View File

@@ -290,6 +290,41 @@ EXTN(jsimd_ycc_rgb_convert_sse2):
movdqa xmmA,xmmD
sub rcx, byte SIZEOF_XMMWORD
.column_st15:
%ifdef STRICT_MEMORY_ACCESS
; Store the lower 8 bytes of xmmA to the output when it has enough
; space.
cmp rcx, byte SIZEOF_MMWORD
jb short .column_st7
movq MMWORD [rdi], xmmA
add rdi, byte SIZEOF_MMWORD
sub rcx, byte SIZEOF_MMWORD
psrldq xmmA, SIZEOF_MMWORD
.column_st7:
; Store the lower 4 bytes of xmmA to the output when it has enough
; space.
cmp rcx, byte SIZEOF_DWORD
jb short .column_st3
movd DWORD [rdi], xmmA
add rdi, byte SIZEOF_DWORD
sub rcx, byte SIZEOF_DWORD
psrldq xmmA, SIZEOF_DWORD
.column_st3:
; Store the lower 2 bytes of rax to the output when it has enough
; space.
movd eax, xmmA
cmp rcx, byte SIZEOF_WORD
jb short .column_st1
mov WORD [rdi], ax
add rdi, byte SIZEOF_WORD
sub rcx, byte SIZEOF_WORD
shr rax, 16
.column_st1:
; Store the lower 1 byte of rax to the output when it has enough
; space.
test rcx, rcx
jz short .nextrow
mov BYTE [rdi], al
%else
mov rax,rcx
xor rcx, byte 0x0F
shl rcx, 2
@@ -329,6 +364,7 @@ EXTN(jsimd_ycc_rgb_convert_sse2):
por xmmE,xmmC
.adj0: ; ----------------
maskmovdqu xmmA,xmmE ; movntdqu XMMWORD [rdi], xmmA
%endif ; STRICT_MEMORY_ACCESS ; ---------------
%else ; RGB_PIXELSIZE == 4 ; -----------
@@ -413,6 +449,22 @@ EXTN(jsimd_ycc_rgb_convert_sse2):
movdqa xmmA,xmmD
sub rcx, byte SIZEOF_XMMWORD/4
.column_st15:
%ifdef STRICT_MEMORY_ACCESS
; Store two pixels (8 bytes) of xmmA to the output when it has enough
; space.
cmp rcx, byte SIZEOF_XMMWORD/8
jb short .column_st7
movq MMWORD [rdi], xmmA
add rdi, byte SIZEOF_XMMWORD/8*4
sub rcx, byte SIZEOF_XMMWORD/8
psrldq xmmA, SIZEOF_XMMWORD/8*4
.column_st7:
; Store one pixel (4 bytes) of xmmA to the output when it has enough
; space.
test rcx, rcx
jz short .nextrow
movd DWORD [rdi], xmmA
%else
cmp rcx, byte SIZEOF_XMMWORD/16
jb near .nextrow
mov rax,rcx
@@ -452,6 +504,7 @@ EXTN(jsimd_ycc_rgb_convert_sse2):
por xmmE,xmmG
.adj0: ; ----------------
maskmovdqu xmmA,xmmE ; movntdqu XMMWORD [rdi], xmmA
%endif ; STRICT_MEMORY_ACCESS ; ---------------
%endif ; RGB_PIXELSIZE ; ---------------