Since commit f0e98c387e ("[SPARC]: Fix
link errors with gcc-4.3") the MNA trap handler does not emulate
stores to unaligned addresses correctly. MNA operation from both
kernel and user space are affected.
A typical effect of this bug is nr_frags in skbs are overwritten
during buffer copying/checksum-calculation, or maximally 6 bytes
of data in the network buffer will be overwitten with garbage.
Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
		
	
			
		
			
				
	
	
		
			153 lines
		
	
	
	
		
			2.9 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			153 lines
		
	
	
	
		
			2.9 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
/* una_asm.S: Kernel unaligned trap assembler helpers.
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 *
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 * Copyright (C) 1996,2005,2008 David S. Miller (davem@davemloft.net)
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 * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
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 */
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#include <linux/errno.h>
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	.text
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retl_efault:
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	retl
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	 mov	-EFAULT, %o0
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	/* int __do_int_store(unsigned long *dst_addr, int size,
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	 *                    unsigned long *src_val)
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	 *
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	 * %o0 = dest_addr
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	 * %o1 = size
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	 * %o2 = src_val
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	 *
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	 * Return '0' on success, -EFAULT on failure.
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	 */
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	.globl	__do_int_store
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__do_int_store:
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	ld	[%o2], %g1
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	cmp	%o1, 2
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	be	2f
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	 cmp	%o1, 4
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	be	1f
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	 srl	%g1, 24, %g2
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	srl	%g1, 16, %g7
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4:	stb	%g2, [%o0]
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	srl	%g1, 8, %g2
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5:	stb	%g7, [%o0 + 1]
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	ld	[%o2 + 4], %g7
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6:	stb	%g2, [%o0 + 2]
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	srl	%g7, 24, %g2
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7:	stb	%g1, [%o0 + 3]
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	srl	%g7, 16, %g1
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8:	stb	%g2, [%o0 + 4]
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	srl	%g7, 8, %g2
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9:	stb	%g1, [%o0 + 5]
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10:	stb	%g2, [%o0 + 6]
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	b	0f
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11:	 stb	%g7, [%o0 + 7]
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1:	srl	%g1, 16, %g7
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12:	stb	%g2, [%o0]
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	srl	%g1, 8, %g2
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13:	stb	%g7, [%o0 + 1]
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14:	stb	%g2, [%o0 + 2]
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	b	0f
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15:	 stb	%g1, [%o0 + 3]
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2:	srl	%g1, 8, %g2
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16:	stb	%g2, [%o0]
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17:	stb	%g1, [%o0 + 1]
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0:	retl
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	 mov	0, %o0
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	.section __ex_table,#alloc
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	.word	4b, retl_efault
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	.word	5b, retl_efault
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	.word	6b, retl_efault
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	.word	7b, retl_efault
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	.word	8b, retl_efault
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	.word	9b, retl_efault
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	.word	10b, retl_efault
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	.word	11b, retl_efault
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	.word	12b, retl_efault
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	.word	13b, retl_efault
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	.word	14b, retl_efault
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	.word	15b, retl_efault
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	.word	16b, retl_efault
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	.word	17b, retl_efault
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	.previous
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	/* int do_int_load(unsigned long *dest_reg, int size,
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	 *                 unsigned long *saddr, int is_signed)
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	 *
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	 * %o0 = dest_reg
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	 * %o1 = size
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	 * %o2 = saddr
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	 * %o3 = is_signed
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	 *
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	 * Return '0' on success, -EFAULT on failure.
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	 */
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	.globl	do_int_load
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do_int_load:
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	cmp	%o1, 8
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	be	9f
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	 cmp	%o1, 4
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	be	6f
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4:	 ldub	[%o2], %g1
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5:	ldub	[%o2 + 1], %g2
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	sll	%g1, 8, %g1
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	tst	%o3
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	be	3f
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	 or	%g1, %g2, %g1
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	sll	%g1, 16, %g1
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	sra	%g1, 16, %g1
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3:	b	0f
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	 st	%g1, [%o0]
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6:	ldub	[%o2 + 1], %g2
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	sll	%g1, 24, %g1
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7:	ldub	[%o2 + 2], %g7
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	sll	%g2, 16, %g2
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8:	ldub	[%o2 + 3], %g3
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	sll	%g7, 8, %g7
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	or	%g3, %g2, %g3
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	or	%g7, %g3, %g7
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	or	%g1, %g7, %g1
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	b	0f
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	 st	%g1, [%o0]
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9:	ldub	[%o2], %g1
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10:	ldub	[%o2 + 1], %g2
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	sll	%g1, 24, %g1
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11:	ldub	[%o2 + 2], %g7
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	sll	%g2, 16, %g2
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12:	ldub	[%o2 + 3], %g3
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	sll	%g7, 8, %g7
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	or	%g1, %g2, %g1
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	or	%g7, %g3, %g7
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	or	%g1, %g7, %g7
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13:	ldub	[%o2 + 4], %g1
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	st	%g7, [%o0]
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14:	ldub	[%o2 + 5], %g2
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	sll	%g1, 24, %g1
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15:	ldub	[%o2 + 6], %g7
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	sll	%g2, 16, %g2
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16:	ldub	[%o2 + 7], %g3
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	sll	%g7, 8, %g7
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	or	%g1, %g2, %g1
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	or	%g7, %g3, %g7
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	or	%g1, %g7, %g7
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	st	%g7, [%o0 + 4]
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0:	retl
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	 mov	0, %o0
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	.section __ex_table,#alloc
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	.word	4b, retl_efault
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	.word	5b, retl_efault
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	.word	6b, retl_efault
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	.word	7b, retl_efault
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	.word	8b, retl_efault
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	.word	9b, retl_efault
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	.word	10b, retl_efault
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	.word	11b, retl_efault
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	.word	12b, retl_efault
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	.word	13b, retl_efault
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	.word	14b, retl_efault
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	.word	15b, retl_efault
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	.word	16b, retl_efault
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	.previous
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