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powerpc/inst: Avoid pointer dereferencing in ppc_inst_equal()

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Avoid casting/dereferencing ppc_inst() as u64* , check each member
of the struct when relevant.

And remove the 0xff initialisation of the suffix for non
prefixed instruction. An instruction with 0xff as a suffix
might be invalid, but still is a prefixed instruction and
has to be considered as this.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d8b155e930b7a9708ca110e8ff0ace6713a7af75.1621516826.git.christophe.leroy@csgroup.eu
This commit is contained in:
Christophe Leroy 2021-05-20 13:50:41 +00:00 committed by Michael Ellerman
parent 042e0860e1
commit 036b5560be
1 changed files with 9 additions and 10 deletions
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19
arch/powerpc/include/asm/inst.h
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@ -61,7 +61,7 @@ static inline int ppc_inst_primary_opcode(struct ppc_inst x)
}
#ifdef CONFIG_PPC64
#define ppc_inst(x) ((struct ppc_inst){ .val = (x), .suffix = 0xff })
#define ppc_inst(x) ((struct ppc_inst){ .val = (x) })
#define ppc_inst_prefix(x, y) ((struct ppc_inst){ .val = (x), .suffix = (y) })
@ -72,7 +72,7 @@ static inline u32 ppc_inst_suffix(struct ppc_inst x)
static inline bool ppc_inst_prefixed(struct ppc_inst x)
{
return ppc_inst_primary_opcode(x) == OP_PREFIX && ppc_inst_suffix(x) != 0xff;
return ppc_inst_primary_opcode(x) == OP_PREFIX;
}
static inline struct ppc_inst ppc_inst_swab(struct ppc_inst x)
@ -93,11 +93,6 @@ static inline struct ppc_inst ppc_inst_read(const struct ppc_inst *ptr)
}
}
static inline bool ppc_inst_equal(struct ppc_inst x, struct ppc_inst y)
{
return *(u64 *)&x == *(u64 *)&y;
}
#else
#define ppc_inst(x) ((struct ppc_inst){ .val = x })
@ -124,13 +119,17 @@ static inline struct ppc_inst ppc_inst_read(const struct ppc_inst *ptr)
return *ptr;
}
#endif /* CONFIG_PPC64 */
static inline bool ppc_inst_equal(struct ppc_inst x, struct ppc_inst y)
{
return ppc_inst_val(x) == ppc_inst_val(y);
if (ppc_inst_val(x) != ppc_inst_val(y))
return false;
if (!ppc_inst_prefixed(x))
return true;
return ppc_inst_suffix(x) == ppc_inst_suffix(y);
}
#endif /* CONFIG_PPC64 */
static inline int ppc_inst_len(struct ppc_inst x)
{
return ppc_inst_prefixed(x) ? 8 : 4;