[PATCH v2] powerpc/ptrace: Fix cppcheck issue in gpr32_set_common/gpr32_get_common()
From: <hidden>
Date: 2016-09-12 03:12:20
From: Simon Guo <redacted> The ckpt_regs usage in gpr32_set_common/gpr32_get_common() will lead to following cppcheck error at ifndef CONFIG_PPC_TRANSACTIONAL_MEM case: [arch/powerpc/kernel/ptrace.c:2062]: (error) Uninitialized variable: ckpt_regs [arch/powerpc/kernel/ptrace.c:2130]: (error) Uninitialized variable: ckpt_regs The problem is due to gpr32_set_common() used ckpt_regs variable which only makes sense at #ifdef CONFIG_PPC_TRANSACTIONAL_MEM. This patch fix this issue by passing in "regs" parameter instead. Reported-by: Daniel Axtens <redacted> Signed-off-by: Simon Guo <redacted> --- arch/powerpc/kernel/ptrace.c | 74 +++++++++++++++++--------------------------- 1 file changed, 29 insertions(+), 45 deletions(-)
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index bf91658..74eadb4 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c@@ -2065,33 +2065,12 @@ static const struct user_regset_view user_ppc_native_view = { static int gpr32_get_common(struct task_struct *target, const struct user_regset *regset, unsigned int pos, unsigned int count, - void *kbuf, void __user *ubuf, bool tm_active) + void *kbuf, void __user *ubuf, + unsigned long *regs) { - const unsigned long *regs = &target->thread.regs->gpr[0]; - const unsigned long *ckpt_regs; compat_ulong_t *k = kbuf; compat_ulong_t __user *u = ubuf; compat_ulong_t reg; - int i; - -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM - ckpt_regs = &target->thread.ckpt_regs.gpr[0]; -#endif - if (tm_active) { - regs = ckpt_regs; - } else { - if (target->thread.regs == NULL) - return -EIO; - - if (!FULL_REGS(target->thread.regs)) { - /* - * We have a partial register set. - * Fill 14-31 with bogus values. - */ - for (i = 14; i < 32; i++) - target->thread.regs->gpr[i] = NV_REG_POISON; - } - } pos /= sizeof(reg); count /= sizeof(reg);
@@ -2133,29 +2112,13 @@ static int gpr32_get_common(struct task_struct *target, static int gpr32_set_common(struct task_struct *target, const struct user_regset *regset, unsigned int pos, unsigned int count, - const void *kbuf, const void __user *ubuf, bool tm_active) + const void *kbuf, const void __user *ubuf, + unsigned long *regs) { - unsigned long *regs = &target->thread.regs->gpr[0]; - unsigned long *ckpt_regs; const compat_ulong_t *k = kbuf; const compat_ulong_t __user *u = ubuf; compat_ulong_t reg; -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM - ckpt_regs = &target->thread.ckpt_regs.gpr[0]; -#endif - - if (tm_active) { - regs = ckpt_regs; - } else { - regs = &target->thread.regs->gpr[0]; - - if (target->thread.regs == NULL) - return -EIO; - - CHECK_FULL_REGS(target->thread.regs); - } - pos /= sizeof(reg); count /= sizeof(reg);
@@ -2220,7 +2183,8 @@ static int tm_cgpr32_get(struct task_struct *target, unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf) { - return gpr32_get_common(target, regset, pos, count, kbuf, ubuf, 1); + return gpr32_get_common(target, regset, pos, count, kbuf, ubuf, + &target->thread.ckpt_regs.gpr[0]); } static int tm_cgpr32_set(struct task_struct *target,
@@ -2228,7 +2192,8 @@ static int tm_cgpr32_set(struct task_struct *target, unsigned int pos, unsigned int count, const void *kbuf, const void __user *ubuf) { - return gpr32_set_common(target, regset, pos, count, kbuf, ubuf, 1); + return gpr32_set_common(target, regset, pos, count, kbuf, ubuf, + &target->thread.ckpt_regs.gpr[0]); } #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
@@ -2237,7 +2202,21 @@ static int gpr32_get(struct task_struct *target, unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf) { - return gpr32_get_common(target, regset, pos, count, kbuf, ubuf, 0); + int i; + + if (target->thread.regs == NULL) + return -EIO; + + if (!FULL_REGS(target->thread.regs)) { + /* + * We have a partial register set. + * Fill 14-31 with bogus values. + */ + for (i = 14; i < 32; i++) + target->thread.regs->gpr[i] = NV_REG_POISON; + } + return gpr32_get_common(target, regset, pos, count, kbuf, ubuf, + &target->thread.regs->gpr[0]); } static int gpr32_set(struct task_struct *target,
@@ -2245,7 +2224,12 @@ static int gpr32_set(struct task_struct *target, unsigned int pos, unsigned int count, const void *kbuf, const void __user *ubuf) { - return gpr32_set_common(target, regset, pos, count, kbuf, ubuf, 0); + if (target->thread.regs == NULL) + return -EIO; + + CHECK_FULL_REGS(target->thread.regs); + return gpr32_set_common(target, regset, pos, count, kbuf, ubuf, + &target->thread.regs->gpr[0]); } /*
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1.8.3.1