From d3ccc9781560af051554017c702631560bdc0811 Mon Sep 17 00:00:00 2001
From: "Christopher M. Riedl" <cmr@codefail.de>
Date: Fri, 26 Feb 2021 19:12:59 -0600
Subject: powerpc/signal: Use __get_user() to copy sigset_t

Usually sigset_t is exactly 8B which is a "trivial" size and does not
warrant using __copy_from_user(). Use __get_user() directly in
anticipation of future work to remove the trivial size optimizations
from __copy_from_user().

The ppc32 implementation of get_sigset_t() previously called
copy_from_user() which, unlike __copy_from_user(), calls access_ok().
Replacing this w/ __get_user() (no access_ok()) is fine here since both
callsites in signal_32.c are preceded by an earlier access_ok().

Signed-off-by: Christopher M. Riedl <cmr@codefail.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210227011259.11992-11-cmr@codefail.de
---
 arch/powerpc/kernel/signal_32.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 75ee918a120a..c505b444a613 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -144,7 +144,7 @@ static inline int restore_general_regs(struct pt_regs *regs,
 
 static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
 {
-	return copy_from_user(set, uset, sizeof(*uset));
+	return __get_user_sigset(set, uset);
 }
 
 #define to_user_ptr(p)		((unsigned long)(p))
-- 
cgit 


From f918a81e209f24acb45cd935bcfb78d2c024f6a1 Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Fri, 19 Mar 2021 11:06:53 +0000
Subject: powerpc/signal32: Rename save_user_regs_unsafe() and
 save_general_regs_unsafe()

Convention is to prefix functions with __unsafe_ instead of
suffixing it with _unsafe.

Rename save_user_regs_unsafe() and save_general_regs_unsafe()
accordingly, that is respectively __unsafe_save_general_regs() and
__unsafe_save_user_regs().

Suggested-by: Christopher M. Riedl <cmr@codefail.de>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8cef43607e5b35a7fd0829dec812d88beb570df2.1616151715.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/kernel/signal_32.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index c505b444a613..3b78748d6d85 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -94,7 +94,7 @@ static inline int get_sigset_t(sigset_t *set,
 #define from_user_ptr(p)	compat_ptr(p)
 
 static __always_inline int
-save_general_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame)
+__unsafe_save_general_regs(struct pt_regs *regs, struct mcontext __user *frame)
 {
 	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
 	int val, i;
@@ -151,7 +151,7 @@ static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
 #define from_user_ptr(p)	((void __user *)(p))
 
 static __always_inline int
-save_general_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame)
+__unsafe_save_general_regs(struct pt_regs *regs, struct mcontext __user *frame)
 {
 	WARN_ON(!FULL_REGS(regs));
 	unsafe_copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE, failed);
@@ -177,7 +177,7 @@ static inline int restore_general_regs(struct pt_regs *regs,
 #endif
 
 #define unsafe_save_general_regs(regs, frame, label) do {	\
-	if (save_general_regs_unsafe(regs, frame))	\
+	if (__unsafe_save_general_regs(regs, frame))		\
 		goto label;					\
 } while (0)
 
@@ -260,8 +260,8 @@ static void prepare_save_user_regs(int ctx_has_vsx_region)
 #endif
 }
 
-static int save_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
-				 struct mcontext __user *tm_frame, int ctx_has_vsx_region)
+static int __unsafe_save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
+				   struct mcontext __user *tm_frame, int ctx_has_vsx_region)
 {
 	unsigned long msr = regs->msr;
 
@@ -338,7 +338,7 @@ failed:
 }
 
 #define unsafe_save_user_regs(regs, frame, tm_frame, has_vsx, label) do { \
-	if (save_user_regs_unsafe(regs, frame, tm_frame, has_vsx))	\
+	if (__unsafe_save_user_regs(regs, frame, tm_frame, has_vsx))	\
 		goto label;						\
 } while (0)
 
@@ -350,7 +350,7 @@ failed:
  * We also save the transactional registers to a second ucontext in the
  * frame.
  *
- * See save_user_regs_unsafe() and signal_64.c:setup_tm_sigcontexts().
+ * See __unsafe_save_user_regs() and signal_64.c:setup_tm_sigcontexts().
  */
 static void prepare_save_tm_user_regs(void)
 {
@@ -441,7 +441,7 @@ static int save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user
 #endif /* CONFIG_VSX */
 #ifdef CONFIG_SPE
 	/* SPE regs are not checkpointed with TM, so this section is
-	 * simply the same as in save_user_regs_unsafe().
+	 * simply the same as in __unsafe_save_user_regs().
 	 */
 	if (current->thread.used_spe) {
 		unsafe_copy_to_user(&frame->mc_vregs, current->thread.evr,
-- 
cgit 


From ca9e1605cdd9473a0eb4d6da238d2524be12591a Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Fri, 19 Mar 2021 11:06:54 +0000
Subject: powerpc/signal32: Remove ifdefery in middle of if/else in sigreturn()

In the same spirit as commit f1cf4f93de2f ("powerpc/signal32: Remove
ifdefery in middle of if/else")

MSR_TM_ACTIVE() is always defined and returns always 0 when
CONFIG_PPC_TRANSACTIONAL_MEM is not selected, so the awful
ifdefery in the middle of an if/else can be removed.

Make 'msr_hi' a 'long long' to avoid build failure on PPC32
due to the 32 bits left shift.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a4b48b2f0be1ef13fc8e57452b7f8350da28d521.1616151715.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/kernel/signal_32.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 3b78748d6d85..8dfe4fe77706 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -740,6 +740,12 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 
 	return 0;
 }
+#else
+static long restore_tm_user_regs(struct pt_regs *regs, struct mcontext __user *sr,
+				 struct mcontext __user *tm_sr)
+{
+	return 0;
+}
 #endif
 
 #ifdef CONFIG_PPC64
@@ -1317,10 +1323,9 @@ SYSCALL_DEFINE0(sigreturn)
 	struct mcontext __user *sr;
 	void __user *addr;
 	sigset_t set;
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-	struct mcontext __user *mcp, *tm_mcp;
-	unsigned long msr_hi;
-#endif
+	struct mcontext __user *mcp;
+	struct mcontext __user *tm_mcp = NULL;
+	unsigned long long msr_hi = 0;
 
 	/* Always make any pending restarted system calls return -EINTR */
 	current->restart_block.fn = do_no_restart_syscall;
@@ -1343,19 +1348,18 @@ SYSCALL_DEFINE0(sigreturn)
 #endif
 	set_current_blocked(&set);
 
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	mcp = (struct mcontext __user *)&sf->mctx;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
 	if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
 		goto badframe;
+#endif
 	if (MSR_TM_ACTIVE(msr_hi<<32)) {
 		if (!cpu_has_feature(CPU_FTR_TM))
 			goto badframe;
 		if (restore_tm_user_regs(regs, mcp, tm_mcp))
 			goto badframe;
-	} else
-#endif
-	{
+	} else {
 		sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
 		addr = sr;
 		if (!access_ok(sr, sizeof(*sr))
-- 
cgit 


From 362471b3192e4184fff5fedee1ea20bdf637a0c8 Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Fri, 19 Mar 2021 11:06:55 +0000
Subject: powerpc/signal32: Perform access_ok() inside restore_user_regs()

In preparation of using user_access_begin/end in restore_user_regs(),
move the access_ok() inside the function.

It makes no difference as the behaviour on a failed access_ok() is
the same as on failed restore_user_regs().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c106eb2f37c3040f1fd38b40e50c670feb7cb835.1616151715.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/kernel/signal_32.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 8dfe4fe77706..e2b1d2a0abad 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -492,6 +492,8 @@ static long restore_user_regs(struct pt_regs *regs,
 	int i;
 #endif
 
+	if (!access_ok(sr, sizeof(*sr)))
+		return 1;
 	/*
 	 * restore general registers but not including MSR or SOFTE. Also
 	 * take care of keeping r2 (TLS) intact if not a signal
@@ -963,13 +965,10 @@ static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int
 		if (__get_user(cmcp, &ucp->uc_regs))
 			return -EFAULT;
 		mcp = (struct mcontext __user *)(u64)cmcp;
-		/* no need to check access_ok(mcp), since mcp < 4GB */
 	}
 #else
 	if (__get_user(mcp, &ucp->uc_regs))
 		return -EFAULT;
-	if (!access_ok(mcp, sizeof(*mcp)))
-		return -EFAULT;
 #endif
 	set_current_blocked(&set);
 	if (restore_user_regs(regs, mcp, sig))
@@ -1362,8 +1361,7 @@ SYSCALL_DEFINE0(sigreturn)
 	} else {
 		sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
 		addr = sr;
-		if (!access_ok(sr, sizeof(*sr))
-		    || restore_user_regs(regs, sr, 1))
+		if (restore_user_regs(regs, sr, 1))
 			goto badframe;
 	}
 
-- 
cgit 


From 036fc2cb1dc2245c2ea7d2f03c7af80417b6310c Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Fri, 19 Mar 2021 11:06:56 +0000
Subject: powerpc/signal32: Reorder user reads in restore_tm_user_regs()

In restore_tm_user_regs(), regroup the reads from 'sr' and the ones
from 'tm_sr' together in order to allow two block user accesses
in following patch.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7c518b9a4c8e5ae9a3bfb647bc8b20bf820233af.1616151715.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/kernel/signal_32.c | 49 +++++++++++++++++++++++++++++++----------
 1 file changed, 37 insertions(+), 12 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index e2b1d2a0abad..088c83853026 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -607,8 +607,7 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 	 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
 	 * were set by the signal delivery.
 	 */
-	err = restore_general_regs(regs, tm_sr);
-	err |= restore_general_regs(&current->thread.ckpt_regs, sr);
+	err = restore_general_regs(&current->thread.ckpt_regs, sr);
 
 	err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
 
@@ -624,9 +623,6 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 	if (msr & MSR_VEC) {
 		/* restore altivec registers from the stack */
 		if (__copy_from_user(&current->thread.ckvr_state, &sr->mc_vregs,
-				     sizeof(sr->mc_vregs)) ||
-		    __copy_from_user(&current->thread.vr_state,
-				     &tm_sr->mc_vregs,
 				     sizeof(sr->mc_vregs)))
 			return 1;
 		current->thread.used_vr = true;
@@ -639,9 +635,7 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 
 	/* Always get VRSAVE back */
 	if (__get_user(current->thread.ckvrsave,
-		       (u32 __user *)&sr->mc_vregs[32]) ||
-	    __get_user(current->thread.vrsave,
-		       (u32 __user *)&tm_sr->mc_vregs[32]))
+		       (u32 __user *)&sr->mc_vregs[32]))
 		return 1;
 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 		mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
@@ -649,8 +643,7 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 
 	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
 
-	if (copy_fpr_from_user(current, &sr->mc_fregs) ||
-	    copy_ckfpr_from_user(current, &tm_sr->mc_fregs))
+	if (copy_fpr_from_user(current, &sr->mc_fregs))
 		return 1;
 
 #ifdef CONFIG_VSX
@@ -660,8 +653,7 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 		 * Restore altivec registers from the stack to a local
 		 * buffer, then write this out to the thread_struct
 		 */
-		if (copy_vsx_from_user(current, &tm_sr->mc_vsregs) ||
-		    copy_ckvsx_from_user(current, &sr->mc_vsregs))
+		if (copy_ckvsx_from_user(current, &sr->mc_vsregs))
 			return 1;
 		current->thread.used_vsr = true;
 	} else if (current->thread.used_vsr)
@@ -690,6 +682,39 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 		return 1;
 #endif /* CONFIG_SPE */
 
+	err = restore_general_regs(regs, tm_sr);
+	if (err)
+		return 1;
+
+#ifdef CONFIG_ALTIVEC
+	/* restore altivec registers from the stack */
+	if (msr & MSR_VEC)
+		if (__copy_from_user(&current->thread.vr_state,
+				     &tm_sr->mc_vregs,
+				     sizeof(sr->mc_vregs)))
+			return 1;
+
+	/* Always get VRSAVE back */
+	if (__get_user(current->thread.vrsave,
+		       (u32 __user *)&tm_sr->mc_vregs[32]))
+		return 1;
+#endif /* CONFIG_ALTIVEC */
+
+	if (copy_ckfpr_from_user(current, &tm_sr->mc_fregs))
+		return 1;
+
+#ifdef CONFIG_VSX
+	if (msr & MSR_VSX) {
+		/*
+		 * Restore altivec registers from the stack to a local
+		 * buffer, then write this out to the thread_struct
+		 */
+		if (copy_vsx_from_user(current, &tm_sr->mc_vsregs))
+			return 1;
+		current->thread.used_vsr = true;
+	}
+#endif /* CONFIG_VSX */
+
 	/* Get the top half of the MSR from the user context */
 	if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
 		return 1;
-- 
cgit 


From 627b72bee84d6652e0af26617e71ce2b3c18fcd5 Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Fri, 19 Mar 2021 11:06:57 +0000
Subject: powerpc/signal32: Convert restore_[tm]_user_regs() to user access
 block

Convert restore_user_regs() and restore_tm_user_regs()
to use user_access_read_begin/end blocks.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/181adf15a6f644efcd1aeafb355f3578ff1b6bc5.1616151715.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/include/asm/ptrace.h |   2 +-
 arch/powerpc/kernel/signal_32.c   | 141 +++++++++++++++++++-------------------
 2 files changed, 72 insertions(+), 71 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index f10498e1b3f6..95600f3a6523 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -245,7 +245,7 @@ static inline bool trap_norestart(struct pt_regs *regs)
 	return regs->trap & 0x10;
 }
 
-static inline void set_trap_norestart(struct pt_regs *regs)
+static __always_inline void set_trap_norestart(struct pt_regs *regs)
 {
 	regs->trap |= 0x10;
 }
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 088c83853026..0b1a6f53e553 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -116,8 +116,8 @@ failed:
 	return 1;
 }
 
-static inline int restore_general_regs(struct pt_regs *regs,
-		struct mcontext __user *sr)
+static __always_inline int
+__unsafe_restore_general_regs(struct pt_regs *regs, struct mcontext __user *sr)
 {
 	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
 	int i;
@@ -125,10 +125,12 @@ static inline int restore_general_regs(struct pt_regs *regs,
 	for (i = 0; i <= PT_RESULT; i++) {
 		if ((i == PT_MSR) || (i == PT_SOFTE))
 			continue;
-		if (__get_user(gregs[i], &sr->mc_gregs[i]))
-			return -EFAULT;
+		unsafe_get_user(gregs[i], &sr->mc_gregs[i], failed);
 	}
 	return 0;
+
+failed:
+	return 1;
 }
 
 #else /* CONFIG_PPC64 */
@@ -161,18 +163,20 @@ failed:
 	return 1;
 }
 
-static inline int restore_general_regs(struct pt_regs *regs,
-		struct mcontext __user *sr)
+static __always_inline
+int __unsafe_restore_general_regs(struct pt_regs *regs, struct mcontext __user *sr)
 {
 	/* copy up to but not including MSR */
-	if (__copy_from_user(regs, &sr->mc_gregs,
-				PT_MSR * sizeof(elf_greg_t)))
-		return -EFAULT;
+	unsafe_copy_from_user(regs, &sr->mc_gregs, PT_MSR * sizeof(elf_greg_t), failed);
+
 	/* copy from orig_r3 (the word after the MSR) up to the end */
-	if (__copy_from_user(&regs->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
-				GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
-		return -EFAULT;
+	unsafe_copy_from_user(&regs->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
+			      GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t), failed);
+
 	return 0;
+
+failed:
+	return 1;
 }
 #endif
 
@@ -181,6 +185,11 @@ static inline int restore_general_regs(struct pt_regs *regs,
 		goto label;					\
 } while (0)
 
+#define unsafe_restore_general_regs(regs, frame, label) do {	\
+	if (__unsafe_restore_general_regs(regs, frame))		\
+		goto label;					\
+} while (0)
+
 /*
  * When we have signals to deliver, we set up on the
  * user stack, going down from the original stack pointer:
@@ -485,14 +494,13 @@ static int save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user
 static long restore_user_regs(struct pt_regs *regs,
 			      struct mcontext __user *sr, int sig)
 {
-	long err;
 	unsigned int save_r2 = 0;
 	unsigned long msr;
 #ifdef CONFIG_VSX
 	int i;
 #endif
 
-	if (!access_ok(sr, sizeof(*sr)))
+	if (!user_read_access_begin(sr, sizeof(*sr)))
 		return 1;
 	/*
 	 * restore general registers but not including MSR or SOFTE. Also
@@ -500,13 +508,11 @@ static long restore_user_regs(struct pt_regs *regs,
 	 */
 	if (!sig)
 		save_r2 = (unsigned int)regs->gpr[2];
-	err = restore_general_regs(regs, sr);
+	unsafe_restore_general_regs(regs, sr, failed);
 	set_trap_norestart(regs);
-	err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
+	unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed);
 	if (!sig)
 		regs->gpr[2] = (unsigned long) save_r2;
-	if (err)
-		return 1;
 
 	/* if doing signal return, restore the previous little-endian mode */
 	if (sig)
@@ -520,22 +526,19 @@ static long restore_user_regs(struct pt_regs *regs,
 	regs->msr &= ~MSR_VEC;
 	if (msr & MSR_VEC) {
 		/* restore altivec registers from the stack */
-		if (__copy_from_user(&current->thread.vr_state, &sr->mc_vregs,
-				     sizeof(sr->mc_vregs)))
-			return 1;
+		unsafe_copy_from_user(&current->thread.vr_state, &sr->mc_vregs,
+				      sizeof(sr->mc_vregs), failed);
 		current->thread.used_vr = true;
 	} else if (current->thread.used_vr)
 		memset(&current->thread.vr_state, 0,
 		       ELF_NVRREG * sizeof(vector128));
 
 	/* Always get VRSAVE back */
-	if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
-		return 1;
+	unsafe_get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32], failed);
 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 		mtspr(SPRN_VRSAVE, current->thread.vrsave);
 #endif /* CONFIG_ALTIVEC */
-	if (copy_fpr_from_user(current, &sr->mc_fregs))
-		return 1;
+	unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed);
 
 #ifdef CONFIG_VSX
 	/*
@@ -548,8 +551,7 @@ static long restore_user_regs(struct pt_regs *regs,
 		 * Restore altivec registers from the stack to a local
 		 * buffer, then write this out to the thread_struct
 		 */
-		if (copy_vsx_from_user(current, &sr->mc_vsregs))
-			return 1;
+		unsafe_copy_vsx_from_user(current, &sr->mc_vsregs, failed);
 		current->thread.used_vsr = true;
 	} else if (current->thread.used_vsr)
 		for (i = 0; i < 32 ; i++)
@@ -567,19 +569,22 @@ static long restore_user_regs(struct pt_regs *regs,
 	regs->msr &= ~MSR_SPE;
 	if (msr & MSR_SPE) {
 		/* restore spe registers from the stack */
-		if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
-				     ELF_NEVRREG * sizeof(u32)))
-			return 1;
+		unsafe_copy_from_user(current->thread.evr, &sr->mc_vregs,
+				      ELF_NEVRREG * sizeof(u32));
 		current->thread.used_spe = true;
 	} else if (current->thread.used_spe)
 		memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
 
 	/* Always get SPEFSCR back */
-	if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
-		return 1;
+	unsafe_get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG, failed);
 #endif /* CONFIG_SPE */
 
+	user_read_access_end();
 	return 0;
+
+failed:
+	user_read_access_end();
+	return 1;
 }
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -592,7 +597,6 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 				 struct mcontext __user *sr,
 				 struct mcontext __user *tm_sr)
 {
-	long err;
 	unsigned long msr, msr_hi;
 #ifdef CONFIG_VSX
 	int i;
@@ -607,14 +611,13 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 	 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
 	 * were set by the signal delivery.
 	 */
-	err = restore_general_regs(&current->thread.ckpt_regs, sr);
-
-	err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
-
-	err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
-	if (err)
+	if (!user_read_access_begin(sr, sizeof(*sr)))
 		return 1;
 
+	unsafe_restore_general_regs(&current->thread.ckpt_regs, sr, failed);
+	unsafe_get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP], failed);
+	unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed);
+
 	/* Restore the previous little-endian mode */
 	regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
 
@@ -622,9 +625,8 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 	regs->msr &= ~MSR_VEC;
 	if (msr & MSR_VEC) {
 		/* restore altivec registers from the stack */
-		if (__copy_from_user(&current->thread.ckvr_state, &sr->mc_vregs,
-				     sizeof(sr->mc_vregs)))
-			return 1;
+		unsafe_copy_from_user(&current->thread.ckvr_state, &sr->mc_vregs,
+				      sizeof(sr->mc_vregs), failed);
 		current->thread.used_vr = true;
 	} else if (current->thread.used_vr) {
 		memset(&current->thread.vr_state, 0,
@@ -634,17 +636,15 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 	}
 
 	/* Always get VRSAVE back */
-	if (__get_user(current->thread.ckvrsave,
-		       (u32 __user *)&sr->mc_vregs[32]))
-		return 1;
+	unsafe_get_user(current->thread.ckvrsave,
+			(u32 __user *)&sr->mc_vregs[32], failed);
 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 		mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
 #endif /* CONFIG_ALTIVEC */
 
 	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
 
-	if (copy_fpr_from_user(current, &sr->mc_fregs))
-		return 1;
+	unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed);
 
 #ifdef CONFIG_VSX
 	regs->msr &= ~MSR_VSX;
@@ -653,8 +653,7 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 		 * Restore altivec registers from the stack to a local
 		 * buffer, then write this out to the thread_struct
 		 */
-		if (copy_ckvsx_from_user(current, &sr->mc_vsregs))
-			return 1;
+		unsafe_copy_ckvsx_from_user(current, &sr->mc_vsregs, failed);
 		current->thread.used_vsr = true;
 	} else if (current->thread.used_vsr)
 		for (i = 0; i < 32 ; i++) {
@@ -669,39 +668,36 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 	 */
 	regs->msr &= ~MSR_SPE;
 	if (msr & MSR_SPE) {
-		if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
-				     ELF_NEVRREG * sizeof(u32)))
-			return 1;
+		unsafe_copy_from_user(current->thread.evr, &sr->mc_vregs,
+				      ELF_NEVRREG * sizeof(u32), failed);
 		current->thread.used_spe = true;
 	} else if (current->thread.used_spe)
 		memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
 
 	/* Always get SPEFSCR back */
-	if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
-		       + ELF_NEVRREG))
-		return 1;
+	unsafe_get_user(current->thread.spefscr,
+			(u32 __user *)&sr->mc_vregs + ELF_NEVRREG, failed);
 #endif /* CONFIG_SPE */
 
-	err = restore_general_regs(regs, tm_sr);
-	if (err)
+	user_read_access_end();
+
+	if (!user_read_access_begin(tm_sr, sizeof(*tm_sr)))
 		return 1;
 
+	unsafe_restore_general_regs(regs, tm_sr, failed);
+
 #ifdef CONFIG_ALTIVEC
 	/* restore altivec registers from the stack */
 	if (msr & MSR_VEC)
-		if (__copy_from_user(&current->thread.vr_state,
-				     &tm_sr->mc_vregs,
-				     sizeof(sr->mc_vregs)))
-			return 1;
+		unsafe_copy_from_user(&current->thread.vr_state, &tm_sr->mc_vregs,
+				      sizeof(sr->mc_vregs), failed);
 
 	/* Always get VRSAVE back */
-	if (__get_user(current->thread.vrsave,
-		       (u32 __user *)&tm_sr->mc_vregs[32]))
-		return 1;
+	unsafe_get_user(current->thread.vrsave,
+			(u32 __user *)&tm_sr->mc_vregs[32], failed);
 #endif /* CONFIG_ALTIVEC */
 
-	if (copy_ckfpr_from_user(current, &tm_sr->mc_fregs))
-		return 1;
+	unsafe_copy_ckfpr_from_user(current, &tm_sr->mc_fregs, failed);
 
 #ifdef CONFIG_VSX
 	if (msr & MSR_VSX) {
@@ -709,16 +705,17 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 		 * Restore altivec registers from the stack to a local
 		 * buffer, then write this out to the thread_struct
 		 */
-		if (copy_vsx_from_user(current, &tm_sr->mc_vsregs))
-			return 1;
+		unsafe_copy_vsx_from_user(current, &tm_sr->mc_vsregs, failed);
 		current->thread.used_vsr = true;
 	}
 #endif /* CONFIG_VSX */
 
 	/* Get the top half of the MSR from the user context */
-	if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
-		return 1;
+	unsafe_get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR], failed);
 	msr_hi <<= 32;
+
+	user_read_access_end();
+
 	/* If TM bits are set to the reserved value, it's an invalid context */
 	if (MSR_TM_RESV(msr_hi))
 		return 1;
@@ -766,6 +763,10 @@ static long restore_tm_user_regs(struct pt_regs *regs,
 	preempt_enable();
 
 	return 0;
+
+failed:
+	user_read_access_end();
+	return 1;
 }
 #else
 static long restore_tm_user_regs(struct pt_regs *regs, struct mcontext __user *sr,
-- 
cgit 


From 887f3ceb51cd34109ac17bfc98695162e299e657 Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Fri, 19 Mar 2021 11:06:58 +0000
Subject: powerpc/signal32: Convert do_setcontext[_tm]() to user access block

Add unsafe_get_user_sigset() and transform PPC32 get_sigset_t()
into an unsafe version unsafe_get_sigset_t().

Then convert do_setcontext() and do_setcontext_tm() to use
user_read_access_begin/end.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/9273ba664db769b8d9c7540ae91395e346e4945e.1616151715.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/kernel/signal.h    |  2 ++
 arch/powerpc/kernel/signal_32.c | 42 +++++++++++++++++++++++------------------
 2 files changed, 26 insertions(+), 18 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index a5152ff3c52f..f4aafa337c2e 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -25,6 +25,8 @@ static inline int __get_user_sigset(sigset_t *dst, const sigset_t __user *src)
 
 	return __get_user(dst->sig[0], (u64 __user *)&src->sig[0]);
 }
+#define unsafe_get_user_sigset(dst, src, label) \
+	unsafe_get_user((dst)->sig[0], (u64 __user *)&(src)->sig[0], label)
 
 #ifdef CONFIG_VSX
 extern unsigned long copy_vsx_to_user(void __user *to,
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 0b1a6f53e553..592b889e3836 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -83,12 +83,7 @@
  * implementation that makes things simple for little endian only)
  */
 #define unsafe_put_sigset_t	unsafe_put_compat_sigset
-
-static inline int get_sigset_t(sigset_t *set,
-			       const compat_sigset_t __user *uset)
-{
-	return get_compat_sigset(set, uset);
-}
+#define unsafe_get_sigset_t	unsafe_get_compat_sigset
 
 #define to_user_ptr(p)		ptr_to_compat(p)
 #define from_user_ptr(p)	compat_ptr(p)
@@ -144,10 +139,7 @@ failed:
 	unsafe_copy_to_user(__us, __s, sizeof(*__us), label);		\
 } while (0)
 
-static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
-{
-	return __get_user_sigset(set, uset);
-}
+#define unsafe_get_sigset_t	unsafe_get_user_sigset
 
 #define to_user_ptr(p)		((unsigned long)(p))
 #define from_user_ptr(p)	((void __user *)(p))
@@ -982,25 +974,31 @@ static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int
 	sigset_t set;
 	struct mcontext __user *mcp;
 
-	if (get_sigset_t(&set, &ucp->uc_sigmask))
+	if (user_read_access_begin(ucp, sizeof(*ucp)))
 		return -EFAULT;
+
+	unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
 #ifdef CONFIG_PPC64
 	{
 		u32 cmcp;
 
-		if (__get_user(cmcp, &ucp->uc_regs))
-			return -EFAULT;
+		unsafe_get_user(cmcp, &ucp->uc_regs, failed);
 		mcp = (struct mcontext __user *)(u64)cmcp;
 	}
 #else
-	if (__get_user(mcp, &ucp->uc_regs))
-		return -EFAULT;
+	unsafe_get_user(mcp, &ucp->uc_regs, failed);
 #endif
+	user_read_access_end();
+
 	set_current_blocked(&set);
 	if (restore_user_regs(regs, mcp, sig))
 		return -EFAULT;
 
 	return 0;
+
+failed:
+	user_read_access_end();
+	return -EFAULT;
 }
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -1014,11 +1012,15 @@ static int do_setcontext_tm(struct ucontext __user *ucp,
 	u32 cmcp;
 	u32 tm_cmcp;
 
-	if (get_sigset_t(&set, &ucp->uc_sigmask))
+	if (user_read_access_begin(ucp, sizeof(*ucp)))
 		return -EFAULT;
 
-	if (__get_user(cmcp, &ucp->uc_regs) ||
-	    __get_user(tm_cmcp, &tm_ucp->uc_regs))
+	unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
+	unsafe_get_user(cmcp, &ucp->uc_regs, failed);
+
+	user_read_access_end();
+
+	if (__get_user(tm_cmcp, &tm_ucp->uc_regs))
 		return -EFAULT;
 	mcp = (struct mcontext __user *)(u64)cmcp;
 	tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
@@ -1029,6 +1031,10 @@ static int do_setcontext_tm(struct ucontext __user *ucp,
 		return -EFAULT;
 
 	return 0;
+
+failed:
+	user_read_access_end();
+	return -EFAULT;
 }
 #endif
 
-- 
cgit 


From c7393a71eb1abdda7e3a3ef798bae60de11540ec Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Fri, 19 Mar 2021 11:07:00 +0000
Subject: powerpc/signal32: Simplify logging in sigreturn()

Same spirit as commit debf122c777f ("powerpc/signal32: Simplify logging
in handle_rt_signal32()"), remove this intermediate 'addr' local var.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/638fa99530beb29f82f94370057d110e91272acc.1616151715.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/kernel/signal_32.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 592b889e3836..5be267b3a13e 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -1352,7 +1352,6 @@ SYSCALL_DEFINE0(sigreturn)
 	struct sigcontext __user *sc;
 	struct sigcontext sigctx;
 	struct mcontext __user *sr;
-	void __user *addr;
 	sigset_t set;
 	struct mcontext __user *mcp;
 	struct mcontext __user *tm_mcp = NULL;
@@ -1363,7 +1362,6 @@ SYSCALL_DEFINE0(sigreturn)
 
 	sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
 	sc = &sf->sctx;
-	addr = sc;
 	if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
 		goto badframe;
 
@@ -1392,16 +1390,19 @@ SYSCALL_DEFINE0(sigreturn)
 			goto badframe;
 	} else {
 		sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
-		addr = sr;
-		if (restore_user_regs(regs, sr, 1))
-			goto badframe;
+		if (restore_user_regs(regs, sr, 1)) {
+			signal_fault(current, regs, "sys_sigreturn", sr);
+
+			force_sig(SIGSEGV);
+			return 0;
+		}
 	}
 
 	set_thread_flag(TIF_RESTOREALL);
 	return 0;
 
 badframe:
-	signal_fault(current, regs, "sys_sigreturn", addr);
+	signal_fault(current, regs, "sys_sigreturn", sc);
 
 	force_sig(SIGSEGV);
 	return 0;
-- 
cgit 


From af072b1a9d4d9edc24da84a071b0671e147026cb Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Sun, 11 Apr 2021 16:39:53 +0000
Subject: powerpc/signal32: Fix build failure with CONFIG_SPE

Add missing fault exit label in unsafe_copy_from_user() in order to
avoid following build failure with CONFIG_SPE

  CC      arch/powerpc/kernel/signal_32.o
arch/powerpc/kernel/signal_32.c: In function 'restore_user_regs':
arch/powerpc/kernel/signal_32.c:565:36: error: macro "unsafe_copy_from_user" requires 4 arguments, but only 3 given
  565 |           ELF_NEVRREG * sizeof(u32));
      |                                    ^
In file included from ./include/linux/uaccess.h:11,
                 from ./include/linux/sched/task.h:11,
                 from ./include/linux/sched/signal.h:9,
                 from ./include/linux/rcuwait.h:6,
                 from ./include/linux/percpu-rwsem.h:7,
                 from ./include/linux/fs.h:33,
                 from ./include/linux/huge_mm.h:8,
                 from ./include/linux/mm.h:707,
                 from arch/powerpc/kernel/signal_32.c:17:
./arch/powerpc/include/asm/uaccess.h:428: note: macro "unsafe_copy_from_user" defined here
  428 | #define unsafe_copy_from_user(d, s, l, e) \
      |
arch/powerpc/kernel/signal_32.c:564:3: error: 'unsafe_copy_from_user' undeclared (first use in this function); did you mean 'raw_copy_from_user'?
  564 |   unsafe_copy_from_user(current->thread.evr, &sr->mc_vregs,
      |   ^~~~~~~~~~~~~~~~~~~~~
      |   raw_copy_from_user
arch/powerpc/kernel/signal_32.c:564:3: note: each undeclared identifier is reported only once for each function it appears in
make[3]: *** [arch/powerpc/kernel/signal_32.o] Error 1

Fixes: 627b72bee84d ("powerpc/signal32: Convert restore_[tm]_user_regs() to user access block")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/aad2cb1801a3cc99bc27081022925b9fc18a0dfb.1618159169.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/kernel/signal_32.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 5be267b3a13e..fff4adc5a2b0 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -562,7 +562,7 @@ static long restore_user_regs(struct pt_regs *regs,
 	if (msr & MSR_SPE) {
 		/* restore spe registers from the stack */
 		unsafe_copy_from_user(current->thread.evr, &sr->mc_vregs,
-				      ELF_NEVRREG * sizeof(u32));
+				      ELF_NEVRREG * sizeof(u32), failed);
 		current->thread.used_spe = true;
 	} else if (current->thread.used_spe)
 		memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
-- 
cgit 


From 8dc7f0229b7892ccb23e19c9f30511c68cc0fdcc Mon Sep 17 00:00:00 2001
From: Nicholas Piggin <npiggin@gmail.com>
Date: Tue, 16 Mar 2021 20:42:04 +1000
Subject: powerpc: remove partial register save logic

All subarchitectures always save all GPRs to pt_regs interrupt frames
now. Remove FULL_REGS and associated bits.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-11-npiggin@gmail.com
---
 arch/powerpc/include/asm/ptrace.h        | 17 ++---------------
 arch/powerpc/kernel/align.c              |  6 ------
 arch/powerpc/kernel/interrupt.c          |  3 ---
 arch/powerpc/kernel/process.c            | 12 ------------
 arch/powerpc/kernel/ptrace/ptrace-view.c | 21 ---------------------
 arch/powerpc/kernel/ptrace/ptrace.c      |  2 --
 arch/powerpc/kernel/ptrace/ptrace32.c    |  4 ----
 arch/powerpc/kernel/signal_32.c          |  3 ---
 arch/powerpc/kernel/signal_64.c          |  2 --
 arch/powerpc/kernel/traps.c              |  1 -
 arch/powerpc/lib/sstep.c                 |  4 ----
 arch/powerpc/xmon/xmon.c                 | 23 +++++++----------------
 12 files changed, 9 insertions(+), 89 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index c93511bf6b3b..7793d6bd2d7d 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -188,29 +188,16 @@ static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)
 #ifdef __powerpc64__
 #define TRAP_FLAGS_MASK		0x10
 #define TRAP(regs)		((regs)->trap & ~TRAP_FLAGS_MASK)
-#define FULL_REGS(regs)		true
-#define SET_FULL_REGS(regs)	do { } while (0)
-#define CHECK_FULL_REGS(regs)	do { } while (0)
-#define NV_REG_POISON		0xdeadbeefdeadbeefUL
 #else
 /*
- * We use the least-significant bit of the trap field to indicate
- * whether we have saved the full set of registers, or only a
- * partial set.  A 1 there means the partial set.
- * On 4xx we use the next bit to indicate whether the exception
+ * On 4xx we use bit 1 in the trap word to indicate whether the exception
  * is a critical exception (1 means it is).
  */
-#define TRAP_FLAGS_MASK		0x1F
+#define TRAP_FLAGS_MASK		0x1E
 #define TRAP(regs)		((regs)->trap & ~TRAP_FLAGS_MASK)
-#define FULL_REGS(regs)		true
-#define SET_FULL_REGS(regs)	do { } while (0)
 #define IS_CRITICAL_EXC(regs)	(((regs)->trap & 2) != 0)
 #define IS_MCHECK_EXC(regs)	(((regs)->trap & 4) != 0)
 #define IS_DEBUG_EXC(regs)	(((regs)->trap & 8) != 0)
-#define NV_REG_POISON		0xdeadbeef
-#define CHECK_FULL_REGS(regs)						      \
-do {									      \
-} while (0)
 #endif /* __powerpc64__ */
 
 static __always_inline void set_trap(struct pt_regs *regs, unsigned long val)
diff --git a/arch/powerpc/kernel/align.c b/arch/powerpc/kernel/align.c
index a97d5f1a3905..938db36864dd 100644
--- a/arch/powerpc/kernel/align.c
+++ b/arch/powerpc/kernel/align.c
@@ -304,12 +304,6 @@ int fix_alignment(struct pt_regs *regs)
 	struct instruction_op op;
 	int r, type;
 
-	/*
-	 * We require a complete register set, if not, then our assembly
-	 * is broken
-	 */
-	CHECK_FULL_REGS(regs);
-
 	if (is_kernel_addr(regs->nip))
 		r = probe_kernel_read_inst(&instr, (void *)regs->nip);
 	else
diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
index 1b0e1792ac37..b953bb5027e6 100644
--- a/arch/powerpc/kernel/interrupt.c
+++ b/arch/powerpc/kernel/interrupt.c
@@ -51,7 +51,6 @@ notrace long system_call_exception(long r3, long r4, long r5,
 	if (!IS_ENABLED(CONFIG_BOOKE) && !IS_ENABLED(CONFIG_40x))
 		BUG_ON(!(regs->msr & MSR_RI));
 	BUG_ON(!(regs->msr & MSR_PR));
-	BUG_ON(!FULL_REGS(regs));
 	BUG_ON(arch_irq_disabled_regs(regs));
 
 #ifdef CONFIG_PPC_PKEY
@@ -365,7 +364,6 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned
 	if (!IS_ENABLED(CONFIG_BOOKE) && !IS_ENABLED(CONFIG_40x))
 		BUG_ON(!(regs->msr & MSR_RI));
 	BUG_ON(!(regs->msr & MSR_PR));
-	BUG_ON(!FULL_REGS(regs));
 	BUG_ON(arch_irq_disabled_regs(regs));
 	CT_WARN_ON(ct_state() == CONTEXT_USER);
 
@@ -445,7 +443,6 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
 	    unlikely(!(regs->msr & MSR_RI)))
 		unrecoverable_exception(regs);
 	BUG_ON(regs->msr & MSR_PR);
-	BUG_ON(!FULL_REGS(regs));
 	/*
 	 * CT_WARN_ON comes here via program_check_exception,
 	 * so avoid recursion.
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index b966c8e0cead..5269a0d737ed 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1448,11 +1448,9 @@ static void print_msr_bits(unsigned long val)
 #ifdef CONFIG_PPC64
 #define REG		"%016lx"
 #define REGS_PER_LINE	4
-#define LAST_VOLATILE	13
 #else
 #define REG		"%08lx"
 #define REGS_PER_LINE	8
-#define LAST_VOLATILE	12
 #endif
 
 static void __show_regs(struct pt_regs *regs)
@@ -1488,8 +1486,6 @@ static void __show_regs(struct pt_regs *regs)
 		if ((i % REGS_PER_LINE) == 0)
 			pr_cont("\nGPR%02d: ", i);
 		pr_cont(REG " ", regs->gpr[i]);
-		if (i == LAST_VOLATILE && !FULL_REGS(regs))
-			break;
 	}
 	pr_cont("\n");
 	/*
@@ -1692,7 +1688,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	} else {
 		/* user thread */
 		struct pt_regs *regs = current_pt_regs();
-		CHECK_FULL_REGS(regs);
 		*childregs = *regs;
 		if (usp)
 			childregs->gpr[1] = usp;
@@ -1797,13 +1792,6 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
 	regs->ccr = 0;
 	regs->gpr[1] = sp;
 
-	/*
-	 * We have just cleared all the nonvolatile GPRs, so make
-	 * FULL_REGS(regs) return true.  This is necessary to allow
-	 * ptrace to examine the thread immediately after exec.
-	 */
-	SET_FULL_REGS(regs);
-
 #ifdef CONFIG_PPC32
 	regs->mq = 0;
 	regs->nip = start;
diff --git a/arch/powerpc/kernel/ptrace/ptrace-view.c b/arch/powerpc/kernel/ptrace/ptrace-view.c
index 0923c94f684e..48ff9121e9c6 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-view.c
+++ b/arch/powerpc/kernel/ptrace/ptrace-view.c
@@ -221,17 +221,9 @@ static int gpr_get(struct task_struct *target, const struct user_regset *regset,
 #ifdef CONFIG_PPC64
 	struct membuf to_softe = membuf_at(&to, offsetof(struct pt_regs, softe));
 #endif
-	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;
-	}
-
 	membuf_write(&to, target->thread.regs, sizeof(struct user_pt_regs));
 
 	membuf_store(&to_msr, get_user_msr(target));
@@ -252,8 +244,6 @@ static int gpr_set(struct task_struct *target, const struct user_regset *regset,
 	if (target->thread.regs == NULL)
 		return -EIO;
 
-	CHECK_FULL_REGS(target->thread.regs);
-
 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 				 target->thread.regs,
 				 0, PT_MSR * sizeof(reg));
@@ -729,19 +719,9 @@ static int gpr32_get(struct task_struct *target,
 		     const struct user_regset *regset,
 		     struct membuf to)
 {
-	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, to,
 			&target->thread.regs->gpr[0]);
 }
@@ -754,7 +734,6 @@ static int gpr32_set(struct task_struct *target,
 	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]);
 }
diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c
index 51801777906c..0a0a33eb0d28 100644
--- a/arch/powerpc/kernel/ptrace/ptrace.c
+++ b/arch/powerpc/kernel/ptrace/ptrace.c
@@ -59,7 +59,6 @@ long arch_ptrace(struct task_struct *child, long request,
 		if ((addr & (sizeof(long) - 1)) || !child->thread.regs)
 			break;
 
-		CHECK_FULL_REGS(child->thread.regs);
 		if (index < PT_FPR0)
 			ret = ptrace_get_reg(child, (int) index, &tmp);
 		else
@@ -81,7 +80,6 @@ long arch_ptrace(struct task_struct *child, long request,
 		if ((addr & (sizeof(long) - 1)) || !child->thread.regs)
 			break;
 
-		CHECK_FULL_REGS(child->thread.regs);
 		if (index < PT_FPR0)
 			ret = ptrace_put_reg(child, index, data);
 		else
diff --git a/arch/powerpc/kernel/ptrace/ptrace32.c b/arch/powerpc/kernel/ptrace/ptrace32.c
index d30b9ad70edc..19c224808982 100644
--- a/arch/powerpc/kernel/ptrace/ptrace32.c
+++ b/arch/powerpc/kernel/ptrace/ptrace32.c
@@ -83,7 +83,6 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 		if ((addr & 3) || (index > PT_FPSCR32))
 			break;
 
-		CHECK_FULL_REGS(child->thread.regs);
 		if (index < PT_FPR0) {
 			ret = ptrace_get_reg(child, index, &tmp);
 			if (ret)
@@ -133,7 +132,6 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 		if ((addr & 3) || numReg > PT_FPSCR)
 			break;
 
-		CHECK_FULL_REGS(child->thread.regs);
 		if (numReg >= PT_FPR0) {
 			flush_fp_to_thread(child);
 			/* get 64 bit FPR */
@@ -187,7 +185,6 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 		if ((addr & 3) || (index > PT_FPSCR32))
 			break;
 
-		CHECK_FULL_REGS(child->thread.regs);
 		if (index < PT_FPR0) {
 			ret = ptrace_put_reg(child, index, data);
 		} else {
@@ -226,7 +223,6 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 		 */
 		if ((addr & 3) || (numReg > PT_FPSCR))
 			break;
-		CHECK_FULL_REGS(child->thread.regs);
 		if (numReg < PT_FPR0) {
 			unsigned long freg;
 			ret = ptrace_get_reg(child, numReg, &freg);
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index fff4adc5a2b0..94442af383e1 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -94,8 +94,6 @@ __unsafe_save_general_regs(struct pt_regs *regs, struct mcontext __user *frame)
 	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
 	int val, i;
 
-	WARN_ON(!FULL_REGS(regs));
-
 	for (i = 0; i <= PT_RESULT; i ++) {
 		/* Force usr to alway see softe as 1 (interrupts enabled) */
 		if (i == PT_SOFTE)
@@ -147,7 +145,6 @@ failed:
 static __always_inline int
 __unsafe_save_general_regs(struct pt_regs *regs, struct mcontext __user *frame)
 {
-	WARN_ON(!FULL_REGS(regs));
 	unsafe_copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE, failed);
 	return 0;
 
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index e10459f11f8e..dca66481d0c2 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -172,7 +172,6 @@ static long notrace __unsafe_setup_sigcontext(struct sigcontext __user *sc,
 	}
 #endif /* CONFIG_VSX */
 	unsafe_put_user(&sc->gp_regs, &sc->regs, efault_out);
-	WARN_ON(!FULL_REGS(regs));
 	unsafe_copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE, efault_out);
 	unsafe_put_user(msr, &sc->gp_regs[PT_MSR], efault_out);
 	unsafe_put_user(softe, &sc->gp_regs[PT_SOFTE], efault_out);
@@ -309,7 +308,6 @@ static long setup_tm_sigcontexts(struct sigcontext __user *sc,
 
 	err |= __put_user(&sc->gp_regs, &sc->regs);
 	err |= __put_user(&tm_sc->gp_regs, &tm_sc->regs);
-	WARN_ON(!FULL_REGS(regs));
 	err |= __copy_to_user(&tm_sc->gp_regs, regs, GP_REGS_SIZE);
 	err |= __copy_to_user(&sc->gp_regs,
 			      &tsk->thread.ckpt_regs, GP_REGS_SIZE);
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index fd965cbe07d8..2babed7a6a29 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1318,7 +1318,6 @@ static int emulate_instruction(struct pt_regs *regs)
 
 	if (!user_mode(regs))
 		return -EINVAL;
-	CHECK_FULL_REGS(regs);
 
 	if (get_user(instword, (u32 __user *)(regs->nip)))
 		return -EFAULT;
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 739ea6dc461c..45bda2520755 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -1401,10 +1401,6 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
 		break;
 	}
 
-	/* Following cases refer to regs->gpr[], so we need all regs */
-	if (!FULL_REGS(regs))
-		return -1;
-
 	rd = (word >> 21) & 0x1f;
 	ra = (word >> 16) & 0x1f;
 	rb = (word >> 11) & 0x1f;
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 2e94647c8711..361534f67082 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -1815,25 +1815,16 @@ static void prregs(struct pt_regs *fp)
 	}
 
 #ifdef CONFIG_PPC64
-	if (FULL_REGS(fp)) {
-		for (n = 0; n < 16; ++n)
-			printf("R%.2d = "REG"   R%.2d = "REG"\n",
-			       n, fp->gpr[n], n+16, fp->gpr[n+16]);
-	} else {
-		for (n = 0; n < 7; ++n)
-			printf("R%.2d = "REG"   R%.2d = "REG"\n",
-			       n, fp->gpr[n], n+7, fp->gpr[n+7]);
-	}
+#define R_PER_LINE 2
 #else
+#define R_PER_LINE 4
+#endif
+
 	for (n = 0; n < 32; ++n) {
-		printf("R%.2d = %.8lx%s", n, fp->gpr[n],
-		       (n & 3) == 3? "\n": "   ");
-		if (n == 12 && !FULL_REGS(fp)) {
-			printf("\n");
-			break;
-		}
+		printf("R%.2d = "REG"%s", n, fp->gpr[n],
+			(n % R_PER_LINE) == R_PER_LINE - 1 ? "\n" : "   ");
 	}
-#endif
+
 	printf("pc  = ");
 	xmon_print_symbol(fp->nip, " ", "\n");
 	if (!trap_is_syscall(fp) && cpu_has_feature(CPU_FTR_CFAR)) {
-- 
cgit 


From 5256426247837feb8703625bda7fcfc824af04cf Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@csgroup.eu>
Date: Fri, 23 Apr 2021 13:52:10 +0000
Subject: powerpc/signal32: Fix erroneous SIGSEGV on RT signal return

Return of user_read_access_begin() is tested the wrong way,
leading to a SIGSEGV when the user address is valid and likely
an Oops when the user address is bad.

Fix the test.

Fixes: 887f3ceb51cd ("powerpc/signal32: Convert do_setcontext[_tm]() to user access block")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a29aadc54c93bcbf069a83615fa102ca0f59c3ae.1619185912.git.christophe.leroy@csgroup.eu
---
 arch/powerpc/kernel/signal_32.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'arch/powerpc/kernel/signal_32.c')

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 94442af383e1..915ea2a457a0 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -971,7 +971,7 @@ static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int
 	sigset_t set;
 	struct mcontext __user *mcp;
 
-	if (user_read_access_begin(ucp, sizeof(*ucp)))
+	if (!user_read_access_begin(ucp, sizeof(*ucp)))
 		return -EFAULT;
 
 	unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
@@ -1009,7 +1009,7 @@ static int do_setcontext_tm(struct ucontext __user *ucp,
 	u32 cmcp;
 	u32 tm_cmcp;
 
-	if (user_read_access_begin(ucp, sizeof(*ucp)))
+	if (!user_read_access_begin(ucp, sizeof(*ucp)))
 		return -EFAULT;
 
 	unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
-- 
cgit