[PATCH 02/24] ptrace: Add compat PTRACE_{G,S}ETSIGMASK handlers

[Yury Norov]

From: James Morse 

compat_ptrace_request() lacks handlers for PTRACE_{G,S}ETSIGMASK,
instead using those in ptrace_request(). The compat variant should
read a compat_sigset_t from userspace instead of ptrace_request()s
sigset_t.

While compat_sigset_t is the same size as sigset_t, it is defined as
2xu32, instead of a single u64. On a big-endian CPU this means that
compat_sigset_t is passed to user-space using middle-endianness,
where the least-significant u32 is written most significant byte
first.

If ptrace_request()s code is used userspace will read the most
significant u32 where it expected the least significant.

Instead of duplicating ptrace_request()s code as a special case in
the arch code, handle it here.

Fixes: 29000caecbe87 ("ptrace: add ability to get/set signal-blocked mask")
CC: Andrey Vagin 
Signed-off-by: James Morse 

Yury:
Replace sigset_{to,from}_compat() with new {get,put}_compat_sigset()
Signed-off-by: Yury Norov 
---
 kernel/ptrace.c | 48 
 1 file changed, 36 insertions(+), 12 deletions(-)

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 21fec73d45d4..214944d7c268 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -880,6 +880,22 @@ static int ptrace_regset(struct task_struct *task, int 
req, unsigned int type,
 EXPORT_SYMBOL_GPL(task_user_regset_view);
 #endif
 
+static int ptrace_setsigmask(struct task_struct *child, sigset_t *new_set)
+{
+   sigdelsetmask(new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+   /*
+* Every thread does recalc_sigpending() after resume, so
+* retarget_shared_pending() and recalc_sigpending() are not
+* called here.
+*/
+   spin_lock_irq(>sighand->siglock);
+   child->blocked = *new_set;
+   spin_unlock_irq(>sighand->siglock);
+
+   return 0;
+}
+
 int ptrace_request(struct task_struct *child, long request,
   unsigned long addr, unsigned long data)
 {
@@ -951,18 +967,7 @@ int ptrace_request(struct task_struct *child, long request,
break;
}
 
-   sigdelsetmask(_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
-
-   /*
-* Every thread does recalc_sigpending() after resume, so
-* retarget_shared_pending() and recalc_sigpending() are not
-* called here.
-*/
-   spin_lock_irq(>sighand->siglock);
-   child->blocked = new_set;
-   spin_unlock_irq(>sighand->siglock);
-
-   ret = 0;
+   ret = ptrace_setsigmask(child, _set);
break;
}
 
@@ -1181,6 +1186,7 @@ int compat_ptrace_request(struct task_struct *child, 
compat_long_t request,
 {
compat_ulong_t __user *datap = compat_ptr(data);
compat_ulong_t word;
+   sigset_t new_set;
siginfo_t siginfo;
int ret;
 
@@ -1221,6 +1227,24 @@ int compat_ptrace_request(struct task_struct *child, 
compat_long_t request,
else
ret = ptrace_setsiginfo(child, );
break;
+   case PTRACE_GETSIGMASK:
+   if (addr != sizeof(compat_sigset_t))
+   return -EINVAL;
+
+   ret = put_compat_sigset((compat_sigset_t __user *) datap,
+   >blocked, sizeof(compat_sigset_t));
+   break;
+   case PTRACE_SETSIGMASK:
+   if (addr != sizeof(compat_sigset_t))
+   return -EINVAL;
+
+   ret = get_compat_sigset(_set,
+   (compat_sigset_t __user *) datap);
+   if (ret)
+   break;
+
+   ret = ptrace_setsigmask(child, _set);
+   break;
 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
case PTRACE_GETREGSET:
case PTRACE_SETREGSET:
-- 
2.17.0

[PATCH 02/24] ptrace: Add compat PTRACE_{G,S}ETSIGMASK handlers

[Yury Norov]

From: James Morse 

compat_ptrace_request() lacks handlers for PTRACE_{G,S}ETSIGMASK,
instead using those in ptrace_request(). The compat variant should
read a compat_sigset_t from userspace instead of ptrace_request()s
sigset_t.

While compat_sigset_t is the same size as sigset_t, it is defined as
2xu32, instead of a single u64. On a big-endian CPU this means that
compat_sigset_t is passed to user-space using middle-endianness,
where the least-significant u32 is written most significant byte
first.

If ptrace_request()s code is used userspace will read the most
significant u32 where it expected the least significant.

Instead of duplicating ptrace_request()s code as a special case in
the arch code, handle it here.

Fixes: 29000caecbe87 ("ptrace: add ability to get/set signal-blocked mask")
CC: Andrey Vagin 
Signed-off-by: James Morse 

Yury:
Replace sigset_{to,from}_compat() with new {get,put}_compat_sigset()
Signed-off-by: Yury Norov 
---
 kernel/ptrace.c | 48 
 1 file changed, 36 insertions(+), 12 deletions(-)

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 21fec73d45d4..214944d7c268 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -880,6 +880,22 @@ static int ptrace_regset(struct task_struct *task, int 
req, unsigned int type,
 EXPORT_SYMBOL_GPL(task_user_regset_view);
 #endif
 
+static int ptrace_setsigmask(struct task_struct *child, sigset_t *new_set)
+{
+   sigdelsetmask(new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+   /*
+* Every thread does recalc_sigpending() after resume, so
+* retarget_shared_pending() and recalc_sigpending() are not
+* called here.
+*/
+   spin_lock_irq(>sighand->siglock);
+   child->blocked = *new_set;
+   spin_unlock_irq(>sighand->siglock);
+
+   return 0;
+}
+
 int ptrace_request(struct task_struct *child, long request,
   unsigned long addr, unsigned long data)
 {
@@ -951,18 +967,7 @@ int ptrace_request(struct task_struct *child, long request,
break;
}
 
-   sigdelsetmask(_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
-
-   /*
-* Every thread does recalc_sigpending() after resume, so
-* retarget_shared_pending() and recalc_sigpending() are not
-* called here.
-*/
-   spin_lock_irq(>sighand->siglock);
-   child->blocked = new_set;
-   spin_unlock_irq(>sighand->siglock);
-
-   ret = 0;
+   ret = ptrace_setsigmask(child, _set);
break;
}
 
@@ -1181,6 +1186,7 @@ int compat_ptrace_request(struct task_struct *child, 
compat_long_t request,
 {
compat_ulong_t __user *datap = compat_ptr(data);
compat_ulong_t word;
+   sigset_t new_set;
siginfo_t siginfo;
int ret;
 
@@ -1221,6 +1227,24 @@ int compat_ptrace_request(struct task_struct *child, 
compat_long_t request,
else
ret = ptrace_setsiginfo(child, );
break;
+   case PTRACE_GETSIGMASK:
+   if (addr != sizeof(compat_sigset_t))
+   return -EINVAL;
+
+   ret = put_compat_sigset((compat_sigset_t __user *) datap,
+   >blocked, sizeof(compat_sigset_t));
+   break;
+   case PTRACE_SETSIGMASK:
+   if (addr != sizeof(compat_sigset_t))
+   return -EINVAL;
+
+   ret = get_compat_sigset(_set,
+   (compat_sigset_t __user *) datap);
+   if (ret)
+   break;
+
+   ret = ptrace_setsigmask(child, _set);
+   break;
 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
case PTRACE_GETREGSET:
case PTRACE_SETREGSET:
-- 
2.17.0

[PATCH 02/24] ptrace: Add compat PTRACE_{G,S}ETSIGMASK handlers

[Yury Norov]

From: James Morse 

compat_ptrace_request() lacks handlers for PTRACE_{G,S}ETSIGMASK,
instead using those in ptrace_request(). The compat variant should
read a compat_sigset_t from userspace instead of ptrace_request()s
sigset_t.

While compat_sigset_t is the same size as sigset_t, it is defined as
2xu32, instead of a single u64. On a big-endian CPU this means that
compat_sigset_t is passed to user-space using middle-endianness,
where the least-significant u32 is written most significant byte
first.

If ptrace_request()s code is used userspace will read the most
significant u32 where it expected the least significant.

Instead of duplicating ptrace_request()s code as a special case in
the arch code, handle it here.

Fixes: 29000caecbe87 ("ptrace: add ability to get/set signal-blocked mask")
CC: Andrey Vagin 
Reported-by: Zhou Chengming 
Signed-off-by: James Morse 

Yury:
Replace sigset_{to,from}_compat() with new {get,put}_compat_sigset()
Signed-off-by: Yury Norov 
---
 kernel/ptrace.c | 48 
 1 file changed, 36 insertions(+), 12 deletions(-)

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 21fec73d45d4..214944d7c268 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -880,6 +880,22 @@ static int ptrace_regset(struct task_struct *task, int 
req, unsigned int type,
 EXPORT_SYMBOL_GPL(task_user_regset_view);
 #endif
 
+static int ptrace_setsigmask(struct task_struct *child, sigset_t *new_set)
+{
+   sigdelsetmask(new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+   /*
+* Every thread does recalc_sigpending() after resume, so
+* retarget_shared_pending() and recalc_sigpending() are not
+* called here.
+*/
+   spin_lock_irq(>sighand->siglock);
+   child->blocked = *new_set;
+   spin_unlock_irq(>sighand->siglock);
+
+   return 0;
+}
+
 int ptrace_request(struct task_struct *child, long request,
   unsigned long addr, unsigned long data)
 {
@@ -951,18 +967,7 @@ int ptrace_request(struct task_struct *child, long request,
break;
}
 
-   sigdelsetmask(_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
-
-   /*
-* Every thread does recalc_sigpending() after resume, so
-* retarget_shared_pending() and recalc_sigpending() are not
-* called here.
-*/
-   spin_lock_irq(>sighand->siglock);
-   child->blocked = new_set;
-   spin_unlock_irq(>sighand->siglock);
-
-   ret = 0;
+   ret = ptrace_setsigmask(child, _set);
break;
}
 
@@ -1181,6 +1186,7 @@ int compat_ptrace_request(struct task_struct *child, 
compat_long_t request,
 {
compat_ulong_t __user *datap = compat_ptr(data);
compat_ulong_t word;
+   sigset_t new_set;
siginfo_t siginfo;
int ret;
 
@@ -1221,6 +1227,24 @@ int compat_ptrace_request(struct task_struct *child, 
compat_long_t request,
else
ret = ptrace_setsiginfo(child, );
break;
+   case PTRACE_GETSIGMASK:
+   if (addr != sizeof(compat_sigset_t))
+   return -EINVAL;
+
+   ret = put_compat_sigset((compat_sigset_t __user *) datap,
+   >blocked, sizeof(compat_sigset_t));
+   break;
+   case PTRACE_SETSIGMASK:
+   if (addr != sizeof(compat_sigset_t))
+   return -EINVAL;
+
+   ret = get_compat_sigset(_set,
+   (compat_sigset_t __user *) datap);
+   if (ret)
+   break;
+
+   ret = ptrace_setsigmask(child, _set);
+   break;
 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
case PTRACE_GETREGSET:
case PTRACE_SETREGSET:
-- 
2.17.0

[PATCH 02/24] ptrace: Add compat PTRACE_{G,S}ETSIGMASK handlers

[Yury Norov]

From: James Morse 

compat_ptrace_request() lacks handlers for PTRACE_{G,S}ETSIGMASK,
instead using those in ptrace_request(). The compat variant should
read a compat_sigset_t from userspace instead of ptrace_request()s
sigset_t.

While compat_sigset_t is the same size as sigset_t, it is defined as
2xu32, instead of a single u64. On a big-endian CPU this means that
compat_sigset_t is passed to user-space using middle-endianness,
where the least-significant u32 is written most significant byte
first.

If ptrace_request()s code is used userspace will read the most
significant u32 where it expected the least significant.

Instead of duplicating ptrace_request()s code as a special case in
the arch code, handle it here.

Fixes: 29000caecbe87 ("ptrace: add ability to get/set signal-blocked mask")
CC: Andrey Vagin 
Reported-by: Zhou Chengming 
Signed-off-by: James Morse 

Yury:
Replace sigset_{to,from}_compat() with new {get,put}_compat_sigset()
Signed-off-by: Yury Norov 
---
 kernel/ptrace.c | 48 
 1 file changed, 36 insertions(+), 12 deletions(-)

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 21fec73d45d4..214944d7c268 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -880,6 +880,22 @@ static int ptrace_regset(struct task_struct *task, int 
req, unsigned int type,
 EXPORT_SYMBOL_GPL(task_user_regset_view);
 #endif
 
+static int ptrace_setsigmask(struct task_struct *child, sigset_t *new_set)
+{
+   sigdelsetmask(new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+   /*
+* Every thread does recalc_sigpending() after resume, so
+* retarget_shared_pending() and recalc_sigpending() are not
+* called here.
+*/
+   spin_lock_irq(>sighand->siglock);
+   child->blocked = *new_set;
+   spin_unlock_irq(>sighand->siglock);
+
+   return 0;
+}
+
 int ptrace_request(struct task_struct *child, long request,
   unsigned long addr, unsigned long data)
 {
@@ -951,18 +967,7 @@ int ptrace_request(struct task_struct *child, long request,
break;
}
 
-   sigdelsetmask(_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
-
-   /*
-* Every thread does recalc_sigpending() after resume, so
-* retarget_shared_pending() and recalc_sigpending() are not
-* called here.
-*/
-   spin_lock_irq(>sighand->siglock);
-   child->blocked = new_set;
-   spin_unlock_irq(>sighand->siglock);
-
-   ret = 0;
+   ret = ptrace_setsigmask(child, _set);
break;
}
 
@@ -1181,6 +1186,7 @@ int compat_ptrace_request(struct task_struct *child, 
compat_long_t request,
 {
compat_ulong_t __user *datap = compat_ptr(data);
compat_ulong_t word;
+   sigset_t new_set;
siginfo_t siginfo;
int ret;
 
@@ -1221,6 +1227,24 @@ int compat_ptrace_request(struct task_struct *child, 
compat_long_t request,
else
ret = ptrace_setsiginfo(child, );
break;
+   case PTRACE_GETSIGMASK:
+   if (addr != sizeof(compat_sigset_t))
+   return -EINVAL;
+
+   ret = put_compat_sigset((compat_sigset_t __user *) datap,
+   >blocked, sizeof(compat_sigset_t));
+   break;
+   case PTRACE_SETSIGMASK:
+   if (addr != sizeof(compat_sigset_t))
+   return -EINVAL;
+
+   ret = get_compat_sigset(_set,
+   (compat_sigset_t __user *) datap);
+   if (ret)
+   break;
+
+   ret = ptrace_setsigmask(child, _set);
+   break;
 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
case PTRACE_GETREGSET:
case PTRACE_SETREGSET:
-- 
2.17.0