Merge remote-tracking branch 'remotes/vivier2/tags/linux-user-for-5.2-pull-request' into staging

Fixes for epoll_ctl and stack_t

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* remotes/vivier2/tags/linux-user-for-5.2-pull-request:
  linux-user: Prevent crash in epoll_ctl
  linux-user: Correct definition of stack_t

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

16 files changed, 56 insertions, 49 deletions

diff --git a/linux-user/alpha/target_signal.h b/linux-user/alpha/target_signal.h
index cd63d59fde..b83797281c 100644
--- a/linux-user/alpha/target_signal.h
+++ b/linux-user/alpha/target_signal.h
@@ -42,8 +42,7 @@
 
 typedef struct target_sigaltstack {
     abi_ulong ss_sp;
-    int32_t ss_flags;
-    int32_t dummy;
+    abi_int ss_flags;
     abi_ulong ss_size;
 } target_stack_t;
 
diff --git a/linux-user/arm/target_signal.h b/linux-user/arm/target_signal.h
index ea123c40f3..0998dd6dfa 100644
--- a/linux-user/arm/target_signal.h
+++ b/linux-user/arm/target_signal.h
@@ -4,9 +4,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	abi_long ss_flags;
-	abi_ulong ss_size;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;
 
 
diff --git a/linux-user/cris/target_signal.h b/linux-user/cris/target_signal.h
index 1cb5548f85..495a142896 100644
--- a/linux-user/cris/target_signal.h
+++ b/linux-user/cris/target_signal.h
@@ -4,9 +4,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	abi_ulong ss_size;
-	abi_long ss_flags;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;
 
 
diff --git a/linux-user/hppa/target_signal.h b/linux-user/hppa/target_signal.h
index c2a0102ed7..c52a3ea579 100644
--- a/linux-user/hppa/target_signal.h
+++ b/linux-user/hppa/target_signal.h
@@ -44,7 +44,7 @@
 
 typedef struct target_sigaltstack {
     abi_ulong ss_sp;
-    int32_t ss_flags;
+    abi_int ss_flags;
     abi_ulong ss_size;
 } target_stack_t;
 
diff --git a/linux-user/i386/target_signal.h b/linux-user/i386/target_signal.h
index f55e78fd33..50361af874 100644
--- a/linux-user/i386/target_signal.h
+++ b/linux-user/i386/target_signal.h
@@ -4,9 +4,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	abi_long ss_flags;
-	abi_ulong ss_size;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;
 
 
diff --git a/linux-user/m68k/target_signal.h b/linux-user/m68k/target_signal.h
index 314e808844..d096544ef8 100644
--- a/linux-user/m68k/target_signal.h
+++ b/linux-user/m68k/target_signal.h
@@ -4,9 +4,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	abi_long ss_flags;
-	abi_ulong ss_size;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;
 
 
diff --git a/linux-user/microblaze/target_signal.h b/linux-user/microblaze/target_signal.h
index 08bcf24b9d..1c326296de 100644
--- a/linux-user/microblaze/target_signal.h
+++ b/linux-user/microblaze/target_signal.h
@@ -4,9 +4,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	abi_ulong ss_size;
-	abi_long ss_flags;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;
 
 
diff --git a/linux-user/mips/target_signal.h b/linux-user/mips/target_signal.h
index 66e1ad44a6..fa4084a99d 100644
--- a/linux-user/mips/target_signal.h
+++ b/linux-user/mips/target_signal.h
@@ -45,9 +45,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_long ss_sp;
-	abi_ulong ss_size;
-	abi_long ss_flags;
+    abi_ulong ss_sp;
+    abi_ulong ss_size;
+    abi_int ss_flags;
 } target_stack_t;
 
 
diff --git a/linux-user/mips64/target_signal.h b/linux-user/mips64/target_signal.h
index 753e91fbd6..799f7a668c 100644
--- a/linux-user/mips64/target_signal.h
+++ b/linux-user/mips64/target_signal.h
@@ -45,12 +45,11 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_long ss_sp;
-	abi_ulong ss_size;
-	abi_int ss_flags;
+    abi_ulong ss_sp;
+    abi_ulong ss_size;
+    abi_int ss_flags;
 } target_stack_t;
 
-
 /*
  * sigaltstack controls
  */
diff --git a/linux-user/nios2/target_signal.h b/linux-user/nios2/target_signal.h
index fe48721b3d..aebf749f12 100644
--- a/linux-user/nios2/target_signal.h
+++ b/linux-user/nios2/target_signal.h
@@ -4,11 +4,12 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-    abi_long ss_sp;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
     abi_ulong ss_size;
-    abi_long ss_flags;
 } target_stack_t;
 
+
 /* sigaltstack controls  */
 #define TARGET_SS_ONSTACK     1
 #define TARGET_SS_DISABLE     2
diff --git a/linux-user/ppc/target_signal.h b/linux-user/ppc/target_signal.h
index 4453e2e7ef..72fcdd9bfa 100644
--- a/linux-user/ppc/target_signal.h
+++ b/linux-user/ppc/target_signal.h
@@ -4,9 +4,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	int ss_flags;
-	abi_ulong ss_size;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;
 
 
diff --git a/linux-user/s390x/target_signal.h b/linux-user/s390x/target_signal.h
index b58bc7c20f..bbfc464d44 100644
--- a/linux-user/s390x/target_signal.h
+++ b/linux-user/s390x/target_signal.h
@@ -3,7 +3,7 @@
 
 typedef struct target_sigaltstack {
     abi_ulong ss_sp;
-    int ss_flags;
+    abi_int ss_flags;
     abi_ulong ss_size;
 } target_stack_t;
 
diff --git a/linux-user/sh4/target_signal.h b/linux-user/sh4/target_signal.h
index 434970a990..d7309b7136 100644
--- a/linux-user/sh4/target_signal.h
+++ b/linux-user/sh4/target_signal.h
@@ -4,9 +4,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	abi_long ss_flags;
-	abi_ulong ss_size;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;
 
 
diff --git a/linux-user/sparc/target_signal.h b/linux-user/sparc/target_signal.h
index 5cc40327d2..1b10d1490f 100644
--- a/linux-user/sparc/target_signal.h
+++ b/linux-user/sparc/target_signal.h
@@ -42,9 +42,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	abi_long ss_flags;
-	abi_ulong ss_size;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;
 
 
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 3160a9ba06..27adee908e 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -12590,17 +12590,25 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         struct epoll_event ep;
         struct epoll_event *epp = 0;
         if (arg4) {
-            struct target_epoll_event *target_ep;
-            if (!lock_user_struct(VERIFY_READ, target_ep, arg4, 1)) {
-                return -TARGET_EFAULT;
+            if (arg2 != EPOLL_CTL_DEL) {
+                struct target_epoll_event *target_ep;
+                if (!lock_user_struct(VERIFY_READ, target_ep, arg4, 1)) {
+                    return -TARGET_EFAULT;
+                }
+                ep.events = tswap32(target_ep->events);
+                /*
+                 * The epoll_data_t union is just opaque data to the kernel,
+                 * so we transfer all 64 bits across and need not worry what
+                 * actual data type it is.
+                 */
+                ep.data.u64 = tswap64(target_ep->data.u64);
+                unlock_user_struct(target_ep, arg4, 0);
             }
-            ep.events = tswap32(target_ep->events);
-            /* The epoll_data_t union is just opaque data to the kernel,
-             * so we transfer all 64 bits across and need not worry what
-             * actual data type it is.
+            /*
+             * before kernel 2.6.9, EPOLL_CTL_DEL operation required a
+             * non-null pointer, even though this argument is ignored.
+             *
              */
-            ep.data.u64 = tswap64(target_ep->data.u64);
-            unlock_user_struct(target_ep, arg4, 0);
             epp = &ep;
         }
         return get_errno(epoll_ctl(arg1, arg2, arg3, epp));
diff --git a/linux-user/x86_64/target_signal.h b/linux-user/x86_64/target_signal.h
index 4c4380f7b9..4ea74f20dd 100644
--- a/linux-user/x86_64/target_signal.h
+++ b/linux-user/x86_64/target_signal.h
@@ -4,9 +4,9 @@
 /* this struct defines a stack used during syscall handling */
 
 typedef struct target_sigaltstack {
-	abi_ulong ss_sp;
-	abi_long ss_flags;
-	abi_ulong ss_size;
+    abi_ulong ss_sp;
+    abi_int ss_flags;
+    abi_ulong ss_size;
 } target_stack_t;