From: Dmitry V. Levin <ldv@altlinux.org>
Date: Mon, 19 Dec 2016 12:05:31 +0000 (+0000)
Subject: struct tcb: make types of syscall arguments unsigned
X-Git-Tag: v4.16~336
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=fc346f1d9125ad7fdda748923ac733f4f00fd272;p=strace

struct tcb: make types of syscall arguments unsigned

This is the first step in the direction of revisiting current practice
of indiscriminate use of signed types for syscall arguments and memory
addresses.

* kernel_types.h (kernel_ureg_t): New type, typedef to unsigned long.
* defs.h (struct tcb): Change type of u_arg from long to kernel_ureg_t.
[HAVE_STRUCT_TCB_EXT_ARG]: Change type of ext_arg from long long
to unsigned long long.
* desc.c (decode_select): Change type of syscall arguments from long
to kernel_ureg_t.
(SYS_FUNC(oldselect)): Change type of select_args from long
to kernel_ureg_t.
* io.c (print_lld_from_low_high_val): Remove no longer needed cast
of syscall arguments to unsigned long.
* lseek.c (SYS_FUNC(lseek)): Cast syscall argument from unsigned long
to long.
* mem.c (print_mmap): Change type of syscall arguments from long
to kernel_ureg_t.
(SYS_FUNC(old_mmap), SYS_FUNC(old_mmap_pgoff)): Change type of u_arg
from long to kernel_ureg_t.
(SYS_FUNC(mmap), SYS_FUNC(mmap_pgoff), SYS_FUNC(mmap_pgoff)): Remove
no longer needed cast of syscall arguments to unsigned long.
* pathtrace.c (pathtrace_match): Change type of args and select_args
from long to kernel_ureg_t.
* util.c (getarg_ull): Remove no longer needed casts of syscall
arguments to unsigned types.
---

diff --git a/defs.h b/defs.h
index 09af8d08..8232d3cf 100644
--- a/defs.h
+++ b/defs.h
@@ -230,9 +230,9 @@ struct tcb {
 	int qual_flg;		/* qual_flags[scno] or DEFAULT_QUAL_FLAGS + RAW */
 	unsigned long u_error;	/* Error code */
 	kernel_scno_t scno;	/* System call number */
-	long u_arg[MAX_ARGS];	/* System call arguments */
+	kernel_ureg_t u_arg[MAX_ARGS];	/* System call arguments */
 #if HAVE_STRUCT_TCB_EXT_ARG
-	long long ext_arg[MAX_ARGS];
+	unsigned long long ext_arg[MAX_ARGS];
 	long long u_lrval;	/* long long return value */
 #endif
 	long u_rval;		/* Return value */
diff --git a/desc.c b/desc.c
index 4add78e7..dc47a7f0 100644
--- a/desc.c
+++ b/desc.c
@@ -69,7 +69,7 @@ SYS_FUNC(dup3)
 }
 
 static int
-decode_select(struct tcb *tcp, long *args,
+decode_select(struct tcb *tcp, kernel_ureg_t *args,
 	      void (*print_tv_ts) (struct tcb *, const long),
 	      const char * (*sprint_tv_ts) (struct tcb *, const long))
 {
@@ -192,7 +192,7 @@ decode_select(struct tcb *tcp, long *args,
 
 SYS_FUNC(oldselect)
 {
-	long select_args[5];
+	kernel_ureg_t select_args[5];
 	unsigned int oldselect_args[5];
 
 	if (sizeof(*select_args) == sizeof(*oldselect_args)) {
diff --git a/io.c b/io.c
index 45c553e0..3d2425b9 100644
--- a/io.c
+++ b/io.c
@@ -194,9 +194,8 @@ print_lld_from_low_high_val(struct tcb *tcp, int arg)
 		tprintf("%ld", tcp->u_arg[arg]);
 # if SUPPORTED_PERSONALITIES > 1
 	else
-		tprintf("%ld",
-			((unsigned long) tcp->u_arg[arg + 1] << current_wordsize * 8)
-			| (unsigned long) tcp->u_arg[arg]);
+		tprintf("%ld", (tcp->u_arg[arg + 1] << current_wordsize * 8)
+			       | tcp->u_arg[arg]);
 # endif
 #elif SIZEOF_LONG > 4
 # error Unsupported configuration: SIZEOF_LONG > 4 && SIZEOF_LONG_LONG > SIZEOF_LONG
diff --git a/kernel_types.h b/kernel_types.h
index 60cb629e..c54af74e 100644
--- a/kernel_types.h
+++ b/kernel_types.h
@@ -48,6 +48,7 @@ typedef unsigned long kernel_ulong_t;
 # endif
 
 typedef unsigned long kernel_scno_t;
+typedef unsigned long kernel_ureg_t;
 
 typedef struct {
 	kernel_ulong_t	d_ino;
diff --git a/lseek.c b/lseek.c
index 1846abe4..708250cf 100644
--- a/lseek.c
+++ b/lseek.c
@@ -53,7 +53,7 @@ SYS_FUNC(lseek)
 # if SUPPORTED_PERSONALITIES > 1
 	/* tcp->ext_arg is not initialized for compat personality */
 	if (current_personality == 1) {
-		offset = tcp->u_arg[1];
+		offset = (long) tcp->u_arg[1];
 	} else
 # endif
 	{
@@ -75,10 +75,10 @@ SYS_FUNC(lseek)
 # if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
 #  ifdef X86_64
 		current_personality == 1 ?
-			(long)(int) tcp->u_arg[1] : tcp->u_arg[1];
+			(long) (int) tcp->u_arg[1] : (long) tcp->u_arg[1];
 #  else
 		current_wordsize == 4 ?
-			(long)(int) tcp->u_arg[1] : tcp->u_arg[1];
+			(long) (int) tcp->u_arg[1] : (long) tcp->u_arg[1];
 #  endif
 # else
 		tcp->u_arg[1];
diff --git a/mem.c b/mem.c
index 453a64e3..437b8ea5 100644
--- a/mem.c
+++ b/mem.c
@@ -55,7 +55,7 @@ SYS_FUNC(brk)
 #include "xlat/mmap_flags.h"
 
 static void
-print_mmap(struct tcb *tcp, long *u_arg, unsigned long long offset)
+print_mmap(struct tcb *tcp, kernel_ureg_t *u_arg, unsigned long long offset)
 {
 	const unsigned long addr = u_arg[0];
 	const unsigned long len = u_arg[1];
@@ -93,7 +93,7 @@ print_mmap(struct tcb *tcp, long *u_arg, unsigned long long offset)
 /* Params are pointed to by u_arg[0], offset is in bytes */
 SYS_FUNC(old_mmap)
 {
-	long u_arg[6];
+	kernel_ureg_t u_arg[6];
 # if defined AARCH64 || defined X86_64
 	/* We are here only in a 32-bit personality. */
 	unsigned int narrow_arg[6];
@@ -116,7 +116,7 @@ SYS_FUNC(old_mmap)
 /* Params are pointed to by u_arg[0], offset is in pages */
 SYS_FUNC(old_mmap_pgoff)
 {
-	long u_arg[5];
+	kernel_ureg_t u_arg[5];
 	int i;
 	unsigned narrow_arg[6];
 	unsigned long long offset;
@@ -139,7 +139,7 @@ SYS_FUNC(mmap)
 #if HAVE_STRUCT_TCB_EXT_ARG
 		tcp->ext_arg[5];	/* try test/x32_mmap.c */
 #else
-		(unsigned long) tcp->u_arg[5];
+		tcp->u_arg[5];
 #endif
 	/* Example of kernel-side handling of this variety of mmap:
 	 * arch/x86/kernel/sys_x86_64.c::SYSCALL_DEFINE6(mmap, ...) calls
@@ -156,7 +156,7 @@ SYS_FUNC(mmap_pgoff)
 {
 	/* Try test/mmap_offset_decode.c */
 	unsigned long long offset;
-	offset = (unsigned long) tcp->u_arg[5];
+	offset = tcp->u_arg[5];
 	offset *= get_pagesize();
 	print_mmap(tcp, tcp->u_arg, offset);
 
@@ -167,7 +167,7 @@ SYS_FUNC(mmap_pgoff)
 SYS_FUNC(mmap_4koff)
 {
 	unsigned long long offset;
-	offset = (unsigned long) tcp->u_arg[5];
+	offset = tcp->u_arg[5];
 	offset <<= 12;
 	print_mmap(tcp, tcp->u_arg, offset);
 
diff --git a/pathtrace.c b/pathtrace.c
index 8f7ea749..0dbf55dc 100644
--- a/pathtrace.c
+++ b/pathtrace.c
@@ -248,8 +248,8 @@ pathtrace_match(struct tcb *tcp)
 	{
 		int     i, j;
 		int     nfds;
-		long   *args;
-		long    select_args[5];
+		kernel_ureg_t *args;
+		kernel_ureg_t select_args[5];
 		unsigned int oldselect_args[5];
 		unsigned int fdsize;
 		fd_set *fds;
diff --git a/util.c b/util.c
index 289e59d3..d7d7c047 100644
--- a/util.c
+++ b/util.c
@@ -1511,12 +1511,12 @@ getarg_ull(struct tcb *tcp, int argn)
 #if HAVE_STRUCT_TCB_EXT_ARG
 # if SUPPORTED_PERSONALITIES > 1
 	if (current_personality == 1)
-		return (unsigned long) tcp->u_arg[argn];
+		return tcp->u_arg[argn];
 	else
 # endif
-	return (unsigned long long) tcp->ext_arg[argn];
+	return tcp->ext_arg[argn];
 #else
-	return (unsigned long) tcp->u_arg[argn];
+	return tcp->u_arg[argn];
 #endif
 }