From c7887325230aec47d47a32562a6e26014a0fafca Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 11 Aug 2010 11:26:22 +0100 Subject: Mark arguments to certain syscalls as being const Mark arguments to certain system calls as being const where they should be but aren't. The list includes: (*) The filename arguments of various stat syscalls, execve(), various utimes syscalls and some mount syscalls. (*) The filename arguments of some syscall helpers relating to the above. (*) The buffer argument of various write syscalls. Signed-off-by: David Howells Acked-by: David S. Miller Signed-off-by: Linus Torvalds --- arch/m68k/kernel/process.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/m68k/kernel') diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c index 1a6be27cf16..221d0b71ce3 100644 --- a/arch/m68k/kernel/process.c +++ b/arch/m68k/kernel/process.c @@ -315,7 +315,7 @@ EXPORT_SYMBOL(dump_fpu); /* * sys_execve() executes a new program. */ -asmlinkage int sys_execve(char __user *name, char __user * __user *argv, char __user * __user *envp) +asmlinkage int sys_execve(const char __user *name, char __user * __user *argv, char __user * __user *envp) { int error; char * filename; -- cgit v1.2.3-18-g5258 From d7627467b7a8dd6944885290a03a07ceb28c10eb Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 17 Aug 2010 23:52:56 +0100 Subject: Make do_execve() take a const filename pointer Make do_execve() take a const filename pointer so that kernel_execve() compiles correctly on ARM: arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type This also requires the argv and envp arguments to be consted twice, once for the pointer array and once for the strings the array points to. This is because do_execve() passes a pointer to the filename (now const) to copy_strings_kernel(). A simpler alternative would be to cast the filename pointer in do_execve() when it's passed to copy_strings_kernel(). do_execve() may not change any of the strings it is passed as part of the argv or envp lists as they are some of them in .rodata, so marking these strings as const should be fine. Further kernel_execve() and sys_execve() need to be changed to match. This has been test built on x86_64, frv, arm and mips. Signed-off-by: David Howells Tested-by: Ralf Baechle Acked-by: Russell King Signed-off-by: Linus Torvalds --- arch/m68k/kernel/process.c | 4 +++- arch/m68k/kernel/sys_m68k.c | 4 +++- 2 files changed, 6 insertions(+), 2 deletions(-) (limited to 'arch/m68k/kernel') diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c index 221d0b71ce3..18732ab2329 100644 --- a/arch/m68k/kernel/process.c +++ b/arch/m68k/kernel/process.c @@ -315,7 +315,9 @@ EXPORT_SYMBOL(dump_fpu); /* * sys_execve() executes a new program. */ -asmlinkage int sys_execve(const char __user *name, char __user * __user *argv, char __user * __user *envp) +asmlinkage int sys_execve(const char __user *name, + const char __user *const __user *argv, + const char __user *const __user *envp) { int error; char * filename; diff --git a/arch/m68k/kernel/sys_m68k.c b/arch/m68k/kernel/sys_m68k.c index 77896692eb0..2f431ece7b5 100644 --- a/arch/m68k/kernel/sys_m68k.c +++ b/arch/m68k/kernel/sys_m68k.c @@ -459,7 +459,9 @@ asmlinkage int sys_getpagesize(void) * Do a system call from kernel instead of calling sys_execve so we * end up with proper pt_regs. */ -int kernel_execve(const char *filename, char *const argv[], char *const envp[]) +int kernel_execve(const char *filename, + const char *const argv[], + const char *const envp[]) { register long __res asm ("%d0") = __NR_execve; register long __a asm ("%d1") = (long)(filename); -- cgit v1.2.3-18-g5258