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/um/kernel/exec.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/um/kernel/exec.c') diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index 97974c1bdd12..59b20d93b6d4 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -44,7 +44,7 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp) PT_REGS_SP(regs) = esp; } -static long execve1(char *file, char __user * __user *argv, +static long execve1(const char *file, char __user * __user *argv, char __user *__user *env) { long error; @@ -61,7 +61,7 @@ static long execve1(char *file, char __user * __user *argv, return error; } -long um_execve(char *file, char __user *__user *argv, char __user *__user *env) +long um_execve(const char *file, char __user *__user *argv, char __user *__user *env) { long err; @@ -71,7 +71,7 @@ long um_execve(char *file, char __user *__user *argv, char __user *__user *env) return err; } -long sys_execve(char __user *file, char __user *__user *argv, +long sys_execve(const char __user *file, char __user *__user *argv, char __user *__user *env) { long error; -- cgit v1.2.3 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/um/kernel/exec.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/um/kernel/exec.c') diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index 59b20d93b6d4..cd145eda3579 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -44,8 +44,9 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp) PT_REGS_SP(regs) = esp; } -static long execve1(const char *file, char __user * __user *argv, - char __user *__user *env) +static long execve1(const char *file, + const char __user *const __user *argv, + const char __user *const __user *env) { long error; -- cgit v1.2.3 From cb1dcc0ff4b57873210100fc9d70defa81af43d4 Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Wed, 22 Sep 2010 13:05:07 -0700 Subject: uml: fix compile warning This fixes: incompatible pointer type: => 89 arch/um/kernel/exec.c: warning: passing argument 2 of 'execve1' from incompatible pointer type: => 69, 85 arch/um/kernel/exec.c: warning: passing argument 3 of 'execve1' from incompatible pointer type: => 69, 85 which was introduced by d7627467b7a8d ("Make do_execve() take a const filename pointer") Signed-off-by: Richard Weinberger Cc: David Howells Cc: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/kernel/exec.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/um/kernel/exec.c') diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index cd145eda3579..49b5e1eb3262 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -62,7 +62,7 @@ static long execve1(const char *file, return error; } -long um_execve(const char *file, char __user *__user *argv, char __user *__user *env) +long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env) { long err; @@ -72,8 +72,8 @@ long um_execve(const char *file, char __user *__user *argv, char __user *__user return err; } -long sys_execve(const char __user *file, char __user *__user *argv, - char __user *__user *env) +long sys_execve(const char __user *file, const char __user *const __user *argv, + const char __user *const __user *env) { long error; char *filename; -- cgit v1.2.3 From 9a181c58617134822ae596339dbea076ef9b5cf7 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Sat, 11 Sep 2010 18:38:03 +0200 Subject: uml: kill big kernel lock Three uml device drivers still use the big kernel lock, but all of them can be safely converted to using a per-driver mutex instead. Most likely this is not even necessary, so after further review these can and should be removed as well. The exec system call no longer requires the BKL either, so remove it from there, too. Signed-off-by: Arnd Bergmann Cc: Jeff Dike Cc: user-mode-linux-devel@lists.sourceforge.net --- arch/um/kernel/exec.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/um/kernel/exec.c') diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index cd145eda3579..460ce86f4019 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -78,13 +78,11 @@ long sys_execve(const char __user *file, char __user *__user *argv, long error; char *filename; - lock_kernel(); filename = getname(file); error = PTR_ERR(filename); if (IS_ERR(filename)) goto out; error = execve1(filename, argv, env); putname(filename); out: - unlock_kernel(); return error; } -- cgit v1.2.3 From 451a3c24b0135bce54542009b5fde43846c7cf67 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 17 Nov 2010 16:26:55 +0100 Subject: BKL: remove extraneous #include The big kernel lock has been removed from all these files at some point, leaving only the #include. Remove this too as a cleanup. Signed-off-by: Arnd Bergmann Signed-off-by: Linus Torvalds --- arch/um/kernel/exec.c | 1 - 1 file changed, 1 deletion(-) (limited to 'arch/um/kernel/exec.c') diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index 340268be00b5..09bd7b585726 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -5,7 +5,6 @@ #include "linux/stddef.h" #include "linux/fs.h" -#include "linux/smp_lock.h" #include "linux/ptrace.h" #include "linux/sched.h" #include "linux/slab.h" -- cgit v1.2.3