From b89a81712f486e4f7a606987413e387605fdeaf4 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 27 Sep 2006 01:51:04 -0700 Subject: [PATCH] [PATCH] sysctl: Allow /proc/sys without sys_sysctl Since sys_sysctl is deprecated start allow it to be compiled out. This should catch any remaining user space code that cares, and paves the way for further sysctl cleanups. [akpm@osdl.org: If sys_sysctl() is not compiled-in, emit a warning] Signed-off-by: Eric W. Biederman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ia64/ia32/sys_ia32.c | 2 +- arch/mips/kernel/linux32.c | 4 +- arch/powerpc/kernel/sys_ppc32.c | 2 +- arch/s390/kernel/compat_linux.c | 2 +- arch/sparc64/kernel/sys_sparc32.c | 2 +- arch/x86_64/ia32/sys_ia32.c | 2 +- fs/Kconfig | 19 +++++ init/Kconfig | 31 ++++---- kernel/sysctl.c | 113 ++++++++++-------------------- 9 files changed, 81 insertions(+), 96 deletions(-) diff --git a/arch/ia64/ia32/sys_ia32.c b/arch/ia64/ia32/sys_ia32.c index 6aa3c51619ca..bddbd22706ed 100644 --- a/arch/ia64/ia32/sys_ia32.c +++ b/arch/ia64/ia32/sys_ia32.c @@ -1942,7 +1942,7 @@ struct sysctl32 { unsigned int __unused[4]; }; -#ifdef CONFIG_SYSCTL +#ifdef CONFIG_SYSCTL_SYSCALL asmlinkage long sys32_sysctl (struct sysctl32 __user *args) { diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c index dc500e20cf14..43b1162d714f 100644 --- a/arch/mips/kernel/linux32.c +++ b/arch/mips/kernel/linux32.c @@ -991,7 +991,7 @@ struct sysctl_args32 unsigned int __unused[4]; }; -#ifdef CONFIG_SYSCTL +#ifdef CONFIG_SYSCTL_SYSCALL asmlinkage long sys32_sysctl(struct sysctl_args32 __user *args) { @@ -1032,7 +1032,7 @@ asmlinkage long sys32_sysctl(struct sysctl_args32 __user *args) return error; } -#endif /* CONFIG_SYSCTL */ +#endif /* CONFIG_SYSCTL_SYSCALL */ asmlinkage long sys32_newuname(struct new_utsname __user * name) { diff --git a/arch/powerpc/kernel/sys_ppc32.c b/arch/powerpc/kernel/sys_ppc32.c index 2e292863e982..5e391fc25340 100644 --- a/arch/powerpc/kernel/sys_ppc32.c +++ b/arch/powerpc/kernel/sys_ppc32.c @@ -740,7 +740,7 @@ asmlinkage long compat_sys_umask(u32 mask) return sys_umask((int)mask); } -#ifdef CONFIG_SYSCTL +#ifdef CONFIG_SYSCTL_SYSCALL struct __sysctl_args32 { u32 name; int nlen; diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c index 785c9f70ac98..91b2884fa5c4 100644 --- a/arch/s390/kernel/compat_linux.c +++ b/arch/s390/kernel/compat_linux.c @@ -708,7 +708,7 @@ asmlinkage long sys32_sendfile64(int out_fd, int in_fd, return ret; } -#ifdef CONFIG_SYSCTL +#ifdef CONFIG_SYSCTL_SYSCALL struct __sysctl_args32 { u32 name; int nlen; diff --git a/arch/sparc64/kernel/sys_sparc32.c b/arch/sparc64/kernel/sys_sparc32.c index c88ae23ce812..69444f266e2d 100644 --- a/arch/sparc64/kernel/sys_sparc32.c +++ b/arch/sparc64/kernel/sys_sparc32.c @@ -1016,7 +1016,7 @@ struct __sysctl_args32 { asmlinkage long sys32_sysctl(struct __sysctl_args32 __user *args) { -#ifndef CONFIG_SYSCTL +#ifndef CONFIG_SYSCTL_SYSCALL return -ENOSYS; #else struct __sysctl_args32 tmp; diff --git a/arch/x86_64/ia32/sys_ia32.c b/arch/x86_64/ia32/sys_ia32.c index b0e82c7947dc..f280d3665f4b 100644 --- a/arch/x86_64/ia32/sys_ia32.c +++ b/arch/x86_64/ia32/sys_ia32.c @@ -648,7 +648,7 @@ sys32_pause(void) } -#ifdef CONFIG_SYSCTL +#ifdef CONFIG_SYSCTL_SYSCALL struct sysctl_ia32 { unsigned int name; int nlen; diff --git a/fs/Kconfig b/fs/Kconfig index a27002668bd3..d311198bba43 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -826,6 +826,25 @@ config PROC_VMCORE help Exports the dump image of crashed kernel in ELF format. +config PROC_SYSCTL + bool "Sysctl support (/proc/sys)" if EMBEDDED + depends on PROC_FS + select SYSCTL + default y + ---help--- + The sysctl interface provides a means of dynamically changing + certain kernel parameters and variables on the fly without requiring + a recompile of the kernel or reboot of the system. The primary + interface is through /proc/sys. If you say Y here a tree of + modifiable sysctl entries will be generated beneath the + /proc/sys directory. They are explained in the files + in . Note that enabling this + option will enlarge the kernel by at least 8 KB. + + As it is generally a good thing, you should say Y here unless + building a kernel for install/rescue disks or your system is very + limited in memory. + config SYSFS bool "sysfs file system support" if EMBEDDED default y diff --git a/init/Kconfig b/init/Kconfig index 9a7656f0b5ec..4381006dd666 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -273,21 +273,24 @@ config UID16 This enables the legacy 16-bit UID syscall wrappers. config SYSCTL - bool "Sysctl support" if EMBEDDED - default y + bool + +config SYSCTL_SYSCALL + bool "Sysctl syscall support" + default n + select SYSCTL ---help--- - The sysctl interface provides a means of dynamically changing - certain kernel parameters and variables on the fly without requiring - a recompile of the kernel or reboot of the system. The primary - interface consists of a system call, but if you say Y to "/proc - file system support", a tree of modifiable sysctl entries will be - generated beneath the /proc/sys directory. They are explained in the - files in . Note that enabling this - option will enlarge the kernel by at least 8 KB. - - As it is generally a good thing, you should say Y here unless - building a kernel for install/rescue disks or your system is very - limited in memory. + Enable the deprecated sysctl system call. sys_sysctl uses + binary paths that have been found to be a major pain to maintain + and use. The interface in /proc/sys is now the primary and what + everyone uses. + + Nothing has been using the binary sysctl interface for some time + time now so nothing should break if you disable sysctl syscall + support, and you kernel will get marginally smaller. + + Unless you have an application that uses the sys_syscall interface + you should probably say N here. config KALLSYMS bool "Load all symbols for debugging/kksymoops" if EMBEDDED diff --git a/kernel/sysctl.c b/kernel/sysctl.c index bcb3a181dbb2..8bfa7d117c54 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -137,8 +137,11 @@ extern int no_unaligned_warning; extern int max_lock_depth; #endif -static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t, - ctl_table *, void **); +#ifdef CONFIG_SYSCTL_SYSCALL +static int parse_table(int __user *, int, void __user *, size_t __user *, + void __user *, size_t, ctl_table *, void **); +#endif + static int proc_doutsstring(ctl_table *table, int write, struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos); @@ -165,7 +168,7 @@ int sysctl_legacy_va_layout; /* /proc declarations: */ -#ifdef CONFIG_PROC_FS +#ifdef CONFIG_PROC_SYSCTL static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *); static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *); @@ -1166,12 +1169,13 @@ static void start_unregistering(struct ctl_table_header *p) void __init sysctl_init(void) { -#ifdef CONFIG_PROC_FS +#ifdef CONFIG_PROC_SYSCTL register_proc_table(root_table, proc_sys_root, &root_table_header); init_irq_proc(); #endif } +#ifdef CONFIG_SYSCTL_SYSCALL int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen) { @@ -1225,6 +1229,7 @@ asmlinkage long sys_sysctl(struct __sysctl_args __user *args) unlock_kernel(); return error; } +#endif /* CONFIG_SYSCTL_SYSCALL */ /* * ctl_perm does NOT grant the superuser all rights automatically, because @@ -1251,6 +1256,7 @@ static inline int ctl_perm(ctl_table *table, int op) return test_perm(table->mode, op); } +#ifdef CONFIG_SYSCTL_SYSCALL static int parse_table(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen, @@ -1340,6 +1346,7 @@ int do_sysctl_strategy (ctl_table *table, } return 0; } +#endif /* CONFIG_SYSCTL_SYSCALL */ /** * register_sysctl_table - register a sysctl hierarchy @@ -1427,7 +1434,7 @@ struct ctl_table_header *register_sysctl_table(ctl_table * table, else list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry); spin_unlock(&sysctl_lock); -#ifdef CONFIG_PROC_FS +#ifdef CONFIG_PROC_SYSCTL register_proc_table(table, proc_sys_root, tmp); #endif return tmp; @@ -1445,18 +1452,31 @@ void unregister_sysctl_table(struct ctl_table_header * header) might_sleep(); spin_lock(&sysctl_lock); start_unregistering(header); -#ifdef CONFIG_PROC_FS +#ifdef CONFIG_PROC_SYSCTL unregister_proc_table(header->ctl_table, proc_sys_root); #endif spin_unlock(&sysctl_lock); kfree(header); } +#else /* !CONFIG_SYSCTL */ +struct ctl_table_header * register_sysctl_table(ctl_table * table, + int insert_at_head) +{ + return NULL; +} + +void unregister_sysctl_table(struct ctl_table_header * table) +{ +} + +#endif /* CONFIG_SYSCTL */ + /* * /proc/sys support */ -#ifdef CONFIG_PROC_FS +#ifdef CONFIG_PROC_SYSCTL /* Scan the sysctl entries in table and add them all into /proc */ static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set) @@ -2318,6 +2338,7 @@ int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, #endif /* CONFIG_PROC_FS */ +#ifdef CONFIG_SYSCTL_SYSCALL /* * General sysctl support routines */ @@ -2460,11 +2481,19 @@ int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, return 1; } -#else /* CONFIG_SYSCTL */ +#else /* CONFIG_SYSCTL_SYSCALL */ asmlinkage long sys_sysctl(struct __sysctl_args __user *args) { + static int msg_count; + + if (msg_count < 5) { + msg_count++; + printk(KERN_INFO + "warning: process `%s' used the removed sysctl " + "system call\n", current->comm); + } return -ENOSYS; } @@ -2496,73 +2525,7 @@ int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, return -ENOSYS; } -int proc_dostring(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, - struct file *filp, - void __user *buffer, - size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - -struct ctl_table_header * register_sysctl_table(ctl_table * table, - int insert_at_head) -{ - return NULL; -} - -void unregister_sysctl_table(struct ctl_table_header * table) -{ -} - -#endif /* CONFIG_SYSCTL */ +#endif /* CONFIG_SYSCTL_SYSCALL */ /* * No sense putting this after each symbol definition, twice, -- 2.20.1