From bdbcb22ded123b964c3e8583846d08fcc0b5d178 Mon Sep 17 00:00:00 2001 From: Peter Jung Date: Fri, 18 Oct 2024 22:23:25 +0200 Subject: [PATCH 4/5] ksm Signed-off-by: Peter Jung --- arch/alpha/kernel/syscalls/syscall.tbl | 3 + arch/arm/tools/syscall.tbl | 3 + arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 6 + arch/ia64/kernel/syscalls/syscall.tbl | 3 + arch/m68k/kernel/syscalls/syscall.tbl | 3 + arch/microblaze/kernel/syscalls/syscall.tbl | 3 + arch/mips/kernel/syscalls/syscall_n32.tbl | 3 + arch/mips/kernel/syscalls/syscall_n64.tbl | 3 + arch/mips/kernel/syscalls/syscall_o32.tbl | 3 + arch/parisc/kernel/syscalls/syscall.tbl | 3 + arch/powerpc/kernel/syscalls/syscall.tbl | 3 + arch/s390/kernel/syscalls/syscall.tbl | 3 + arch/sh/kernel/syscalls/syscall.tbl | 3 + arch/sparc/kernel/syscalls/syscall.tbl | 3 + arch/x86/entry/syscalls/syscall_32.tbl | 3 + arch/x86/entry/syscalls/syscall_64.tbl | 3 + arch/xtensa/kernel/syscalls/syscall.tbl | 3 + include/linux/syscalls.h | 3 + include/uapi/asm-generic/unistd.h | 11 +- kernel/sys.c | 147 ++++++++++++++++++++ kernel/sys_ni.c | 3 + 22 files changed, 218 insertions(+), 2 deletions(-) diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl index ad37569d0507..9f4311e21c42 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -492,3 +492,6 @@ 560 common set_mempolicy_home_node sys_ni_syscall 561 common cachestat sys_cachestat 562 common fchmodat2 sys_fchmodat2 +563 common process_ksm_enable sys_process_ksm_enable +564 common process_ksm_disable sys_process_ksm_disable +565 common process_ksm_status sys_process_ksm_status diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index c572d6c3dee0..8d40b3a4572e 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -466,3 +466,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h index bd77253b62e0..f33190f17ebb 100644 --- a/arch/arm64/include/asm/unistd.h +++ b/arch/arm64/include/asm/unistd.h @@ -39,7 +39,7 @@ #define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5) #define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800) -#define __NR_compat_syscalls 453 +#define __NR_compat_syscalls 456 #endif #define __ARCH_WANT_SYS_CLONE diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h index 545a4a7b5371..87b17264af4f 100644 --- a/arch/arm64/include/asm/unistd32.h +++ b/arch/arm64/include/asm/unistd32.h @@ -911,6 +911,12 @@ __SYSCALL(__NR_set_mempolicy_home_node, sys_set_mempolicy_home_node) __SYSCALL(__NR_cachestat, sys_cachestat) #define __NR_fchmodat2 452 __SYSCALL(__NR_fchmodat2, sys_fchmodat2) +#define __NR_process_ksm_enable 453 +__SYSCALL(__NR_process_ksm_enable, sys_process_ksm_enable) +#define __NR_process_ksm_disable 454 +__SYSCALL(__NR_process_ksm_disable, sys_process_ksm_disable) +#define __NR_process_ksm_status 455 +__SYSCALL(__NR_process_ksm_status, sys_process_ksm_status) /* * Please add new compat syscalls above this comment and update diff --git a/arch/ia64/kernel/syscalls/syscall.tbl b/arch/ia64/kernel/syscalls/syscall.tbl index 83d8609aec03..2c370b5695ef 100644 --- a/arch/ia64/kernel/syscalls/syscall.tbl +++ b/arch/ia64/kernel/syscalls/syscall.tbl @@ -373,3 +373,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl index 259ceb125367..346033761c74 100644 --- a/arch/m68k/kernel/syscalls/syscall.tbl +++ b/arch/m68k/kernel/syscalls/syscall.tbl @@ -452,3 +452,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl index a3798c2637fd..3d550ff347e4 100644 --- a/arch/microblaze/kernel/syscalls/syscall.tbl +++ b/arch/microblaze/kernel/syscalls/syscall.tbl @@ -458,3 +458,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl index 4a296124604a..2eb6c231df12 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -391,3 +391,6 @@ 450 n32 set_mempolicy_home_node sys_set_mempolicy_home_node 451 n32 cachestat sys_cachestat 452 n32 fchmodat2 sys_fchmodat2 +453 n32 process_ksm_enable sys_process_ksm_enable +454 n32 process_ksm_disable sys_process_ksm_disable +455 n32 process_ksm_status sys_process_ksm_status diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl index cb5e757f6621..5c17a0a34f68 100644 --- a/arch/mips/kernel/syscalls/syscall_n64.tbl +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl @@ -367,3 +367,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 n64 cachestat sys_cachestat 452 n64 fchmodat2 sys_fchmodat2 +453 n64 process_ksm_enable sys_process_ksm_enable +454 n64 process_ksm_disable sys_process_ksm_disable +455 n64 process_ksm_status sys_process_ksm_status diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl index 1ee62a861380..b6a725a4e9b0 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -440,3 +440,6 @@ 450 o32 set_mempolicy_home_node sys_set_mempolicy_home_node 451 o32 cachestat sys_cachestat 452 o32 fchmodat2 sys_fchmodat2 +453 o32 process_ksm_enable sys_process_ksm_enable +454 o32 process_ksm_disable sys_process_ksm_disable +455 o32 process_ksm_status sys_process_ksm_status diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl index 73f560e30957..6d792dcdc92c 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -451,3 +451,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index 40f6751271d3..5501db65fe1b 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -543,3 +543,6 @@ 450 nospu set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl index 51cc3616d5f9..9489656f77b4 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -455,3 +455,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status sys_process_ksm_status diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl index 7e1ceb2ba572..2d6a4626850e 100644 --- a/arch/sh/kernel/syscalls/syscall.tbl +++ b/arch/sh/kernel/syscalls/syscall.tbl @@ -456,3 +456,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl index d0f535230ad8..f92c0b1d5571 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -498,3 +498,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index 38db5ef2329f..12f04cc14dde 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -457,3 +457,6 @@ 450 i386 set_mempolicy_home_node sys_set_mempolicy_home_node 451 i386 cachestat sys_cachestat 452 i386 fchmodat2 sys_fchmodat2 +453 i386 process_ksm_enable sys_process_ksm_enable +454 i386 process_ksm_disable sys_process_ksm_disable +455 i386 process_ksm_status sys_process_ksm_status diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 1d6eee30eceb..38faca76e9a0 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -375,6 +375,9 @@ 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 453 64 map_shadow_stack sys_map_shadow_stack +454 common process_ksm_enable sys_process_ksm_enable +455 common process_ksm_disable sys_process_ksm_disable +456 common process_ksm_status sys_process_ksm_status # # Due to a historical design error, certain syscalls are numbered differently diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl index fc1a4f3c81d9..83f5032b2526 100644 --- a/arch/xtensa/kernel/syscalls/syscall.tbl +++ b/arch/xtensa/kernel/syscalls/syscall.tbl @@ -423,3 +423,6 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 +453 common process_ksm_enable sys_process_ksm_enable +454 common process_ksm_disable sys_process_ksm_disable +455 common process_ksm_status sys_process_ksm_status diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 36c592e43d65..45654b8e3ddb 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -800,6 +800,9 @@ asmlinkage long sys_madvise(unsigned long start, size_t len, int behavior); asmlinkage long sys_process_madvise(int pidfd, const struct iovec __user *vec, size_t vlen, int behavior, unsigned int flags); asmlinkage long sys_process_mrelease(int pidfd, unsigned int flags); +asmlinkage long sys_process_ksm_enable(int pidfd, unsigned int flags); +asmlinkage long sys_process_ksm_disable(int pidfd, unsigned int flags); +asmlinkage long sys_process_ksm_status(int pidfd, unsigned int flags); asmlinkage long sys_remap_file_pages(unsigned long start, unsigned long size, unsigned long prot, unsigned long pgoff, unsigned long flags); diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index 05c412c58239..91fab12579bc 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -823,8 +823,17 @@ __SYSCALL(__NR_cachestat, sys_cachestat) #define __NR_fchmodat2 452 __SYSCALL(__NR_fchmodat2, sys_fchmodat2) +#define __NR_process_ksm_enable 453 +__SYSCALL(__NR_process_ksm_enable, sys_process_ksm_enable) + +#define __NR_process_ksm_disable 454 +__SYSCALL(__NR_process_ksm_disable, sys_process_ksm_disable) + +#define __NR_process_ksm_status 455 +__SYSCALL(__NR_process_ksm_status, sys_process_ksm_status) + #undef __NR_syscalls -#define __NR_syscalls 453 +#define __NR_syscalls 456 /* * 32 bit systems traditionally used different diff --git a/kernel/sys.c b/kernel/sys.c index 44b575990333..063c12689b07 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -2754,6 +2754,153 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, return error; } +#ifdef CONFIG_KSM +enum pkc_action { + PKSM_ENABLE = 0, + PKSM_DISABLE, + PKSM_STATUS, +}; + +static long do_process_ksm_control(int pidfd, enum pkc_action action) +{ + long ret; + struct pid *pid; + struct task_struct *task; + struct mm_struct *mm; + unsigned int f_flags; + + pid = pidfd_get_pid(pidfd, &f_flags); + if (IS_ERR(pid)) { + ret = PTR_ERR(pid); + goto out; + } + + task = get_pid_task(pid, PIDTYPE_PID); + if (!task) { + ret = -ESRCH; + goto put_pid; + } + + /* Require PTRACE_MODE_READ to avoid leaking ASLR metadata. */ + mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); + if (IS_ERR_OR_NULL(mm)) { + ret = IS_ERR(mm) ? PTR_ERR(mm) : -ESRCH; + goto release_task; + } + + /* Require CAP_SYS_NICE for influencing process performance. */ + if (!capable(CAP_SYS_NICE)) { + ret = -EPERM; + goto release_mm; + } + + if (mmap_write_lock_killable(mm)) { + ret = -EINTR; + goto release_mm; + } + + switch (action) { + case PKSM_ENABLE: + ret = ksm_enable_merge_any(mm); + break; + case PKSM_DISABLE: + ret = ksm_disable_merge_any(mm); + break; + case PKSM_STATUS: + ret = !!test_bit(MMF_VM_MERGE_ANY, &mm->flags); + break; + } + + mmap_write_unlock(mm); + +release_mm: + mmput(mm); +release_task: + put_task_struct(task); +put_pid: + put_pid(pid); +out: + return ret; +} +#endif /* CONFIG_KSM */ + +SYSCALL_DEFINE2(process_ksm_enable, int, pidfd, unsigned int, flags) +{ +#ifdef CONFIG_KSM + if (flags != 0) + return -EINVAL; + + return do_process_ksm_control(pidfd, PKSM_ENABLE); +#else /* CONFIG_KSM */ + return -ENOSYS; +#endif /* CONFIG_KSM */ +} + +SYSCALL_DEFINE2(process_ksm_disable, int, pidfd, unsigned int, flags) +{ +#ifdef CONFIG_KSM + if (flags != 0) + return -EINVAL; + + return do_process_ksm_control(pidfd, PKSM_DISABLE); +#else /* CONFIG_KSM */ + return -ENOSYS; +#endif /* CONFIG_KSM */ +} + +SYSCALL_DEFINE2(process_ksm_status, int, pidfd, unsigned int, flags) +{ +#ifdef CONFIG_KSM + if (flags != 0) + return -EINVAL; + + return do_process_ksm_control(pidfd, PKSM_STATUS); +#else /* CONFIG_KSM */ + return -ENOSYS; +#endif /* CONFIG_KSM */ +} + +#ifdef CONFIG_KSM +static ssize_t process_ksm_enable_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%u\n", __NR_process_ksm_enable); +} +static struct kobj_attribute process_ksm_enable_attr = __ATTR_RO(process_ksm_enable); + +static ssize_t process_ksm_disable_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%u\n", __NR_process_ksm_disable); +} +static struct kobj_attribute process_ksm_disable_attr = __ATTR_RO(process_ksm_disable); + +static ssize_t process_ksm_status_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%u\n", __NR_process_ksm_status); +} +static struct kobj_attribute process_ksm_status_attr = __ATTR_RO(process_ksm_status); + +static struct attribute *process_ksm_sysfs_attrs[] = { + &process_ksm_enable_attr.attr, + &process_ksm_disable_attr.attr, + &process_ksm_status_attr.attr, + NULL, +}; + +static const struct attribute_group process_ksm_sysfs_attr_group = { + .attrs = process_ksm_sysfs_attrs, + .name = "process_ksm", +}; + +static int __init process_ksm_sysfs_init(void) +{ + return sysfs_create_group(kernel_kobj, &process_ksm_sysfs_attr_group); +} +subsys_initcall(process_ksm_sysfs_init); +#endif /* CONFIG_KSM */ + SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, struct getcpu_cache __user *, unused) { diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index e8e117787377..f8f3aa47e1b6 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -184,6 +184,9 @@ COND_SYSCALL(mincore); COND_SYSCALL(madvise); COND_SYSCALL(process_madvise); COND_SYSCALL(process_mrelease); +COND_SYSCALL(process_ksm_enable); +COND_SYSCALL(process_ksm_disable); +COND_SYSCALL(process_ksm_status); COND_SYSCALL(remap_file_pages); COND_SYSCALL(mbind); COND_SYSCALL(get_mempolicy); -- 2.47.0.rc0