Re: [PATCH v2 1/7] mm: Add process_vm_mmap() syscall declaration
From: Ira Weiny <hidden>
Date: 2019-05-21 00:27:40
Also in:
linux-mm, lkml
On Mon, May 20, 2019 at 05:00:07PM +0300, Kirill Tkhai wrote:
Similar to process_vm_readv() and process_vm_writev(), add declarations of a new syscall, which will allow to map memory from or to another process.
Shouldn't this be the last patch in the series so that the syscall is actually implemented first? Ira
quoted hunk ↗ jump to hunk
Signed-off-by: Kirill Tkhai <redacted> --- arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 2 ++ include/linux/syscalls.h | 5 +++++ include/uapi/asm-generic/unistd.h | 5 ++++- init/Kconfig | 9 +++++---- kernel/sys_ni.c | 2 ++ 6 files changed, 19 insertions(+), 5 deletions(-)diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index ad968b7bac72..99d6e0085576 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl@@ -438,3 +438,4 @@ 431 i386 fsconfig sys_fsconfig __ia32_sys_fsconfig 432 i386 fsmount sys_fsmount __ia32_sys_fsmount 433 i386 fspick sys_fspick __ia32_sys_fspick +434 i386 process_vm_mmap sys_process_vm_mmap __ia32_compat_sys_process_vm_mmapdiff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index b4e6f9e6204a..46d7d2898f7a 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl@@ -355,6 +355,7 @@ 431 common fsconfig __x64_sys_fsconfig 432 common fsmount __x64_sys_fsmount 433 common fspick __x64_sys_fspick +434 common process_vm_mmap __x64_sys_process_vm_mmap # # x32-specific system call numbers start at 512 to avoid cache impact@@ -398,3 +399,4 @@ 545 x32 execveat __x32_compat_sys_execveat/ptregs 546 x32 preadv2 __x32_compat_sys_preadv64v2 547 x32 pwritev2 __x32_compat_sys_pwritev64v2 +548 x32 process_vm_mmap __x32_compat_sys_process_vm_mmapdiff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index e2870fe1be5b..7d8ae36589cf 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h@@ -997,6 +997,11 @@ asmlinkage long sys_fspick(int dfd, const char __user *path, unsigned int flags) asmlinkage long sys_pidfd_send_signal(int pidfd, int sig, siginfo_t __user *info, unsigned int flags); +asmlinkage long sys_process_vm_mmap(pid_t pid, + unsigned long src_addr, + unsigned long len, + unsigned long dst_addr, + unsigned long flags); /* * Architecture-specific system callsdiff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index a87904daf103..b7aaa5ae02da 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h@@ -844,9 +844,12 @@ __SYSCALL(__NR_fsconfig, sys_fsconfig) __SYSCALL(__NR_fsmount, sys_fsmount) #define __NR_fspick 433 __SYSCALL(__NR_fspick, sys_fspick) +#define __NR_process_vm_mmap 424 +__SC_COMP(__NR_process_vm_mmap, sys_process_vm_mmap, \ + compat_sys_process_vm_mmap) #undef __NR_syscalls -#define __NR_syscalls 434 +#define __NR_syscalls 435 /* * 32 bit systems traditionally used differentdiff --git a/init/Kconfig b/init/Kconfig index 8b9ffe236e4f..604db5f14718 100644 --- a/init/Kconfig +++ b/init/Kconfig@@ -320,13 +320,14 @@ config POSIX_MQUEUE_SYSCTL default y config CROSS_MEMORY_ATTACH - bool "Enable process_vm_readv/writev syscalls" + bool "Enable process_vm_readv/writev/mmap syscalls" depends on MMU default y help - Enabling this option adds the system calls process_vm_readv and - process_vm_writev which allow a process with the correct privileges - to directly read from or write to another process' address space. + Enabling this option adds the system calls process_vm_readv, + process_vm_writev and process_vm_mmap, which allow a process + with the correct privileges to directly read from or write to + or mmap another process' address space. See the man page for more details. config USELIBdiff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 4d9ae5ea6caf..6f51634f4f7e 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c@@ -316,6 +316,8 @@ COND_SYSCALL(process_vm_readv); COND_SYSCALL_COMPAT(process_vm_readv); COND_SYSCALL(process_vm_writev); COND_SYSCALL_COMPAT(process_vm_writev); +COND_SYSCALL(process_vm_mmap); +COND_SYSCALL_COMPAT(process_vm_mmap); /* compare kernel pointers */ COND_SYSCALL(kcmp);