Currently arm64 personality syscall uses wrapper __arm64_sys_personality to redirect to __arm64_sys_arm64_personality, it's easily confused, Whereas using an normal hook arch_check_personality() can reject additional settings like this for special case of different architectures.
This makes code clean and easier for subsequent modification. Signed-off-by: Wang ShaoBo <bobo.shaobow...@huawei.com> Reviewed-by: Dominik Brodowski <li...@dominikbrodowski.net> --- arch/arm64/kernel/sys.c | 7 +++---- include/linux/syscalls.h | 10 ---------- kernel/exec_domain.c | 14 +++++++++++++- 3 files changed, 16 insertions(+), 15 deletions(-) diff --git a/arch/arm64/kernel/sys.c b/arch/arm64/kernel/sys.c index d5ffaaab31a7..5c01816d7a77 100644 --- a/arch/arm64/kernel/sys.c +++ b/arch/arm64/kernel/sys.c @@ -28,12 +28,13 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len, return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT); } -SYSCALL_DEFINE1(arm64_personality, unsigned int, personality) +int arch_check_personality(unsigned int personality) { if (personality(personality) == PER_LINUX32 && !system_supports_32bit_el0()) return -EINVAL; - return ksys_personality(personality); + + return 0; } asmlinkage long sys_ni_syscall(void); @@ -46,8 +47,6 @@ asmlinkage long __arm64_sys_ni_syscall(const struct pt_regs *__unused) /* * Wrappers to pass the pt_regs argument. */ -#define __arm64_sys_personality __arm64_sys_arm64_personality - #undef __SYSCALL #define __SYSCALL(nr, sym) asmlinkage long __arm64_##sym(const struct pt_regs *); #include <asm/unistd.h> diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 1815065d52f3..3dbbad498027 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1393,16 +1393,6 @@ static inline long ksys_truncate(const char __user *pathname, loff_t length) return do_sys_truncate(pathname, length); } -static inline unsigned int ksys_personality(unsigned int personality) -{ - unsigned int old = current->personality; - - if (personality != 0xffffffff) - set_personality(personality); - - return old; -} - /* for __ARCH_WANT_SYS_IPC */ long ksys_semtimedop(int semid, struct sembuf __user *tsops, unsigned int nsops, diff --git a/kernel/exec_domain.c b/kernel/exec_domain.c index 33f07c5f2515..f3682f4bf205 100644 --- a/kernel/exec_domain.c +++ b/kernel/exec_domain.c @@ -35,9 +35,21 @@ static int __init proc_execdomains_init(void) module_init(proc_execdomains_init); #endif +int __weak arch_check_personality(unsigned int personality) +{ + return 0; +} + SYSCALL_DEFINE1(personality, unsigned int, personality) { - unsigned int old = current->personality; + int err; + unsigned int old; + + err = arch_check_personality(personality); + if (err) + return err; + + old = current->personality; if (personality != 0xffffffff) set_personality(personality); -- 2.17.1