diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/arm/socket.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/arm/socket.S | 35 |
1 files changed, 27 insertions, 8 deletions
diff --git a/sysdeps/unix/sysv/linux/arm/socket.S b/sysdeps/unix/sysv/linux/arm/socket.S index b51d887a7f..92c7e907a2 100644 --- a/sysdeps/unix/sysv/linux/arm/socket.S +++ b/sysdeps/unix/sysv/linux/arm/socket.S @@ -35,12 +35,19 @@ #define __socket P(__,socket) #endif -#define PUSHARGS_1 stmfd ip!, {a1} -#define PUSHARGS_2 stmfd ip!, {a1, a2} -#define PUSHARGS_3 stmfd ip!, {a1, a2, a3} -#define PUSHARGS_4 stmfd ip!, {a1, a2, a3, a4} -#define PUSHARGS_5 stmfd ip!, {a1, a2, a3, a4} /* Caller has already pushed arg 5 */ -#define PUSHARGS_6 stmfd ip!, {a1, a2, a3, a4} +#define PUSHARGS_1 stmfd sp!, {a1} +#define PUSHARGS_2 stmfd sp!, {a1, a2} +#define PUSHARGS_3 stmfd sp!, {a1, a2, a3} +#define PUSHARGS_4 stmfd sp!, {a1, a2, a3, a4} +#define PUSHARGS_5 stmfd sp!, {a1, a2, a3, a4} /* Caller has already pushed arg 5 */ +#define PUSHARGS_6 stmfd sp!, {a1, a2, a3, a4} + +#define POPARGS_1 add sp, sp, #4 +#define POPARGS_2 add sp, sp, #8 +#define POPARGS_3 add sp, sp, #12 +#define POPARGS_4 add sp, sp, #16 +#define POPARGS_5 add sp, sp, #16 +#define POPARGS_6 add sp, sp, #16 #ifndef NARGS #define NARGS 3 /* If we were called with no wrapper, this is really socket() */ @@ -48,15 +55,27 @@ .globl __socket ENTRY (__socket) + /* This code previously moved sp into ip and stored the args using + stmdb ip!, {a1-a4}. It did not modify sp, so the stack never had + to be restored after the syscall completed. It saved an + instruction and meant no stack cleanup work was required. + + This will not work in the case of a socket call being interrupted + by a signal. If the signal handler uses any stack the arguments + to socket will be trashed. The results of a restart of any + socket call are then unpredictable. */ + /* Push args onto the stack. */ - mov ip, sp P(PUSHARGS_,NARGS) /* Do the system call trap. */ mov a1, $P(SOCKOP_,socket) - mov a2, ip + mov a2, sp swi SYS_ify(socketcall) + /* Pop args off the stack */ + P(POPARGS_,NARGS) + /* r0 is < 0 if there was an error. */ cmn r0, $124 bhs PLTJMP(syscall_error) |