1 #include "defs.h" 2 3 /* defines copied from linux/sched.h since we can't include that 4 * ourselves (it conflicts with *lots* of libc includes) 5 */ 6 #define CSIGNAL 0x000000ff /* signal mask to be sent at exit */ 7 #define CLONE_VM 0x00000100 /* set if VM shared between processes */ 8 #define CLONE_FS 0x00000200 /* set if fs info shared between processes */ 9 #define CLONE_FILES 0x00000400 /* set if open files shared between processes */ 10 #define CLONE_SIGHAND 0x00000800 /* set if signal handlers shared */ 11 #define CLONE_IDLETASK 0x00001000 /* kernel-only flag */ 12 #define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */ 13 #define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */ 14 #define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */ 15 #define CLONE_THREAD 0x00010000 /* Same thread group? */ 16 #define CLONE_NEWNS 0x00020000 /* New namespace group? */ 17 #define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */ 18 #define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */ 19 #define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */ 20 #define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */ 21 #define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */ 22 #define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */ 23 #define CLONE_STOPPED 0x02000000 /* Start in stopped state */ 24 #define CLONE_NEWUTS 0x04000000 /* New utsname group? */ 25 #define CLONE_NEWIPC 0x08000000 /* New ipcs */ 26 #define CLONE_NEWUSER 0x10000000 /* New user namespace */ 27 #define CLONE_NEWPID 0x20000000 /* New pid namespace */ 28 #define CLONE_NEWNET 0x40000000 /* New network namespace */ 29 #define CLONE_IO 0x80000000 /* Clone io context */ 30 31 #include "xlat/clone_flags.h" 32 33 #if defined IA64 34 # define ARG_FLAGS 0 35 # define ARG_STACK 1 36 # define ARG_STACKSIZE (tcp->scno == SYS_clone2 ? 2 : -1) 37 # define ARG_PTID (tcp->scno == SYS_clone2 ? 3 : 2) 38 # define ARG_CTID (tcp->scno == SYS_clone2 ? 4 : 3) 39 # define ARG_TLS (tcp->scno == SYS_clone2 ? 5 : 4) 40 #elif defined S390 || defined S390X || defined CRISV10 || defined CRISV32 41 # define ARG_STACK 0 42 # define ARG_FLAGS 1 43 # define ARG_PTID 2 44 # define ARG_CTID 3 45 # define ARG_TLS 4 46 #elif defined X86_64 || defined X32 47 /* x86 personality processes have the last two arguments flipped. */ 48 # define ARG_FLAGS 0 49 # define ARG_STACK 1 50 # define ARG_PTID 2 51 # define ARG_CTID ((current_personality != 1) ? 3 : 4) 52 # define ARG_TLS ((current_personality != 1) ? 4 : 3) 53 #elif defined ALPHA || defined TILE || defined OR1K 54 # define ARG_FLAGS 0 55 # define ARG_STACK 1 56 # define ARG_PTID 2 57 # define ARG_CTID 3 58 # define ARG_TLS 4 59 #else 60 # define ARG_FLAGS 0 61 # define ARG_STACK 1 62 # define ARG_PTID 2 63 # define ARG_TLS 3 64 # define ARG_CTID 4 65 #endif 66 67 #if defined I386 || defined X86_64 || defined X32 68 extern void print_user_desc(struct tcb *, long); 69 #endif /* I386 || X86_64 || X32 */ 70 71 SYS_FUNC(clone) 72 { 73 if (exiting(tcp)) { 74 const char *sep = "|"; 75 unsigned long flags = tcp->u_arg[ARG_FLAGS]; 76 tprintf("child_stack=%#lx, ", tcp->u_arg[ARG_STACK]); 77 #ifdef ARG_STACKSIZE 78 if (ARG_STACKSIZE != -1) 79 tprintf("stack_size=%#lx, ", 80 tcp->u_arg[ARG_STACKSIZE]); 81 #endif 82 tprints("flags="); 83 if (!printflags(clone_flags, flags &~ CSIGNAL, NULL)) 84 sep = ""; 85 if ((flags & CSIGNAL) != 0) 86 tprintf("%s%s", sep, signame(flags & CSIGNAL)); 87 if ((flags & (CLONE_PARENT_SETTID|CLONE_CHILD_SETTID 88 |CLONE_CHILD_CLEARTID|CLONE_SETTLS)) == 0) 89 return 0; 90 if (flags & CLONE_PARENT_SETTID) 91 tprintf(", parent_tidptr=%#lx", tcp->u_arg[ARG_PTID]); 92 if (flags & CLONE_SETTLS) { 93 #if defined I386 || defined X86_64 || defined X32 94 # ifndef I386 95 if (current_personality == 1) 96 # endif 97 { 98 tprints(", tls="); 99 print_user_desc(tcp, tcp->u_arg[ARG_TLS]); 100 } 101 # ifndef I386 102 else 103 # endif 104 #endif /* I386 || X86_64 || X32 */ 105 tprintf(", tls=%#lx", tcp->u_arg[ARG_TLS]); 106 } 107 if (flags & (CLONE_CHILD_SETTID|CLONE_CHILD_CLEARTID)) 108 tprintf(", child_tidptr=%#lx", tcp->u_arg[ARG_CTID]); 109 } 110 /* TODO on syscall entry: 111 * We can clear CLONE_PTRACE here since it is an ancient hack 112 * to allow us to catch children, and we use another hack for that. 113 * But CLONE_PTRACE can conceivably be used by malicious programs 114 * to subvert us. By clearing this bit, we can defend against it: 115 * in untraced execution, CLONE_PTRACE should have no effect. 116 * 117 * We can also clear CLONE_UNTRACED, since it allows to start 118 * children outside of our control. At the moment 119 * I'm trying to figure out whether there is a *legitimate* 120 * use of this flag which we should respect. 121 */ 122 return 0; 123 } 124 125 SYS_FUNC(setns) 126 { 127 if (entering(tcp)) { 128 printfd(tcp, tcp->u_arg[0]); 129 tprints(", "); 130 printflags(clone_flags, tcp->u_arg[1], "CLONE_???"); 131 } 132 return 0; 133 } 134 135 SYS_FUNC(unshare) 136 { 137 if (entering(tcp)) 138 printflags(clone_flags, tcp->u_arg[0], "CLONE_???"); 139 return 0; 140 } 141 142 SYS_FUNC(fork) 143 { 144 if (exiting(tcp)) 145 return RVAL_UDECIMAL; 146 return 0; 147 } 148