diff --git a/lib/libsysdecode/mktables b/lib/libsysdecode/mktables --- a/lib/libsysdecode/mktables +++ b/lib/libsysdecode/mktables @@ -116,7 +116,7 @@ gen_table "pathconfname" "_PC_[A-Z4_]+[[:space:]]+[0-9]+" "sys/unistd.h" gen_table "prio" "PRIO_[A-Z]+[[:space:]]+[0-9]" "sys/resource.h" gen_table "procctlcmd" "PROC_[A-Z_]+[[:space:]]+[0-9]" "sys/procctl.h" "PROC_TRACE_CTL_" -gen_table "ptraceop" "PT_[[:alnum:]_]+[[:space:]]+[0-9]+" "sys/ptrace.h" +gen_table "ptraceop" "PT_[[:alnum:]_]+[[:space:]]+[0-9]+" "sys/ptrace.h" "PT_GET_SC_ARGS_ALL" gen_table "quotactlcmds" "Q_[A-Z]+[[:space:]]+0x[0-9]+" "ufs/ufs/quota.h" gen_table "rebootopt" "RB_[A-Z]+[[:space:]]+0x[0-9]+" "sys/reboot.h" gen_table "rforkflags" "RF[A-Z]+[[:space:]]+\([0-9]+<<[0-9]+\)" "sys/unistd.h" diff --git a/sys/amd64/linux/linux_ptrace.c b/sys/amd64/linux/linux_ptrace.c --- a/sys/amd64/linux/linux_ptrace.c +++ b/sys/amd64/linux/linux_ptrace.c @@ -93,6 +93,12 @@ LINUX_PTRACE_O_TRACESECCOMP | LINUX_PTRACE_O_EXITKILL | \ LINUX_PTRACE_O_SUSPEND_SECCOMP) +#define LINUX_PTRACE_SYSCALL_INFO_NONE 0 +#define LINUX_PTRACE_SYSCALL_INFO_ENTRY 1 +#define LINUX_PTRACE_SYSCALL_INFO_EXIT 2 + +#define LINUX_ARCH_AMD64 0xc000003e + static int map_signum(int lsig, int *bsigp) { @@ -172,6 +178,28 @@ l_ulong ss; }; +struct syscall_info { + uint8_t op; + uint32_t arch; + uint64_t instruction_pointer; + uint64_t stack_pointer; + union { + struct { + uint64_t nr; + uint64_t args[6]; + } entry; + struct { + int64_t rval; + uint8_t is_error; + } exit; + struct { + uint64_t nr; + uint64_t args[6]; + uint32_t ret_data; + } seccomp; + }; +}; + /* * Translate amd64 ptrace registers between Linux and FreeBSD formats. * The translation is pretty straighforward, for all registers but @@ -495,11 +523,75 @@ } static int -linux_ptrace_get_syscall_info(struct thread *td, pid_t pid, l_ulong addr, l_ulong data) +linux_ptrace_get_syscall_info(struct thread *td, pid_t pid, + l_ulong addr, l_ulong data) { + struct ptrace_lwpinfo lwpinfo; + struct ptrace_sc_ret sr; + struct reg b_reg; + struct syscall_info si; + int error; - linux_msg(td, "PTRACE_GET_SYSCALL_INFO not implemented; returning EINVAL"); - return (EINVAL); + error = kern_ptrace(td, PT_LWPINFO, pid, &lwpinfo, sizeof(lwpinfo)); + if (error != 0) { + linux_msg(td, "PT_LWPINFO failed with error %d", error); + return (error); + } + + memset(&si, 0, sizeof(si)); + + if (lwpinfo.pl_flags & PL_FLAG_SCE) { + si.op = LINUX_PTRACE_SYSCALL_INFO_ENTRY; + si.entry.nr = lwpinfo.pl_syscall_code; + /* + * The reason for using PT_GET_SC_ARGS_ALL instead + * of PT_GET_SC_ARGS is to emulate Linux bug which strace(1) + * depends on: at initialization it tests whether ptrace works + * by calling close(2), or some other single-argument syscall, + * _with six arguments_, and then verifies whether it can + * fetch them all using this API; otherwise it bails out. + */ + error = kern_ptrace(td, PT_GET_SC_ARGS_ALL, pid, + &si.entry.args, sizeof(si.entry.args)); + if (error != 0) { + linux_msg(td, "PT_GET_SC_ARGS_ALL failed with error %d", + error); + return (error); + } + } else if (lwpinfo.pl_flags & PL_FLAG_SCX) { + si.op = LINUX_PTRACE_SYSCALL_INFO_EXIT; + error = kern_ptrace(td, PT_GET_SC_RET, pid, &sr, sizeof(sr)); + + if (error != 0) { + linux_msg(td, "PT_GET_SC_RET failed with error %d", + error); + return (error); + } + + if (sr.sr_error == 0) { + si.exit.rval = sr.sr_retval[0]; + si.exit.is_error = 0; + } else { + si.exit.rval = bsd_to_linux_errno(sr.sr_error); + si.exit.is_error = 1; + } + } else { + si.op = LINUX_PTRACE_SYSCALL_INFO_NONE; + } + + error = kern_ptrace(td, PT_GETREGS, pid, &b_reg, 0); + if (error != 0) + return (error); + + si.arch = LINUX_ARCH_AMD64; + si.instruction_pointer = b_reg.r_rip; + si.stack_pointer = b_reg.r_rsp; + + error = copyout(&si, (void *)data, sizeof(si)); + if (error == 0) + td->td_retval[0] = sizeof(si); + + return (error); } int diff --git a/sys/compat/freebsd32/freebsd32_misc.c b/sys/compat/freebsd32/freebsd32_misc.c --- a/sys/compat/freebsd32/freebsd32_misc.c +++ b/sys/compat/freebsd32/freebsd32_misc.c @@ -1032,6 +1032,9 @@ r.pc.pc_limit = PAIR32TO64(off_t, r32.pc.pc_limit); data = sizeof(r.pc); break; + case PT_GET_SC_ARGS_ALL: + error = EINVAL; + break; default: addr = uap->addr; break; diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c --- a/sys/kern/sys_process.c +++ b/sys/kern/sys_process.c @@ -527,6 +527,9 @@ else error = copyin(uap->addr, &r.pc, uap->data); break; + case PT_GET_SC_ARGS_ALL: + error = EINVAL; + break; default: addr = uap->addr; break; @@ -708,6 +711,7 @@ case PT_SET_EVENT_MASK: case PT_DETACH: case PT_GET_SC_ARGS: + case PT_GET_SC_ARGS_ALL: sx_xlock(&proctree_lock); proctree_locked = true; break; @@ -1011,6 +1015,19 @@ sizeof(register_t)); break; + case PT_GET_SC_ARGS_ALL: + CTR1(KTR_PTRACE, "PT_GET_SC_ARGS_ALL: pid %d", p->p_pid); + if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) == 0 +#ifdef COMPAT_FREEBSD32 + || (wrap32 && !safe) +#endif + ) { + error = EINVAL; + break; + } + bcopy(td2->td_sa.args, addr, sizeof(td2->td_sa.args)); + break; + case PT_GET_SC_RET: if ((td2->td_dbgflags & (TDB_SCX)) == 0 #ifdef COMPAT_FREEBSD32 diff --git a/sys/sys/ptrace.h b/sys/sys/ptrace.h --- a/sys/sys/ptrace.h +++ b/sys/sys/ptrace.h @@ -86,6 +86,10 @@ #define PT_VM_TIMESTAMP 40 /* Get VM version (timestamp) */ #define PT_VM_ENTRY 41 /* Get VM map (entry) */ +#ifdef _KERNEL +#define PT_GET_SC_ARGS_ALL 42 /* Used by linux(4) */ +#endif + #define PT_FIRSTMACH 64 /* for machine-specific requests */ #include /* machine-specific requests, if any */