From owner-dev-commits-src-all@freebsd.org Tue Sep 14 20:41:06 2021 Return-Path: Delivered-To: dev-commits-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 5A202670C71; Tue, 14 Sep 2021 20:41:06 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4H8FcL28Z6z3GV6; Tue, 14 Sep 2021 20:41:06 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 29CEF214AD; Tue, 14 Sep 2021 20:41:06 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 18EKf6Hk040963; Tue, 14 Sep 2021 20:41:06 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 18EKf6RU040962; Tue, 14 Sep 2021 20:41:06 GMT (envelope-from git) Date: Tue, 14 Sep 2021 20:41:06 GMT Message-Id: <202109142041.18EKf6RU040962@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Edward Tomasz Napierala Subject: git: bdf0f24bb16d - main - linux: implement PTRACE_GET_SYSCALL_INFO MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: trasz X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: bdf0f24bb16d556a5b1e01cdfc087d08e91ac572 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 Sep 2021 20:41:06 -0000 The branch main has been updated by trasz: URL: https://cgit.FreeBSD.org/src/commit/?id=bdf0f24bb16d556a5b1e01cdfc087d08e91ac572 commit bdf0f24bb16d556a5b1e01cdfc087d08e91ac572 Author: Edward Tomasz Napierala AuthorDate: 2021-09-12 11:31:10 +0000 Commit: Edward Tomasz Napierala CommitDate: 2021-09-14 20:19:55 +0000 linux: implement PTRACE_GET_SYSCALL_INFO This is one of the pieces required to make modern (ie Focal) strace(1) work. Reviewed By: jhb (earlier version) Sponsored by: EPSRC Differential Revision: https://reviews.freebsd.org/D28212 --- lib/libsysdecode/mktables | 2 +- sys/amd64/linux/linux_ptrace.c | 98 +++++++++++++++++++++++++++++++++-- sys/compat/freebsd32/freebsd32_misc.c | 3 ++ sys/kern/sys_process.c | 17 ++++++ sys/sys/ptrace.h | 4 ++ 5 files changed, 120 insertions(+), 4 deletions(-) diff --git a/lib/libsysdecode/mktables b/lib/libsysdecode/mktables index 3d152a3a2646..1c263fd3b0b2 100644 --- a/lib/libsysdecode/mktables +++ b/lib/libsysdecode/mktables @@ -116,7 +116,7 @@ gen_table "nfssvcflags" "NFSSVC_[A-Z0-9]+[[:space:]]+0x[0-9]+" "nfs/ 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 index 3afaded3a203..70e52c528c72 100644 --- a/sys/amd64/linux/linux_ptrace.c +++ b/sys/amd64/linux/linux_ptrace.c @@ -93,6 +93,12 @@ __FBSDID("$FreeBSD$"); 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 @@ struct linux_pt_reg { 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 @@ linux_ptrace_seize(struct thread *td, pid_t pid, l_ulong addr, l_ulong data) } 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 index c417a64d286a..01d772b35ee8 100644 --- a/sys/compat/freebsd32/freebsd32_misc.c +++ b/sys/compat/freebsd32/freebsd32_misc.c @@ -1032,6 +1032,9 @@ freebsd32_ptrace(struct thread *td, struct freebsd32_ptrace_args *uap) 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 index 1b97424c58ca..e2d8042744d0 100644 --- a/sys/kern/sys_process.c +++ b/sys/kern/sys_process.c @@ -527,6 +527,9 @@ sys_ptrace(struct thread *td, struct ptrace_args *uap) 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 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 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 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) 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 index 1e7c1c71056b..066a54f721c8 100644 --- 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 */