Date: Mon, 21 Feb 2022 13:48:53 GMT From: Edward Tomasz Napierala <trasz@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Subject: git: 4cae9d803a95 - stable/13 - Remove PT_GET_SC_ARGS_ALL Message-ID: <202202211348.21LDmrOE091868@gitrepo.freebsd.org>
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The branch stable/13 has been updated by trasz: URL: https://cgit.FreeBSD.org/src/commit/?id=4cae9d803a9562a003d00bf8f7b90674e011bae7 commit 4cae9d803a9562a003d00bf8f7b90674e011bae7 Author: Konstantin Belousov <kib@FreeBSD.org> AuthorDate: 2021-09-15 13:24:09 +0000 Commit: Edward Tomasz Napierala <trasz@FreeBSD.org> CommitDate: 2022-02-21 13:34:16 +0000 Remove PT_GET_SC_ARGS_ALL Reimplement bdf0f24bb16d556a5b by checking for the caller' ABI in the implementation of PT_GET_SC_ARGS, and copying out everything if it is Linuxolator. Also fix a minor information leak: if PT_GET_SC_ARGS_ALL is done on the thread reused after other process, it allows to read some number of that thread last syscall arguments. Clear td_sa.args in thread_alloc(). Reviewed by: jhb Sponsored by: The FreeBSD Foundation Differential revision: https://reviews.freebsd.org/D31968 (cherry picked from commit f575573ca57716395ad88b962388a55d755cf6a7) --- lib/libsysdecode/mktables | 2 +- sys/amd64/linux/linux_ptrace.c | 18 ++++++++++-------- sys/compat/freebsd32/freebsd32_misc.c | 3 --- sys/kern/kern_thread.c | 1 + sys/kern/sys_process.c | 23 ++++------------------- sys/sys/ptrace.h | 4 ---- 6 files changed, 16 insertions(+), 35 deletions(-) diff --git a/lib/libsysdecode/mktables b/lib/libsysdecode/mktables index f044784717c0..77cfa15bd1f5 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" "PT_GET_SC_ARGS_ALL" +gen_table "ptraceop" "PT_[[:alnum:]_]+[[:space:]]+[0-9]+" "sys/ptrace.h" 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 fa400e0d3529..a29a3310dfcd 100644 --- a/sys/amd64/linux/linux_ptrace.c +++ b/sys/amd64/linux/linux_ptrace.c @@ -578,17 +578,19 @@ linux_ptrace_get_syscall_info(struct thread *td, pid_t pid, 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. + * The use of PT_GET_SC_ARGS there is special, + * implementation of PT_GET_SC_ARGS for Linux-ABI + * callers emulates 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, + error = kern_ptrace(td, PT_GET_SC_ARGS, pid, &si.entry.args, sizeof(si.entry.args)); if (error != 0) { - linux_msg(td, "PT_GET_SC_ARGS_ALL failed with error %d", + linux_msg(td, "PT_GET_SC_ARGS failed with error %d", error); return (error); } diff --git a/sys/compat/freebsd32/freebsd32_misc.c b/sys/compat/freebsd32/freebsd32_misc.c index b7128debd97f..e56ab423f538 100644 --- a/sys/compat/freebsd32/freebsd32_misc.c +++ b/sys/compat/freebsd32/freebsd32_misc.c @@ -1025,9 +1025,6 @@ 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/kern_thread.c b/sys/kern/kern_thread.c index 48aac8e057b8..54254112b376 100644 --- a/sys/kern/kern_thread.c +++ b/sys/kern/kern_thread.c @@ -761,6 +761,7 @@ thread_alloc(int pages) return (NULL); } td->td_tid = tid; + bzero(&td->td_sa.args, sizeof(td->td_sa.args)); cpu_thread_alloc(td); EVENTHANDLER_DIRECT_INVOKE(thread_ctor, td); return (td); diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c index 75d950a57057..1b9c00179bda 100644 --- a/sys/kern/sys_process.c +++ b/sys/kern/sys_process.c @@ -532,9 +532,6 @@ 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; @@ -716,7 +713,6 @@ 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; @@ -1016,21 +1012,10 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) break; } bzero(addr, sizeof(td2->td_sa.args)); - bcopy(td2->td_sa.args, addr, td2->td_sa.callp->sy_narg * - 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)); + /* See the explanation in linux_ptrace_get_syscall_info(). */ + bcopy(td2->td_sa.args, addr, SV_PROC_ABI(td->td_proc) == + SV_ABI_LINUX ? sizeof(td2->td_sa.args) : + td2->td_sa.callp->sy_narg * sizeof(register_t)); break; case PT_GET_SC_RET: diff --git a/sys/sys/ptrace.h b/sys/sys/ptrace.h index de7a49576c30..4cd7a3fceaec 100644 --- a/sys/sys/ptrace.h +++ b/sys/sys/ptrace.h @@ -86,10 +86,6 @@ #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/ptrace.h> /* machine-specific requests, if any */
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