From f095b789e609dd7bc80992eacce44fbbe7f6be42 Mon Sep 17 00:00:00 2001
From: Zachary Yedidia <zyedidia@gmail.com>
Date: Fri, 31 Jan 2025 14:38:13 -0800
Subject: [PATCH] Add madvise and getrusage ignored syscalls

---
 liblfi/arch/x64/arch_sys.h  |  2 ++
 liblfi/sys.c                | 26 ++++++++++++++------------
 liblfi/syscalls/meson.build |  1 +
 liblfi/syscalls/sys_none.c  | 16 ++++++++++++++++
 liblfi/syscalls/syscalls.h  |  4 ++++
 5 files changed, 37 insertions(+), 12 deletions(-)
 create mode 100644 liblfi/syscalls/sys_none.c

diff --git a/liblfi/arch/x64/arch_sys.h b/liblfi/arch/x64/arch_sys.h
index 0dfd658..8885131 100644
--- a/liblfi/arch/x64/arch_sys.h
+++ b/liblfi/arch/x64/arch_sys.h
@@ -27,6 +27,7 @@ enum {
     TUX_SYS_access             = 21,
     TUX_SYS_sched_yield        = 24,
     TUX_SYS_mremap             = 25,
+    TUX_SYS_madvise            = 28,
     TUX_SYS_getpid             = 39,
     TUX_SYS_socket             = 41,
     TUX_SYS_clone              = 56,
@@ -52,6 +53,7 @@ enum {
     TUX_SYS_fchown             = 93,
     TUX_SYS_lchown             = 94,
     TUX_SYS_getrlimit          = 97,
+    TUX_SYS_getrusage          = 98,
     TUX_SYS_sysinfo            = 99,
     TUX_SYS_rt_sigpending      = 127,
     TUX_SYS_rt_sigtimedwait    = 128,
diff --git a/liblfi/sys.c b/liblfi/sys.c
index 950a665..91bceca 100644
--- a/liblfi/sys.c
+++ b/liblfi/sys.c
@@ -79,18 +79,20 @@ syshandle(struct TuxThread* p, uintptr_t sysno, uintptr_t a0, uintptr_t a1,
     SYS(sysinfo,           sys_sysinfo(proc, a0))
     SYS(getrlimit,         sys_getrlimit(proc, a0, a1))
     SYS(prctl,             sys_prctl(proc, a0, a1, a2, a3, a4))
-    SYS(set_robust_list,   0)
-    SYS(membarrier,        0)
-    SYS(sigaltstack,       0)
-    SYS(statx,             -TUX_ENOSYS)
-    SYS(rseq,              -TUX_ENOSYS)
-    SYS(prlimit64,         -TUX_ENOSYS)
-    SYS(statfs,            -TUX_ENOSYS)
-    SYS(getxattr,          -TUX_ENOSYS)
-    SYS(lgetxattr,         -TUX_ENOSYS)
-    SYS(socket,            -TUX_ENOSYS)
-    SYS(mremap,            -TUX_ENOSYS)
-    SYS(utimensat,         -TUX_ENOSYS)
+    SYS(set_robust_list,   sys_ignore(proc, "set_robust_list"))
+    SYS(membarrier,        sys_ignore(proc, "membarrier"))
+    SYS(sigaltstack,       sys_ignore(proc, "sigaltstack"))
+    SYS(madvise,           sys_ignore(proc, "madvise"))
+    SYS(getrusage,         sys_ignore(proc, "getrusage"))
+    SYS(statx,             sys_nosys(proc, "statx"))
+    SYS(rseq,              sys_nosys(proc, "rseq"))
+    SYS(prlimit64,         sys_nosys(proc, "prlimit64"))
+    SYS(statfs,            sys_nosys(proc, "statfs"))
+    SYS(getxattr,          sys_nosys(proc, "getxattr"))
+    SYS(lgetxattr,         sys_nosys(proc, "lgetxattr"))
+    SYS(socket,            sys_nosys(proc, "socket"))
+    SYS(mremap,            sys_nosys(proc, "mremap"))
+    SYS(utimensat,         sys_nosys(proc, "utimensat"))
     default:
         fprintf(stderr, "unknown syscall: %ld (%s)\n", sysno, sysname(sysno));
         assert(!"unhandled syscall");
diff --git a/liblfi/syscalls/meson.build b/liblfi/syscalls/meson.build
index 5eea95c..88a46e5 100644
--- a/liblfi/syscalls/meson.build
+++ b/liblfi/syscalls/meson.build
@@ -10,6 +10,7 @@ srcs += files(
   'sys_fcntl.c',
   'sys_cwd.c',
   'sys_prctl.c',
+  'sys_none.c',
   'strace.c',
 )
 
diff --git a/liblfi/syscalls/sys_none.c b/liblfi/syscalls/sys_none.c
new file mode 100644
index 0000000..2c9663e
--- /dev/null
+++ b/liblfi/syscalls/sys_none.c
@@ -0,0 +1,16 @@
+#include "print.h"
+#include "syscalls/syscalls.h"
+
+uintptr_t
+sys_ignore(struct TuxProc* p, const char* name)
+{
+    WARN(p->tux, "%s: ignored", name);
+    return 0;
+}
+
+uintptr_t
+sys_nosys(struct TuxProc* p, const char* name)
+{
+    WARN(p->tux, "%s: unsupported (ENOSYS)", name);
+    return -TUX_ENOSYS;
+}
diff --git a/liblfi/syscalls/syscalls.h b/liblfi/syscalls/syscalls.h
index c65265a..6b0838c 100644
--- a/liblfi/syscalls/syscalls.h
+++ b/liblfi/syscalls/syscalls.h
@@ -178,3 +178,7 @@ int sys_set_tid_address(struct TuxThread* p, uintptr_t ctid);
 int sys_gettid(struct TuxThread* p);
 
 int sys_prctl(struct TuxProc* p, int op, uint64_t arg2, uint64_t arg3, uint64_t arg4, uint64_t arg5);
+
+uintptr_t sys_ignore(struct TuxProc* p, const char* name);
+
+uintptr_t sys_nosys(struct TuxProc* p, const char* name);