[PATCH v2 01/11] linux-user: handle /proc/self/exe for execve

[YAMAMOTO Takashi <yamamoto@midokura.com>]

It seems somehow common to execve /proc/self/exe in docker
or golang community these days.
At least, moby "reexec" and runc "libcontainer" do that.

Signed-off-by: YAMAMOTO Takashi <yamamoto@midokura.com>
---
 linux-user/syscall.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index c9f812091c..a2b03ecb8b 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -8470,6 +8470,7 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
 #endif
     case TARGET_NR_execve:
         {
+            const char *path;
             char **argp, **envp;
             int argc, envc;
             abi_ulong gp;
@@ -8537,7 +8538,11 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
              * before the execve completes and makes it the other
              * program's problem.
              */
-            ret = get_errno(safe_execve(p, argp, envp));
+            path = p;
+            if (is_proc_myself(path, "exe")) {
+                path = exec_path;
+            }
+            ret = get_errno(safe_execve(path, argp, envp));
             unlock_user(p, arg1, 0);
 
             goto execve_end;
-- 
2.21.1 (Apple Git-122.3)