https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=98669a24760a84bfef498fedeef7fa7ecc518e6c
commit 98669a24760a84bfef498fedeef7fa7ecc518e6c Author: Corinna Vinschen <[email protected]> Date: Tue Aug 6 10:46:31 2019 +0200 Cygwin: exec: check execute bit prior to evaluating script When the exec family of functions is called for a script-like file, the av::setup function handles the exec[vl]p case as well. The execve case for files not starting with a she-bang is handled first by returning ENOEXEC. Only after that, the file's executability is checked. This leads to the problem that ENOEXEC is returned for non-executable files as well. A calling shell interprets this as a file it should try to run as script. This is not desired for non-executable files. Fix this problem by checking the file for executability first. Only after that, follow the other potential code paths. Signed-off-by: Corinna Vinschen <[email protected]> Diff: --- winsup/cygwin/spawn.cc | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/winsup/cygwin/spawn.cc b/winsup/cygwin/spawn.cc index 7f7af44..d957728 100644 --- a/winsup/cygwin/spawn.cc +++ b/winsup/cygwin/spawn.cc @@ -1172,6 +1172,12 @@ av::setup (const char *prog_arg, path_conv& real_path, const char *ext, } UnmapViewOfFile (buf); just_shell: + /* Check if script is executable. Otherwise we start non-executable + scripts successfully, which is incorrect behaviour. */ + if (real_path.has_acls () + && check_file_access (real_path, X_OK, true) < 0) + return -1; /* errno is already set. */ + if (!pgm) { if (!p_type_exec) @@ -1188,12 +1194,6 @@ av::setup (const char *prog_arg, path_conv& real_path, const char *ext, arg1 = NULL; } - /* Check if script is executable. Otherwise we start non-executable - scripts successfully, which is incorrect behaviour. */ - if (real_path.has_acls () - && check_file_access (real_path, X_OK, true) < 0) - return -1; /* errno is already set. */ - /* Replace argv[0] with the full path to the script if this is the first time through the loop. */ replace0_maybe (prog_arg);
