seccomp: fix errno

1 files changed, 25 insertions, 6 deletions

diff --git a/src/fseccomp/syscall.c b/src/fseccomp/syscall.c
index 08ae5953d..8afa3f63d 100644
--- a/src/fseccomp/syscall.c
+++ b/src/fseccomp/syscall.c
@@ -492,10 +492,15 @@ int syscall_check_list(const char *slist, void (*callback)(int fd, int syscall,
                                         fprintf(stderr, "Warning fseccomp: syscall \"%s\" not available on this platform\n", ptr);
                         }
                         else if (callback != NULL) {
-                                if (error_nr != -1)
+                                if (error_nr != -1 && fd != 0) {
                                         filter_add_errno(fd, syscall_nr, error_nr, ptrarg);
-                                else
+                                }
+                                else if (error_nr != -1 && fd == 0) {
+                                        callback(fd, syscall_nr, error_nr, ptrarg);
+                                }
+                                else {
                                         callback(fd, syscall_nr, arg, ptrarg);
+                                }
                         }
                 }
                 ptr = strtok_r(NULL, ",", &saveptr);
@@ -523,20 +528,34 @@ static void syscall_in_list(int fd, int syscall, int arg, void *ptrarg) {
         sl.syscall = syscall;
         syscall_check_list(ptr->slist, find_syscall, fd, 0, &sl);
         // if found in the problem list, add to post-exec list
-        if (sl.found)
+        if (sl.found) {
                 if (ptr->postlist) {
                         if (asprintf(&ptr->postlist, "%s,%s", ptr->postlist, syscall_find_nr(syscall)) == -1)
                                 errExit("asprintf");
                 }
                 else
                         ptr->postlist = strdup(syscall_find_nr(syscall));
-        else // no problem, add to pre-exec list
+        }
+        else { // no problem, add to pre-exec list
+                // build syscall:error_no
+                char *newcall;
+                if (arg != 0) {
+                        if (asprintf(&newcall, "%s:%s", syscall_find_nr(syscall), errno_find_nr(arg)) == -1)
+                                errExit("asprintf");
+                }
+                else {
+                        newcall = strdup(syscall_find_nr(syscall));
+                        if (!newcall)
+                                errExit("strdup");
+                }
+
                 if (ptr->prelist) {
-                        if (asprintf(&ptr->prelist, "%s,%s", ptr->prelist, syscall_find_nr(syscall)) == -1)
+                        if (asprintf(&ptr->prelist, "%s,%s", ptr->prelist, newcall) == -1)
                                 errExit("asprintf");
                 }
                 else
-                        ptr->prelist = strdup(syscall_find_nr(syscall));
+                        ptr->prelist = newcall;
+        }
 }
 
 // go through list and find matches for syscalls in list @default-keep