afl: Fix afl-qemu build by applying new patches

These patches are gathered from different sources,
such as https://patchwork.kernel.org/patch/10862231/ for the
`gettid` patch.
Another patch comes from the issue in the AFL repository.
The ultimate goal is to get these patches upstream as well,
so we don't keep these general patches only within nixos.

A PR is created against Google/AFL
https://github.com/google/AFL/pull/79,
but it might take a while before it's landed, considering the history
of the project (there are more PRs open).

ZHF: #80379

Fixes issue #82232

pkgs/tools/security/afl/qemu-patches/syscall-glibc2_30.diff

@@ -0,0 +1,51 @@
+--- qemu-2.10.0-clean/linux-user/syscall.c	2020-03-12 18:47:47.898592169 +0100
++++ qemu-2.10.0/linux-user/syscall.c	2020-03-13 09:13:42.461809699 +0100
+@@ -34,6 +34,7 @@
+ #include <sys/resource.h>
+ #include <sys/swap.h>
+ #include <linux/capability.h>
++#include <linux/sockios.h> // https://lkml.org/lkml/2019/6/3/988
+ #include <sched.h>
+ #include <sys/timex.h>
+ #ifdef __ia64__
+@@ -256,7 +257,9 @@ static type name (type1 arg1,type2 arg2,
+ #endif
+ 
+ #ifdef __NR_gettid
+-_syscall0(int, gettid)
++// taken from https://patchwork.kernel.org/patch/10862231/
++#define __NR_sys_gettid __NR_gettid
++_syscall0(int, sys_gettid)
+ #else
+ /* This is a replacement for the host gettid() and must return a host
+    errno. */
+@@ -6219,7 +6222,7 @@ static void *clone_func(void *arg)
+     cpu = ENV_GET_CPU(env);
+     thread_cpu = cpu;
+     ts = (TaskState *)cpu->opaque;
+-    info->tid = gettid();
++    info->tid = sys_gettid();
+     task_settid(ts);
+     if (info->child_tidptr)
+         put_user_u32(info->tid, info->child_tidptr);
+@@ -6363,9 +6366,9 @@ static int do_fork(CPUArchState *env, un
+                mapping.  We can't repeat the spinlock hack used above because
+                the child process gets its own copy of the lock.  */
+             if (flags & CLONE_CHILD_SETTID)
+-                put_user_u32(gettid(), child_tidptr);
++                put_user_u32(sys_gettid(), child_tidptr);
+             if (flags & CLONE_PARENT_SETTID)
+-                put_user_u32(gettid(), parent_tidptr);
++                put_user_u32(sys_gettid(), parent_tidptr);
+             ts = (TaskState *)cpu->opaque;
+             if (flags & CLONE_SETTLS)
+                 cpu_set_tls (env, newtls);
+@@ -11402,7 +11405,7 @@ abi_long do_syscall(void *cpu_env, int n
+         break;
+ #endif
+     case TARGET_NR_gettid:
+-        ret = get_errno(gettid());
++        ret = get_errno(sys_gettid());
+         break;
+ #ifdef TARGET_NR_readahead
+     case TARGET_NR_readahead:

pkgs/tools/security/afl/qemu.nix

@@ -52,6 +52,8 @@ stdenv.mkDerivation {
     "../${afl.src.name}/qemu_mode/patches/memfd.diff"
     # nix-specific patches to make installation more well-behaved
     ./qemu-patches/no-etc-install.patch
+    # patch for fixing qemu build on glibc >= 2.30
+    ./qemu-patches/syscall-glibc2_30.diff
   ];
 
   configureFlags =