References: https://gitlab.com/qemu-project/qemu/-/issues/1007
Signed-off-by: Drew DeVault <s...@cmpwn.com>
---
linux-user/syscall.c | 204 +++++++++++++++++++++++--------------------
1 file changed, 111 insertions(+), 93 deletions(-)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index f55cdebee5..57f0b2f0e8 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -633,7 +633,12 @@ safe_syscall4(pid_t, wait4, pid_t, pid, int *, status,
int, options, \
#endif
safe_syscall5(int, waitid, idtype_t, idtype, id_t, id, siginfo_t *, infop, \
int, options, struct rusage *, rusage)
+#if defined(TARGET_NR_execveat)
+safe_syscall5(int, execveat, int, dirfd, const char *, filename,
+ char **, argv, char **, envp, int, flags)
+#else
safe_syscall3(int, execve, const char *, filename, char **, argv, char **,
envp)
+#endif
#if defined(TARGET_NR_select) || defined(TARGET_NR__newselect) || \
defined(TARGET_NR_pselect6) || defined(TARGET_NR_pselect6_time64)
safe_syscall6(int, pselect6, int, nfds, fd_set *, readfds, fd_set *, writefds,
\
@@ -8281,6 +8286,107 @@ static int do_openat(CPUArchState *cpu_env, int dirfd,
const char *pathname, int
return safe_openat(dirfd, path(pathname), flags, mode);
}
+static int do_execveat(CPUArchState *cpu_env, int dirfd, abi_long pathname,
abi_long guest_argp, abi_long guest_envp, int flags)
+{
+ int ret;
+ char **argp, **envp;
+ int argc, envc;
+ abi_ulong gp;
+ abi_ulong addr;
+ char **q;
+ void *p;
+
+ argc = 0;
+
+ for (gp = guest_argp; gp; gp += sizeof(abi_ulong)) {
+ if (get_user_ual(addr, gp))
+ return -TARGET_EFAULT;
+ if (!addr)
+ break;
+ argc++;
+ }
+ envc = 0;
+ for (gp = guest_envp; gp; gp += sizeof(abi_ulong)) {
+ if (get_user_ual(addr, gp))
+ return -TARGET_EFAULT;
+ if (!addr)
+ break;
+ envc++;
+ }
+
+ argp = g_new0(char *, argc + 1);
+ envp = g_new0(char *, envc + 1);
+
+ for (gp = guest_argp, q = argp; gp;
+ gp += sizeof(abi_ulong), q++) {
+ if (get_user_ual(addr, gp))
+ goto execve_efault;
+ if (!addr)
+ break;
+ if (!(*q = lock_user_string(addr)))
+ goto execve_efault;
+ }
+ *q = NULL;
+
+ for (gp = guest_envp, q = envp; gp;
+ gp += sizeof(abi_ulong), q++) {
+ if (get_user_ual(addr, gp))
+ goto execve_efault;
+ if (!addr)
+ break;
+ if (!(*q = lock_user_string(addr)))
+ goto execve_efault;
+ }
+ *q = NULL;
+
+ /* Although execve() is not an interruptible syscall it is
+ * a special case where we must use the safe_syscall wrapper:
+ * if we allow a signal to happen before we make the host
+ * syscall then we will 'lose' it, because at the point of
+ * execve the process leaves QEMU's control. So we use the
+ * safe syscall wrapper to ensure that we either take the
+ * signal as a guest signal, or else it does not happen
+ * before the execve completes and makes it the other
+ * program's problem.
+ */
+ if (!(p = lock_user_string(pathname)))
+ goto execve_efault;
+
+#if defined(TARGET_NR_execveat)
+ ret = get_errno(safe_execveat(dirfd, p, argp, envp, flags));
+#else
+ assert(dirfd == AT_FDCWD && flags == 0);
+ ret = get_errno(safe_execve(p, argp, envp));
+#endif
+
+ unlock_user(p, pathname, 0);
+
+ goto execve_end;
+
+execve_efault:
+ ret = -TARGET_EFAULT;
+
+execve_end:
+ for (gp = guest_argp, q = argp; *q;
+ gp += sizeof(abi_ulong), q++) {
+ if (get_user_ual(addr, gp)
+ || !addr)
+ break;
+ unlock_user(*q, addr, 0);
+ }
+ for (gp = guest_envp, q = envp; *q;
+ gp += sizeof(abi_ulong), q++) {
+ if (get_user_ual(addr, gp)
+ || !addr)
+ break;
+ unlock_user(*q, addr, 0);
+ }
+
+ g_free(argp);
+ g_free(envp);
+ return ret;
+}
+
#define TIMER_MAGIC 0x0caf0000
#define TIMER_MAGIC_MASK 0xffff0000
@@ -8748,101 +8854,13 @@ static abi_long do_syscall1(CPUArchState *cpu_env, int
num, abi_long arg1,
ret = get_errno(unlinkat(arg1, p, arg3));
unlock_user(p, arg2, 0);
return ret;
+#endif
+#if defined(TARGET_NR_execveat)
+ case TARGET_NR_execveat:
+ return do_execveat(cpu_env, arg1, arg2, arg3, arg4, arg5);
#endif
case TARGET_NR_execve:
- {
- char **argp, **envp;
- int argc, envc;
- abi_ulong gp;
- abi_ulong guest_argp;
- abi_ulong guest_envp;
- abi_ulong addr;
- char **q;
-
- argc = 0;
- guest_argp = arg2;
- for (gp = guest_argp; gp; gp += sizeof(abi_ulong)) {
- if (get_user_ual(addr, gp))
- return -TARGET_EFAULT;
- if (!addr)
- break;
- argc++;
- }
- envc = 0;
- guest_envp = arg3;
- for (gp = guest_envp; gp; gp += sizeof(abi_ulong)) {
- if (get_user_ual(addr, gp))
- return -TARGET_EFAULT;
- if (!addr)
- break;
- envc++;
- }
-
- argp = g_new0(char *, argc + 1);
- envp = g_new0(char *, envc + 1);
-
- for (gp = guest_argp, q = argp; gp;
- gp += sizeof(abi_ulong), q++) {
- if (get_user_ual(addr, gp))
- goto execve_efault;
- if (!addr)
- break;
- if (!(*q = lock_user_string(addr)))
- goto execve_efault;
- }
- *q = NULL;
-
- for (gp = guest_envp, q = envp; gp;
- gp += sizeof(abi_ulong), q++) {
- if (get_user_ual(addr, gp))
- goto execve_efault;
- if (!addr)
- break;
- if (!(*q = lock_user_string(addr)))
- goto execve_efault;
- }
- *q = NULL;
-
- if (!(p = lock_user_string(arg1)))
- goto execve_efault;
- /* Although execve() is not an interruptible syscall it is
- * a special case where we must use the safe_syscall wrapper:
- * if we allow a signal to happen before we make the host
- * syscall then we will 'lose' it, because at the point of
- * execve the process leaves QEMU's control. So we use the
- * safe syscall wrapper to ensure that we either take the
- * signal as a guest signal, or else it does not happen
- * before the execve completes and makes it the other
- * program's problem.
- */
- ret = get_errno(safe_execve(p, argp, envp));
- unlock_user(p, arg1, 0);
-
- goto execve_end;
-
- execve_efault:
- ret = -TARGET_EFAULT;
-
- execve_end:
- for (gp = guest_argp, q = argp; *q;
- gp += sizeof(abi_ulong), q++) {
- if (get_user_ual(addr, gp)
- || !addr)
- break;
- unlock_user(*q, addr, 0);
- }
- for (gp = guest_envp, q = envp; *q;
- gp += sizeof(abi_ulong), q++) {
- if (get_user_ual(addr, gp)
- || !addr)
- break;
- unlock_user(*q, addr, 0);
- }
-
- g_free(argp);
- g_free(envp);
- }
- return ret;
+ return do_execveat(cpu_env, AT_FDCWD, arg1, arg2, arg3, 0);
case TARGET_NR_chdir:
if (!(p = lock_user_string(arg1)))
return -TARGET_EFAULT;
--
2.38.1
