linux-user: allocate heap memory for execve arguments
Arguments passed to execve(2) call from user program could
be large, allocating stack memory for them via alloca(3) call
would lead to bad behaviour. Use 'g_new0' to allocate memory
for such arguments.
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 32aba19..c8f6efc 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -7985,8 +7985,8 @@
envc++;
}
- argp = alloca((argc + 1) * sizeof(void *));
- envp = alloca((envc + 1) * sizeof(void *));
+ argp = g_new0(char *, argc + 1);
+ envp = g_new0(char *, envc + 1);
for (gp = guest_argp, q = argp; gp;
gp += sizeof(abi_ulong), q++) {
@@ -8047,6 +8047,9 @@
break;
unlock_user(*q, addr, 0);
}
+
+ g_free(argp);
+ g_free(envp);
}
break;
case TARGET_NR_chdir:
