From acb9f95a7c6fda1e488e117af582d5c7db7a218e Mon Sep 17 00:00:00 2001 From: Julio Faracco Date: Mon, 2 Mar 2020 17:13:20 -0300 Subject: [PATCH] i386: Fix GCC warning with snprintf when HAX is enabled MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When HAX is enabled (--enable-hax), GCC 9.2.1 reports issues with snprintf(). Replacing old snprintf() by g_strdup_printf() fixes the problem with boundary checks of vm_id and vcpu_id and finally the warnings produced by GCC. For more details, one example of warning: CC i386-softmmu/target/i386/hax-posix.o qemu/target/i386/hax-posix.c: In function ‘hax_host_open_vm’: qemu/target/i386/hax-posix.c:124:56: error: ‘%02d’ directive output may be truncated writing between 2 and 11 bytes into a region of size 3 [-Werror=format-truncation=] 124 | snprintf(name, sizeof HAX_VM_DEVFS, "/dev/hax_vm/vm%02d", vm_id); | ^~~~ qemu/target/i386/hax-posix.c:124:41: note: directive argument in the range [-2147483648, 64] 124 | snprintf(name, sizeof HAX_VM_DEVFS, "/dev/hax_vm/vm%02d", vm_id); | ^~~~~~~~~~~~~~~~~~~~ In file included from /usr/include/stdio.h:867, from qemu/include/qemu/osdep.h:99, from qemu/target/i386/hax-posix.c:14: /usr/include/bits/stdio2.h:67:10: note: ‘__builtin___snprintf_chk’ output between 17 and 26 bytes into a destination of size 17 67 | return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 68 | __bos (__s), __fmt, __va_arg_pack ()); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Julio Faracco Signed-off-by: Paolo Bonzini --- target/i386/hax-posix.c | 33 ++------------------------------- target/i386/hax-windows.c | 33 ++------------------------------- 2 files changed, 4 insertions(+), 62 deletions(-) diff --git a/target/i386/hax-posix.c b/target/i386/hax-posix.c index a5426a6dac..3bad89f133 100644 --- a/target/i386/hax-posix.c +++ b/target/i386/hax-posix.c @@ -108,41 +108,12 @@ int hax_mod_version(struct hax_state *hax, struct hax_module_version *version) static char *hax_vm_devfs_string(int vm_id) { - char *name; - - if (vm_id > MAX_VM_ID) { - fprintf(stderr, "Too big VM id\n"); - return NULL; - } - -#define HAX_VM_DEVFS "/dev/hax_vm/vmxx" - name = g_strdup(HAX_VM_DEVFS); - if (!name) { - return NULL; - } - - snprintf(name, sizeof HAX_VM_DEVFS, "/dev/hax_vm/vm%02d", vm_id); - return name; + return g_strdup_printf("/dev/hax_vm/vm%02d", vm_id); } static char *hax_vcpu_devfs_string(int vm_id, int vcpu_id) { - char *name; - - if (vm_id > MAX_VM_ID || vcpu_id > MAX_VCPU_ID) { - fprintf(stderr, "Too big vm id %x or vcpu id %x\n", vm_id, vcpu_id); - return NULL; - } - -#define HAX_VCPU_DEVFS "/dev/hax_vmxx/vcpuxx" - name = g_strdup(HAX_VCPU_DEVFS); - if (!name) { - return NULL; - } - - snprintf(name, sizeof HAX_VCPU_DEVFS, "/dev/hax_vm%02d/vcpu%02d", - vm_id, vcpu_id); - return name; + return g_strdup_printf("/dev/hax_vm%02d/vcpu%02d", vm_id, vcpu_id); } int hax_host_create_vm(struct hax_state *hax, int *vmid) diff --git a/target/i386/hax-windows.c b/target/i386/hax-windows.c index 5729ad9b48..0ba488c468 100644 --- a/target/i386/hax-windows.c +++ b/target/i386/hax-windows.c @@ -185,41 +185,12 @@ int hax_mod_version(struct hax_state *hax, struct hax_module_version *version) static char *hax_vm_devfs_string(int vm_id) { - char *name; - - if (vm_id > MAX_VM_ID) { - fprintf(stderr, "Too big VM id\n"); - return NULL; - } - -#define HAX_VM_DEVFS "\\\\.\\hax_vmxx" - name = g_strdup(HAX_VM_DEVFS); - if (!name) { - return NULL; - } - - snprintf(name, sizeof HAX_VM_DEVFS, "\\\\.\\hax_vm%02d", vm_id); - return name; + return g_strdup_printf("/dev/hax_vm/vm%02d", vm_id); } static char *hax_vcpu_devfs_string(int vm_id, int vcpu_id) { - char *name; - - if (vm_id > MAX_VM_ID || vcpu_id > MAX_VCPU_ID) { - fprintf(stderr, "Too big vm id %x or vcpu id %x\n", vm_id, vcpu_id); - return NULL; - } - -#define HAX_VCPU_DEVFS "\\\\.\\hax_vmxx_vcpuxx" - name = g_strdup(HAX_VCPU_DEVFS); - if (!name) { - return NULL; - } - - snprintf(name, sizeof HAX_VCPU_DEVFS, "\\\\.\\hax_vm%02d_vcpu%02d", - vm_id, vcpu_id); - return name; + return g_strdup_printf("/dev/hax_vm%02d/vcpu%02d", vm_id, vcpu_id); } int hax_host_create_vm(struct hax_state *hax, int *vmid) -- 2.11.0