diff mbox series

[MINIOS,v3,2/5] reset file type in close() in one place only

Message ID 20220116064527.23519-3-jgross@suse.com (mailing list archive)
State New, archived
Headers show
Series mini-os: remove struct file dependency on config | expand

Commit Message

Jürgen Groß Jan. 16, 2022, 6:45 a.m. UTC 
Today the file type in struct file is set to FTYPE_NONE for each
file type individually. Do that at the end of close() handling for
all types.

While at it wipe the complete struct file, too, in order to avoid
old data creeping into a new allocated struct file.

Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- new patch
V3:
- add error handling (Andrew Cooper)
- use BUILD_BUG_ON() (Andrew Cooper)
---
 lib/sys.c | 56 ++++++++++++++++++++++++++++---------------------------
 lib/xs.c  |  1 -
 2 files changed, 29 insertions(+), 28 deletions(-)

Comments

Samuel Thibault Jan. 16, 2022, 8:33 p.m. UTC | #1 
Juergen Gross, le dim. 16 janv. 2022 07:45:24 +0100, a ecrit:
> Today the file type in struct file is set to FTYPE_NONE for each
> file type individually. Do that at the end of close() handling for
> all types.
> 
> While at it wipe the complete struct file, too, in order to avoid
> old data creeping into a new allocated struct file.
> 
> Signed-off-by: Juergen Gross <jgross@suse.com>

Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

> ---
> V2:
> - new patch
> V3:
> - add error handling (Andrew Cooper)
> - use BUILD_BUG_ON() (Andrew Cooper)
> ---
>  lib/sys.c | 56 ++++++++++++++++++++++++++++---------------------------
>  lib/xs.c  |  1 -
>  2 files changed, 29 insertions(+), 28 deletions(-)
> 
> diff --git a/lib/sys.c b/lib/sys.c
> index 9a03875c..7df77cc6 100644
> --- a/lib/sys.c
> +++ b/lib/sys.c
> @@ -265,7 +265,7 @@ int read(int fd, void *buf, size_t nbytes)
>              return ret;
>          }
>  #ifdef HAVE_LWIP
> -	case FTYPE_SOCKET:
> +        case FTYPE_SOCKET:
>  	    return lwip_read(files[fd].fd, buf, nbytes);
>  #endif
>  #ifdef CONFIG_NETFRONT
> @@ -424,84 +424,86 @@ int fsync(int fd) {
>  
>  int close(int fd)
>  {
> +    int res = 0;
> +
> +    if ( fd < 0 || fd >= ARRAY_SIZE(files) )
> +        goto error;
> +
>      printk("close(%d)\n", fd);
>      switch (files[fd].type) {
>          default:
> -	    files[fd].type = FTYPE_NONE;
> -	    return 0;
> +            break;
>  #ifdef CONFIG_XENBUS
>  	case FTYPE_XENBUS:
>              xs_daemon_close((void*)(intptr_t) fd);
> -            return 0;
> +            break;
>  #endif
>  #ifdef HAVE_LWIP
> -	case FTYPE_SOCKET: {
> -	    int res = lwip_close(files[fd].fd);
> -	    files[fd].type = FTYPE_NONE;
> -	    return res;
> -	}
> +	case FTYPE_SOCKET:
> +            res = lwip_close(files[fd].fd);
> +            break;
>  #endif
>  #ifdef CONFIG_LIBXENCTRL
>  	case FTYPE_XC:
>  	    minios_interface_close_fd(fd);
> -	    return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_LIBXENEVTCHN
>  	case FTYPE_EVTCHN:
>  	    minios_evtchn_close_fd(fd);
> -            return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_LIBXENGNTTAB
>  	case FTYPE_GNTMAP:
>  	    minios_gnttab_close_fd(fd);
> -	    return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_NETFRONT
>  	case FTYPE_TAP:
>  	    shutdown_netfront(files[fd].dev);
> -	    files[fd].type = FTYPE_NONE;
> -	    return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_BLKFRONT
>  	case FTYPE_BLK:
>              shutdown_blkfront(files[fd].dev);
> -	    files[fd].type = FTYPE_NONE;
> -	    return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_TPMFRONT
>  	case FTYPE_TPMFRONT:
>              shutdown_tpmfront(files[fd].dev);
> -	    files[fd].type = FTYPE_NONE;
> -	    return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_TPM_TIS
>  	case FTYPE_TPM_TIS:
>              shutdown_tpm_tis(files[fd].dev);
> -	    files[fd].type = FTYPE_NONE;
> -	    return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_KBDFRONT
>  	case FTYPE_KBD:
>              shutdown_kbdfront(files[fd].dev);
> -            files[fd].type = FTYPE_NONE;
> -            return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_FBFRONT
>  	case FTYPE_FB:
>              shutdown_fbfront(files[fd].dev);
> -            files[fd].type = FTYPE_NONE;
> -            return 0;
> +            break;
>  #endif
>  #ifdef CONFIG_CONSFRONT
>          case FTYPE_SAVEFILE:
>          case FTYPE_CONSOLE:
>              fini_consfront(files[fd].dev);
> -            files[fd].type = FTYPE_NONE;
> -            return 0;
> +            break;
>  #endif
>  	case FTYPE_NONE:
> -	    break;
> +            goto error;
>      }
> +
> +    memset(files + fd, 0, sizeof(struct file));
> +    BUILD_BUG_ON(FTYPE_NONE != 0);
> +
> +    return res;
> +
> + error:
>      printk("close(%d): Bad descriptor\n", fd);
>      errno = EBADF;
>      return -1;
> diff --git a/lib/xs.c b/lib/xs.c
> index 0459f52f..4af0f960 100644
> --- a/lib/xs.c
> +++ b/lib/xs.c
> @@ -35,7 +35,6 @@ void xs_daemon_close(struct xs_handle *h)
>          next = event->next;
>          free(event);
>      }
> -    files[fd].type = FTYPE_NONE;
>  }
>  
>  int xs_fileno(struct xs_handle *h)
> -- 
> 2.26.2
>
diff mbox series

Patch

diff --git a/lib/sys.c b/lib/sys.c
index 9a03875c..7df77cc6 100644
--- a/lib/sys.c
+++ b/lib/sys.c
@@ -265,7 +265,7 @@  int read(int fd, void *buf, size_t nbytes)
             return ret;
         }
 #ifdef HAVE_LWIP
-	case FTYPE_SOCKET:
+        case FTYPE_SOCKET:
 	    return lwip_read(files[fd].fd, buf, nbytes);
 #endif
 #ifdef CONFIG_NETFRONT
@@ -424,84 +424,86 @@  int fsync(int fd) {
 
 int close(int fd)
 {
+    int res = 0;
+
+    if ( fd < 0 || fd >= ARRAY_SIZE(files) )
+        goto error;
+
     printk("close(%d)\n", fd);
     switch (files[fd].type) {
         default:
-	    files[fd].type = FTYPE_NONE;
-	    return 0;
+            break;
 #ifdef CONFIG_XENBUS
 	case FTYPE_XENBUS:
             xs_daemon_close((void*)(intptr_t) fd);
-            return 0;
+            break;
 #endif
 #ifdef HAVE_LWIP
-	case FTYPE_SOCKET: {
-	    int res = lwip_close(files[fd].fd);
-	    files[fd].type = FTYPE_NONE;
-	    return res;
-	}
+	case FTYPE_SOCKET:
+            res = lwip_close(files[fd].fd);
+            break;
 #endif
 #ifdef CONFIG_LIBXENCTRL
 	case FTYPE_XC:
 	    minios_interface_close_fd(fd);
-	    return 0;
+            break;
 #endif
 #ifdef CONFIG_LIBXENEVTCHN
 	case FTYPE_EVTCHN:
 	    minios_evtchn_close_fd(fd);
-            return 0;
+            break;
 #endif
 #ifdef CONFIG_LIBXENGNTTAB
 	case FTYPE_GNTMAP:
 	    minios_gnttab_close_fd(fd);
-	    return 0;
+            break;
 #endif
 #ifdef CONFIG_NETFRONT
 	case FTYPE_TAP:
 	    shutdown_netfront(files[fd].dev);
-	    files[fd].type = FTYPE_NONE;
-	    return 0;
+            break;
 #endif
 #ifdef CONFIG_BLKFRONT
 	case FTYPE_BLK:
             shutdown_blkfront(files[fd].dev);
-	    files[fd].type = FTYPE_NONE;
-	    return 0;
+            break;
 #endif
 #ifdef CONFIG_TPMFRONT
 	case FTYPE_TPMFRONT:
             shutdown_tpmfront(files[fd].dev);
-	    files[fd].type = FTYPE_NONE;
-	    return 0;
+            break;
 #endif
 #ifdef CONFIG_TPM_TIS
 	case FTYPE_TPM_TIS:
             shutdown_tpm_tis(files[fd].dev);
-	    files[fd].type = FTYPE_NONE;
-	    return 0;
+            break;
 #endif
 #ifdef CONFIG_KBDFRONT
 	case FTYPE_KBD:
             shutdown_kbdfront(files[fd].dev);
-            files[fd].type = FTYPE_NONE;
-            return 0;
+            break;
 #endif
 #ifdef CONFIG_FBFRONT
 	case FTYPE_FB:
             shutdown_fbfront(files[fd].dev);
-            files[fd].type = FTYPE_NONE;
-            return 0;
+            break;
 #endif
 #ifdef CONFIG_CONSFRONT
         case FTYPE_SAVEFILE:
         case FTYPE_CONSOLE:
             fini_consfront(files[fd].dev);
-            files[fd].type = FTYPE_NONE;
-            return 0;
+            break;
 #endif
 	case FTYPE_NONE:
-	    break;
+            goto error;
     }
+
+    memset(files + fd, 0, sizeof(struct file));
+    BUILD_BUG_ON(FTYPE_NONE != 0);
+
+    return res;
+
+ error:
     printk("close(%d): Bad descriptor\n", fd);
     errno = EBADF;
     return -1;
diff --git a/lib/xs.c b/lib/xs.c
index 0459f52f..4af0f960 100644
--- a/lib/xs.c
+++ b/lib/xs.c
@@ -35,7 +35,6 @@  void xs_daemon_close(struct xs_handle *h)
         next = event->next;
         free(event);
     }
-    files[fd].type = FTYPE_NONE;
 }
 
 int xs_fileno(struct xs_handle *h)