[fix] fix cromfs read out of mem range (#9197)

zhuzhuzhus · web-flow · commit 4ad194bb4710 · 2024-07-17T09:08:10.000+08:00
Update dfs_cromfs.c
diff --git a/components/dfs/dfs_v2/filesystems/cromfs/dfs_cromfs.c b/components/dfs/dfs_v2/filesystems/cromfs/dfs_cromfs.c
@@ -786,18 +786,18 @@ static ssize_t dfs_cromfs_read(struct dfs_file *file, void *buf, size_t count, o
     rt_err_t result = RT_EOK;
     file_info *fi = NULL;
     cromfs_info *ci = NULL;
-    uint32_t length = 0;
+    ssize_t length = 0;
 
     ci = (cromfs_info *)file->dentry->mnt->data;
     fi = (file_info *)file->vnode->data;
 
-    if (count < file->vnode->size - *pos)
+    if ((off_t)count < (off_t)file->vnode->size - *pos)
     {
         length = count;
     }
     else
     {
-        length = file->vnode->size - *pos;
+        length = (off_t)file->vnode->size - *pos;
     }
 
     if (length > 0)

Original file line number	Diff line number	Diff line change
`@@ -786,18 +786,18 @@ static ssize_t dfs_cromfs_read(struct dfs_file file, void buf, size_t count, o`
`786`	`786`	`rt_err_t result = RT_EOK;`
`787`	`787`	`file_info *fi = NULL;`
`788`	`788`	`cromfs_info *ci = NULL;`
`789`		`- uint32_t length = 0;`
	`789`	`+ ssize_t length = 0;`
`790`	`790`
`791`	`791`	`ci = (cromfs_info *)file->dentry->mnt->data;`
`792`	`792`	`fi = (file_info *)file->vnode->data;`
`793`	`793`
`794`		`- if (count < file->vnode->size - *pos)`
	`794`	`+ if ((off_t)count < (off_t)file->vnode->size - *pos)`
`795`	`795`	`{`
`796`	`796`	`length = count;`
`797`	`797`	`}`
`798`	`798`	`else`
`799`	`799`	`{`
`800`		`- length = file->vnode->size - *pos;`
	`800`	`+ length = (off_t)file->vnode->size - *pos;`
`801`	`801`	`}`
`802`	`802`
`803`	`803`	`if (length > 0)`