From facda5a9cbf535e401be6667c231e5516125145f Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Fri, 15 Jul 2016 12:02:31 +0200 Subject: fs: Check for correct open mode Check that readonly openen files is not written to and writeonly files is not read from. Signed-off-by: Sascha Hauer --- fs/fs.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/fs.c b/fs/fs.c index f63a2dde51..b7e7c63ffe 100644 --- a/fs/fs.c +++ b/fs/fs.c @@ -738,6 +738,11 @@ static ssize_t __read(FILE *f, void *buf, size_t count) struct fs_driver_d *fsdrv; int ret; + if ((f->flags & O_ACCMODE) == O_WRONLY) { + ret = -EBADF; + goto out; + } + fsdrv = f->fsdev->driver; if (f->size != FILE_SIZE_STREAM && f->pos + count > f->size) @@ -747,7 +752,7 @@ static ssize_t __read(FILE *f, void *buf, size_t count) return 0; ret = fsdrv->read(&f->fsdev->dev, f, buf, count); - +out: if (ret < 0) errno = -ret; return ret; @@ -796,6 +801,11 @@ static ssize_t __write(FILE *f, const void *buf, size_t count) struct fs_driver_d *fsdrv; int ret; + if (!(f->flags & O_ACCMODE)) { + ret = -EBADF; + goto out; + } + fsdrv = f->fsdev->driver; if (f->size != FILE_SIZE_STREAM && f->pos + count > f->size) { ret = fsdrv->truncate(&f->fsdev->dev, f, f->pos + count); -- cgit v1.2.3