If the fd is invalid or interrupted by signal.
-----邮件原件-----
发件人: Paolo Bonzini [mailto:pbonz...@redhat.com]
发送时间: 2019年3月21日 18:38
收件人: lizhengui; stefa...@redhat.com; mre...@redhat.com; kw...@redhat.com
抄送: qemu-bl...@nongnu.org; qemu-devel@nongnu.org; Fangyi (C); wangjie (P)
主题: Re: [PATCH] qemu-pr-helper: check the return value of fcntl in do_pr_out
On 20/03/19 15:07, Zhengui li wrote:
> The function fcntl maybe return -1, which is not a unsigned type.
> Unsigned type or Negative values should not do bitwise operator with
> O_ACCMODE.
Did you actually find a case in which the fcntl can fail?
Paolo
> Signed-off-by: Zhengui li <lizhen...@huawei.com>
> ---
> scsi/qemu-pr-helper.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/scsi/qemu-pr-helper.c b/scsi/qemu-pr-helper.c index
> e7af637..fcbe4d9 100644
> --- a/scsi/qemu-pr-helper.c
> +++ b/scsi/qemu-pr-helper.c
> @@ -551,8 +551,14 @@ static int do_pr_out(int fd, const uint8_t *cdb, uint8_t
> *sense,
> const uint8_t *param, int sz) {
> int resp_sz;
> + int flags;
>
> - if ((fcntl(fd, F_GETFL) & O_ACCMODE) == O_RDONLY) {
> + flags = fcntl(fd, F_GETFL);
> + if (flags < 0) {
> + return -1;
> + }
> +
> + if (((unsigned int) flags & O_ACCMODE) == O_RDONLY) {
> scsi_build_sense(sense, SENSE_CODE(INVALID_OPCODE));
> return CHECK_CONDITION;
> }
>
