From: Wu Bo Date: Tue, 14 Apr 2020 10:13:28 +0800 Subject: scsi: sg: add sg_remove_request in sg_write Origin: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit?id=34fcb4291e234468f9bf9d4b851c9f522f3bbb13 Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2020-12770 commit 83c6f2390040f188cc25b270b4befeb5628c1aee upstream. If the __copy_from_user function failed we need to call sg_remove_request in sg_write. Link: https://lore.kernel.org/r/610618d9-e983-fd56-ed0f-639428343af7@huawei.com Acked-by: Douglas Gilbert Signed-off-by: Wu Bo Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin [groeck: Backport to v5.4.y and older kernels] Signed-off-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/sg.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index ac8535d2b41a..6bb45ae19d58 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -694,8 +694,10 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos) hp->flags = input_size; /* structure abuse ... */ hp->pack_id = old_hdr.pack_id; hp->usr_ptr = NULL; - if (__copy_from_user(cmnd, buf, cmd_size)) + if (__copy_from_user(cmnd, buf, cmd_size)) { + sg_remove_request(sfp, srp); return -EFAULT; + } /* * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV, * but is is possible that the app intended SG_DXFER_TO_DEV, because there -- 2.27.0.rc0