From 9dcafe16d4e83ce1ed740c8cff64a34a899bd8c3 Mon Sep 17 00:00:00 2001 From: Maxim Sobolev Date: Tue, 4 Dec 2018 21:48:56 +0000 Subject: [PATCH] Another attempt to fix issue with the DIOCGDELETE ioctl(2) not handling slightly out-of-bound requests properly (r340187). Perform range check here rather then rely on g_delete_data() to DTRT. The g_delete_data() would always return success for requests starting just the next byte after providers media boundary. MFC after: 4 weeks --- sys/geom/geom_dev.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/sys/geom/geom_dev.c b/sys/geom/geom_dev.c index 2a5aca6b423..e470a516ca7 100644 --- a/sys/geom/geom_dev.c +++ b/sys/geom/geom_dev.c @@ -583,6 +583,20 @@ g_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread error = EINVAL; break; } + if ((cp->provider->mediasize > 0) && + (offset >= cp->provider->mediasize)) { + /* + * Catch out-of-bounds requests here. The problem is + * that due to historical GEOM I/O implementation + * peculatities, g_delete_data() would always return + * success for requests starting just the next byte + * after providers media boundary. Condition check on + * non-zero media size, since that condition would + * (most likely) cause ENXIO instead. + */ + error = EIO; + break; + } while (length > 0) { chunk = length; if (g_dev_del_max_sectors != 0 && chunk >