mirror/freebsd
1
0
Fork 0
mirror of https://git.FreeBSD.org/src.git synced 2025-01-15 15:06:42 +00:00
Code Issues Releases Activity

Fix an obscure fencepost error in GBDE's sector mapping code:

Browse Source 
For certain combinations of sectorsize, mediasize and random numbers
(used to define the mapping), a multisector read or write would ignore
some subset of the sectors past the first sector in the request because
those sectors would be mapped past the end of the parent device, and
normal "end of media" truncation would zap that part of the request.

Rev 1.19+1.20 of g_bde_work.c added the check which should have alerted
me to this happening.  This commit maps the request correctly and
adds KASSERTS to make sure things stay inside the parent device.

This does not change the on-disk layout of GBDE, there is no need to
backup/restore.
This commit is contained in:
Poul-Henning Kamp 2003-04-29 19:46:42 +00:00
parent a17da2aa74
commit c7f3baedf3
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=114251
1 changed files with 26 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
sys/geom/bde/g_bde_crypt.c
View File

@ -331,6 +331,8 @@ g_bde_map_sector(struct g_bde_work *wp)
wp->so = zone * kp->zone_width + zoff;
wp->so += kp->keyoffset;
wp->so %= kp->media_width;
if (wp->so + wp->length > kp->media_width)
wp->length = kp->media_width - wp->so;
wp->so += kp->sector0;
/* The key sector is the last in this zone. */
@ -364,4 +366,28 @@ g_bde_map_sector(struct g_bde_work *wp)
(intmax_t)wp->kso,
wp->ko);
#endif
KASSERT(wp->so + wp->length <= kp->sectorN,
("wp->so (%qd) + wp->length (%qd) > EOM (%qd), offset = %qd",
(intmax_t)wp->so,
(intmax_t)wp->length,
(intmax_t)kp->sectorN,
(intmax_t)wp->offset));
KASSERT(wp->kso + kp->sectorsize <= kp->sectorN,
("wp->kso (%qd) + kp->sectorsize > EOM (%qd), offset = %qd",
(intmax_t)wp->kso,
(intmax_t)kp->sectorN,
(intmax_t)wp->offset));
KASSERT(wp->so >= kp->sector0,
("wp->so (%qd) < BOM (%qd), offset = %qd",
(intmax_t)wp->so,
(intmax_t)kp->sector0,
(intmax_t)wp->offset));
KASSERT(wp->kso >= kp->sector0,
("wp->kso (%qd) <BOM (%qd), offset = %qd",
(intmax_t)wp->kso,
(intmax_t)kp->sector0,
(intmax_t)wp->offset));
}