From 758c5b5c02d0a50f00032a2cda533f5590fb47a7 Mon Sep 17 00:00:00 2001 From: Mark Johnston Date: Thu, 28 Dec 2023 12:08:04 -0500 Subject: cam: Let cam_periph_unmapmem() return an error As of commit b059686a71c8, cam_periph_unmapmem() can legitimately fail if the copyout() operation fails. However, this failure was never signaled to upper layers. In practice it is unlikely to occur since cap_periph_mapmem() would most likely fail in such circumstances anyway, but an error is nonetheless possible. However, some code reading revealed a few paths where the return value of cam_periph_mapmem() is not checked, and this is definitely a bug. Add error checking there and let cam_periph_unmapmem() return errors from copyout(). Reviewed by: dab, mav MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D43201 (cherry picked from commit d068ea16e3264c2d62472a8acf794262cfe703dd) --- sys/cam/cam_compat.c | 21 +++++++++++++-------- sys/cam/cam_periph.c | 21 +++++++++++++-------- sys/cam/cam_periph.h | 2 +- sys/cam/cam_xpt.c | 4 +--- sys/cam/nvme/nvme_da.c | 5 +++-- sys/cam/scsi/scsi_pass.c | 4 ++-- sys/cam/scsi/scsi_sg.c | 6 ++++-- sys/cam/scsi/scsi_target.c | 29 ++++++++++++++++++++--------- 8 files changed, 57 insertions(+), 35 deletions(-) diff --git a/sys/cam/cam_compat.c b/sys/cam/cam_compat.c index c377763fc7c5..aed3916267d5 100644 --- a/sys/cam/cam_compat.c +++ b/sys/cam/cam_compat.c @@ -380,11 +380,13 @@ cam_compat_translate_dev_match_0x18(union ccb *ccb) struct dev_match_result *dm; struct dev_match_result_0x18 *dm18; struct cam_periph_map_info mapinfo; - int i; + int error, i; /* Remap the CCB into kernel address space */ bzero(&mapinfo, sizeof(mapinfo)); - cam_periph_mapmem(ccb, &mapinfo, maxphys); + error = cam_periph_mapmem(ccb, &mapinfo, maxphys); + if (error != 0) + return (error); dm = ccb->cdm.matches; /* Translate in-place: old fields are smaller */ @@ -432,21 +434,22 @@ cam_compat_translate_dev_match_0x18(union ccb *ccb) } } - cam_periph_unmapmem(ccb, &mapinfo); - - return (0); + return (cam_periph_unmapmem(ccb, &mapinfo)); } static int cam_compat_handle_0x19(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td, d_ioctl_t *cbfnp) { + struct cam_periph_map_info mapinfo; union ccb *ccb = (union ccb *)addr; - struct cam_periph_map_info mapinfo; + int error; if (cmd == CAMIOCOMMAND && ccb->ccb_h.func_code == XPT_DEV_MATCH) { bzero(&mapinfo, sizeof(mapinfo)); - cam_periph_mapmem(ccb, &mapinfo, maxphys); + error = cam_periph_mapmem(ccb, &mapinfo, maxphys); + if (error != 0) + return (error); for (int i = 0; i < ccb->cdm.num_patterns; i++) { struct dev_match_pattern *p = &ccb->cdm.patterns[i]; @@ -460,7 +463,9 @@ cam_compat_handle_0x19(struct cdev *dev, u_long cmd, caddr_t addr, int flag, p->pattern.periph_pattern.flags == 0x01f) p->pattern.periph_pattern.flags = PERIPH_MATCH_ANY; } - cam_periph_unmapmem(ccb, &mapinfo); + error = cam_periph_unmapmem(ccb, &mapinfo); + if (error != 0) + return (error); } return ((cbfnp)(dev, cmd, addr, flag, td)); } diff --git a/sys/cam/cam_periph.c b/sys/cam/cam_periph.c index ebdda9ef449f..af187d3eab51 100644 --- a/sys/cam/cam_periph.c +++ b/sys/cam/cam_periph.c @@ -1014,17 +1014,17 @@ fail: * Unmap memory segments mapped into kernel virtual address space by * cam_periph_mapmem(). */ -void +int cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo) { - int numbufs, i; + int error, numbufs, i; uint8_t **data_ptrs[CAM_PERIPH_MAXMAPS]; uint32_t lengths[CAM_PERIPH_MAXMAPS]; uint32_t dirs[CAM_PERIPH_MAXMAPS]; if (mapinfo->num_bufs_used <= 0) { /* nothing to free and the process wasn't held. */ - return; + return (0); } switch (ccb->ccb_h.func_code) { @@ -1089,12 +1089,11 @@ cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo) numbufs = 1; break; default: - /* allow ourselves to be swapped once again */ - PRELE(curproc); - return; - break; /* NOTREACHED */ + numbufs = 0; + break; } + error = 0; for (i = 0; i < numbufs; i++) { if (mapinfo->bp[i]) { /* unmap the buffer */ @@ -1104,8 +1103,12 @@ cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo) uma_zfree(pbuf_zone, mapinfo->bp[i]); } else { if (dirs[i] != CAM_DIR_OUT) { - copyout(*data_ptrs[i], mapinfo->orig[i], + int error1; + + error1 = copyout(*data_ptrs[i], mapinfo->orig[i], lengths[i]); + if (error == 0) + error = error1; } free(*data_ptrs[i], M_CAMPERIPH); } @@ -1116,6 +1119,8 @@ cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo) /* allow ourselves to be swapped once again */ PRELE(curproc); + + return (error); } int diff --git a/sys/cam/cam_periph.h b/sys/cam/cam_periph.h index d0f04388b181..ad18ee6b204c 100644 --- a/sys/cam/cam_periph.h +++ b/sys/cam/cam_periph.h @@ -180,7 +180,7 @@ void cam_periph_invalidate(struct cam_periph *periph); int cam_periph_mapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo, u_int maxmap); -void cam_periph_unmapmem(union ccb *ccb, +int cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo); union ccb *cam_periph_getccb(struct cam_periph *periph, uint32_t priority); diff --git a/sys/cam/cam_xpt.c b/sys/cam/cam_xpt.c index 26e656fc5ff2..6eac81c18160 100644 --- a/sys/cam/cam_xpt.c +++ b/sys/cam/cam_xpt.c @@ -566,11 +566,9 @@ xptdoioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread * /* * Map the buffers back into user space. */ - cam_periph_unmapmem(inccb, &mapinfo); + error = cam_periph_unmapmem(inccb, &mapinfo); inccb->ccb_h.path = old_path; - - error = 0; break; } default: diff --git a/sys/cam/nvme/nvme_da.c b/sys/cam/nvme/nvme_da.c index e8e75a121679..9901ecccf21c 100644 --- a/sys/cam/nvme/nvme_da.c +++ b/sys/cam/nvme/nvme_da.c @@ -438,8 +438,9 @@ ndaioctl(struct disk *dp, u_long cmd, void *data, int fflag, * Tear down mapping and return status. */ cam_periph_unlock(periph); - cam_periph_unmapmem(ccb, &mapinfo); - error = cam_ccb_success(ccb) ? 0 : EIO; + error = cam_periph_unmapmem(ccb, &mapinfo); + if (!cam_ccb_success(ccb)) + error = EIO; out: cam_periph_lock(periph); xpt_release_ccb(ccb); diff --git a/sys/cam/scsi/scsi_pass.c b/sys/cam/scsi/scsi_pass.c index cf27c304d919..ff48bed30e68 100644 --- a/sys/cam/scsi/scsi_pass.c +++ b/sys/cam/scsi/scsi_pass.c @@ -2237,14 +2237,14 @@ passsendccb(struct cam_periph *periph, union ccb *ccb, union ccb *inccb) } cam_periph_unlock(periph); - cam_periph_unmapmem(ccb, &mapinfo); + error = cam_periph_unmapmem(ccb, &mapinfo); cam_periph_lock(periph); ccb->ccb_h.cbfcnp = NULL; ccb->ccb_h.periph_priv = inccb->ccb_h.periph_priv; bcopy(ccb, inccb, sizeof(union ccb)); - return(0); + return (error); } /* diff --git a/sys/cam/scsi/scsi_sg.c b/sys/cam/scsi/scsi_sg.c index b17a156503a2..66ea4b4aa2d7 100644 --- a/sys/cam/scsi/scsi_sg.c +++ b/sys/cam/scsi/scsi_sg.c @@ -883,7 +883,7 @@ sgsendccb(struct cam_periph *periph, union ccb *ccb) { struct sg_softc *softc; struct cam_periph_map_info mapinfo; - int error; + int error, error1; softc = periph->softc; bzero(&mapinfo, sizeof(mapinfo)); @@ -908,7 +908,9 @@ sgsendccb(struct cam_periph *periph, union ccb *ccb) softc->device_stats); cam_periph_unlock(periph); - cam_periph_unmapmem(ccb, &mapinfo); + error1 = cam_periph_unmapmem(ccb, &mapinfo); + if (error == 0) + error = error1; cam_periph_lock(periph); return (error); diff --git a/sys/cam/scsi/scsi_target.c b/sys/cam/scsi/scsi_target.c index 45a5eb8415b9..6b2fd5adb4ee 100644 --- a/sys/cam/scsi/scsi_target.c +++ b/sys/cam/scsi/scsi_target.c @@ -906,18 +906,29 @@ targreturnccb(struct targ_softc *softc, union ccb *ccb) u_ccbh = &descr->user_ccb->ccb_h; /* Copy out the central portion of the ccb_hdr */ - copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count, - offsetof(struct ccb_hdr, periph_priv) - - offsetof(struct ccb_hdr, retry_count)); + error = copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count, + offsetof(struct ccb_hdr, periph_priv) - + offsetof(struct ccb_hdr, retry_count)); + if (error != 0) { + xpt_print(softc->path, + "targreturnccb - CCB header copyout failed (%d)\n", error); + } /* Copy out the rest of the ccb (after the ccb_hdr) */ ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr); - if (descr->mapinfo.num_bufs_used != 0) - cam_periph_unmapmem(ccb, &descr->mapinfo); - error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len); - if (error != 0) { - xpt_print(softc->path, - "targreturnccb - CCB copyout failed (%d)\n", error); + if (descr->mapinfo.num_bufs_used != 0) { + int error1; + + error1 = cam_periph_unmapmem(ccb, &descr->mapinfo); + if (error == 0) + error = error1; + } + if (error == 0) { + error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len); + if (error != 0) { + xpt_print(softc->path, + "targreturnccb - CCB copyout failed (%d)\n", error); + } } /* Free CCB or send back to devq. */ targfreeccb(softc, ccb); -- cgit v1.2.3