From e23947bd76f00701f9407af23e671f4da96f5f25 Mon Sep 17 00:00:00 2001 From: Dmitry Monakhov Date: Thu, 29 Jun 2017 11:31:11 -0700 Subject: bio-integrity: fold bio_integrity_enabled to bio_integrity_prep Currently all integrity prep hooks are open-coded, and if prepare fails we ignore it's code and fail bio with EIO. Let's return real error to upper layer, so later caller may react accordingly. In fact no one want to use bio_integrity_prep() w/o bio_integrity_enabled, so it is reasonable to fold it in to one function. Signed-off-by: Dmitry Monakhov Reviewed-by: Martin K. Petersen [hch: merged with the latest block tree, return bool from bio_integrity_prep] Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/nvdimm/blk.c | 13 ++----------- drivers/nvdimm/btt.c | 13 ++----------- 2 files changed, 4 insertions(+), 22 deletions(-) (limited to 'drivers/nvdimm') diff --git a/drivers/nvdimm/blk.c b/drivers/nvdimm/blk.c index f12d23c49771..1a578b2a437b 100644 --- a/drivers/nvdimm/blk.c +++ b/drivers/nvdimm/blk.c @@ -179,16 +179,8 @@ static blk_qc_t nd_blk_make_request(struct request_queue *q, struct bio *bio) int err = 0, rw; bool do_acct; - /* - * bio_integrity_enabled also checks if the bio already has an - * integrity payload attached. If it does, we *don't* do a - * bio_integrity_prep here - the payload has been generated by - * another kernel subsystem, and we just pass it through. - */ - if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { - bio->bi_status = BLK_STS_IOERR; - goto out; - } + if (!bio_integrity_prep(bio)) + return BLK_QC_T_NONE; bip = bio_integrity(bio); nsblk = q->queuedata; @@ -212,7 +204,6 @@ static blk_qc_t nd_blk_make_request(struct request_queue *q, struct bio *bio) if (do_acct) nd_iostat_end(bio, start); - out: bio_endio(bio); return BLK_QC_T_NONE; } diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c index b6ba0618ea46..b5caaee78bbf 100644 --- a/drivers/nvdimm/btt.c +++ b/drivers/nvdimm/btt.c @@ -1203,16 +1203,8 @@ static blk_qc_t btt_make_request(struct request_queue *q, struct bio *bio) int err = 0; bool do_acct; - /* - * bio_integrity_enabled also checks if the bio already has an - * integrity payload attached. If it does, we *don't* do a - * bio_integrity_prep here - the payload has been generated by - * another kernel subsystem, and we just pass it through. - */ - if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { - bio->bi_status = BLK_STS_IOERR; - goto out; - } + if (!bio_integrity_prep(bio)) + return BLK_QC_T_NONE; do_acct = nd_iostat_start(bio, &start); bio_for_each_segment(bvec, bio, iter) { @@ -1239,7 +1231,6 @@ static blk_qc_t btt_make_request(struct request_queue *q, struct bio *bio) if (do_acct) nd_iostat_end(bio, start); -out: bio_endio(bio); return BLK_QC_T_NONE; } -- cgit v1.2.3 From b1fb2c52b2d85f51f36f1661409f9aeef94265ff Mon Sep 17 00:00:00 2001 From: Dmitry Monakhov Date: Thu, 29 Jun 2017 11:31:13 -0700 Subject: block: guard bvec iteration logic Currently if some one try to advance bvec beyond it's size we simply dump WARN_ONCE and continue to iterate beyond bvec array boundaries. This simply means that we endup dereferencing/corrupting random memory region. Sane reaction would be to propagate error back to calling context But bvec_iter_advance's calling context is not always good for error handling. For safity reason let truncate iterator size to zero which will break external iteration loop which prevent us from unpredictable memory range corruption. And even it caller ignores an error, it will corrupt it's own bvecs, not others. This patch does: - Return error back to caller with hope that it will react on this - Truncate iterator size Code was added long time ago here 4550dd6c, luckily no one hit it in real life :) Signed-off-by: Dmitry Monakhov Reviewed-by: Ming Lei Reviewed-by: Martin K. Petersen [hch: switch to true/false returns instead of errno values] Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/nvdimm/blk.c | 3 ++- drivers/nvdimm/btt.c | 3 ++- include/linux/bio.h | 4 +++- include/linux/bvec.h | 14 +++++++++----- 4 files changed, 16 insertions(+), 8 deletions(-) (limited to 'drivers/nvdimm') diff --git a/drivers/nvdimm/blk.c b/drivers/nvdimm/blk.c index 1a578b2a437b..345acca576b3 100644 --- a/drivers/nvdimm/blk.c +++ b/drivers/nvdimm/blk.c @@ -106,7 +106,8 @@ static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk, len -= cur_len; dev_offset += cur_len; - bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len); + if (!bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len)) + return -EIO; } return err; diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c index b5caaee78bbf..d00c10f382f0 100644 --- a/drivers/nvdimm/btt.c +++ b/drivers/nvdimm/btt.c @@ -985,7 +985,8 @@ static int btt_rw_integrity(struct btt *btt, struct bio_integrity_payload *bip, len -= cur_len; meta_nsoff += cur_len; - bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len); + if (!bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len)) + return -EIO; } return ret; diff --git a/include/linux/bio.h b/include/linux/bio.h index b3b5f5a89a9c..d5e8689f86b8 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -167,8 +167,10 @@ static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, if (bio_no_advance_iter(bio)) iter->bi_size -= bytes; - else + else { bvec_iter_advance(bio->bi_io_vec, iter, bytes); + /* TODO: It is reasonable to complete bio with error here. */ + } } #define __bio_for_each_segment(bvl, bio, iter, start) \ diff --git a/include/linux/bvec.h b/include/linux/bvec.h index 89b65b82d98f..de317b4c13c1 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -22,6 +22,7 @@ #include #include +#include /* * was unsigned short, but we might as well be ready for > 64kB I/O pages @@ -66,12 +67,14 @@ struct bvec_iter { .bv_offset = bvec_iter_offset((bvec), (iter)), \ }) -static inline void bvec_iter_advance(const struct bio_vec *bv, - struct bvec_iter *iter, - unsigned bytes) +static inline bool bvec_iter_advance(const struct bio_vec *bv, + struct bvec_iter *iter, unsigned bytes) { - WARN_ONCE(bytes > iter->bi_size, - "Attempted to advance past end of bvec iter\n"); + if (WARN_ONCE(bytes > iter->bi_size, + "Attempted to advance past end of bvec iter\n")) { + iter->bi_size = 0; + return false; + } while (bytes) { unsigned iter_len = bvec_iter_len(bv, *iter); @@ -86,6 +89,7 @@ static inline void bvec_iter_advance(const struct bio_vec *bv, iter->bi_idx++; } } + return true; } #define for_each_bvec(bvl, bio_vec, iter, start) \ -- cgit v1.2.3