From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin K. Petersen" Subject: [PATCH 1/2] block: Fix for_each_bvec() Date: Tue, 8 Apr 2014 22:43:43 -0400 Message-ID: <1397011424-10970-1-git-send-email-martin.petersen@oracle.com> Return-path: Sender: stable-owner@vger.kernel.org To: axboe@kernel.dk Cc: linux-scsi@vger.kernel.org, "Martin K. Petersen" , Kent Overstreet , Nicholas Bellinger , stable@vger.kernel.org List-Id: linux-scsi@vger.kernel.org From: "Martin K. Petersen" Commit 4550dd6c6b062 introduced for_each_bvec() which iterates over each bvec attached to a bio or bip. However, the macro fails to check bi_size before dereferencing which can lead to crashes while counting/mapping integrity scatterlist segments. Signed-off-by: Martin K. Petersen Cc: Kent Overstreet Cc: Nicholas Bellinger Cc: # v3.14+ --- include/linux/bio.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/bio.h b/include/linux/bio.h index 5a4d39b4686b..5aa372a7380c 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -216,9 +216,9 @@ static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter, } #define for_each_bvec(bvl, bio_vec, iter, start) \ - for ((iter) = start; \ - (bvl) = bvec_iter_bvec((bio_vec), (iter)), \ - (iter).bi_size; \ + for (iter = (start); \ + (iter).bi_size && \ + ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \ bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len)) -- 1.8.3.1