On 18/07/2019 13:41, Tom Eccles wrote: > On 17/07/2019 8:49 pm, Milan Broz wrote: >> If you can still reproduce it, please send version of the utility and >> kernel (and --debug output as suggested in another mail) and if you have some >> data/hash/fec images that can be used to reproduce it, let me know where I can find it. > > Attached is a bash script gen_image.sh which should reproduce the issue. > find_and_corrupt.c should be in the working directory when gen_image.sh is > run. find_and_corrupt.c corrupts the disk image by simply searching for a > known string and introducing an error (see the diff outputted by gen_image.sh). > > See in particular the error and dmesg sample when reading the corrupted file > (gen_image.sh:77) and the success when running veritysetup verify > (gen_image.sh:86). > > I have created an issue at https://gitlab.com/cryptsetup/cryptsetup/issues/462 Thanks. I think I see the problem, and it is actually not FEC related. Could you please try to manually allocate loop devices in RW mode (not read-only as we have during automatic loop allocation if mapping image is in file) over the provided images, and then use these loop device as arguments for the veritysetup? Like # losetup /dev/loop0 data8M.img.corrupt # losetup /dev/loop1 hash-img # losetup /dev/loop2 fec-img and # veritysetup open --fec-roots 24 --fec-device /dev/loop2 /dev/loop0 test /dev/loop1 15546e6799bb13608c77fa9cb840682a2dec3cfdb948d942ff3487f537966c01 --debug Does it correct the data now? For me it prints kernel: device-mapper: verity: sha256 using implementation "sha256-generic" kernel: fec_decode_bufs: 13 callbacks suppressed kernel: device-mapper: verity-fec: 7:0: FEC 0: corrected 153 errors Milan _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx https://www.saout.de/mailman/listinfo/dm-crypt
