Bug 203861
| Summary: | Division by zero error in fsck.f2fs when fixing a corrupted image | ||
|---|---|---|---|
| Product: | File System | Reporter: | Seulbae Kim (seulbae) |
| Component: | f2fs | Assignee: | Default virtual assignee for f2fs (filesystem_f2fs) |
| Status: | RESOLVED CODE_FIX | ||
| Severity: | normal | CC: | chao, seulbae |
| Priority: | P1 | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Kernel Version: | v4.18 | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
| Attachments: | Corrupted f2fs image (compressed) | ||
Sorry for the long delay, I forgot to reply this thread to let you know we have fixed this issue with below patch, could you please check it with your testcase? https://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs-tools.git/commit/?h=dev&id=d5bec9021f50f3d1e05aee3fe76160dc234c1735 No problem. I checked that the bug is fixed through the patch. Thank you! Thanks for confirming that! :) |
Created attachment 283179 [details] Corrupted f2fs image (compressed) [Overview] fsck.f2fs of f2fs-tools (master at commit 54244dcafd) triggers a division by zero error while fixing a corrupted image, in which segs->secs_per_zone is set to 0. [Reproduction] Download and uncompress the attached image. Run fsck.f2fs against the downloaded image: $ cd path/to/f2fs-tools/ $ ./fsck/fsck.f2fs -d 0 -f /tmp/f2fs.img Info: Force to fix corruption Info: Segments per section = 1 Info: Sections per zone = 1 Info: sector size = 512 Info: total sectors = 131072 (64 MB) Info: MKFS version "Linux version 4.13.0-45-generic (buildd@lgw01-amd64-011) (gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.9)) #50~16.04.1-Ubuntu SMP Wed May 30 11:18:27 UTC 2018" Info: FSCK version from "Linux version 4.13.0-45-generic (buildd@lgw01-amd64-011) (gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.9)) #50~16.04.1-Ubuntu SMP Wed May 30 11:18:27 UTC 2018" to "Linux version 4.18.0-21-generic (buildd@lcy01-amd64-006) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #22~18.04.1-Ubuntu SMP Thu May 16 15:07:19 UTC 2019" [update_superblock: 503] Info: Done to update superblock Info: superblock features = 0 : Info: superblock encrypt level = 0, salt = 00000000000000000000000000000000 Info: total FS sectors = 131072 (64 MB) Info: CKPT version = 3 [1] 13488 floating point exception (core dumped) ./fsck/fsck.f2fs -f /tmp/f2fs.img [Location] - build_curseg at fsck/mount.c:1589 1589 array[i].zone = GET_ZONENO_FROM_SEGNO(sbi, segno); - GET_ZONENO_FROM_SEGNO(sbi, segno) at fsck/f2fs.h:317 318 ((segno / sbi->segs_per_sec) / sbi->secs_per_zone) Causes division by zero error when sbi->secs_per_zone is corrupted to be 0.