Description
In the Linux kernel, the following vulnerability has been resolved: blk-iocost: fix divide by 0 error in calc_lcoefs() echo max of u64 to cost.model can cause divide by 0 error. # echo 8:0 rbps=18446744073709551615 > /sys/fs/cgroup/io.cost.model divide error: 0000 [#1] PREEMPT SMP RIP: 0010:calc_lcoefs+0x4c/0xc0 Call Trace: <TASK> ioc_refresh_params+0x2b3/0x4f0 ioc_cost_model_write+0x3cb/0x4c0 ? _copy_from_iter+0x6d/0x6c0 ? kernfs_fop_write_iter+0xfc/0x270 cgroup_file_write+0xa0/0x200 kernfs_fop_write_iter+0x17d/0x270 vfs_write+0x414/0x620 ksys_write+0x73/0x160 __x64_sys_write+0x1e/0x30 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd calc_lcoefs() uses the input value of cost.model in DIV_ROUND_UP_ULL, overflow would happen if bps plus IOC_PAGE_SIZE is greater than ULLONG_MAX, it can cause divide by 0 error. Fix the problem by setting basecost
Product status
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 9e8bf9f95f7a299fa9ea45b678d001806ad5e12c
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 6e291810fe83a384700eb24a1f714966391ed562
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 3538ade9d8c2ba41088e395de916f2599fadba8f
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before bf8eb1fd6110871e6232e8e7efe399276ef7e6f6
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before b96d7b4a9745fbd0c8384608ceb1f50415e862fa
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (git) before 984af1e66b4126cf145153661cc24c213e2ec231
5.4.235 (semver)
5.10.173 (semver)
5.15.99 (semver)
6.1.16 (semver)
6.2.3 (semver)
6.3 (original_commit_for_fix)
References
git.kernel.org/...c/9e8bf9f95f7a299fa9ea45b678d001806ad5e12c
git.kernel.org/...c/6e291810fe83a384700eb24a1f714966391ed562
git.kernel.org/...c/3538ade9d8c2ba41088e395de916f2599fadba8f
git.kernel.org/...c/bf8eb1fd6110871e6232e8e7efe399276ef7e6f6
git.kernel.org/...c/b96d7b4a9745fbd0c8384608ceb1f50415e862fa
git.kernel.org/...c/984af1e66b4126cf145153661cc24c213e2ec231
