kernel/linux.git/drivers/block/zram, branch v6.1.168

zram: fix potential UAF of zram table

2025-01-23T16:17:13+00:00

commit 212fe1c0df4a150fb6298db2cfff267ceaba5402 upstream. If zram_meta_alloc failed early, it frees allocated zram->table without setting it NULL. Which will potentially cause zram_meta_free to access the table if user reset an failed and uninitialized device. Link: https://lkml.kernel.org/r/20250107065446.86928-1-ryncsn@gmail.com Fixes: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device") Signed-off-by: Kairui Song Reviewed-by: Sergey Senozhatsky Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

zram: check comp is non-NULL before calling comp_destroy

2025-01-09T12:30:07+00:00

This is a pre-requisite for the backport of commit 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device"), which has been implemented differently in commit 7ac07a26dea7 ("zram: preparation for multi-zcomp support") upstream. We only need to ensure that zcomp_destroy is not called with a NULL comp, so add this check as the other commit cannot be backported easily. Stable-dep-of: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device") Link: https://lore.kernel.org/Z3ytcILx4S1v_ueJ@codewreck.org Suggested-by: Kairui Song Signed-off-by: Dominique Martinet Signed-off-by: Greg Kroah-Hartman

zram: fix uninitialized ZRAM not releasing backing device

2024-12-27T12:52:59+00:00

commit 74363ec674cb172d8856de25776c8f3103f05e2f upstream. Setting backing device is done before ZRAM initialization. If we set the backing device, then remove the ZRAM module without initializing the device, the backing device reference will be leaked and the device will be hold forever. Fix this by always reset the ZRAM fully on rmmod or reset store. Link: https://lkml.kernel.org/r/20241209165717.94215-3-ryncsn@gmail.com Fixes: 013bf95a83ec ("zram: add interface to specif backing device") Signed-off-by: Kairui Song Reported-by: Desheng Wu Suggested-by: Sergey Senozhatsky Reviewed-by: Sergey Senozhatsky Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

zram: refuse to use zero sized block device as backing device

2024-12-27T12:52:58+00:00

commit be48c412f6ebf38849213c19547bc6d5b692b5e5 upstream. Patch series "zram: fix backing device setup issue", v2. This series fixes two bugs of backing device setting: - ZRAM should reject using a zero sized (or the uninitialized ZRAM device itself) as the backing device. - Fix backing device leaking when removing a uninitialized ZRAM device. This patch (of 2): Setting a zero sized block device as backing device is pointless, and one can easily create a recursive loop by setting the uninitialized ZRAM device itself as its own backing device by (zram0 is uninitialized): echo /dev/zram0 > /sys/block/zram0/backing_dev It's definitely a wrong config, and the module will pin itself, kernel should refuse doing so in the first place. By refusing to use zero sized device we avoided misuse cases including this one above. Link: https://lkml.kernel.org/r/20241209165717.94215-1-ryncsn@gmail.com Link: https://lkml.kernel.org/r/20241209165717.94215-2-ryncsn@gmail.com Fixes: 013bf95a83ec ("zram: add interface to specif backing device") Signed-off-by: Kairui Song Reported-by: Desheng Wu Reviewed-by: Sergey Senozhatsky Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

Merge tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-10-14T19:28:43+00:00

Pull more MM updates from Andrew Morton: - fix a race which causes page refcounting errors in ZONE_DEVICE pages (Alistair Popple) - fix userfaultfd test harness instability (Peter Xu) - various other patches in MM, mainly fixes * tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (29 commits) highmem: fix kmap_to_page() for kmap_local_page() addresses mm/page_alloc: fix incorrect PGFREE and PGALLOC for high-order page mm/selftest: uffd: explain the write missing fault check mm/hugetlb: use hugetlb_pte_stable in migration race check mm/hugetlb: fix race condition of uffd missing/minor handling zram: always expose rw_page LoongArch: update local TLB if PTE entry exists mm: use update_mmu_tlb() on the second thread kasan: fix array-bounds warnings in tests hmm-tests: add test for migrate_device_range() nouveau/dmem: evict device private memory during release nouveau/dmem: refactor nouveau_dmem_fault_copy_one() mm/migrate_device.c: add migrate_device_range() mm/migrate_device.c: refactor migrate_vma and migrate_deivce_coherent_page() mm/memremap.c: take a pgmap reference on page allocation mm: free device private pages have zero refcount mm/memory.c: fix race when faulting a device private page mm/damon: use damon_sz_region() in appropriate place mm/damon: move sz_damon_region to damon_sz_region lib/test_meminit: add checks for the allocation functions ...

zram: always expose rw_page

2022-10-13T01:51:50+00:00

Currently zram will adjust its fops to a version which does not contain rw_page when a backing device has been assigned. This is done to prevent upper layers from assuming a synchronous operation when a page may have been written back. This forces every operation through bio which has overhead associated with bio_alloc/frees. The code can be simplified to always expose an rw_page method and only in the rare event that a page is written back we instead will return -EOPNOTSUPP forcing the upper layer to fallback to bio. Link: https://lkml.kernel.org/r/20221003144832.2906610-1-bgeffon@google.com Signed-off-by: Brian Geffon Reviewed-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nitin Gupta Cc: Rom Lemarchand Cc: Suleiman Souhlal Signed-off-by: Andrew Morton

Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-10-11T00:53:04+00:00

Pull MM updates from Andrew Morton: - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam Howlett. An overlapping range-based tree for vmas. It it apparently slightly more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat at [1]. This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1] * tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits) hugetlb: allocate vma lock for all sharable vmas hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer hugetlb: fix vma lock handling during split vma and range unmapping mglru: mm/vmscan.c: fix imprecise comments mm/mglru: don't sync disk for each aging cycle mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol mm: memcontrol: use do_memsw_account() in a few more places mm: memcontrol: deprecate swapaccounting=0 mode mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled mm/secretmem: remove reduntant return value mm/hugetlb: add available_huge_pages() func mm: remove unused inline functions from include/linux/mm_inline.h selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd selftests/vm: add thp collapse shmem testing selftests/vm: add thp collapse file and tmpfs testing selftests/vm: modularize thp collapse memory operations selftests/vm: dedup THP helpers mm/khugepaged: add tracepoint to hpage_collapse_scan_file() mm/madvise: add file and shmem support to MADV_COLLAPSE ...

Merge tag 'for-6.1/block-2022-10-03' of git://git.kernel.dk/linux

2022-10-07T16:19:14+00:00

Pull block updates from Jens Axboe: - NVMe pull requests via Christoph: - handle number of queue changes in the TCP and RDMA drivers (Daniel Wagner) - allow changing the number of queues in nvmet (Daniel Wagner) - also consider host_iface when checking ip options (Daniel Wagner) - don't map pages which can't come from HIGHMEM (Fabio M. De Francesco) - avoid unnecessary flush bios in nvmet (Guixin Liu) - shrink and better pack the nvme_iod structure (Keith Busch) - add comment for unaligned "fake" nqn (Linjun Bao) - print actual source IP address through sysfs "address" attr (Martin Belanger) - various cleanups (Jackie Liu, Wolfram Sang, Genjian Zhang) - handle effects after freeing the request (Keith Busch) - copy firmware_rev on each init (Keith Busch) - restrict management ioctls to admin (Keith Busch) - ensure subsystem reset is single threaded (Keith Busch) - report the actual number of tagset maps in nvme-pci (Keith Busch) - small fabrics authentication fixups (Christoph Hellwig) - add common code for tagset allocation and freeing (Christoph Hellwig) - stop using the request_queue in nvmet (Christoph Hellwig) - set min_align_mask before calculating max_hw_sectors (Rishabh Bhatnagar) - send a rediscover uevent when a persistent discovery controller reconnects (Sagi Grimberg) - misc nvmet-tcp fixes (Varun Prakash, zhenwei pi) - MD pull request via Song: - Various raid5 fix and clean up, by Logan Gunthorpe and David Sloan. - Raid10 performance optimization, by Yu Kuai. - sbitmap wakeup hang fixes (Hugh, Keith, Jan, Yu) - IO scheduler switching quisce fix (Keith) - s390/dasd block driver updates (Stefan) - support for recovery for the ublk driver (ZiyangZhang) - rnbd drivers fixes and updates (Guoqing, Santosh, ye, Christoph) - blk-mq and null_blk map fixes (Bart) - various bcache fixes (Coly, Jilin, Jules) - nbd signal hang fix (Shigeru) - block writeback throttling fix (Yu) - optimize the passthrough mapping handling (me) - prepare block cgroups to being gendisk based (Christoph) - get rid of an old PSI hack in the block layer, moving it to the callers instead where it belongs (Christoph) - blk-throttle fixes and cleanups (Yu) - misc fixes and cleanups (Liu Shixin, Liu Song, Miaohe, Pankaj, Ping-Xiang, Wolfram, Saurabh, Li Jinlin, Li Lei, Lin, Li zeming, Miaohe, Bart, Coly, Gaosheng * tag 'for-6.1/block-2022-10-03' of git://git.kernel.dk/linux: (162 commits) sbitmap: fix lockup while swapping block: add rationale for not using blk_mq_plug() when applicable block: adapt blk_mq_plug() to not plug for writes that require a zone lock s390/dasd: use blk_mq_alloc_disk blk-cgroup: don't update the blkg lookup hint in blkg_conf_prep nvmet: don't look at the request_queue in nvmet_bdev_set_limits nvmet: don't look at the request_queue in nvmet_bdev_zone_mgmt_emulate_all blk-mq: use quiesced elevator switch when reinitializing queues block: replace blk_queue_nowait with bdev_nowait nvme: remove nvme_ctrl_init_connect_q nvme-loop: use the tagset alloc/free helpers nvme-loop: store the generic nvme_ctrl in set->driver_data nvme-loop: initialize sqsize later nvme-fc: use the tagset alloc/free helpers nvme-fc: store the generic nvme_ctrl in set->driver_data nvme-fc: keep ctrl->sqsize in sync with opts->queue_size nvme-rdma: use the tagset alloc/free helpers nvme-rdma: store the generic nvme_ctrl in set->driver_data nvme-tcp: use the tagset alloc/free helpers nvme-tcp: store the generic nvme_ctrl in set->driver_data ...

zram: keep comments within 80-columns limit

2022-10-03T21:03:09+00:00

Several trivial fixups (that I should have spotted during review). Link: https://lkml.kernel.org/r/20220914052033.838050-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky Signed-off-by: Andrew Morton

zram: do not waste zram_table_entry flags bits

2022-10-03T21:03:09+00:00

zram_table_entry::flags stores object size in the lower bits and zram pageflags in the upper bits. However, for some reason, we use 24 lower bits, while maximum zram object size is PAGE_SIZE, which requires PAGE_SHIFT bits (up to 16 on arm64). This wastes 24 - PAGE_SHIFT bits that we can use for additional zram pageflags instead. Also add a BUILD_BUG_ON() to alert us should we run out of bits in zram_table_entry::flags. Link: https://lkml.kernel.org/r/20220912152744.527438-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky Reviewed-by: Brian Geffon Acked-by: Minchan Kim Cc: Nitin Gupta Signed-off-by: Andrew Morton