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2024-07-03mm: memory: convert clear_huge_page() to folio_zero_user()Kefeng Wang1-1/+1
Patch series "mm: improve clear and copy user folio", v2. Some folio conversions. An improvement is to move address alignment into the caller as it is only needed if we don't know which address will be accessed when clearing/copying user folios. This patch (of 4): Replace clear_huge_page() with folio_zero_user(), and take a folio instead of a page. Directly get number of pages by folio_nr_pages() to remove pages_per_huge_page argument, furthermore, move the address alignment from folio_zero_user() to the callers since the alignment is only needed when we don't know which address will be accessed. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kefeng Wang <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: "Huang, Ying" <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: Muchun Song <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03fs/proc/task_mmu: use folio API in pte_is_pinned()Kefeng Wang1-4/+4
Patch series "mm: remove page_maybe_dma_pinned() and page_mkclean()". Most page_maybe_dma_pinned() and page_mkclean() callers have been converted to the folio equivalents, after two more convertsions, remove them and update the comment and documention. This patch (of 4): Convert to use vm_normal_folio() and folio_maybe_dma_pinned() API, which helps to remove page_maybe_dma_pinned() in the subsequent change. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kefeng Wang <[email protected]> Acked-by: David Hildenbrand <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: Helge Deller <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03nilfs2: fix incorrect inode allocation from reserved inodesRyusuke Konishi4-12/+20
If the bitmap block that manages the inode allocation status is corrupted, nilfs_ifile_create_inode() may allocate a new inode from the reserved inode area where it should not be allocated. Previous fix commit d325dc6eb763 ("nilfs2: fix use-after-free bug of struct nilfs_root"), fixed the problem that reserved inodes with inode numbers less than NILFS_USER_INO (=11) were incorrectly reallocated due to bitmap corruption, but since the start number of non-reserved inodes is read from the super block and may change, in which case inode allocation may occur from the extended reserved inode area. If that happens, access to that inode will cause an IO error, causing the file system to degrade to an error state. Fix this potential issue by adding a wraparound option to the common metadata object allocation routine and by modifying nilfs_ifile_create_inode() to disable the option so that it only allocates inodes with inode numbers greater than or equal to the inode number read in "nilfs->ns_first_ino", regardless of the bitmap status of reserved inodes. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Ryusuke Konishi <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Jan Kara <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03nilfs2: add missing check for inode numbers on directory entriesRyusuke Konishi2-0/+11
Syzbot reported that mounting and unmounting a specific pattern of corrupted nilfs2 filesystem images causes a use-after-free of metadata file inodes, which triggers a kernel bug in lru_add_fn(). As Jan Kara pointed out, this is because the link count of a metadata file gets corrupted to 0, and nilfs_evict_inode(), which is called from iput(), tries to delete that inode (ifile inode in this case). The inconsistency occurs because directories containing the inode numbers of these metadata files that should not be visible in the namespace are read without checking. Fix this issue by treating the inode numbers of these internal files as errors in the sanity check helper when reading directory folios/pages. Also thanks to Hillf Danton and Matthew Wilcox for their initial mm-layer analysis. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Ryusuke Konishi <[email protected]> Reported-by: [email protected] Closes: https://syzkaller.appspot.com/bug?extid=d79afb004be235636ee8 Reported-by: Jan Kara <[email protected]> Closes: https://lkml.kernel.org/r/20240617075758.wewhukbrjod5fp5o@quack3 Tested-by: Ryusuke Konishi <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03nilfs2: fix inode number range checksRyusuke Konishi3-3/+10
Patch series "nilfs2: fix potential issues related to reserved inodes". This series fixes one use-after-free issue reported by syzbot, caused by nilfs2's internal inode being exposed in the namespace on a corrupted filesystem, and a couple of flaws that cause problems if the starting number of non-reserved inodes written in the on-disk super block is intentionally (or corruptly) changed from its default value. This patch (of 3): In the current implementation of nilfs2, "nilfs->ns_first_ino", which gives the first non-reserved inode number, is read from the superblock, but its lower limit is not checked. As a result, if a number that overlaps with the inode number range of reserved inodes such as the root directory or metadata files is set in the super block parameter, the inode number test macros (NILFS_MDT_INODE and NILFS_VALID_INODE) will not function properly. In addition, these test macros use left bit-shift calculations using with the inode number as the shift count via the BIT macro, but the result of a shift calculation that exceeds the bit width of an integer is undefined in the C specification, so if "ns_first_ino" is set to a large value other than the default value NILFS_USER_INO (=11), the macros may potentially malfunction depending on the environment. Fix these issues by checking the lower bound of "nilfs->ns_first_ino" and by preventing bit shifts equal to or greater than the NILFS_USER_INO constant in the inode number test macros. Also, change the type of "ns_first_ino" from signed integer to unsigned integer to avoid the need for type casting in comparisons such as the lower bound check introduced this time. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Ryusuke Konishi <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Jan Kara <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03fs/proc: move page_mapcount() to fs/proc/internal.hDavid Hildenbrand3-24/+65
... and rename it to folio_precise_page_mapcount(). fs/proc is the last remaining user, and that should stay that way. While at it, cleanup kpagecount_read() a bit: there are still some legacy leftovers -- when the interface was introduced it returned the page refcount, but was changed briefly afterwards to return the page mapcount. Further, some simple folio conversion. Once we stop using the per-page mapcounts of large folios, all folio_precise_page_mapcount() users will have to implement an alternative way to achieve what they are trying to achieve, possibly in a less precise way. [[email protected]: fix uninitialized variable in pagemap_pmd_range()] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Signed-off-by: Dan Carpenter <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Lance Yang <[email protected]> Cc: Oscar Salvador <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03fs/proc/task_mmu: account non-present entries as "maybe shared, but no idea ↵David Hildenbrand1-22/+31
how often" We currently rely on mapcount information for pages referenced by non-present entries to calculate the USS (shared vs. private) and the PSS. However, relying on mapcounts for non-present entries doesn't make any sense. We have to treat such entries as "maybe shared, but no idea how often", implying that they will *not* get accounted towards the USS, and will get fully accounted to the PSS (no idea how often shared). There is one exception: device exclusive entries essentially behave like present entries (e.g., mapcount incremented). In smaps_pmd_entry(), use is_pfn_swap_entry() instead of is_migration_entry(), which should not make a real difference but makes the code look more similar to the PTE variant. While at it, adjust the comments in smaps_account(). Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Lance Yang <[email protected]> Cc: Oscar Salvador <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03fs/proc/task_mmu: properly detect PM_MMAP_EXCLUSIVE per page of PMD-mapped THPsDavid Hildenbrand1-10/+12
We added PM_MMAP_EXCLUSIVE in 2015 via commit 77bb499bb60f ("pagemap: add mmap-exclusive bit for marking pages mapped only here"), when THPs could not be partially mapped and page_mapcount() returned something that was true for all pages of the THP. In 2016, we added support for partially mapping THPs via commit 53f9263baba6 ("mm: rework mapcount accounting to enable 4k mapping of THPs") but missed to determine PM_MMAP_EXCLUSIVE as well per page. Checking page_mapcount() on the head page does not tell the whole story. We should check each individual page. In a future without per-page mapcounts it will be different, but we'll change that to be consistent with PTE-mapped THPs once we deal with that. Link: https://lkml.kernel.org/r/[email protected] Fixes: 53f9263baba6 ("mm: rework mapcount accounting to enable 4k mapping of THPs") Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Lance Yang <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03fs/proc/task_mmu: don't indicate PM_MMAP_EXCLUSIVE without PM_PRESENTDavid Hildenbrand1-6/+2
Relying on the mapcount for non-present PTEs that reference pages doesn't make any sense: they are not accounted in the mapcount, so page_mapcount() == 1 won't return the result we actually want to know. While we don't check the mapcount for migration entries already, we could end up checking it for swap, hwpoison, device exclusive, ... entries, which we really shouldn't. There is one exception: device private entries, which we consider fake-present (e.g., incremented the mapcount). But we won't care about that for now for PM_MMAP_EXCLUSIVE, because indicating PM_SWAP for them although they are fake-present already sounds suspiciously wrong. Let's never indicate PM_MMAP_EXCLUSIVE without PM_PRESENT. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Lance Yang <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03fs/proc/task_mmu: indicate PM_FILE for PMD-mapped file THPDavid Hildenbrand1-0/+2
Patch series "fs/proc: move page_mapcount() to fs/proc/internal.h". With all other page_mapcount() users in the tree gone, move page_mapcount() to fs/proc/internal.h, rename it and extend the documentation to prevent future (ab)use. ... of course, I find some issues while working on that code that I sort first ;) We'll now only end up calling page_mapcount() [now folio_precise_page_mapcount()] on pages mapped via present page table entries. Except for /proc/kpagecount, that still does questionable things, but we'll leave that legacy interface as is for now. Did a quick sanity check. Likely we would want some better selfestest for /proc/$/pagemap + smaps. I'll see if I can find some time to write some more. This patch (of 6): Looks like we never taught pagemap_pmd_range() about the existence of PMD-mapped file THPs. Seems to date back to the times when we first added support for non-anon THPs in the form of shmem THP. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Fixes: 800d8c63b2e9 ("shmem: add huge pages support") Acked-by: Kirill A. Shutemov <[email protected]> Reviewed-by: Lance Yang <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Alexey Dobriyan <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03mm: remove MIGRATE_SYNC_NO_COPY modeKefeng Wang2-15/+2
Commit 2916ecc0f9d4 ("mm/migrate: new migrate mode MIGRATE_SYNC_NO_COPY") introduce a new MIGRATE_SYNC_NO_COPY mode to allow to offload the copy to a device DMA engine, which is only used __migrate_device_pages() to decide whether or not copy the old page, and the MIGRATE_SYNC_NO_COPY mode only set in hmm, as the MIGRATE_SYNC_NO_COPY set is removed by previous cleanup, it seems that we could remove the unnecessary MIGRATE_SYNC_NO_COPY. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kefeng Wang <[email protected]> Reviewed-by: Jane Chu <[email protected]> Cc: Alistair Popple <[email protected]> Cc: Benjamin LaHaise <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jérôme Glisse <[email protected]> Cc: Jiaqi Yan <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: Miaohe Lin <[email protected]> Cc: Muchun Song <[email protected]> Cc: Naoya Horiguchi <[email protected]> Cc: Tony Luck <[email protected]> Cc: Vishal Moola (Oracle) <[email protected]> Cc: Zi Yan <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03nfs: drop usage of folio_file_posKairui Song3-6/+6
folio_file_pos is only needed for mixed usage of page cache and swap cache, for pure page cache usage, the caller can just use folio_pos instead. After commit e1209d3a7a67 ("mm: introduce ->swap_rw and use it for reads from SWP_FS_OPS swap-space"), swap cache should never be exposed to nfs. So remove the usage of folio_file_pos in following NFS functions / helpers: - nfs_vm_page_mkwrite It's only used by nfs_file_vm_ops.page_mkwrite - trace event helper: nfs_folio_event - trace event helper: nfs_folio_event_done These two are used through DEFINE_NFS_FOLIO_EVENT and DEFINE_NFS_FOLIO_EVENT_DONE, which defined following events: - trace_nfs_aop_readpage{_done}: only called by nfs_read_folio - trace_nfs_writeback_folio: only called by nfs_wb_folio - trace_nfs_invalidate_folio: only called by nfs_invalidate_folio - trace_nfs_launder_folio_done: only called by nfs_launder_folio None of them could possibly be used on swap cache folio, nfs_read_folio only called by: .write_begin -> nfs_read_folio .read_folio nfs_wb_folio only called by nfs mapping: .release_folio -> nfs_wb_folio .launder_folio -> nfs_wb_folio .write_begin -> nfs_read_folio -> nfs_wb_folio .read_folio -> nfs_wb_folio .write_end -> nfs_update_folio -> nfs_writepage_setup -> nfs_setup_write_request -> nfs_try_to_update_request -> nfs_wb_folio .page_mkwrite -> nfs_update_folio -> nfs_writepage_setup -> nfs_setup_write_request -> nfs_try_to_update_request -> nfs_wb_folio .write_begin -> nfs_flush_incompatible -> nfs_wb_folio .page_mkwrite -> nfs_vm_page_mkwrite -> nfs_flush_incompatible -> nfs_wb_folio nfs_invalidate_folio is only called by .invalidate_folio. nfs_launder_folio is only called by .launder_folio - nfs_grow_file - nfs_update_folio nfs_grow_file is only called by nfs_update_folio, and all possible callers of them are: .write_end -> nfs_update_folio .page_mkwrite -> nfs_update_folio - nfs_wb_folio_cancel .invalidate_folio -> nfs_wb_folio_cancel Also, seeing from the swap side, swap_rw is now the only interface calling into fs, the offset info is always in iocb.ki_pos now. So we can remove all these folio_file_pos call safely. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kairui Song <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Anna Schumaker <[email protected]> Cc: Barry Song <[email protected]> Cc: Chao Yu <[email protected]> Cc: Chris Li <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Howells <[email protected]> Cc: "Huang, Ying" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Ilya Dryomov <[email protected]> Cc: Jaegeuk Kim <[email protected]> Cc: Jeff Layton <[email protected]> Cc: Marc Dionne <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: Minchan Kim <[email protected]> Cc: NeilBrown <[email protected]> Cc: Ryan Roberts <[email protected]> Cc: Ryusuke Konishi <[email protected]> Cc: Xiubo Li <[email protected]> Cc: Yosry Ahmed <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03netfs: drop usage of folio_file_posKairui Song2-3/+3
folio_file_pos is only needed for mixed usage of page cache and swap cache, for pure page cache usage, the caller can just use folio_pos instead. It can't be a swap cache page here. Swap mapping may only call into fs through swap_rw and that is not supported for netfs. So just drop it and use folio_pos instead. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kairui Song <[email protected]> Cc: David Howells <[email protected]> Cc: Jeff Layton <[email protected]> Cc: Anna Schumaker <[email protected]> Cc: Barry Song <[email protected]> Cc: Chao Yu <[email protected]> Cc: Chris Li <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: "Huang, Ying" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Ilya Dryomov <[email protected]> Cc: Jaegeuk Kim <[email protected]> Cc: Marc Dionne <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: Minchan Kim <[email protected]> Cc: NeilBrown <[email protected]> Cc: Ryan Roberts <[email protected]> Cc: Ryusuke Konishi <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Xiubo Li <[email protected]> Cc: Yosry Ahmed <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03afs: drop usage of folio_file_posKairui Song2-5/+5
folio_file_pos is only needed for mixed usage of page cache and swap cache, for pure page cache usage, the caller can just use folio_pos instead. It can't be a swap cache page here. Swap mapping may only call into fs through swap_rw and that is not supported for afs. So just drop it and use folio_pos instead. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kairui Song <[email protected]> Cc: David Howells <[email protected]> Cc: Marc Dionne <[email protected]> Cc: Anna Schumaker <[email protected]> Cc: Barry Song <[email protected]> Cc: Chao Yu <[email protected]> Cc: Chris Li <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: "Huang, Ying" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Ilya Dryomov <[email protected]> Cc: Jaegeuk Kim <[email protected]> Cc: Jeff Layton <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: Minchan Kim <[email protected]> Cc: NeilBrown <[email protected]> Cc: Ryan Roberts <[email protected]> Cc: Ryusuke Konishi <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Xiubo Li <[email protected]> Cc: Yosry Ahmed <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03NFS: remove nfs_page_lengthg and usage of page_indexKairui Song1-19/+0
This function is no longer used after commit 4fa7a717b432 ("NFS: Fix up nfs_vm_page_mkwrite() for folios"), all users have been converted to use folio instead, just delete it to remove usage of page_index. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kairui Song <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Anna Schumaker <[email protected]> Cc: Barry Song <[email protected]> Cc: Chao Yu <[email protected]> Cc: Chris Li <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Howells <[email protected]> Cc: "Huang, Ying" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Ilya Dryomov <[email protected]> Cc: Jaegeuk Kim <[email protected]> Cc: Jeff Layton <[email protected]> Cc: Marc Dionne <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: Minchan Kim <[email protected]> Cc: NeilBrown <[email protected]> Cc: Ryan Roberts <[email protected]> Cc: Ryusuke Konishi <[email protected]> Cc: Xiubo Li <[email protected]> Cc: Yosry Ahmed <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03ceph: drop usage of page_indexKairui Song2-2/+2
page_index is needed for mixed usage of page cache and swap cache, for pure page cache usage, the caller can just use page->index instead. It can't be a swap cache page here, so just drop it. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kairui Song <[email protected]> Cc: Xiubo Li <[email protected]> Cc: Ilya Dryomov <[email protected]> Cc: Jeff Layton <[email protected]> Cc: Anna Schumaker <[email protected]> Cc: Barry Song <[email protected]> Cc: Chao Yu <[email protected]> Cc: Chris Li <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Howells <[email protected]> Cc: "Huang, Ying" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jaegeuk Kim <[email protected]> Cc: Marc Dionne <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: Minchan Kim <[email protected]> Cc: NeilBrown <[email protected]> Cc: Ryan Roberts <[email protected]> Cc: Ryusuke Konishi <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Yosry Ahmed <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03nilfs2: drop usage of page_indexKairui Song1-8/+2
Patch series "mm/swap: clean up and optimize swap cache index", v6. Currently we use one swap_address_space for every 64M chunk to reduce lock contention, this is like having a set of smaller files inside a swap device. But when doing swap cache look up or insert, we are still using the offset of the whole large swap device. This is OK for correctness, as the offset (key) is unique. But Xarray is specially optimized for small indexes, it creates the redix tree levels lazily to be just enough to fit the largest key stored in one Xarray. So we are wasting tree nodes unnecessarily. For 64M chunk it should only take at most 3 level to contain everything. But if we are using the offset from the whole swap device, the offset (key) value will be way beyond 64M, and so will the tree level. Optimize this by reduce the swap cache search space into 64M scope. Test with `time memhog 128G` inside a 8G memcg using 128G swap (ramdisk with SWP_SYNCHRONOUS_IO dropped, tested 3 times, results are stable. The test result is similar but the improvement is smaller if SWP_SYNCHRONOUS_IO is enabled, as swap out path can never skip swap cache): Before: 6.07user 250.74system 4:17.26elapsed 99%CPU (0avgtext+0avgdata 8373376maxresident)k 0inputs+0outputs (55major+33555018minor)pagefaults 0swaps After (+1.8% faster): 6.08user 246.09system 4:12.58elapsed 99%CPU (0avgtext+0avgdata 8373248maxresident)k 0inputs+0outputs (54major+33555027minor)pagefaults 0swaps Similar result with MySQL and sysbench using swap: Before: 94055.61 qps After (+0.8% faster): 94834.91 qps There is alse a very slight drop of radix tree node slab usage: Before: 303952K After: 302224K For this series: There are multiple places that expect mixed type of pages (page cache or swap cache), eg. migration, huge memory split; There are four helpers for that: - page_index - page_file_offset - folio_index - folio_file_pos To keep the code clean and compatible, this series first cleaned up usage of them. page_file_offset and folio_file_pos are historical helpes that can be simply dropped after clean up. And page_index can be all converted to folio_index or folio->index. Then introduce two new helpers swap_cache_index and swap_dev_pos for swap. Replace swp_offset with swap_cache_index when used to retrieve folio from swap cache, and use swap_dev_pos when needed to retrieve the device position of a swap entry. This way, swap_cache_index can return the optimized value with no compatibility issue. The result is better performance and reduced LOC. Idealy, in the future, we may want to reduce SWAP_ADDRESS_SPACE_SHIFT from 14 to 12: Default Xarray chunk offset is 6, so we have 3 level trees instead of 2 level trees just for 2 extra bits. But swap cache is based on address_space struct, with 4 times more metadata sparsely distributed in memory it waste more cacheline, the performance gain from this series is almost canceled according to my test. So first, just have a cleaner seperation of offsets and smaller search space. This patch (of 10): page_index is only for mixed usage of page cache and swap cache, for pure page cache usage, the caller can just use page->index instead. It can't be a swap cache page here (being part of buffer head), so just drop it. And while we are at it, optimize the code by retrieving the offset of the buffer head within the folio directly using bh_offset, and get rid of the loop and usage of page helpers. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Suggested-by: Matthew Wilcox <[email protected]> Signed-off-by: Kairui Song <[email protected]> Acked-by: Ryusuke Konishi <[email protected]> Cc: Ryusuke Konishi <[email protected]> Cc: Anna Schumaker <[email protected]> Cc: Barry Song <[email protected]> Cc: Chao Yu <[email protected]> Cc: Chris Li <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Howells <[email protected]> Cc: "Huang, Ying" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Ilya Dryomov <[email protected]> Cc: Jaegeuk Kim <[email protected]> Cc: Jeff Layton <[email protected]> Cc: Marc Dionne <[email protected]> Cc: Minchan Kim <[email protected]> Cc: NeilBrown <[email protected]> Cc: Ryan Roberts <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Xiubo Li <[email protected]> Cc: Yosry Ahmed <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-04btrfs: fix folio refcount in __alloc_dummy_extent_buffer()Boris Burkov1-1/+1
Another improper use of __folio_put() in an error path after freshly allocating pages/folios which returns them with the refcount initialized to 1. The refactor from __free_pages() -> __folio_put() (instead of folio_put) removed a refcount decrement found in __free_pages() and folio_put but absent from __folio_put(). Fixes: 13df3775efca ("btrfs: cleanup metadata page pointer usage") CC: [email protected] # 6.8+ Tested-by: Ed Tomlinson <[email protected]> Reviewed-by: Filipe Manana <[email protected]> Signed-off-by: Boris Burkov <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]>
2024-07-04btrfs: fix folio refcount in btrfs_do_encoded_write()Boris Burkov1-1/+1
The conversion to folios switched __free_page() to __folio_put() in the error path in btrfs_do_encoded_write(). However, this gets the page refcounting wrong. If we do hit that error path (I reproduced by modifying btrfs_do_encoded_write to pretend to always fail in a way that jumps to out_folios and running the fstests case btrfs/281), then we always hit the following BUG freeing the folio: BUG: Bad page state in process btrfs pfn:40ab0b page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x61be5 pfn:0x40ab0b flags: 0x5ffff0000000000(node=0|zone=2|lastcpupid=0x1ffff) raw: 05ffff0000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000061be5 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: nonzero _refcount Call Trace: <TASK> dump_stack_lvl+0x3d/0xe0 bad_page+0xea/0xf0 free_unref_page+0x8e1/0x900 ? __mem_cgroup_uncharge+0x69/0x90 __folio_put+0xe6/0x190 btrfs_do_encoded_write+0x445/0x780 ? current_time+0x25/0xd0 btrfs_do_write_iter+0x2cc/0x4b0 btrfs_ioctl_encoded_write+0x2b6/0x340 It turns out __free_page() decreases the page reference count while __folio_put() does not. Switch __folio_put() to folio_put() which decreases the folio reference count first. Fixes: 400b172b8cdc ("btrfs: compression: migrate compression/decompression paths to folios") Tested-by: Ed Tomlinson <[email protected]> Reviewed-by: Qu Wenruo <[email protected]> Reviewed-by: Filipe Manana <[email protected]> Signed-off-by: Boris Burkov <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]>
2024-07-03nilfs2: fix incorrect inode allocation from reserved inodesRyusuke Konishi4-12/+20
If the bitmap block that manages the inode allocation status is corrupted, nilfs_ifile_create_inode() may allocate a new inode from the reserved inode area where it should not be allocated. Previous fix commit d325dc6eb763 ("nilfs2: fix use-after-free bug of struct nilfs_root"), fixed the problem that reserved inodes with inode numbers less than NILFS_USER_INO (=11) were incorrectly reallocated due to bitmap corruption, but since the start number of non-reserved inodes is read from the super block and may change, in which case inode allocation may occur from the extended reserved inode area. If that happens, access to that inode will cause an IO error, causing the file system to degrade to an error state. Fix this potential issue by adding a wraparound option to the common metadata object allocation routine and by modifying nilfs_ifile_create_inode() to disable the option so that it only allocates inodes with inode numbers greater than or equal to the inode number read in "nilfs->ns_first_ino", regardless of the bitmap status of reserved inodes. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Ryusuke Konishi <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Jan Kara <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03nilfs2: add missing check for inode numbers on directory entriesRyusuke Konishi2-0/+11
Syzbot reported that mounting and unmounting a specific pattern of corrupted nilfs2 filesystem images causes a use-after-free of metadata file inodes, which triggers a kernel bug in lru_add_fn(). As Jan Kara pointed out, this is because the link count of a metadata file gets corrupted to 0, and nilfs_evict_inode(), which is called from iput(), tries to delete that inode (ifile inode in this case). The inconsistency occurs because directories containing the inode numbers of these metadata files that should not be visible in the namespace are read without checking. Fix this issue by treating the inode numbers of these internal files as errors in the sanity check helper when reading directory folios/pages. Also thanks to Hillf Danton and Matthew Wilcox for their initial mm-layer analysis. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Ryusuke Konishi <[email protected]> Reported-by: [email protected] Closes: https://syzkaller.appspot.com/bug?extid=d79afb004be235636ee8 Reported-by: Jan Kara <[email protected]> Closes: https://lkml.kernel.org/r/20240617075758.wewhukbrjod5fp5o@quack3 Tested-by: Ryusuke Konishi <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03nilfs2: fix inode number range checksRyusuke Konishi3-3/+10
Patch series "nilfs2: fix potential issues related to reserved inodes". This series fixes one use-after-free issue reported by syzbot, caused by nilfs2's internal inode being exposed in the namespace on a corrupted filesystem, and a couple of flaws that cause problems if the starting number of non-reserved inodes written in the on-disk super block is intentionally (or corruptly) changed from its default value. This patch (of 3): In the current implementation of nilfs2, "nilfs->ns_first_ino", which gives the first non-reserved inode number, is read from the superblock, but its lower limit is not checked. As a result, if a number that overlaps with the inode number range of reserved inodes such as the root directory or metadata files is set in the super block parameter, the inode number test macros (NILFS_MDT_INODE and NILFS_VALID_INODE) will not function properly. In addition, these test macros use left bit-shift calculations using with the inode number as the shift count via the BIT macro, but the result of a shift calculation that exceeds the bit width of an integer is undefined in the C specification, so if "ns_first_ino" is set to a large value other than the default value NILFS_USER_INO (=11), the macros may potentially malfunction depending on the environment. Fix these issues by checking the lower bound of "nilfs->ns_first_ino" and by preventing bit shifts equal to or greater than the NILFS_USER_INO constant in the inode number test macros. Also, change the type of "ns_first_ino" from signed integer to unsigned integer to avoid the need for type casting in comparisons such as the lower bound check introduced this time. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Ryusuke Konishi <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Jan Kara <[email protected]> Cc: Matthew Wilcox (Oracle) <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2024-07-03fuse: Convert to new uid/gid option parsing helpersEric Sandeen1-8/+4
Convert to new uid/gid option parsing helpers Signed-off-by: Eric Sandeen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Reviewed-by: Christian Brauner <[email protected]> Reviewed-by: Josef Bacik <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03fuse: verify {g,u}id mount options correctlyEric Sandeen1-4/+20
As was done in 0200679fc795 ("tmpfs: verify {g,u}id mount options correctly") we need to validate that the requested uid and/or gid is representable in the filesystem's idmapping. Cribbing from the above commit log, The contract for {g,u}id mount options and {g,u}id values in general set from userspace has always been that they are translated according to the caller's idmapping. In so far, fuse has been doing the correct thing. But since fuse is mountable in unprivileged contexts it is also necessary to verify that the resulting {k,g}uid is representable in the namespace of the superblock. Fixes: c30da2e981a7 ("fuse: convert to use the new mount API") Cc: [email protected] # 5.4+ Signed-off-by: Eric Sandeen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Reviewed-by: Christian Brauner <[email protected]> Reviewed-by: Josef Bacik <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03hostfs: add missing MODULE_DESCRIPTION() macroJeff Johnson1-0/+1
With ARCH=um, make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in fs/hostfs/hostfs.o Add the missing invocation of the MODULE_DESCRIPTION() macro. Signed-off-by: Jeff Johnson <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Johannes Berg <[email protected]>
2024-07-03hostfs: fix dev_t handlingJohannes Berg3-10/+14
dev_t is a kernel type and may have different definitions in kernel and userspace. On 32-bit x86 this currently makes the stat structure being 4 bytes longer in the user code, causing stack corruption. However, this is (potentially) not the only problem, since dev_t is a different type on user/kernel side, so we don't know that the major/minor encoding isn't also different. Decode/encode it instead to address both problems. Cc: [email protected] Fixes: 74ce793bcbde ("hostfs: Fix ephemeral inodes") Link: https://patch.msgid.link/20240702092440.acc960585dd5.Id0767e12f562a69c6cd3c3262dc3d765db350cf6@changeid Signed-off-by: Johannes Berg <[email protected]>
2024-07-03fat: Convert to new uid/gid option parsing helpersEric Sandeen1-12/+4
Convert to new uid/gid option parsing helpers Signed-off-by: Eric Sandeen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Acked-by: OGAWA Hirofumi <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03fat: Convert to new mount apiEric Sandeen4-355/+419
vfat and msdos share a common set of options, with additional, unique options for each filesystem. Each filesystem calls common fc initialization and parsing routines, with an "is_vfat" parameter. For parsing, if the option is not found in the common parameter_spec, parsing is retried with the fs-specific parameter_spec. This patch leaves nls loading to fill_super, so the codepage and charset options are not validated as they are requested. This matches current behavior. It would be possible to test-load as each option is parsed, but that would make i.e. mount -o "iocharset=nope,iocharset=iso8859-1" fail, where it does not fail today because only the last iocharset option is considered. The obsolete "conv=" option is set up with an enum of acceptable values; currently invalid "conv=" options are rejected as such, even though the option is obsolete, so this patch preserves that behavior. Signed-off-by: Eric Sandeen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Acked-by: OGAWA Hirofumi <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03fat: move debug into fat_mount_optionsEric Sandeen2-6/+6
Move the debug variable into fat_mount_options for consistency and to facilitate conversion to new mount API. Signed-off-by: Eric Sandeen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Acked-by: OGAWA Hirofumi <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03cachefiles: add missing lock protection when pollingJingbo Xu1-2/+2
Add missing lock protection in poll routine when iterating xarray, otherwise: Even with RCU read lock held, only the slot of the radix tree is ensured to be pinned there, while the data structure (e.g. struct cachefiles_req) stored in the slot has no such guarantee. The poll routine will iterate the radix tree and dereference cachefiles_req accordingly. Thus RCU read lock is not adequate in this case and spinlock is needed here. Fixes: b817e22b2e91 ("cachefiles: narrow the scope of triggering EPOLLIN events in ondemand mode") Signed-off-by: Jingbo Xu <[email protected]> Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Acked-by: Jeff Layton <[email protected]> Reviewed-by: Jia Zhu <[email protected]> Reviewed-by: Gao Xiang <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03cachefiles: cyclic allocation of msg_id to avoid reuseBaokun Li2-4/+17
Reusing the msg_id after a maliciously completed reopen request may cause a read request to remain unprocessed and result in a hung, as shown below: t1 | t2 | t3 ------------------------------------------------- cachefiles_ondemand_select_req cachefiles_ondemand_object_is_close(A) cachefiles_ondemand_set_object_reopening(A) queue_work(fscache_object_wq, &info->work) ondemand_object_worker cachefiles_ondemand_init_object(A) cachefiles_ondemand_send_req(OPEN) // get msg_id 6 wait_for_completion(&req_A->done) cachefiles_ondemand_daemon_read // read msg_id 6 req_A cachefiles_ondemand_get_fd copy_to_user // Malicious completion msg_id 6 copen 6,-1 cachefiles_ondemand_copen complete(&req_A->done) // will not set the object to close // because ondemand_id && fd is valid. // ondemand_object_worker() is done // but the object is still reopening. // new open req_B cachefiles_ondemand_init_object(B) cachefiles_ondemand_send_req(OPEN) // reuse msg_id 6 process_open_req copen 6,A.size // The expected failed copen was executed successfully Expect copen to fail, and when it does, it closes fd, which sets the object to close, and then close triggers reopen again. However, due to msg_id reuse resulting in a successful copen, the anonymous fd is not closed until the daemon exits. Therefore read requests waiting for reopen to complete may trigger hung task. To avoid this issue, allocate the msg_id cyclically to avoid reusing the msg_id for a very short duration of time. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Acked-by: Jeff Layton <[email protected]> Reviewed-by: Gao Xiang <[email protected]> Reviewed-by: Jia Zhu <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03cachefiles: wait for ondemand_object_worker to finish when dropping objectHou Tao1-0/+3
When queuing ondemand_object_worker() to re-open the object, cachefiles_object is not pinned. The cachefiles_object may be freed when the pending read request is completed intentionally and the related erofs is umounted. If ondemand_object_worker() runs after the object is freed, it will incur use-after-free problem as shown below. process A processs B process C process D cachefiles_ondemand_send_req() // send a read req X // wait for its completion // close ondemand fd cachefiles_ondemand_fd_release() // set object as CLOSE cachefiles_ondemand_daemon_read() // set object as REOPENING queue_work(fscache_wq, &info->ondemand_work) // close /dev/cachefiles cachefiles_daemon_release cachefiles_flush_reqs complete(&req->done) // read req X is completed // umount the erofs fs cachefiles_put_object() // object will be freed cachefiles_ondemand_deinit_obj_info() kmem_cache_free(object) // both info and object are freed ondemand_object_worker() When dropping an object, it is no longer necessary to reopen the object, so use cancel_work_sync() to cancel or wait for ondemand_object_worker() to finish. Fixes: 0a7e54c1959c ("cachefiles: resend an open request if the read request's object is closed") Signed-off-by: Hou Tao <[email protected]> Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Acked-by: Jeff Layton <[email protected]> Reviewed-by: Jia Zhu <[email protected]> Reviewed-by: Gao Xiang <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03cachefiles: cancel all requests for the object that is being droppedBaokun Li1-0/+19
Because after an object is dropped, requests for that object are useless, cancel them to avoid causing other problems. This prepares for the later addition of cancel_work_sync(). After the reopen requests is generated, cancel it to avoid cancel_work_sync() blocking by waiting for daemon to complete the reopen requests. Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Acked-by: Jeff Layton <[email protected]> Reviewed-by: Gao Xiang <[email protected]> Reviewed-by: Jia Zhu <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03cachefiles: stop sending new request when dropping objectBaokun Li2-2/+10
Added CACHEFILES_ONDEMAND_OBJSTATE_DROPPING indicates that the cachefiles object is being dropped, and is set after the close request for the dropped object completes, and no new requests are allowed to be sent after this state. This prepares for the later addition of cancel_work_sync(). It prevents leftover reopen requests from being sent, to avoid processing unnecessary requests and to avoid cancel_work_sync() blocking by waiting for daemon to complete the reopen requests. Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Acked-by: Jeff Layton <[email protected]> Reviewed-by: Gao Xiang <[email protected]> Reviewed-by: Jia Zhu <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03cachefiles: propagate errors from vfs_getxattr() to avoid infinite loopBaokun Li1-1/+4
In cachefiles_check_volume_xattr(), the error returned by vfs_getxattr() is not passed to ret, so it ends up returning -ESTALE, which leads to an endless loop as follows: cachefiles_acquire_volume retry: ret = cachefiles_check_volume_xattr ret = -ESTALE xlen = vfs_getxattr // return -EIO // The ret is not updated when xlen < 0, so -ESTALE is returned. return ret // Supposed to jump out of the loop at this judgement. if (ret != -ESTALE) goto error_dir; cachefiles_bury_object // EIO causes rename failure goto retry; Hence propagate the error returned by vfs_getxattr() to avoid the above issue. Do the same in cachefiles_check_auxdata(). Fixes: 32e150037dce ("fscache, cachefiles: Store the volume coherency data") Fixes: 72b957856b0c ("cachefiles: Implement metadata/coherency data storage in xattrs") Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Reviewed-by: Gao Xiang <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-03cachefiles: fix slab-use-after-free in cachefiles_withdraw_cookie()Baokun Li2-2/+34
We got the following issue in our fault injection stress test: ================================================================== BUG: KASAN: slab-use-after-free in cachefiles_withdraw_cookie+0x4d9/0x600 Read of size 8 at addr ffff888118efc000 by task kworker/u78:0/109 CPU: 13 PID: 109 Comm: kworker/u78:0 Not tainted 6.8.0-dirty #566 Call Trace: <TASK> kasan_report+0x93/0xc0 cachefiles_withdraw_cookie+0x4d9/0x600 fscache_cookie_state_machine+0x5c8/0x1230 fscache_cookie_worker+0x91/0x1c0 process_one_work+0x7fa/0x1800 [...] Allocated by task 117: kmalloc_trace+0x1b3/0x3c0 cachefiles_acquire_volume+0xf3/0x9c0 fscache_create_volume_work+0x97/0x150 process_one_work+0x7fa/0x1800 [...] Freed by task 120301: kfree+0xf1/0x2c0 cachefiles_withdraw_cache+0x3fa/0x920 cachefiles_put_unbind_pincount+0x1f6/0x250 cachefiles_daemon_release+0x13b/0x290 __fput+0x204/0xa00 task_work_run+0x139/0x230 do_exit+0x87a/0x29b0 [...] ================================================================== Following is the process that triggers the issue: p1 | p2 ------------------------------------------------------------ fscache_begin_lookup fscache_begin_volume_access fscache_cache_is_live(fscache_cache) cachefiles_daemon_release cachefiles_put_unbind_pincount cachefiles_daemon_unbind cachefiles_withdraw_cache fscache_withdraw_cache fscache_set_cache_state(cache, FSCACHE_CACHE_IS_WITHDRAWN); cachefiles_withdraw_objects(cache) fscache_wait_for_objects(fscache) atomic_read(&fscache_cache->object_count) == 0 fscache_perform_lookup cachefiles_lookup_cookie cachefiles_alloc_object refcount_set(&object->ref, 1); object->volume = volume fscache_count_object(vcookie->cache); atomic_inc(&fscache_cache->object_count) cachefiles_withdraw_volumes cachefiles_withdraw_volume fscache_withdraw_volume __cachefiles_free_volume kfree(cachefiles_volume) fscache_cookie_state_machine cachefiles_withdraw_cookie cache = object->volume->cache; // cachefiles_volume UAF !!! After setting FSCACHE_CACHE_IS_WITHDRAWN, wait for all the cookie lookups to complete first, and then wait for fscache_cache->object_count == 0 to avoid the cookie exiting after the volume has been freed and triggering the above issue. Therefore call fscache_withdraw_volume() before calling cachefiles_withdraw_objects(). This way, after setting FSCACHE_CACHE_IS_WITHDRAWN, only the following two cases will occur: 1) fscache_begin_lookup fails in fscache_begin_volume_access(). 2) fscache_withdraw_volume() will ensure that fscache_count_object() has been executed before calling fscache_wait_for_objects(). Fixes: fe2140e2f57f ("cachefiles: Implement volume support") Suggested-by: Hou Tao <[email protected]> Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Christian Brauner <[email protected]>
2024-07-03cachefiles: fix slab-use-after-free in fscache_withdraw_volume()Baokun Li1-0/+10
We got the following issue in our fault injection stress test: ================================================================== BUG: KASAN: slab-use-after-free in fscache_withdraw_volume+0x2e1/0x370 Read of size 4 at addr ffff88810680be08 by task ondemand-04-dae/5798 CPU: 0 PID: 5798 Comm: ondemand-04-dae Not tainted 6.8.0-dirty #565 Call Trace: kasan_check_range+0xf6/0x1b0 fscache_withdraw_volume+0x2e1/0x370 cachefiles_withdraw_volume+0x31/0x50 cachefiles_withdraw_cache+0x3ad/0x900 cachefiles_put_unbind_pincount+0x1f6/0x250 cachefiles_daemon_release+0x13b/0x290 __fput+0x204/0xa00 task_work_run+0x139/0x230 Allocated by task 5820: __kmalloc+0x1df/0x4b0 fscache_alloc_volume+0x70/0x600 __fscache_acquire_volume+0x1c/0x610 erofs_fscache_register_volume+0x96/0x1a0 erofs_fscache_register_fs+0x49a/0x690 erofs_fc_fill_super+0x6c0/0xcc0 vfs_get_super+0xa9/0x140 vfs_get_tree+0x8e/0x300 do_new_mount+0x28c/0x580 [...] Freed by task 5820: kfree+0xf1/0x2c0 fscache_put_volume.part.0+0x5cb/0x9e0 erofs_fscache_unregister_fs+0x157/0x1b0 erofs_kill_sb+0xd9/0x1c0 deactivate_locked_super+0xa3/0x100 vfs_get_super+0x105/0x140 vfs_get_tree+0x8e/0x300 do_new_mount+0x28c/0x580 [...] ================================================================== Following is the process that triggers the issue: mount failed | daemon exit ------------------------------------------------------------ deactivate_locked_super cachefiles_daemon_release erofs_kill_sb erofs_fscache_unregister_fs fscache_relinquish_volume __fscache_relinquish_volume fscache_put_volume(fscache_volume, fscache_volume_put_relinquish) zero = __refcount_dec_and_test(&fscache_volume->ref, &ref); cachefiles_put_unbind_pincount cachefiles_daemon_unbind cachefiles_withdraw_cache cachefiles_withdraw_volumes list_del_init(&volume->cache_link) fscache_free_volume(fscache_volume) cache->ops->free_volume cachefiles_free_volume list_del_init(&cachefiles_volume->cache_link); kfree(fscache_volume) cachefiles_withdraw_volume fscache_withdraw_volume fscache_volume->n_accesses // fscache_volume UAF !!! The fscache_volume in cache->volumes must not have been freed yet, but its reference count may be 0. So use the new fscache_try_get_volume() helper function try to get its reference count. If the reference count of fscache_volume is 0, fscache_put_volume() is freeing it, so wait for it to be removed from cache->volumes. If its reference count is not 0, call cachefiles_withdraw_volume() with reference count protection to avoid the above issue. Fixes: fe2140e2f57f ("cachefiles: Implement volume support") Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Christian Brauner <[email protected]>
2024-07-03netfs, fscache: export fscache_put_volume() and add fscache_try_get_volume()Baokun Li2-2/+14
Export fscache_put_volume() and add fscache_try_get_volume() helper function to allow cachefiles to get/put fscache_volume via linux/fscache-cache.h. Signed-off-by: Baokun Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Christian Brauner <[email protected]>
2024-07-02cifs: Fix read-performance regression by dropping readahead expansionDavid Howells1-30/+0
cifs_expand_read() is causing a performance regression of around 30% by causing extra pagecache to be allocated for an inode in the readahead path before we begin actually dispatching RPC requests, thereby delaying the actual I/O. The expansion is sized according to the rsize parameter, which seems to be 4MiB on my test system; this is a big step up from the first requests made by the fio test program. Simple repro (look at read bandwidth number): fio --name=writetest --filename=/xfstest.test/foo --time_based --runtime=60 --size=16M --numjobs=1 --rw=read Fix this by removing cifs_expand_readahead(). Readahead expansion is mostly useful for when we're using the local cache if the local cache has a block size greater than PAGE_SIZE, so we can dispense with it when not caching. Fixes: 69c3c023af25 ("cifs: Implement netfslib hooks") Signed-off-by: David Howells <[email protected]> Acked-by: Paulo Alcantara (Red Hat) <[email protected]> cc: Jeff Layton <[email protected]> cc: Matthew Wilcox <[email protected]> cc: [email protected] cc: [email protected] cc: [email protected] cc: [email protected] Signed-off-by: Steve French <[email protected]>
2024-07-02Merge tag 'vfs-6.10-rc7.fixes.2' of ↵Linus Torvalds3-24/+20
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fixes from Christian Brauner: "VFS: - Improve handling of deep ancestor chains in is_subdir() - Release locks cleanly when fctnl_setlk() races with close(). When setting a file lock fails the VFS tries to cleanup the already created lock. The helper used for this calls back into the LSM layer which may cause it to fail, leaving the stale lock accessible via /proc/locks. AFS: - Fix a comma/semicolon typo" * tag 'vfs-6.10-rc7.fixes.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: afs: Convert comma to semicolon fs: better handle deep ancestor chains in is_subdir() filelock: Remove locks reliably when fcntl/close race is detected
2024-07-02afs: Convert comma to semicolonChen Ni1-2/+2
Replace a comma between expression statements by a semicolon. Signed-off-by: Chen Ni <[email protected]> Link: https://lore.kernel.org/r/[email protected]/ Link: https://lore.kernel.org/r/[email protected] Acked-by: David Howells <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-02fs: better handle deep ancestor chains in is_subdir()Christian Brauner1-17/+14
Jan reported that 'cd ..' may take a long time in deep directory hierarchies under a bind-mount. If concurrent renames happen it is possible to livelock in is_subdir() because it will keep retrying. Change is_subdir() from simply retrying over and over to retry once and then acquire the rename lock to handle deep ancestor chains better. The list of alternatives to this approach were less then pleasant. Change the scope of rcu lock to cover the whole walk while at it. A big thanks to Jan and Linus. Both Jan and Linus had proposed effectively the same thing just that one version ended up being slightly more elegant. Reported-by: Jan Kara <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-02Merge tag 'erofs-for-6.10-rc7-fixes' of ↵Linus Torvalds3-5/+7
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs fixes from Gao Xiang: "The most important one fixes possible infinite loops reported by a smartphone vendor OPPO recently due to some unexpected zero-sized compressed pcluster out of interrupted I/Os, storage failures, etc. Another patch fixes global buffer memory leak on unloading, and the remaining one switches to use super_set_uuid() to keep with the other filesystems. Summary: - Fix possible global buffer memory leak when unloading EROFS module - Fix FS_IOC_GETFSUUID ioctl by using super_set_uuid() - Reset m_llen to 0 so then it can retry if metadata is invalid" * tag 'erofs-for-6.10-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: ensure m_llen is reset to 0 if metadata is invalid erofs: convert to use super_set_uuid to support for FS_IOC_GETFSUUID erofs: fix possible memory leak in z_erofs_gbuf_exit()
2024-07-02filelock: Remove locks reliably when fcntl/close race is detectedJann Horn1-5/+4
When fcntl_setlk() races with close(), it removes the created lock with do_lock_file_wait(). However, LSMs can allow the first do_lock_file_wait() that created the lock while denying the second do_lock_file_wait() that tries to remove the lock. In theory (but AFAIK not in practice), posix_lock_file() could also fail to remove a lock due to GFP_KERNEL allocation failure (when splitting a range in the middle). After the bug has been triggered, use-after-free reads will occur in lock_get_status() when userspace reads /proc/locks. This can likely be used to read arbitrary kernel memory, but can't corrupt kernel memory. This only affects systems with SELinux / Smack / AppArmor / BPF-LSM in enforcing mode and only works from some security contexts. Fix it by calling locks_remove_posix() instead, which is designed to reliably get rid of POSIX locks associated with the given file and files_struct and is also used by filp_flush(). Fixes: c293621bbf67 ("[PATCH] stale POSIX lock handling") Cc: [email protected] Link: https://bugs.chromium.org/p/project-zero/issues/detail?id=2563 Signed-off-by: Jann Horn <[email protected]> Link: https://lore.kernel.org/r/[email protected] Reviewed-by: Jeff Layton <[email protected]> Signed-off-by: Christian Brauner <[email protected]>
2024-07-02xfs: move xfs_refcount_update_defer_add to xfs_refcount_item.cDarrick J. Wong4-20/+18
Move the code that adds the incore xfs_refcount_update_item deferred work data to a transaction live with the CUI log item code. This means that the refcount code no longer has to know about the inner workings of the CUI log items. As a consequence, we can get rid of the _{get,put}_group helpers. Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]>
2024-07-02xfs: simplify usage of the rcur local variable in xfs_refcount_finish_oneDarrick J. Wong1-4/+3
Only update rcur when we know the final *pcur value. Inspired-by: Christoph Hellwig <[email protected]> [djwong: don't leave the caller with a dangling ref] Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]>
2024-07-02xfs: don't bother calling xfs_refcount_finish_one_cleanup in ↵Darrick J. Wong3-20/+19
xfs_refcount_finish_one In xfs_refcount_finish_one we know the cursor is non-zero when calling xfs_refcount_finish_one_cleanup and we pass a 0 error variable. This means xfs_refcount_finish_one_cleanup is just doing a xfs_btree_del_cursor. Open code that and move xfs_refcount_finish_one_cleanup to fs/xfs/xfs_refcount_item.c. Inspired-by: Christoph Hellwig <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]>
2024-07-02xfs: reuse xfs_refcount_update_cancel_itemDarrick J. Wong1-13/+12
Reuse xfs_refcount_update_cancel_item to put the AG/RTG and free the item in a few places that currently open code the logic. Inspired-by: Christoph Hellwig <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]>
2024-07-02xfs: add a ci_entry helperDarrick J. Wong1-11/+9
Add a helper to translate from the item list head to the refcount_intent_item structure and use it so shorten assignments and avoid the need for extra local variables. Inspired-by: Christoph Hellwig <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]>
2024-07-02xfs: remove xfs_trans_set_refcount_flagsDarrick J. Wong1-20/+12
Remove this single-use helper. Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]>