laptop-kernel/fs/fuse, branch master

fuse: fuse_dev_ioctl_clone() should wait for device file to be initialized

2026-04-27T13:30:17Z

commit da6fcc6dbddbef80e603d2f0c1554a9f2ac03742 upstream. Use fuse_get_dev() not __fuse_get_dev() on the old fd, since in the case of synchronous INIT the caller will want to wait for the device file to be available for cloning, just like I/O wants to wait instead of returning an error. Fixes: dfb84c330794 ("fuse: allow synchronous FUSE_INIT") Cc: stable@vger.kernel.org # v6.18 Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: quiet down complaints in fuse_conn_limit_write

2026-04-27T13:30:17Z

commit 129a45f9755a89f573c6a513a6b9e3d234ce89b0 upstream. gcc 15 complains about an uninitialized variable val that is passed by reference into fuse_conn_limit_write: control.c: In function ‘fuse_conn_congestion_threshold_write’: include/asm-generic/rwonce.h:55:37: warning: ‘val’ may be used uninitialized [-Wmaybe-uninitialized] 55 | *(volatile typeof(x) *)&(x) = (val); \ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~ include/asm-generic/rwonce.h:61:9: note: in expansion of macro ‘__WRITE_ONCE’ 61 | __WRITE_ONCE(x, val); \ | ^~~~~~~~~~~~ control.c:178:9: note: in expansion of macro ‘WRITE_ONCE’ 178 | WRITE_ONCE(fc->congestion_threshold, val); | ^~~~~~~~~~ control.c:166:18: note: ‘val’ was declared here 166 | unsigned val; | ^~~ Unfortunately there's enough macro spew involved in kstrtoul_from_user that I think gcc gives up on its analysis and sprays the above warning. AFAICT it's not actually a bug, but we could just zero-initialize the variable to enable using -Wmaybe-uninitialized to find real problems. Previously we would use some weird uninitialized_var annotation to quiet down the warnings, so clearly this code has been like this for quite some time. Cc: stable@vger.kernel.org # v5.9 Fixes: 3f649ab728cda8 ("treewide: Remove uninitialized_var() usage") Signed-off-by: Darrick J. Wong Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: Check for large folio with SPLICE_F_MOVE

2026-04-27T13:30:17Z

commit 59ba47b6be9cd0146ef9a55c6e32e337e11e7625 upstream. xfstest generic/074 and generic/075 complain result in kernel warning messages / page dumps. This is easily reproducible (on 6.19) with CONFIG_TRANSPARENT_HUGEPAGE_SHMEM_HUGE_ALWAYS=y CONFIG_TRANSPARENT_HUGEPAGE_TMPFS_HUGE_ALWAYS=y This just adds a test for large folios fuse_try_move_folio with the same page copy fallback, but to avoid the warnings from fuse_check_folio(). Cc: stable@vger.kernel.org Signed-off-by: Bernd Schubert Signed-off-by: Horst Birthelmer Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: abort on fatal signal during sync init

2026-04-27T13:30:17Z

commit 204aa22a686bfee48daca7db620c1e017615f2ff upstream. When sync init is used and the server exits for some reason (error, crash) while processing FUSE_INIT, the filesystem creation will hang. The reason is that while all other threads will exit, the mounting thread (or process) will keep the device fd open, which will prevent an abort from happening. This is a regression from the async mount case, where the mount was done first, and the FUSE_INIT processing afterwards, in which case there's no such recursive syscall keeping the fd open. Fixes: dfb84c330794 ("fuse: allow synchronous FUSE_INIT") Cc: stable@vger.kernel.org # v6.18 Reviewed-by: Joanne Koong Reviewed-by: Bernd Schubert Reviewed-by: "Darrick J. Wong" Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

fuse: reject oversized dirents in page cache

2026-04-27T13:30:17Z

commit 51a8de6c50bf947c8f534cd73da4c8f0a13e7bed upstream. fuse_add_dirent_to_cache() computes a serialized dirent size from the server-controlled namelen field and copies the dirent into a single page-cache page. The existing logic only checks whether the dirent fits in the remaining space of the current page and advances to a fresh page if not. It never checks whether the dirent itself exceeds PAGE_SIZE. As a result, a malicious FUSE server can return a dirent with namelen=4095, producing a serialized record size of 4120 bytes. On 4 KiB page systems this causes memcpy() to overflow the cache page by 24 bytes into the following kernel page. Reject dirents that cannot fit in a single page before copying them into the readdir cache. Fixes: 69e34551152a ("fuse: allow caching readdir") Cc: stable@vger.kernel.org # v6.16+ Assisted-by: Bynario AI Signed-off-by: Samuel Page Reported-by: Qi Tang Reported-by: Zijun Hu Signed-off-by: Miklos Szeredi Link: https://patch.msgid.link/20260420090139.662772-1-mszeredi@redhat.com Signed-off-by: Christian Brauner Signed-off-by: Greg Kroah-Hartman

writeback: don't block sync for filesystems with no data integrity guarantees

2026-03-20T13:18:56Z

Add a SB_I_NO_DATA_INTEGRITY superblock flag for filesystems that cannot guarantee data persistence on sync (eg fuse). For superblocks with this flag set, sync kicks off writeback of dirty inodes but does not wait for the flusher threads to complete the writeback. This replaces the per-inode AS_NO_DATA_INTEGRITY mapping flag added in commit f9a49aa302a0 ("fs/writeback: skip AS_NO_DATA_INTEGRITY mappings in wait_sb_inodes()"). The flag belongs at the superblock level because data integrity is a filesystem-wide property, not a per-inode one. Having this flag at the superblock level also allows us to skip having to iterate every dirty inode in wait_sb_inodes() only to skip each inode individually. Prior to this commit, mappings with no data integrity guarantees skipped waiting on writeback completion but still waited on the flusher threads to finish initiating the writeback. Waiting on the flusher threads is unnecessary. This commit kicks off writeback but does not wait on the flusher threads. This change properly addresses a recent report [1] for a suspend-to-RAM hang seen on fuse-overlayfs that was caused by waiting on the flusher threads to finish: Workqueue: pm_fs_sync pm_fs_sync_work_fn Call Trace: __schedule+0x457/0x1720 schedule+0x27/0xd0 wb_wait_for_completion+0x97/0xe0 sync_inodes_sb+0xf8/0x2e0 __iterate_supers+0xdc/0x160 ksys_sync+0x43/0xb0 pm_fs_sync_work_fn+0x17/0xa0 process_one_work+0x193/0x350 worker_thread+0x1a1/0x310 kthread+0xfc/0x240 ret_from_fork+0x243/0x280 ret_from_fork_asm+0x1a/0x30 On fuse this is problematic because there are paths that may cause the flusher thread to block (eg if systemd freezes the user session cgroups first, which freezes the fuse daemon, before invoking the kernel suspend. The kernel suspend triggers ->write_node() which on fuse issues a synchronous setattr request, which cannot be processed since the daemon is frozen. Or if the daemon is buggy and cannot properly complete writeback, initiating writeback on a dirty folio already under writeback leads to writeback_get_folio() -> folio_prepare_writeback() -> unconditional wait on writeback to finish, which will cause a hang). This commit restores fuse to its prior behavior before tmp folios were removed, where sync was essentially a no-op. [1] https://lore.kernel.org/linux-fsdevel/CAJnrk1a-asuvfrbKXbEwwDSctvemF+6zfhdnuzO65Pt8HsFSRw@mail.gmail.com/T/#m632c4648e9cafc4239299887109ebd880ac6c5c1 Fixes: 0c58a97f919c ("fuse: remove tmp folio for writebacks and internal rb tree") Reported-by: John Cc: stable@vger.kernel.org Signed-off-by: Joanne Koong Link: https://patch.msgid.link/20260320005145.2483161-2-joannelkoong@gmail.com Reviewed-by: Jan Kara Reviewed-by: David Hildenbrand (Arm) Signed-off-by: Christian Brauner

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51Z

This was done entirely with mindless brute force, using git grep -l '\

Merge tag 'kmalloc_obj-treewide-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2026-02-21T19:02:58Z

Pull kmalloc_obj conversion from Kees Cook: "This does the tree-wide conversion to kmalloc_obj() and friends using coccinelle, with a subsequent small manual cleanup of whitespace alignment that coccinelle does not handle. This uncovered a clang bug in __builtin_counted_by_ref(), so the conversion is preceded by disabling that for current versions of clang. The imminent clang 22.1 release has the fix. I've done allmodconfig build tests for x86_64, arm64, i386, and arm. I did defconfig builds for alpha, m68k, mips, parisc, powerpc, riscv, s390, sparc, sh, arc, csky, xtensa, hexagon, and openrisc" * tag 'kmalloc_obj-treewide-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: kmalloc_obj: Clean up after treewide replacements treewide: Replace kmalloc with kmalloc_obj for non-scalar types compiler_types: Disable __builtin_counted_by_ref for Clang

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28Z

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

io_uring: Add size check for sqe->cmd

2026-02-19T14:26:26Z

For SQE128, sqe->cmd provides 80 bytes for uring_cmd. Add macro to check if size of user struct does not exceed 80 bytes at compile time. User doesn't have to track this manually during development. Replace io_uring_sqe_cmd() inline func with macro and add io_uring_sqe128_cmd() which checks struct size for 16 bytes cmd and 80 bytes cmd respectively. Signed-off-by: Govindarajulu Varadarajan Reviewed-by: Caleb Sander Mateos Signed-off-by: Jens Axboe