kernel/linux.git/fs/nfs/flexfilelayout, branch v7.2-rc2

NFSv4/flexfiles: honor FF_FLAGS_NO_IO_THRU_MDS in pg_get_mirror_count_write

2026-06-08T16:06:41+00:00

The FF_FLAGS_NO_IO_THRU_MDS flag lives on each lseg, so any fallback decision made when there is no current lseg (e.g. between LAYOUTRETURN and the next LAYOUTGET) cannot run the per-lseg check. Introduce a sticky hdr-level ditto for FF_FLAGS_NO_IO_THRU_MDS in struct nfs4_flexfile_layout::flags (NFS4_FF_HDR_NO_IO_THRU_MDS bit), set whenever ff_layout_alloc_lseg() parses an lseg with the flag. The bit is never cleared for the lifetime of the layout hdr; the server is assumed to be consistent in its no-fallback policy per file. kzalloc() in ff_layout_alloc_layout_hdr() zero-initializes the field. Use the new ff_layout_hdr_no_fallback_to_mds() helper to gate ff_layout_pg_get_mirror_count_write(): when pnfs_update_layout() returns NULL (e.g. NFS_LAYOUT_BULK_RECALL, pnfs_layout_io_test_failed, pnfs_layoutgets_blocked) the existing code unconditionally calls nfs_pageio_reset_write_mds(). This is a source of unwanted WRITE to MDS. Fix it by checking NFS4_FF_HDR_NO_IO_THRU_MDS bit, and if set surface -EAGAIN instead; the writepage-side caller (nfs_do_writepage() for buffered, nfs_direct_write_reschedule() for O_DIRECT) then redirties the request so writeback retries via pNFS. Fixes: 260074cd8413 ("pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS") Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Mike Snitzer Signed-off-by: Anna Schumaker

NFSv4/flexfiles: honor FF_FLAGS_NO_IO_THRU_MDS on fatal DS connect errors

2026-06-08T16:06:41+00:00

Commit f06bedfa62d5 ("pNFS/flexfiles: don't attempt pnfs on fatal DS errors") teaches ff_layout_{read,write}_pagelist() to return PNFS_NOT_ATTEMPTED when nfs4_ff_layout_prepare_ds() fails with a nfs_error_is_fatal() errno (e.g. -ETIMEDOUT from a SOFTCONN connect deadline, -ENOMEM, -ERESTARTSYS), so that the client gives up instead of spinning. pnfs_do_{read,write}() then dispatches the I/O through pnfs_{read,write}_through_mds() → nfs_pageio_reset_{read,write}_mds(). That fallback is unconditional and silently violates FF_FLAGS_NO_IO_THRU_MDS: when the layout segment carries the flag (typically single-mirror appliance layouts where MDS I/O is explicitly forbidden), the out_failed: path's \`&& !ds_fatal_error\` clause overrides the flag's short-circuit through ff_layout_avoid_mds_available_ds() and routes the I/O to the MDS file handle anyway. This is reachable in practice during a data-server restart: SOFTCONN exhaustion produces -ETIMEDOUT, which is fatal per nfs_error_is_fatal(), which triggers PNFS_NOT_ATTEMPTED, which silently goes to MDS. Preserve the upstream "don't spin on fatal errors" intent for layouts that permit MDS fallback. For layouts with FF_FLAGS_NO_IO_THRU_MDS set, mark the layout for return and request PNFS_TRY_AGAIN instead; if the server cannot supply a usable layout the failure now surfaces cleanly via pnfs_update_layout(), rather than via silent MDS I/O that contradicts the flag. Fixes: f06bedfa62d5 ("pNFS/flexfiles: don't attempt pnfs on fatal DS errors") Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Mike Snitzer Signed-off-by: Anna Schumaker

NFSv4/flexfiles: reject zero filehandle version count

2026-06-08T14:21:55+00:00

ff_layout_alloc_lseg() decodes the filehandle-version array count from the flexfiles layout body. The value is used as the count for kzalloc_objs(), and the current code only rejects NULL. A zero count yields ZERO_SIZE_PTR, which can be stored in dss_info->fh_versions even though later flexfiles paths assume that at least one filehandle version exists. Reject fh_count == 0 before the allocation, matching the existing zero version_count validation in the flexfiles GETDEVICEINFO parser. A QEMU/KASAN run with a malformed flexfiles layout hit: KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] RIP: 0010:ff_layout_encode_ff_layoutupdate.isra.0+0x15f/0x750 ff_layout_encode_layoutreturn+0x683/0x970 nfs4_xdr_enc_layoutreturn+0x278/0x3a0 Kernel panic - not syncing: Fatal exception The patched kernel rejects the malformed layout without KASAN/oops/panic, and a valid fh_count=1 regression still opens, reads, and unmounts cleanly. Cc: stable@vger.kernel.org Fixes: d67ae825a59d ("pnfs/flexfiles: Add the FlexFile Layout Driver") Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito Signed-off-by: Anna Schumaker

nfs: replace NFS_FILEID() and nfsi->fileid with inode->i_ino

2026-06-08T14:21:54+00:00

Now that inode->i_ino stores the full 64-bit NFS fileid, replace all uses of NFS_FILEID(), set_nfs_fileid(), and direct nfsi->fileid accesses with inode->i_ino throughout the NFS client. Remove the NFS_FILEID() and set_nfs_fileid() helper functions from include/linux/nfs_fs.h since they are no longer needed. Also fix two pre-existing truncation bugs in nfs4trace.h where fileid trace fields were declared as u32 instead of u64. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Jeff Layton Signed-off-by: Anna Schumaker

Merge tag 'nfs-for-7.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2026-04-24T21:20:03+00:00

Pull NFS client updates from Trond Myklebust: "Bugfixes: - Fix handling of ENOSPC so that if we have to resend writes, they are written synchronously - SUNRPC RDMA transport fixes from Chuck - Several fixes for delegated timestamps in NFSv4.2 - Failure to obtain a directory delegation should not cause stat() to fail with NFSv4 - Rename was failing to update timestamps when a directory delegation is held on NFSv4 - Ensure we check rsize/wsize after crossing a NFSv4 filesystem boundary - NFSv4/pnfs: - If the server is down, retry the layout returns on reboot - Fallback to MDS could result in a short write being incorrectly logged Cleanups: - Use memcpy_and_pad in decode_fh" * tag 'nfs-for-7.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (21 commits) NFS: Fix RCU dereference of cl_xprt in nfs_compare_super_address NFS: remove redundant __private attribute from nfs_page_class NFSv4.2: fix CLONE/COPY attrs in presence of delegated attributes NFS: fix writeback in presence of errors nfs: use memcpy_and_pad in decode_fh NFSv4.1: Apply session size limits on clone path NFSv4: retry GETATTR if GET_DIR_DELEGATION failed NFS: fix RENAME attr in presence of directory delegations pnfs/flexfiles: validate ds_versions_cnt is non-zero NFS/blocklayout: print each device used for SCSI layouts xprtrdma: Post receive buffers after RPC completion xprtrdma: Scale receive batch size with credit window xprtrdma: Replace rpcrdma_mr_seg with xdr_buf cursor xprtrdma: Decouple frwr_wp_create from frwr_map xprtrdma: Close lost-wakeup race in xprt_rdma_alloc_slot xprtrdma: Avoid 250 ms delay on backlog wakeup xprtrdma: Close sendctx get/put race that can block a transport nfs: update inode ctime after removexattr operation nfs: fix utimensat() for atime with delegated timestamps NFS: improve "Server wrote zero bytes" error ...

pnfs/flexfiles: validate ds_versions_cnt is non-zero

2026-04-13T21:04:16+00:00

nfs4_ff_alloc_deviceid_node() reads version_count from XDR without checking it is non-zero. When a malicious NFS server sends a pNFS LAYOUTGET response with version_count=0, kcalloc(0, ...) returns ZERO_SIZE_PTR (0x10). The subsequent ds_versions[0] access in nfs4_ff_layout_ds_version() and other callers dereferences this invalid pointer, causing an out-of-bounds read. Add a check for version_count == 0 after parsing it from XDR, before the allocation. The OOB read was confirmed with KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] from accessing ZERO_SIZE_PTR. Fixes: d67ae825a59d ("pnfs/flexfiles: Add the FlexFile Layout Driver") Reported-by: Klaudia Kloc Reported-by: Dawid Moczadło Tested-by: Jenny Guanni Qu Signed-off-by: Jenny Guanni Qu Signed-off-by: Trond Myklebust

treewide: change inode->i_ino from unsigned long to u64

2026-03-06T13:31:28+00:00

On 32-bit architectures, unsigned long is only 32 bits wide, which causes 64-bit inode numbers to be silently truncated. Several filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that exceed 32 bits, and this truncation can lead to inode number collisions and other subtle bugs on 32-bit systems. Change the type of inode->i_ino from unsigned long to u64 to ensure that inode numbers are always represented as 64-bit values regardless of architecture. Update all format specifiers treewide from %lu/%lx to %llu/%llx to match the new type, along with corresponding local variable types. This is the bulk treewide conversion. Earlier patches in this series handled trace events separately to allow trace field reordering for better struct packing on 32-bit. Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org Acked-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Chuck Lever Signed-off-by: Christian Brauner

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

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

pnfs/flexfiles: Fix memory leak in nfs4_ff_alloc_deviceid_node()

2026-01-05T04:03:25+00:00

In nfs4_ff_alloc_deviceid_node(), if the allocation for ds_versions fails, the function jumps to the out_scratch label without freeing the already allocated dsaddrs list, leading to a memory leak. Fix this by jumping to the out_err_drain_dsaddrs label, which properly frees the dsaddrs list before cleaning up other resources. Fixes: d67ae825a59d6 ("pnfs/flexfiles: Add the FlexFile Layout Driver") Signed-off-by: Zilin Guan Signed-off-by: Trond Myklebust

NFSv4/flexfiles: fix to allocate mirror->dss before use

2025-10-13T18:33:00+00:00

Move mirror_array's dss_count initialization and dss allocation to ff_layout_alloc_mirror(), just before the loop that initializes each nfs4_ff_layout_ds_stripe's nfs_file_localio. Also handle NULL return from kcalloc() and remove one level of indent in ff_layout_alloc_mirror(). This commit fixes dangling nfsd_serv refcount issues seen when using NFS LOCALIO and then attempting to stop the NFSD service. Fixes: 20b1d75fb840 ("NFSv4/flexfiles: Add support for striped layouts") Signed-off-by: Mike Snitzer Signed-off-by: Anna Schumaker