kernel/linux.git/fs/nfs, branch v6.6.144

NFS: Prevent resource leak in nfs_alloc_server()

2026-07-04T11:42:27+00:00

commit d189f224308c8ac3feeea8e442c99922bd18f1b2 upstream. It was overlooked to call ida_free() after a failed nfs_alloc_iostats() call. Thus add the missed function call in an if branch. Fixes: 1c7251187dc067a6d460cf33ca67da9c1dd87807 ("NFS: add superblock sysfs entries") Cc: stable@vger.kernel.org Reported-by: Christophe Jaillet Closes: https://lore.kernel.org/linux-nfs/1c8e10c9-def7-4f0d-8aa1-23c8035a38c8@wanadoo.fr/ Signed-off-by: Markus Elfring Signed-off-by: Anna Schumaker Signed-off-by: Greg Kroah-Hartman

NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr

2026-07-04T11:42:27+00:00

commit 41fe0f7b84f0cb822ae10ab08592996a592b2a25 upstream. nfs4_decode_mp_ds_addr() decodes the r_netid and r_addr opaques of a netaddr4 from a GETDEVICEINFO multipath-DS body, then immediately calls strrchr(buf, '.') to locate the port separator. Both decodes use xdr_stream_decode_string_dup(), and the current code checks only "nlen < 0" / "rlen < 0" before dereferencing the returned string. When the on-wire opaque has length zero, xdr_stream_decode_opaque_inline() returns 0 and xdr_stream_decode_string_dup() falls through to its "*str = NULL; return ret" tail, leaving buf NULL with a return value of 0. The "< 0" check does not catch this, and the next line is strrchr(NULL, '.'), a kernel NULL pointer dereference reachable from any pNFS-flexfile client mounted against a malicious or compromised metadata server. Reject the zero-length cases explicitly so the decoder fails with -EBADMSG (treated as a malformed GETDEVICEINFO body) instead of panicking the client. Cc: stable@vger.kernel.org Fixes: 6b7f3cf96364 ("nfs41: pull decode_ds_addr from file layout to generic pnfs") Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito Signed-off-by: Anna Schumaker Signed-off-by: Greg Kroah-Hartman

pNFS: Fix use-after-free in pnfs_update_layout()

2026-07-04T11:42:26+00:00

commit 13e198a90ca4050f4bee8a3f23680389a6563ccc upstream. When hitting the NFS_LAYOUT_RETURN branch in pnfs_update_layout(), the code calls pnfs_prepare_to_retry_layoutget(lo). If it succeeds, pnfs_put_layout_hdr(lo) is called before trace_pnfs_update_layout(), which still references 'lo'. This results in a use-after-free when the tracepoint accesses lo's fields. Fix this by moving the tracepoint call before pnfs_put_layout_hdr(lo). Fixes: 2c8d5fc37fe2 ("pNFS: Stricter ordering of layoutget and layoutreturn") Cc: stable@vger.kernel.org Signed-off-by: Wentao Liang Signed-off-by: Anna Schumaker Signed-off-by: Greg Kroah-Hartman

nfs/blocklayout: Fix compilation error (`make W=1`) in bl_write_pagelist()

2026-05-23T11:03:21+00:00

[ Upstream commit f83c8dda456ce4863f346aa26d88efa276eda35d ] Clang compiler is not happy about set but unused variable (when dprintk() is no-op): .../blocklayout/blocklayout.c:384:9: error: variable 'count' set but not used [-Werror,-Wunused-but-set-variable] Remove a leftover from the previous cleanup. Fixes: 3a6fd1f004fc ("pnfs/blocklayout: remove read-modify-write handling in bl_write_pagelist") Acked-by: Anna Schumaker Reviewed-by: Jeff Layton Signed-off-by: Andy Shevchenko Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

pNFS: Fix a deadlock when returning a delegation during open()

2026-03-25T10:05:59+00:00

[ Upstream commit 857bf9056291a16785ae3be1d291026b2437fc48 ] Ben Coddington reports seeing a hang in the following stack trace: 0 [ffffd0b50e1774e0] __schedule at ffffffff9ca05415 1 [ffffd0b50e177548] schedule at ffffffff9ca05717 2 [ffffd0b50e177558] bit_wait at ffffffff9ca061e1 3 [ffffd0b50e177568] __wait_on_bit at ffffffff9ca05cfb 4 [ffffd0b50e1775c8] out_of_line_wait_on_bit at ffffffff9ca05ea5 5 [ffffd0b50e177618] pnfs_roc at ffffffffc154207b [nfsv4] 6 [ffffd0b50e1776b8] _nfs4_proc_delegreturn at ffffffffc1506586 [nfsv4] 7 [ffffd0b50e177788] nfs4_proc_delegreturn at ffffffffc1507480 [nfsv4] 8 [ffffd0b50e1777f8] nfs_do_return_delegation at ffffffffc1523e41 [nfsv4] 9 [ffffd0b50e177838] nfs_inode_set_delegation at ffffffffc1524a75 [nfsv4] 10 [ffffd0b50e177888] nfs4_process_delegation at ffffffffc14f41dd [nfsv4] 11 [ffffd0b50e1778a0] _nfs4_opendata_to_nfs4_state at ffffffffc1503edf [nfsv4] 12 [ffffd0b50e1778c0] _nfs4_open_and_get_state at ffffffffc1504e56 [nfsv4] 13 [ffffd0b50e177978] _nfs4_do_open at ffffffffc15051b8 [nfsv4] 14 [ffffd0b50e1779f8] nfs4_do_open at ffffffffc150559c [nfsv4] 15 [ffffd0b50e177a80] nfs4_atomic_open at ffffffffc15057fb [nfsv4] 16 [ffffd0b50e177ad0] nfs4_file_open at ffffffffc15219be [nfsv4] 17 [ffffd0b50e177b78] do_dentry_open at ffffffff9c09e6ea 18 [ffffd0b50e177ba8] vfs_open at ffffffff9c0a082e 19 [ffffd0b50e177bd0] dentry_open at ffffffff9c0a0935 The issue is that the delegreturn is being asked to wait for a layout return that cannot complete because a state recovery was initiated. The state recovery cannot complete until the open() finishes processing the delegations it was given. The solution is to propagate the existing flags that indicate a non-blocking call to the function pnfs_roc(), so that it knows not to wait in this situation. Reported-by: Benjamin Coddington Fixes: 29ade5db1293 ("pNFS: Wait on outstanding layoutreturns to complete in pnfs_roc()") Signed-off-by: Trond Myklebust [ Minor conflict resolved. ] Signed-off-by: Li hongliang <1468888505@139.com> Signed-off-by: Greg Kroah-Hartman

NFS: Fix a deadlock involving nfs_release_folio()

2026-03-25T10:05:59+00:00

[ Upstream commit cce0be6eb4971456b703aaeafd571650d314bcca ] Wang Zhaolong reports a deadlock involving NFSv4.1 state recovery waiting on kthreadd, which is attempting to reclaim memory by calling nfs_release_folio(). The latter cannot make progress due to state recovery being needed. It seems that the only safe thing to do here is to kick off a writeback of the folio, without waiting for completion, or else kicking off an asynchronous commit. Reported-by: Wang Zhaolong Fixes: 96780ca55e3c ("NFS: fix up nfs_release_folio() to try to release the page") Signed-off-by: Trond Myklebust [ Minor conflict resolved. ] Signed-off-by: Li hongliang <1468888505@139.com> Signed-off-by: Greg Kroah-Hartman

nfs: pass explicit offset/count to trace events

2026-03-25T10:05:59+00:00

[ Upstream commit fada32ed6dbc748f447c8d050a961b75d946055a ] nfs_folio_length is unsafe to use without having the folio locked and a check for a NULL ->f_mapping that protects against truncations and can lead to kernel crashes. E.g. when running xfstests generic/065 with all nfs trace points enabled. Follow the model of the XFS trace points and pass in an explіcit offset and length. This has the additional benefit that these values can be more accurate as some of the users touch partial folio ranges. Fixes: eb5654b3b89d ("NFS: Enable tracing of nfs_invalidate_folio() and nfs_launder_folio()") Reported-by: Chuck Lever Signed-off-by: Christoph Hellwig Signed-off-by: Anna Schumaker [ Minor conflict resolved. ] Signed-off-by: Li hongliang <1468888505@139.com> Signed-off-by: Greg Kroah-Hartman

fs/nfs: Fix readdir slow-start regression

2026-03-04T12:20:04+00:00

[ Upstream commit 42e7c876b182da65723700f6bc507a8aecb10d3b ] Commit 580f236737d1 ("NFS: Adjust the amount of readahead performed by NFS readdir") reduces the amount of readahead names caching done by the client. The downside of this approach is READDIR now may suffer from a slow-start issue, where initially it will fetch names that fit in a single page, then in 2, 4, 8 until the maximum supported transfer size (usually 1M). This patch tries to take a balanced approach between mitigating the slow-start issue still maintaining some efficiency gains. Fixes: 580f236737d1 ("NFS: Adjust the amount of readahead performed by NFS readdir") Signed-off-by: Sagi Grimberg Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin

pNFS: fix a missing wake up while waiting on NFS_LAYOUT_DRAIN

2026-03-04T12:20:03+00:00

[ Upstream commit 5248d8474e594d156bee1ed10339cc16e207a28b ] It is possible to have a task get stuck on waiting on the NFS_LAYOUT_DRAIN in the following scenario 1. cpu a: waiter test NFS_LAYOUT_DRAIN (1) and plh_outstanding (1) 2. cpu b: atomic_dec_and_test() -> clear bit -> wake up 3. cpu c: sets NFS_LAYOUT_DRAIN again 4. cpu a: calls wait_on_bit() sleeps forever. To expand on this we have say 2 outstanding pnfs write IO that get ESTALE which causes both to call pnfs_destroy_layout() and set the NFS_LAYOUT_DRAIN bit but the 1st one doesn't call the pnfs_put_layout_hdr() yet (as that would prevent the 2nd ESTALE write from trying to call pnfs_destroy_layout()). If the 1st ESTALE write is the one that initially sets the NFS_LAYOUT_DRAIN so that new IO on this file initiates new LAYOUTGET. Another new write would find NFS_LAYOUT_DRAIN set and phl_outstanding>0 (step 1) and would wait_on_bit(). LAYOUTGET completes doing step 2. Now, the 2nd of ESTALE writes is calling pnfs_destory_layout() and set the NFS_LAYOUT_DRAIN bit (step 3). Finally, the waiting write wakes up to check the bit and goes back to sleep. The problem revolves around the fact that if NFS_LAYOUT_INVALID_STID was already set, it should not do the work of pnfs_mark_layout_stateid_invalid(), thus NFS_LAYOUT_DRAIN will not be set more than once for an invalid layout. Suggested-by: Trond Myklebust Fixes: 880265c77ac4 ("pNFS: Avoid a live lock condition in pnfs_update_layout()") Signed-off-by: Olga Kornievskaia Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin

pnfs/flexfiles: Fix memory leak in nfs4_ff_alloc_deviceid_node()

2026-01-30T09:27:22+00:00

[ Upstream commit 0c728083654f0066f5e10a1d2b0bd0907af19a58 ] 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 Signed-off-by: Sasha Levin