kernel.git/fs/nfs, branch linux-6.15.y

pNFS: Fix uninited ptr deref in block/scsi layout

2025-08-20T16:36:26Z

[ Upstream commit 9768797c219326699778fba9cd3b607b2f1e7950 ] The error occurs on the third attempt to encode extents. When function ext_tree_prepare_commit() reallocates a larger buffer to retry encoding extents, the "layoutupdate_pages" page array is initialized only after the retry loop. But ext_tree_free_commitdata() is called on every iteration and tries to put pages in the array, thus dereferencing uninitialized pointers. An additional problem is that there is no limit on the maximum possible buffer_size. When there are too many extents, the client may create a layoutcommit that is larger than the maximum possible RPC size accepted by the server. During testing, we observed two typical scenarios. First, one memory page for extents is enough when we work with small files, append data to the end of the file, or preallocate extents before writing. But when we fill a new large file without preallocating, the number of extents can be huge, and counting the number of written extents in ext_tree_encode_commit() does not help much. Since this number increases even more between unlocking and locking of ext_tree, the reallocated buffer may not be large enough again and again. Co-developed-by: Konstantin Evtushenko Signed-off-by: Konstantin Evtushenko Signed-off-by: Sergey Bashirov Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250630183537.196479-2-sergeybashirov@gmail.com Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

pNFS: Handle RPC size limit for layoutcommits

2025-08-20T16:36:26Z

[ Upstream commit d897d81671bc4615c80f4f3bd5e6b218f59df50c ] When there are too many block extents for a layoutcommit, they may not all fit into the maximum-sized RPC. This patch allows the generic pnfs code to properly handle -ENOSPC returned by the block/scsi layout driver and trigger additional layoutcommits if necessary. Co-developed-by: Konstantin Evtushenko Signed-off-by: Konstantin Evtushenko Signed-off-by: Sergey Bashirov Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250630183537.196479-5-sergeybashirov@gmail.com Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

pNFS: Fix disk addr range check in block/scsi layout

2025-08-20T16:36:26Z

[ Upstream commit 7db6e66663681abda54f81d5916db3a3b8b1a13d ] At the end of the isect translation, disc_addr represents the physical disk offset. Thus, end calculated from disk_addr is also a physical disk offset. Therefore, range checking should be done using map->disk_offset, not map->start. Signed-off-by: Sergey Bashirov Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250702133226.212537-1-sergeybashirov@gmail.com Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

pNFS: Fix stripe mapping in block/scsi layout

2025-08-20T16:36:26Z

[ Upstream commit 81438498a285759f31e843ac4800f82a5ce6521f ] Because of integer division, we need to carefully calculate the disk offset. Consider the example below for a stripe of 6 volumes, a chunk size of 4096, and an offset of 70000. chunk = div_u64(offset, dev->chunk_size) = 70000 / 4096 = 17 offset = chunk * dev->chunk_size = 17 * 4096 = 69632 disk_offset_wrong = div_u64(offset, dev->nr_children) = 69632 / 6 = 11605 disk_chunk = div_u64(chunk, dev->nr_children) = 17 / 6 = 2 disk_offset = disk_chunk * dev->chunk_size = 2 * 4096 = 8192 Signed-off-by: Sergey Bashirov Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250701122341.199112-1-sergeybashirov@gmail.com Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

NFS: Fix the setting of capabilities when automounting a new filesystem

2025-08-20T16:35:44Z

commit b01f21cacde9f2878492cf318fee61bf4ccad323 upstream. Capabilities cannot be inherited when we cross into a new filesystem. They need to be reset to the minimal defaults, and then probed for again. Fixes: 54ceac451598 ("NFS: Share NFS superblocks per-protocol per-server per-FSID") Cc: stable@vger.kernel.org Reviewed-by: Benjamin Coddington Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

NFS: Fixup allocation flags for nfsiod's __GFP_NORETRY

2025-08-15T10:16:57Z

[ Upstream commit 99765233ab42bf7a4950377ad7894dce8a5c0e60 ] If the NFS client is doing writeback from a workqueue context, avoid using __GFP_NORETRY for allocations if the task has set PF_MEMALLOC_NOIO or PF_MEMALLOC_NOFS. The combination of these flags makes memory allocation failures much more likely. We've seen those allocation failures show up when the loopback driver is doing writeback from a workqueue to a file on NFS, where memory allocation failure results in errors or corruption within the loopback device's filesystem. Suggested-by: Trond Myklebust Fixes: 0bae835b63c5 ("NFS: Avoid writeback threads getting stuck in mempool_alloc()") Signed-off-by: Benjamin Coddington Reviewed-by: Laurence Oberman Tested-by: Laurence Oberman Reviewed-by: Jeff Layton Link: https://lore.kernel.org/r/f83ac1155a4bc670f2663959a7a068571e06afd9.1752111622.git.bcodding@redhat.com Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

NFSv4.2: another fix for listxattr

2025-08-15T10:16:57Z

[ Upstream commit 9acb237deff7667b0f6b10fe6b1b70c4429ea049 ] Currently, when the server supports NFS4.1 security labels then security.selinux label in included twice. Instead, only add it when the server doesn't possess security label support. Fixes: 243fea134633 ("NFSv4.2: fix listxattr to return selinux security label") Signed-off-by: Olga Kornievskaia Link: https://lore.kernel.org/r/20250722205641.79394-1-okorniev@redhat.com Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

NFS: Fix filehandle bounds checking in nfs_fh_to_dentry()

2025-08-15T10:16:57Z

[ Upstream commit ef93a685e01a281b5e2a25ce4e3428cf9371a205 ] The function needs to check the minimal filehandle length before it can access the embedded filehandle. Reported-by: zhangjian Fixes: 20fa19027286 ("nfs: add export operations") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

NFS: Fix wakeup of __nfs_lookup_revalidate() in unblock_revalidate()

2025-08-15T10:16:57Z

[ Upstream commit 1db3a48e83bb64a70bf27263b7002585574a9c2d ] Use store_release_wake_up() to add the appropriate memory barrier before calling wake_up_var(&dentry->d_fsdata). Reported-by: Lukáš Hejtmánek Suggested-by: Santosh Pradhan Link: https://lore.kernel.org/all/18945D18-3EDB-4771-B019-0335CE671077@ics.muni.cz/ Fixes: 99bc9f2eb3f7 ("NFS: add barriers when testing for NFS_FSDATA_BLOCKED") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

pNFS/flexfiles: don't attempt pnfs on fatal DS errors

2025-08-15T10:16:57Z

[ Upstream commit f06bedfa62d57f7b67d44aacd6badad2e13a803f ] When an applications get killed (SIGTERM/SIGINT) while pNFS client performs a connection to DS, client ends in an infinite loop of connect-disconnect. This source of the issue, it that flexfilelayoutdev#nfs4_ff_layout_prepare_ds gets an error on nfs4_pnfs_ds_connect with status ERESTARTSYS, which is set by rpc_signal_task, but the error is treated as transient, thus retried. The issue is reproducible with Ctrl+C the following script(there should be ~1000 files in a directory, client should must not have any connections to DSes): ``` echo 3 > /proc/sys/vm/drop_caches for i in * do head -1 $i done ``` The change aims to propagate the nfs4_ff_layout_prepare_ds error state to the caller that can decide whatever this is a retryable error or not. Signed-off-by: Tigran Mkrtchyan Link: https://lore.kernel.org/r/20250627071751.189663-1-tigran.mkrtchyan@desy.de Fixes: 260f32adb88d ("pNFS/flexfiles: Check the result of nfs4_pnfs_ds_connect") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin