kernel/linux.git/fs, branch v6.1.175

cifs: Fix busy dentry used after unmounting

2026-06-01T15:39:36+00:00

commit c68337442f03953237a94577beb468ab2662a851 upstream. Since commit 340cea84f691c ("cifs: open files should not hold ref on superblock"), cifs file only holds the dentry ref_cnt, the cifs file close work(cfile->deferred) could be executed after unmounting, which will trigger a warning in generic_shutdown_super: BUG: Dentry 00000000a14a6845{i=c,n=file} still in use (1) [unmount of cifs cifs] The detailed processs is: process A process B kworker fd = open(PATH) vfs_open file->__f_path = *path // dentry->d_lockref.count = 1 cifs_open cifs_new_fileinfo cfile->dentry = dget(dentry) // dentry->d_lockref.count = 2 close(fd) __fput cifs_close queue_delayed_work(deferredclose_wq, cfile->deferred) dput(dentry) // dentry->d_lockref.count = 1 smb2_deferred_work_close _cifsFileInfo_put list_del(&cifs_file->flist) umount cleanup_mnt deactivate_super cifs_kill_sb cifs_close_all_deferred_files_sb cifs_close_all_deferred_files // cannot find cfile, skip _cifsFileInfo_put kill_anon_super generic_shutdown_super shrink_dcache_for_umount umount_check WARN ! // dentry->d_lockref.count = 1 cifsFileInfo_put_final dput(cifs_file->dentry) // dentry->d_lockref.count = 0 Fix it by flushing 'deferredclose_wq' before calling kill_anon_super. Fetch a reproducer in https://bugzilla.kernel.org/show_bug.cgi?id=221548. Fixes: 340cea84f691c ("cifs: open files should not hold ref on superblock") Cc: stable@vger.kernel.org Reviewed-by: Shyam Prasad N Signed-off-by: Zhihao Cheng Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

sysfs: don't remove existing directory on update failure

2026-06-01T15:39:34+00:00

commit 237557b8a81ab948e8332f7c0058e758f081c0a3 upstream. When sysfs_update_group() is called for a named group and create_files() fails (e.g. -ENOMEM), internal_create_group() calls kernfs_remove(kn) on the group directory. In the update path, kn was obtained via kernfs_find_and_get() and refers to a directory that already existed before this call. Removing it silently destroys a sysfs group that the caller did not create. Only remove the directory if we created it ourselves. On update failure the directory remains as it is left empty by remove_files() inside create_files(), but can be repopulated by a retry. Cc: Rajat Jain Fixes: c855cf2759d2 ("sysfs: Fix internal_create_group() for named group updates") Cc: stable Assisted-by: gkh_clanker_t1000 Reviewed-by: Rafael J. Wysocki (Intel) Reviewed-by: Danilo Krummrich Link: https://patch.msgid.link/2026052003-uniquely-hastily-c093@gregkh Signed-off-by: Greg Kroah-Hartman

smb: client: reject userspace cifs.spnego descriptions

2026-06-01T15:39:34+00:00

commit 3da1fdf4efbc490041eb4f836bf596201203f8f2 upstream. cifs.spnego key descriptions contain authority-bearing fields such as pid, uid, creduid, and upcall_target that cifs.upcall treats as kernel-originating inputs. However, userspace can also create keys of this type through request_key(2) or add_key(2), allowing those fields to be supplied without CIFS origin. Only accept cifs.spnego descriptions while CIFS is using its private spnego_cred to request the key. Fixes: f1d662a7d5e5 ("[CIFS] Add upcall files for cifs to use spnego/kerberos") Assisted-by: avom-custom-harness:gpt-5.5-qwen3.6-mod-mix Reviewed-by: David Howells Signed-off-by: Asim Viladi Oglu Manizada Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

ceph: fix a buffer leak in __ceph_setxattr()

2026-06-01T15:39:32+00:00

commit 5d3cc36b4e77a27ce7b686b7c59c7072bcb3fa8e upstream. The old_blob in __ceph_setxattr() can store ci->i_xattrs.prealloc_blob value during the retry. However, it is never called the ceph_buffer_put() for the old_blob object. This patch fixes the issue of the buffer leak. Cc: stable@vger.kernel.org Signed-off-by: Viacheslav Dubeyko Reviewed-by: Alex Markuze Signed-off-by: Ilya Dryomov Signed-off-by: Greg Kroah-Hartman

smb/client: fix possible infinite loop and oob read in symlink_data()

2026-06-01T15:39:32+00:00

commit 7d9a7f1f96cd617ee9e75bb22217c709038e26b8 upstream. On 32-bit architectures, the infinite loop is as follows: len = p->ErrorDataLength == 0xfffffff8 u8 *next = p->ErrorContextData + len next == p On 32-bit architectures, the out-of-bounds read is as follows: len = p->ErrorDataLength == 0xfffffff0 u8 *next = p->ErrorContextData + len next == (u8 *)p - 8 Reported-by: ChenXiaoSong Fixes: 76894f3e2f71 ("cifs: improve symlink handling for smb2+") Cc: stable@vger.kernel.org Signed-off-by: Ye Bin Reviewed-by: ChenXiaoSong Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

smb: client: fix OOB reads parsing symlink error response

2026-06-01T15:39:31+00:00

[ Upstream commit 3df690bba28edec865cf7190be10708ad0ddd67e ] When a CREATE returns STATUS_STOPPED_ON_SYMLINK, smb2_check_message() returns success without any length validation, leaving the symlink parsers as the only defense against an untrusted server. symlink_data() walks SMB 3.1.1 error contexts with the loop test "p < end", but reads p->ErrorId at offset 4 and p->ErrorDataLength at offset 0. When the server-controlled ErrorDataLength advances p to within 1-7 bytes of end, the next iteration will read past it. When the matching context is found, sym->SymLinkErrorTag is read at offset 4 from p->ErrorContextData with no check that the symlink header itself fits. smb2_parse_symlink_response() then bounds-checks the substitute name using SMB2_SYMLINK_STRUCT_SIZE as the offset of PathBuffer from iov_base. That value is computed as sizeof(smb2_err_rsp) + sizeof(smb2_symlink_err_rsp), which is correct only when ErrorContextCount == 0. With at least one error context the symlink data sits 8 bytes deeper, and each skipped non-matching context shifts it further by 8 + ALIGN(ErrorDataLength, 8). The check is too short, allowing the substitute name read to run past iov_len. The out-of-bound heap bytes are UTF-16-decoded into the symlink target and returned to userspace via readlink(2). Fix this all up by making the loops test require the full context header to fit, rejecting sym if its header runs past end, and bound the substitute name against the actual position of sym->PathBuffer rather than a fixed offset. Because sub_offs and sub_len are 16bits, the pointer math will not overflow here with the new greater-than. Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: Bharath SM Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Cc: stable Reviewed-by: Paulo Alcantara (Red Hat) Assisted-by: gregkh_clanker_t1000 Signed-off-by: Greg Kroah-Hartman Signed-off-by: Steve French Signed-off-by: Alva Lan Signed-off-by: Sasha Levin

smb: client: correctly handle ErrorContextData as a flexible array

2026-06-01T15:39:30+00:00

[ Upstream commit 215b7f9ecb8d7c14d56febdcdd246f3579c32aba ] The `smb2_symlink_err_rsp` structure was previously defined with `ErrorContextData` as a single `__u8` byte. However, the `ErrorContextData` field is intended to be a variable-length array based on `ErrorDataLength`. This mismatch leads to incorrect pointer arithmetic and potential memory access issues when processing error contexts. Updates the `ErrorContextData` field to be a flexible array (`__u8 ErrorContextData[]`). Additionally, it modifies the corresponding casts in the `symlink_data()` function to properly handle the flexible array, ensuring correct memory calculations and data handling. These changes improve the robustness of SMB2 symlink error processing. Signed-off-by: Liang Jie Suggested-by: Tom Talpey Signed-off-by: Steve French [ Remove the __counted_by_le annotation in v6.1. ] Signed-off-by: Alva Lan Signed-off-by: Sasha Levin

btrfs: fix double-decrement of bytes_may_use in submit_one_async_extent()

2026-06-01T15:39:26+00:00

[ Upstream commit 82323b1a7088b7a5c3e528a5d634bff447fa286f ] submit_one_async_extent() calls btrfs_reserve_extent(), which decrements bytes_may_use. If the call btrfs_create_io_em() fails, we jump to out_free_reserve, which calls extent_clear_unlock_delalloc(). Because we're specifying EXTENT_DO_ACCOUNTING, i.e. EXTENT_CLEAR_META_RESV | EXTENT_CLEAR_DATA_RESV, this decreases bytes_may_use again. This can lead to problems later on, as an initial write can fail only for the writeback to silently ENOSPC. Fix this by replacing EXTENT_DO_ACCOUNTING with EXTENT_CLEAR_META_RESV. This parallels a4fe134fc1d8eb ("btrfs: fix a double release on reserved extents in cow_one_range()"), which is the same fix in cow_one_range(). Fixes: 151a41bc46df ("Btrfs: fix what bits we clear when erroring out from delalloc") Reviewed-by: Qu Wenruo Signed-off-by: Mark Harmstone Signed-off-by: David Sterba Signed-off-by: Sasha Levin

fs/adfs: validate nzones in adfs_validate_bblk()

2026-06-01T15:39:26+00:00

[ Upstream commit dd9d3e16c2d5fa166e13dce07413be51f42c8f5d ] Reject ADFS disc records with a zero zone count during boot block validation, before the disc record is used. When nzones is 0, adfs_read_map() passes it to kmalloc_array(0, ...) which returns ZERO_SIZE_PTR, and adfs_map_layout() then writes to dm[-1], causing an out-of-bounds write before the allocated buffer. adfs_validate_dr0() already rejects nzones != 1 for old-format images. Add the equivalent check to adfs_validate_bblk() for new-format images so that a crafted image with nzones == 0 is rejected at probe time. Found by syzkaller. Fixes: f6f14a0d71b0 ("fs/adfs: map: move map-specific sb initialisation to map.c") Signed-off-by: Bae Yeonju Signed-off-by: Russell King (Oracle) Signed-off-by: Sasha Levin

ksmbd: scope conn->binding slowpath to bound sessions only

2026-06-01T15:39:25+00:00

[ Upstream commit b0da97c034b6107d14e537e212d4ce8b22109a58 ] When the binding SESSION_SETUP sets conn->binding = true, the flag stays set after the call so that the global session lookup in ksmbd_session_lookup_all() can find the session, which was not added to conn->sessions. Because the flag is connection-wide, the global lookup path will also resolve any other session by id if asked. Tighten the global lookup so that the returned session must have this connection registered in its channel xarray (sess->ksmbd_chann_list). The channel entry is installed by the existing binding_session path in ntlm_authenticate()/krb5_authenticate() when a SESSION_SETUP completes successfully, so this condition is a strict equivalent of "this connection has been accepted as a channel of this session". Connections that have not bound to a given session cannot reach it via the global table. The existing conn->binding gate for entering the slowpath is preserved so that non-binding connections keep the fast-path-only behavior, and the session->state check is unchanged. Fixes: f5a544e3bab7 ("ksmbd: add support for SMB3 multichannel") Signed-off-by: Hyunwoo Kim Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin