kernel/linux.git/fs, branch v6.19.11

ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

2026-04-02T11:25:57+00:00

[ Upstream commit 519b76ac0b31d86b45784735d4ef964e8efdc56b ] Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'mballoc.c'. To solve this issue, the ext4 test code needs to be decoupled. The ext4 test module is compiled into a separate module. Reported-by: ChenXiaoSong Closes: https://patchwork.kernel.org/project/cifs-client/patch/20260118091313.1988168-2-chenxiaosong.chenxiaosong@linux.dev/ Fixes: 7c9fa399a369 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc") Signed-off-by: Ye Bin Reviewed-by: Jan Kara Link: https://patch.msgid.link/20260314075258.1317579-3-yebin@huaweicloud.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: introduce EXPORT_SYMBOL_FOR_EXT4_TEST() helper

2026-04-02T11:25:57+00:00

[ Upstream commit 49504a512587147dd6da3b4b08832ccc157b97dc ] Introduce EXPORT_SYMBOL_FOR_EXT4_TEST() helper for kuint test. Signed-off-by: Ye Bin Reviewed-by: Jan Kara Link: https://patch.msgid.link/20260314075258.1317579-2-yebin@huaweicloud.com Signed-off-by: Theodore Ts'o Stable-dep-of: 519b76ac0b31 ("ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M") Signed-off-by: Sasha Levin

netfs: Fix the handling of stream->front by removing it

2026-04-02T11:25:56+00:00

[ Upstream commit 0e764b9d46071668969410ec5429be0e2f38c6d3 ] The netfs_io_stream::front member is meant to point to the subrequest currently being collected on a stream, but it isn't actually used this way by direct write (which mostly ignores it). However, there's a tracepoint which looks at it. Further, stream->front is actually redundant with stream->subrequests.next. Fix the potential problem in the direct code by just removing the member and using stream->subrequests.next instead, thereby also simplifying the code. Fixes: a0b4c7a49137 ("netfs: Fix unbuffered/DIO writes to dispatch subrequests in strict sequence") Reported-by: Paulo Alcantara Signed-off-by: David Howells Link: https://patch.msgid.link/4158599.1774426817@warthog.procyon.org.uk Reviewed-by: Paulo Alcantara (Red Hat) cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

btrfs: fix lost error when running device stats on multiple devices fs

2026-04-02T11:25:56+00:00

[ Upstream commit 1c37d896b12dfd0d4c96e310b0033c6676933917 ] Whenever we get an error updating the device stats item for a device in btrfs_run_dev_stats() we allow the loop to go to the next device, and if updating the stats item for the next device succeeds, we end up losing the error we had from the previous device. Fix this by breaking out of the loop once we get an error and make sure it's returned to the caller. Since we are in the transaction commit path (and in the critical section actually), returning the error will result in a transaction abort. Fixes: 733f4fbbc108 ("Btrfs: read device stats on mount, write modified ones during commit") Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: fix leak of kobject name for sub-group space_info

2026-04-02T11:25:56+00:00

[ Upstream commit a4376d9a5d4c9610e69def3fc0b32c86a7ab7a41 ] When create_space_info_sub_group() allocates elements of space_info->sub_group[], kobject_init_and_add() is called for each element via btrfs_sysfs_add_space_info_type(). However, when check_removing_space_info() frees these elements, it does not call btrfs_sysfs_remove_space_info() on them. As a result, kobject_put() is not called and the associated kobj->name objects are leaked. This memory leak is reproduced by running the blktests test case zbd/009 on kernels built with CONFIG_DEBUG_KMEMLEAK. The kmemleak feature reports the following error: unreferenced object 0xffff888112877d40 (size 16): comm "mount", pid 1244, jiffies 4294996972 hex dump (first 16 bytes): 64 61 74 61 2d 72 65 6c 6f 63 00 c4 c6 a7 cb 7f data-reloc...... backtrace (crc 53ffde4d): __kmalloc_node_track_caller_noprof+0x619/0x870 kstrdup+0x42/0xc0 kobject_set_name_vargs+0x44/0x110 kobject_init_and_add+0xcf/0x150 btrfs_sysfs_add_space_info_type+0xfc/0x210 [btrfs] create_space_info_sub_group.constprop.0+0xfb/0x1b0 [btrfs] create_space_info+0x211/0x320 [btrfs] btrfs_init_space_info+0x15a/0x1b0 [btrfs] open_ctree+0x33c7/0x4a50 [btrfs] btrfs_get_tree.cold+0x9f/0x1ee [btrfs] vfs_get_tree+0x87/0x2f0 vfs_cmd_create+0xbd/0x280 __do_sys_fsconfig+0x3df/0x990 do_syscall_64+0x136/0x1540 entry_SYSCALL_64_after_hwframe+0x76/0x7e To avoid the leak, call btrfs_sysfs_remove_space_info() instead of kfree() for the elements. Fixes: f92ee31e031c ("btrfs: introduce btrfs_space_info sub-group") Link: https://lore.kernel.org/linux-block/b9488881-f18d-4f47-91a5-3c9bf63955a5@wdc.com/ Reviewed-by: Johannes Thumshirn Signed-off-by: Shin'ichiro Kawasaki Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: fix super block offset in error message in btrfs_validate_super()

2026-04-02T11:25:56+00:00

[ Upstream commit b52fe51f724385b3ed81e37e510a4a33107e8161 ] Fix the superblock offset mismatch error message in btrfs_validate_super(): we changed it so that it considers all the superblocks, but the message still assumes we're only looking at the first one. The change from %u to %llu is because we're changing from a constant to a u64. Fixes: 069ec957c35e ("btrfs: Refactor btrfs_check_super_valid") Reviewed-by: Qu Wenruo Signed-off-by: Mark Harmstone Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin

netfs: Fix read abandonment during retry

2026-04-02T11:25:55+00:00

[ Upstream commit 7e57523490cd2efb52b1ea97f2e0a74c0fb634cd ] Under certain circumstances, all the remaining subrequests from a read request will get abandoned during retry. The abandonment process expects the 'subreq' variable to be set to the place to start abandonment from, but it doesn't always have a useful value (it will be uninitialised on the first pass through the loop and it may point to a deleted subrequest on later passes). Fix the first jump to "abandon:" to set subreq to the start of the first subrequest expected to need retry (which, in this abandonment case, turned out unexpectedly to no longer have NEED_RETRY set). Also clear the subreq pointer after discarding superfluous retryable subrequests to cause an oops if we do try to access it. Fixes: ee4cdf7ba857 ("netfs: Speed up buffered reading") Signed-off-by: David Howells Link: https://patch.msgid.link/3775287.1773848338@warthog.procyon.org.uk Reviewed-by: Paulo Alcantara (Red Hat) cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

netfs: Fix NULL pointer dereference in netfs_unbuffered_write() on retry

2026-04-02T11:25:54+00:00

[ Upstream commit e9075e420a1eb3b52c60f3b95893a55e77419ce8 ] When a write subrequest is marked NETFS_SREQ_NEED_RETRY, the retry path in netfs_unbuffered_write() unconditionally calls stream->prepare_write() without checking if it is NULL. Filesystems such as 9P do not set the prepare_write operation, so stream->prepare_write remains NULL. When get_user_pages() fails with -EFAULT and the subrequest is flagged for retry, this results in a NULL pointer dereference at fs/netfs/direct_write.c:189. Fix this by mirroring the pattern already used in write_retry.c: if stream->prepare_write is NULL, skip renegotiation and directly reissue the subrequest via netfs_reissue_write(), which handles iterator reset, IN_PROGRESS flag, stats update and reissue internally. Fixes: a0b4c7a49137 ("netfs: Fix unbuffered/DIO writes to dispatch subrequests in strict sequence") Reported-by: syzbot+7227db0fbac9f348dba0@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7227db0fbac9f348dba0 Signed-off-by: Deepanshu Kartikey Link: https://patch.msgid.link/20260307043947.347092-1-kartikey406@gmail.com Tested-by: syzbot+7227db0fbac9f348dba0@syzkaller.appspotmail.com Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

netfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators

2026-04-02T11:25:54+00:00

[ Upstream commit 67e467a11f62ff64ad219dc6aa5459e132c79d14 ] When a process crashes and the kernel writes a core dump to a 9P filesystem, __kernel_write() creates an ITER_KVEC iterator. This iterator reaches netfs_limit_iter() via netfs_unbuffered_write(), which only handles ITER_FOLIOQ, ITER_BVEC and ITER_XARRAY iterator types, hitting the BUG() for any other type. Fix this by adding netfs_limit_kvec() following the same pattern as netfs_limit_bvec(), since both kvec and bvec are simple segment arrays with pointer and length fields. Dispatch it from netfs_limit_iter() when the iterator type is ITER_KVEC. Fixes: cae932d3aee5 ("netfs: Add func to calculate pagecount/size-limited span of an iterator") Reported-by: syzbot+9c058f0d63475adc97fd@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=9c058f0d63475adc97fd Tested-by: syzbot+9c058f0d63475adc97fd@syzkaller.appspotmail.com Signed-off-by: Deepanshu Kartikey Link: https://patch.msgid.link/20260307090041.359870-1-kartikey406@gmail.com Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

ksmbd: fix use-after-free and NULL deref in smb_grant_oplock()

2026-04-02T11:25:53+00:00

[ Upstream commit 48623ec358c1c600fa1e38368746f933e0f1a617 ] smb_grant_oplock() has two issues in the oplock publication sequence: 1) opinfo is linked into ci->m_op_list (via opinfo_add) before add_lease_global_list() is called. If add_lease_global_list() fails (kmalloc returns NULL), the error path frees the opinfo via __free_opinfo() while it is still linked in ci->m_op_list. Concurrent m_op_list readers (opinfo_get_list, or direct iteration in smb_break_all_levII_oplock) dereference the freed node. 2) opinfo->o_fp is assigned after add_lease_global_list() publishes the opinfo on the global lease list. A concurrent find_same_lease_key() can walk the lease list and dereference opinfo->o_fp->f_ci while o_fp is still NULL. Fix by restructuring the publication sequence to eliminate post-publish failure: - Set opinfo->o_fp before any list publication (fixes NULL deref). - Preallocate lease_table via alloc_lease_table() before opinfo_add() so add_lease_global_list() becomes infallible after publication. - Keep the original m_op_list publication order (opinfo_add before lease list) so concurrent opens via same_client_has_lease() and opinfo_get_list() still see the in-flight grant. - Use opinfo_put() instead of __free_opinfo() on err_out so that the RCU-deferred free path is used. This also requires splitting add_lease_global_list() to take a preallocated lease_table and changing its return type from int to void, since it can no longer fail. Fixes: 1dfd062caa16 ("ksmbd: fix use-after-free by using call_rcu() for oplock_info") Cc: stable@vger.kernel.org Signed-off-by: Werner Kasselman Reviewed-by: ChenXiaoSong Acked-by: Namjae Jeon Signed-off-by: Steve French [ adapted kmalloc_obj() macro to kmalloc(sizeof()) ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman