[ Upstream commit 66d938e89e ]
The filio lock has been released here, so there is no need to jump to
error_folio_unlock to release it again.
Reported-by: syzbot+b73c7d94a151e2ee1e9b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b73c7d94a151e2ee1e9b
Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com>
Acked-by: David Howells <dhowells@redhat.com>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ed4e6b5d64 ]
Syzbot hits a problem with enabled ref-verify, ignorebadroots and a
fuzzed/damaged extent tree. There's no fallback option like in other
places that can deal with it so disable the whole ref-verify as it is
just a debugging feature.
Reported-by: syzbot+9c3e0cdfbfe351b0bc0e@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/0000000000001b6052062139be1c@google.com/
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7b7387650d upstream.
Migration may be raced with fallocating hole. remove_inode_single_folio
will unmap the folio if the folio is still mapped. However, it's called
without folio lock. If the folio is migrated and the mapped pte has been
converted to migration entry, folio_mapped() returns false, and won't
unmap it. Due to extra refcount held by remove_inode_single_folio,
migration fails, restores migration entry to normal pte, and the folio is
mapped again. As a result, we triggered BUG in filemap_unaccount_folio.
The log is as follows:
BUG: Bad page cache in process hugetlb pfn:156c00
page: refcount:515 mapcount:0 mapping:0000000099fef6e1 index:0x0 pfn:0x156c00
head: order:9 mapcount:1 entire_mapcount:1 nr_pages_mapped:0 pincount:0
aops:hugetlbfs_aops ino:dcc dentry name(?):"my_hugepage_file"
flags: 0x17ffffc00000c1(locked|waiters|head|node=0|zone=2|lastcpupid=0x1fffff)
page_type: f4(hugetlb)
page dumped because: still mapped when deleted
CPU: 1 UID: 0 PID: 395 Comm: hugetlb Not tainted 6.17.0-rc5-00044-g7aac71907bde-dirty #484 NONE
Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
Call Trace:
<TASK>
dump_stack_lvl+0x4f/0x70
filemap_unaccount_folio+0xc4/0x1c0
__filemap_remove_folio+0x38/0x1c0
filemap_remove_folio+0x41/0xd0
remove_inode_hugepages+0x142/0x250
hugetlbfs_fallocate+0x471/0x5a0
vfs_fallocate+0x149/0x380
Hold folio lock before checking if the folio is mapped to avold race with
migration.
Link: https://lkml.kernel.org/r/20250912074139.3575005-1-tujinjiang@huawei.com
Fixes: 4aae8d1c05 ("mm/hugetlbfs: unmap pages if page fault raced with hole punch")
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 28aa29986d upstream.
When the PAGEMAP_SCAN ioctl is invoked with vec_len = 0 reaches
pagemap_scan_backout_range(), kernel panics with null-ptr-deref:
[ 44.936808] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
[ 44.937797] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
[ 44.938391] CPU: 1 UID: 0 PID: 2480 Comm: reproducer Not tainted 6.17.0-rc6 #22 PREEMPT(none)
[ 44.939062] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 44.939935] RIP: 0010:pagemap_scan_thp_entry.isra.0+0x741/0xa80
<snip registers, unreliable trace>
[ 44.946828] Call Trace:
[ 44.947030] <TASK>
[ 44.949219] pagemap_scan_pmd_entry+0xec/0xfa0
[ 44.952593] walk_pmd_range.isra.0+0x302/0x910
[ 44.954069] walk_pud_range.isra.0+0x419/0x790
[ 44.954427] walk_p4d_range+0x41e/0x620
[ 44.954743] walk_pgd_range+0x31e/0x630
[ 44.955057] __walk_page_range+0x160/0x670
[ 44.956883] walk_page_range_mm+0x408/0x980
[ 44.958677] walk_page_range+0x66/0x90
[ 44.958984] do_pagemap_scan+0x28d/0x9c0
[ 44.961833] do_pagemap_cmd+0x59/0x80
[ 44.962484] __x64_sys_ioctl+0x18d/0x210
[ 44.962804] do_syscall_64+0x5b/0x290
[ 44.963111] entry_SYSCALL_64_after_hwframe+0x76/0x7e
vec_len = 0 in pagemap_scan_init_bounce_buffer() means no buffers are
allocated and p->vec_buf remains set to NULL.
This breaks an assumption made later in pagemap_scan_backout_range(), that
page_region is always allocated for p->vec_buf_index.
Fix it by explicitly checking p->vec_buf for NULL before dereferencing.
Other sites that might run into same deref-issue are already (directly or
transitively) protected by checking p->vec_buf.
Note:
From PAGEMAP_SCAN man page, it seems vec_len = 0 is valid when no output
is requested and it's only the side effects caller is interested in,
hence it passes check in pagemap_scan_get_args().
This issue was found by syzkaller.
Link: https://lkml.kernel.org/r/20250922082206.6889-1-acsjakub@amazon.de
Fixes: 52526ca7fd ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs")
Signed-off-by: Jakub Acs <acsjakub@amazon.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Jinjiang Tu <tujinjiang@huawei.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Penglei Jiang <superman.xpt@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9158c6bb24 upstream.
afs_put_server() accessed server->debug_id before the NULL check, which
could lead to a null pointer dereference. Move the debug_id assignment,
ensuring we never dereference a NULL server pointer.
Fixes: 2757a4dc18 ("afs: Fix access after dec in put functions")
Cc: stable@vger.kernel.org
Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
Acked-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fbe2dc6a9c ]
In smb2_compound_op(), the loop that processes each command's response
uses wrong indices when accessing response bufferes.
This incorrect indexing leads to improper handling of command results.
Also, if incorrectly computed index is greather than or equal to
MAX_COMPOUND, it can cause out-of-bounds accesses.
Fixes: 3681c74d34 ("smb: client: handle lack of EA support in smb2_query_path_info()") # 6.14
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3d1267475b ]
Commit 15ae0410c37a79 ("btrfs-progs: add error handling for
device_get_partition_size_fd_stat()") in btrfs-progs inadvertently
changed it so that if the BLKGETSIZE64 ioctl on a block device returned
a size of 0, this was no longer seen as an error condition.
Unfortunately this is how disconnected NBD devices behave, meaning that
with btrfs-progs 6.16 it's now possible to add a device you can't
remove:
# btrfs device add /dev/nbd0 /root/temp
# btrfs device remove /dev/nbd0 /root/temp
ERROR: error removing device '/dev/nbd0': Invalid argument
This check should always have been done kernel-side anyway, so add a
check in btrfs_init_new_device() that the new device doesn't have a size
less than BTRFS_DEVICE_RANGE_RESERVED (i.e. 1 MB).
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Mark Harmstone <mark@harmstone.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f7f8925017 ]
This makes it safer during the disconnect and avoids
requeueing.
It's ok to call disable_work[_sync]() more than once.
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Fixes: 0626e6641f ("cifsd: add server handler for central processing and tranport layers")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1cde0a74a7 ]
If we are using a hardcoded delay of 0 there's no point in
using delayed_work it only adds confusion.
The client also uses a normal work_struct and now
it is easier to move it to the common smbdirect_socket.
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Fixes: 0626e6641f ("cifsd: add server handler for central processing and tranport layers")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit daac51c703 ]
During tests of another unrelated patch I was able to trigger this
error: Objects remaining on __kmem_cache_shutdown()
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Long Li <longli@microsoft.com>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Fixes: f198186aa9 ("CIFS: SMBD: Establish SMB Direct connection")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 93ed9a2951 ]
Fix the following case where the client would end up closing both
deferred files (foo.tmp & foo) after unlink(foo) due to strstr() call
in cifs_close_deferred_file_under_dentry():
fd1 = openat(AT_FDCWD, "foo", O_WRONLY|O_CREAT|O_TRUNC, 0666);
fd2 = openat(AT_FDCWD, "foo.tmp", O_WRONLY|O_CREAT|O_TRUNC, 0666);
close(fd1);
close(fd2);
unlink("foo");
Fixes: e3fc065682 ("cifs: Deferred close performance improvements")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Cc: Frank Sorenson <sorenson@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 96fa515e70 upstream.
[BUG]
Inside check_inode_ref(), we need to make sure every structure,
including the btrfs_inode_extref header, is covered by the item. But
our code is incorrectly using "sizeof(iref)", where @iref is just a
pointer.
This means "sizeof(iref)" will always be "sizeof(void *)", which is much
smaller than "sizeof(struct btrfs_inode_extref)".
This will allow some bad inode extrefs to sneak in, defeating tree-checker.
[FIX]
Fix the typo by calling "sizeof(*iref)", which is the same as
"sizeof(struct btrfs_inode_extref)", and will be the correct behavior we
want.
Fixes: 71bf92a9b8 ("btrfs: tree-checker: Add check for INODE_REF")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 025e87f8ea upstream.
When accessing one of the files under /sys/fs/nilfs2/features when
CONFIG_CFI_CLANG is enabled, there is a CFI violation:
CFI failure at kobj_attr_show+0x59/0x80 (target: nilfs_feature_revision_show+0x0/0x30; expected type: 0xfc392c4d)
...
Call Trace:
<TASK>
sysfs_kf_seq_show+0x2a6/0x390
? __cfi_kobj_attr_show+0x10/0x10
kernfs_seq_show+0x104/0x15b
seq_read_iter+0x580/0xe2b
...
When the kobject of the kset for /sys/fs/nilfs2 is initialized, its ktype
is set to kset_ktype, which has a ->sysfs_ops of kobj_sysfs_ops. When
nilfs_feature_attr_group is added to that kobject via
sysfs_create_group(), the kernfs_ops of each files is sysfs_file_kfops_rw,
which will call sysfs_kf_seq_show() when ->seq_show() is called.
sysfs_kf_seq_show() in turn calls kobj_attr_show() through
->sysfs_ops->show(). kobj_attr_show() casts the provided attribute out to
a 'struct kobj_attribute' via container_of() and calls ->show(), resulting
in the CFI violation since neither nilfs_feature_revision_show() nor
nilfs_feature_README_show() match the prototype of ->show() in 'struct
kobj_attribute'.
Resolve the CFI violation by adjusting the second parameter in
nilfs_feature_{revision,README}_show() from 'struct attribute' to 'struct
kobj_attribute' to match the expected prototype.
Link: https://lkml.kernel.org/r/20250906144410.22511-1-konishi.ryusuke@gmail.com
Fixes: aebe17f684 ("nilfs2: add /sys/fs/nilfs2/features group")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202509021646.bc78d9ef-lkp@intel.com/
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e1868ba37f upstream.
This is inspired by the check for data_offset + data_length.
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: stable@vger.kernel.org
Fixes: 2ea086e35c ("ksmbd: add buffer validation for smb direct")
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5282491fc4 upstream.
If data_offset and data_length of smb_direct_data_transfer struct are
invalid, out of bounds issue could happen.
This patch validate data_offset and data_length field in recv_done.
Cc: stable@vger.kernel.org
Fixes: 2ea086e35c ("ksmbd: add buffer validation for smb direct")
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Reported-by: Luigino Camastra, Aisle Research <luigino.camastra@aisle.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b62fd63ade ]
The offset for an extref item's key is not the object ID of the parent
dir, otherwise we would not need the extref item and would use plain ref
items. Instead the offset is the result of a hash computation that uses
the object ID of the parent dir and the name associated to the entry.
So fix this by setting the key offset at replay_one_name() to be the
result of calling btrfs_extref_hash().
Fixes: 725af92a62 ("btrfs: Open-code name_in_log_ref in replay_one_name")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9786531399 ]
[BUG]
With 64K page size (aarch64 with 64K page size config) and 4K btrfs
block size, the following workload can easily lead to a corrupted read:
mkfs.btrfs -f -s 4k $dev > /dev/null
mount -o compress $dev $mnt
xfs_io -f -c "pwrite -S 0xff 0 64k" $mnt/base > /dev/null
echo "correct result:"
od -Ad -t x1 $mnt/base
xfs_io -f -c "reflink $mnt/base 32k 0 32k" \
-c "reflink $mnt/base 0 32k 32k" \
-c "pwrite -S 0xff 60k 4k" $mnt/new > /dev/null
echo "incorrect result:"
od -Ad -t x1 $mnt/new
umount $mnt
This shows the following result:
correct result:
0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0065536
incorrect result:
0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0032768 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0061440 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0065536
Notice the zero in the range [32K, 60K), which is incorrect.
[CAUSE]
With extra trace printk, it shows the following events during od:
(some unrelated info removed like CPU and context)
od-3457 btrfs_do_readpage: enter r/i=5/258 folio=0(65536) prev_em_start=0000000000000000
The "r/i" is indicating the root and inode number. In our case the file
"new" is using ino 258 from fs tree (root 5).
Here notice the @prev_em_start pointer is NULL. This means the
btrfs_do_readpage() is called from btrfs_read_folio(), not from
btrfs_readahead().
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=0 got em start=0 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=4096 got em start=0 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=8192 got em start=0 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=12288 got em start=0 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=16384 got em start=0 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=20480 got em start=0 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=24576 got em start=0 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=28672 got em start=0 len=32768
These above 32K blocks will be read from the first half of the
compressed data extent.
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=32768 got em start=32768 len=32768
Note here there is no btrfs_submit_compressed_read() call. Which is
incorrect now.
Although both extent maps at 0 and 32K are pointing to the same compressed
data, their offsets are different thus can not be merged into the same
read.
So this means the compressed data read merge check is doing something
wrong.
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=36864 got em start=32768 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=40960 got em start=32768 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=45056 got em start=32768 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=49152 got em start=32768 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=53248 got em start=32768 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=57344 got em start=32768 len=32768
od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=61440 skip uptodate
od-3457 btrfs_submit_compressed_read: cb orig_bio: file off=0 len=61440
The function btrfs_submit_compressed_read() is only called at the end of
folio read. The compressed bio will only have an extent map of range [0,
32K), but the original bio passed in is for the whole 64K folio.
This will cause the decompression part to only fill the first 32K,
leaving the rest untouched (aka, filled with zero).
This incorrect compressed read merge leads to the above data corruption.
There were similar problems that happened in the past, commit 808f80b467
("Btrfs: update fix for read corruption of compressed and shared
extents") is doing pretty much the same fix for readahead.
But that's back to 2015, where btrfs still only supports bs (block size)
== ps (page size) cases.
This means btrfs_do_readpage() only needs to handle a folio which
contains exactly one block.
Only btrfs_readahead() can lead to a read covering multiple blocks.
Thus only btrfs_readahead() passes a non-NULL @prev_em_start pointer.
With v5.15 kernel btrfs introduced bs < ps support. This breaks the above
assumption that a folio can only contain one block.
Now btrfs_read_folio() can also read multiple blocks in one go.
But btrfs_read_folio() doesn't pass a @prev_em_start pointer, thus the
existing bio force submission check will never be triggered.
In theory, this can also happen for btrfs with large folios, but since
large folio is still experimental, we don't need to bother it, thus only
bs < ps support is affected for now.
[FIX]
Instead of passing @prev_em_start to do the proper compressed extent
check, introduce one new member, btrfs_bio_ctrl::last_em_start, so that
the existing bio force submission logic will always be triggered.
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[ Adjust context ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9e9ff875e4 ]
We recently received a report of poor performance doing sequential
buffered reads of a file with compressed extents. With bs=128k, a naive
sequential dd ran as fast on a compressed file as on an uncompressed
(1.2GB/s on my reproducing system) while with bs<32k, this performance
tanked down to ~300MB/s.
i.e., slow:
dd if=some-compressed-file of=/dev/null bs=4k count=X
vs fast:
dd if=some-compressed-file of=/dev/null bs=128k count=Y
The cause of this slowness is overhead to do with looking up extent_maps
to enable readahead pre-caching on compressed extents
(add_ra_bio_pages()), as well as some overhead in the generic VFS
readahead code we hit more in the slow case. Notably, the main
difference between the two read sizes is that in the large sized request
case, we call btrfs_readahead() relatively rarely while in the smaller
request we call it for every compressed extent. So the fast case stays
in the btrfs readahead loop:
while ((folio = readahead_folio(rac)) != NULL)
btrfs_do_readpage(folio, &em_cached, &bio_ctrl, &prev_em_start);
where the slower one breaks out of that loop every time. This results in
calling add_ra_bio_pages a lot, doing lots of extent_map lookups,
extent_map locking, etc.
This happens because although add_ra_bio_pages() does add the
appropriate un-compressed file pages to the cache, it does not
communicate back to the ractl in any way. To solve this, we should be
using readahead_expand() to signal to readahead to expand the readahead
window.
This change passes the readahead_control into the btrfs_bio_ctrl and in
the case of compressed reads sets the expansion to the size of the
extent_map we already looked up anyway. It skips the subpage case as
that one already doesn't do add_ra_bio_pages().
With this change, whether we use bs=4k or bs=128k, btrfs expands the
readahead window up to the largest compressed extent we have seen so far
(in the trivial example: 128k) and the call stacks of the two modes look
identical. Notably, we barely call add_ra_bio_pages at all. And the
performance becomes identical as well. So this change certainly "fixes"
this performance problem.
Of course, it does seem to beg a few questions:
1. Will this waste too much page cache with a too large ra window?
2. Will this somehow cause bugs prevented by the more thoughtful
checking in add_ra_bio_pages?
3. Should we delete add_ra_bio_pages?
My stabs at some answers:
1. Hard to say. See attempts at generic performance testing below. Is
there a "readahead_shrink" we should be using? Should we expand more
slowly, by half the remaining em size each time?
2. I don't think so. Since the new behavior is indistinguishable from
reading the file with a larger read size passed in, I don't see why
one would be safe but not the other.
3. Probably! I tested that and it was fine in fstests, and it seems like
the pages would get re-used just as well in the readahead case.
However, it is possible some reads that use page cache but not
btrfs_readahead() could suffer. I will investigate this further as a
follow up.
I tested the performance implications of this change in 3 ways (using
compress-force=zstd:3 for compression):
Directly test the affected workload of small sequential reads on a
compressed file (improved from ~250MB/s to ~1.2GB/s)
==========for-next==========
dd /mnt/lol/non-cmpr 4k
1048576+0 records in
1048576+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 6.02983 s, 712 MB/s
dd /mnt/lol/non-cmpr 128k
32768+0 records in
32768+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 5.92403 s, 725 MB/s
dd /mnt/lol/cmpr 4k
1048576+0 records in
1048576+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 17.8832 s, 240 MB/s
dd /mnt/lol/cmpr 128k
32768+0 records in
32768+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 3.71001 s, 1.2 GB/s
==========ra-expand==========
dd /mnt/lol/non-cmpr 4k
1048576+0 records in
1048576+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 6.09001 s, 705 MB/s
dd /mnt/lol/non-cmpr 128k
32768+0 records in
32768+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 6.07664 s, 707 MB/s
dd /mnt/lol/cmpr 4k
1048576+0 records in
1048576+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 3.79531 s, 1.1 GB/s
dd /mnt/lol/cmpr 128k
32768+0 records in
32768+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 3.69533 s, 1.2 GB/s
Built the linux kernel from clean (no change)
Ran fsperf. Mostly neutral results with some improvements and
regressions here and there.
Reported-by: Dimitrios Apostolou <jimis@gmx.net>
Link: https://lore.kernel.org/linux-btrfs/34601559-6c16-6ccc-1793-20a97ca0dbba@gmx.net/
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
[ Assert doesn't take a format string ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bec324f33d upstream.
When the parent directory's i_rwsem is not locked, req->r_parent may become
stale due to concurrent operations (e.g. rename) between dentry lookup and
message creation. Validate that r_parent matches the encoded parent inode
and update to the correct inode if a mismatch is detected.
[ idryomov: folded a follow-up fix from Alex to drop extra reference
from ceph_get_reply_dir() in ceph_fill_trace():
ceph_get_reply_dir() may return a different, referenced inode when
r_parent is stale and the parent directory lock is not held.
ceph_fill_trace() used that inode but failed to drop the reference
when it differed from req->r_parent, leaking an inode reference.
Keep the directory inode in a local variable and iput() it at
function end if it does not match req->r_parent. ]
Cc: stable@vger.kernel.org
Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 15f519e9f8 upstream.
Add validation to ensure the cached parent directory inode matches the
directory info in MDS replies. This prevents client-side race conditions
where concurrent operations (e.g. rename) cause r_parent to become stale
between request initiation and reply processing, which could lead to
applying state changes to incorrect directory inodes.
[ idryomov: folded a kerneldoc fixup and a follow-up fix from Alex to
move CEPH_CAP_PIN reference when r_parent is updated:
When the parent directory lock is not held, req->r_parent can become
stale and is updated to point to the correct inode. However, the
associated CEPH_CAP_PIN reference was not being adjusted. The
CEPH_CAP_PIN is a reference on an inode that is tracked for
accounting purposes. Moving this pin is important to keep the
accounting balanced. When the pin was not moved from the old parent
to the new one, it created two problems: The reference on the old,
stale parent was never released, causing a reference leak.
A reference for the new parent was never acquired, creating the risk
of a reference underflow later in ceph_mdsc_release_request(). This
patch corrects the logic by releasing the pin from the old parent and
acquiring it for the new parent when r_parent is switched. This
ensures reference accounting stays balanced. ]
Cc: stable@vger.kernel.org
Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1e08938c36 upstream.
The FUSE protocol uses struct fuse_write_out to convey the return value of
copy_file_range, which is restricted to uint32_t. But the COPY_FILE_RANGE
interface supports a 64-bit size copies.
Currently the number of bytes copied is silently truncated to 32-bit, which
may result in poor performance or even failure to copy in case of
truncation to zero.
Reported-by: Florian Weimer <fweimer@redhat.com>
Closes: https://lore.kernel.org/all/lhuh5ynl8z5.fsf@oldenburg.str.redhat.com/
Fixes: 88bc7d5097 ("fuse: add support for copy_file_range()")
Cc: <stable@vger.kernel.org> # v4.20
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e5203209b3 upstream.
Just like write(), copy_file_range() should check if the return value is
less or equal to the requested number of bytes.
Reported-by: Chunsheng Luo <luochunsheng@ustc.edu>
Closes: https://lore.kernel.org/all/20250807062425.694-1-luochunsheng@ustc.edu/
Fixes: 88bc7d5097 ("fuse: add support for copy_file_range()")
Cc: <stable@vger.kernel.org> # v4.20
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e9c8da670e upstream.
We do not support passthrough operations other than read/write on
regular file, so allowing non-regular backing files makes no sense.
Fixes: efad7153bf ("fuse: allow O_PATH fd for FUSE_DEV_IOC_BACKING_OPEN")
Cc: stable@vger.kernel.org
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Bernd Schubert <bschubert@ddn.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f6a6c28005 upstream.
There is a race condition between inode eviction and inode caching that
can cause a live struct btrfs_inode to be missing from the root->inodes
xarray. Specifically, there is a window during evict() between the inode
being unhashed and deleted from the xarray. If btrfs_iget() is called
for the same inode in that window, it will be recreated and inserted
into the xarray, but then eviction will delete the new entry, leaving
nothing in the xarray:
Thread 1 Thread 2
---------------------------------------------------------------
evict()
remove_inode_hash()
btrfs_iget_path()
btrfs_iget_locked()
btrfs_read_locked_inode()
btrfs_add_inode_to_root()
destroy_inode()
btrfs_destroy_inode()
btrfs_del_inode_from_root()
__xa_erase
In turn, this can cause issues for subvolume deletion. Specifically, if
an inode is in this lost state, and all other inodes are evicted, then
btrfs_del_inode_from_root() will call btrfs_add_dead_root() prematurely.
If the lost inode has a delayed_node attached to it, then when
btrfs_clean_one_deleted_snapshot() calls btrfs_kill_all_delayed_nodes(),
it will loop forever because the delayed_nodes xarray will never become
empty (unless memory pressure forces the inode out). We saw this
manifest as soft lockups in production.
Fix it by only deleting the xarray entry if it matches the given inode
(using __xa_cmpxchg()).
Fixes: 310b2f5d5a ("btrfs: use an xarray to track open inodes in a root")
Cc: stable@vger.kernel.org # 6.11+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Co-authored-by: Leo Martins <loemra.dev@gmail.com>
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit de134cb54c upstream.
The following workload on a squota enabled fs:
btrfs subvol create mnt/subvol
# ensure subvol extents get accounted
sync
btrfs qgroup create 1/1 mnt
btrfs qgroup assign mnt/subvol 1/1 mnt
btrfs qgroup delete mnt/subvol
# make the cleaner thread run
btrfs filesystem sync mnt
sleep 1
btrfs filesystem sync mnt
btrfs qgroup destroy 1/1 mnt
will fail with EBUSY. The reason is that 1/1 does the quick accounting
when we assign subvol to it, gaining its exclusive usage as excl and
excl_cmpr. But then when we delete subvol, the decrement happens via
record_squota_delta() which does not update excl_cmpr, as squotas does
not make any distinction between compressed and normal extents. Thus,
we increment excl_cmpr but never decrement it, and are unable to delete
1/1. The two possible fixes are to make squota always mirror excl and
excl_cmpr or to make the fast accounting separately track the plain and
cmpr numbers. The latter felt cleaner to me so that is what I opted for.
Fixes: 1e0e9d5771 ("btrfs: add helper for recording simple quota deltas")
CC: stable@vger.kernel.org # 6.12+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0ce9398aa0 ]
Commit 2ce3d282bd ("proc: fix missing pde_set_flags() for net proc
files") missed a key part in the definition of proc_dir_entry:
union {
const struct proc_ops *proc_ops;
const struct file_operations *proc_dir_ops;
};
So dereference of ->proc_ops assumes it is a proc_ops structure results in
type confusion and make NULL check for 'proc_ops' not work for proc dir.
Add !S_ISDIR(dp->mode) test before calling pde_set_flags() to fix it.
Link: https://lkml.kernel.org/r/20250904135715.3972782-1-wangzijie1@honor.com
Fixes: 2ce3d282bd ("proc: fix missing pde_set_flags() for net proc files")
Signed-off-by: wangzijie <wangzijie1@honor.com>
Reported-by: Brad Spengler <spender@grsecurity.net>
Closes: https://lore.kernel.org/all/20250903065758.3678537-1-wangzijie1@honor.com/
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Stefano Brivio <sbrivio@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit dd2fa82473 ]
Typo in ff_lseg_match_mirrors makes the diff ineffective. This results
in merge happening all the time. Merge happening all the time is
problematic because it marks lsegs invalid. Marking lsegs invalid
causes all outstanding IO to get restarted with EAGAIN and connections
to get closed.
Closing connections constantly triggers race conditions in the RDMA
implementation...
Fixes: 660d1eb223 ("pNFS/flexfile: Don't merge layout segments if the mirrors don't match")
Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b7b8574225 ]
If we're truncating part of the folio, then we need to write out the
data on the part that is not covered by the cancellation.
Fixes: d47992f86b ("mm: change invalidatepage prototype to accept length")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ca247c8990 ]
Ensure that all O_DIRECT reads and writes complete before copying a file
range, so that the destination is up to date.
Fixes: a5864c999d ("NFS: Do not serialise O_DIRECT reads and writes")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c80ebeba11 ]
Ensure that all O_DIRECT reads and writes complete before cloning a file
range, so that both the source and destination are up to date.
Fixes: a5864c999d ("NFS: Do not serialise O_DIRECT reads and writes")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b93128f297 ]
Ensure that all O_DIRECT reads and writes complete before calling
fallocate so that we don't race w.r.t. attribute updates.
Fixes: 99f2378322 ("NFSv4.2: Always flush out writes in nfs42_proc_fallocate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9eb90f4354 ]
Ensure that all O_DIRECT reads and writes are complete, and prevent the
initiation of new i/o until the setattr operation that will truncate the
file is complete.
Fixes: a5864c999d ("NFS: Do not serialise O_DIRECT reads and writes")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 38a125b315 ]
This allows killing processes that wait for a lock when one process is
stuck waiting for the NFS server. This aims to complete the coverage
of NFS operations being killable, like nfs_direct_wait() does, for
example.
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Stable-dep-of: 9eb90f4354 ("NFS: Serialise O_DIRECT i/o and truncate()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 992203a1fb ]
Otherwise if the nfsd filecache code releases the nfsd_file
immediately, it can trigger the BUG_ON(cred == current->cred) in
__put_cred() when it puts the nfsd_file->nf_file->f-cred.
Fixes: b9f5dd57f4 ("nfs/localio: use dedicated workqueues for filesystem read and write")
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Link: https://lore.kernel.org/r/20250807164938.2395136-1-smayhew@redhat.com
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3feec68563 ]
This commit simply adds the required O_DIRECT plumbing. It doesn't
address the fact that NFS doesn't ensure all writes are page aligned
(nor device logical block size aligned as required by O_DIRECT).
Because NFS will read-modify-write for IO that isn't aligned, LOCALIO
will not use O_DIRECT semantics by default if/when an application
requests the use of O_DIRECT. Allow the use of O_DIRECT semantics by:
1: Adding a flag to the nfs_pgio_header struct to allow the NFS
O_DIRECT layer to signal that O_DIRECT was used by the application
2: Adding a 'localio_O_DIRECT_semantics' NFS module parameter that
when enabled will cause LOCALIO to use O_DIRECT semantics (this may
cause IO to fail if applications do not properly align their IO).
This commit is derived from code developed by Weston Andros Adamson.
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Stable-dep-of: 992203a1fb ("nfs/localio: restore creds before releasing pageio data")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0978e5b85f ]
Push the read_iter and write_iter availability checks down to
nfs_do_local_read and nfs_do_local_write respectively.
This eliminates a redundant nfs_to->nfsd_file_file() call.
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Stable-dep-of: 992203a1fb ("nfs/localio: restore creds before releasing pageio data")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4fb2b677fc ]
nfs_server_set_fsinfo() shouldn't assume that NFS_CAP_XATTR is unset
on entry to the function.
Fixes: b78ef845c3 ("NFSv4.2: query the server for extended attribute support")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b3ac334360 ]
_nfs4_server_capabilities() should clear capabilities that are not
supported by the server.
Fixes: d2a00cceb9 ("NFSv4: Detect support for OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit dd5a8621b8 ]
_nfs4_server_capabilities() is expected to clear any flags that are not
supported by the server.
Fixes: 8a59bb93b7 ("NFSv4 store server support for fs_location attribute")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 31f1a960ad ]
Don't clear the capabilities that are not going to get reset by the call
to _nfs4_server_capabilities().
Reported-by: Scott Haiden <scott.b.haiden@gmail.com>
Fixes: b01f21cacd ("NFS: Fix the setting of capabilities when automounting a new filesystem")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5a46d2339a ]
Recent commit f06bedfa62 ("pNFS/flexfiles: don't attempt pnfs on fatal DS
errors") has changed the error return type of ff_layout_choose_ds_for_read() from
NULL to an error pointer. However, not all code paths have been updated
to match the change. Thus, some non-NULL checks will accept error pointers
as a valid return value.
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Suggested-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: f06bedfa62 ("pNFS/flexfiles: don't attempt pnfs on fatal DS errors")
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9e28059d56 ]
This patch addresses an issue where some files in case-insensitive
directories become inaccessible due to changes in how the kernel
function, utf8_casefold(), generates case-folded strings from the
commit 5c26d2f1d3 ("unicode: Don't special case ignorable code
points").
There are good reasons why this change should be made; it's actually
quite stupid that Unicode seems to think that the characters ❤ and ❤️
should be casefolded. Unfortimately because of the backwards
compatibility issue, this commit was reverted in 231825b2e1.
This problem is addressed by instituting a brute-force linear fallback
if a lookup fails on case-folded directory, which does result in a
performance hit when looking up files affected by the changing how
thekernel treats ignorable Uniode characters, or when attempting to
look up non-existent file names. So this fallback can be disabled by
setting an encoding flag if in the future, the system administrator or
the manufacturer of a mobile handset or tablet can be sure that there
was no opportunity for a kernel to insert file names with incompatible
encodings.
Fixes: 5c26d2f1d3 ("unicode: Don't special case ignorable code points")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bb585591eb ]
Commit 620c266f39 ("fhandle: relax open_by_handle_at() permission
checks") relaxed the coditions for decoding a file handle from non init
userns.
The conditions are that that decoded dentry is accessible from the user
provided mountfd (or to fs root) and that all the ancestors along the
path have a valid id mapping in the userns.
These conditions are intentionally more strict than the condition that
the decoded dentry should be "lookable" by path from the mountfd.
For example, the path /home/amir/dir/subdir is lookable by path from
unpriv userns of user amir, because /home perms is 755, but the owner of
/home does not have a valid id mapping in unpriv userns of user amir.
The current code did not check that the decoded dentry itself has a
valid id mapping in the userns. There is no security risk in that,
because that final open still performs the needed permission checks,
but this is inconsistent with the checks performed on the ancestors,
so the behavior can be a bit confusing.
Add the check for the decoded dentry itself, so that the entire path,
including the last component has a valid id mapping in the userns.
Fixes: 620c266f39 ("fhandle: relax open_by_handle_at() permission checks")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/20250827194309.1259650-1-amir73il@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ce2f26e737 upstream.
Presently we always BUG_ON if trying to start a transaction on a journal marked
with JBD2_UNMOUNT, since this should never happen. However, while ltp running
stress tests, it was observed that in case of some error handling paths, it is
possible for update_super_work to start a transaction after the journal is
destroyed eg:
(umount)
ext4_kill_sb
kill_block_super
generic_shutdown_super
sync_filesystem /* commits all txns */
evict_inodes
/* might start a new txn */
ext4_put_super
flush_work(&sbi->s_sb_upd_work) /* flush the workqueue */
jbd2_journal_destroy
journal_kill_thread
journal->j_flags |= JBD2_UNMOUNT;
jbd2_journal_commit_transaction
jbd2_journal_get_descriptor_buffer
jbd2_journal_bmap
ext4_journal_bmap
ext4_map_blocks
...
ext4_inode_error
ext4_handle_error
schedule_work(&sbi->s_sb_upd_work)
/* work queue kicks in */
update_super_work
jbd2_journal_start
start_this_handle
BUG_ON(journal->j_flags &
JBD2_UNMOUNT)
Hence, introduce a new mount flag to indicate journal is destroying and only do
a journaled (and deferred) update of sb if this flag is not set. Otherwise, just
fallback to an un-journaled commit.
Further, in the journal destroy path, we have the following sequence:
1. Set mount flag indicating journal is destroying
2. force a commit and wait for it
3. flush pending sb updates
This sequence is important as it ensures that, after this point, there is no sb
update that might be journaled so it is safe to update the sb outside the
journal. (To avoid race discussed in 2d01ddc866)
Also, we don't need a similar check in ext4_grp_locked_error since it is only
called from mballoc and AFAICT it would be always valid to schedule work here.
Fixes: 2d01ddc866 ("ext4: save error info to sb through journal if available")
Reported-by: Mahesh Kumar <maheshkumar657g@gmail.com>
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/9613c465d6ff00cd315602f99283d5f24018c3f7.1742279837.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5a02a6204c upstream.
Define an ext4 wrapper over jbd2_journal_destroy to make sure we
have consistent behavior during journal destruction. This will also
come useful in the next patch where we add some ext4 specific logic
in the destroy path.
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/c3ba78c5c419757e6d5f2d8ebb4a8ce9d21da86a.1742279837.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1f282cdc1d upstream.
may_decode_fh() is calling has_locked_children() while holding no locks.
That's an oopsable race...
The rest of the callers are safe since they are holding namespace_sem and
are guaranteed a positive refcount on the mount in question.
Rename the current has_locked_children() to __has_locked_children(), make
it static and switch the fs/namespace.c users to it.
Make has_locked_children() a wrapper for __has_locked_children(), calling
the latter under read_seqlock_excl(&mount_lock).
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Fixes: 620c266f39 ("fhandle: relax open_by_handle_at() permission checks")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[ Harshit: Resolved conflicts due to missing commit:
db04662e2f ("fs: allow detached mounts in clone_private_mount()") in
linux-6.12.y ]
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 70bccd9855 upstream.
There can be a NULL pointer dereference bug here. NULL is passed to
__cifs_sfu_make_node without checks, which passes it unchecked to
cifs_strndup_to_utf16, which in turn passes it to
cifs_local_to_utf16_bytes where '*from' is dereferenced, causing a crash.
This patch adds a check for NULL 'src' in cifs_strndup_to_utf16 and
returns NULL early to prevent dereferencing NULL pointer.
Found by Linux Verification Center (linuxtesting.org) with SVACE
Signed-off-by: Makar Semyonov <m.semenov@tssltd.ru>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
