Since commit 5cbcb62ddd ("fs/proc: fix softlockup in __read_vmcore") the
number of softlockups in __read_vmcore at kdump time have gone down, but
they still happen sometimes.
In a memory constrained environment like the kdump image, a softlockup is
not just a harmless message, but it can interfere with things like RCU
freeing memory, causing the crashdump to get stuck.
The second loop in __read_vmcore has a lot more opportunities for natural
sleep points, like scheduling out while waiting for a data write to
happen, but apparently that is not always enough.
Add a cond_resched() to the second loop in __read_vmcore to (hopefully)
get rid of the softlockups.
Link: https://lkml.kernel.org/r/20250110102821.2a37581b@fangorn
Fixes: 5cbcb62ddd ("fs/proc: fix softlockup in __read_vmcore")
Signed-off-by: Rik van Riel <riel@surriel.com>
Reported-by: Breno Leitao <leitao@debian.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull driver core and debugfs fixes from Greg KH:
"Here are some small driver core and debugfs fixes that resolve some
reported problems:
- debugfs runtime error reporting fixes
- topology cpumask race-condition fix
- MAINTAINERS file email update
All of these have been in linux-next this week with no reported
issues"
* tag 'driver-core-6.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
fs: debugfs: fix open proxy for unsafe files
MAINTAINERS: align Danilo's maintainer entries
topology: Keep the cpumask unchanged when printing cpumap
debugfs: fix missing mutex_destroy() in short_fops case
fs: debugfs: differentiate short fops with proxy ops
Pull smb client fix from Steve French:
- fix unneeded session setup retry due to stale password e.g. for DFS
automounts
* tag '6.13-rc6-SMB3-client-fix' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: sync the root session and superblock context passwords before automounting
strcpy() should not be used with destination potentially overlapping
the source; what's more, strscpy() in there is pointless - we already
know the amount we want to copy; might as well use memcpy().
Fixes: c278e81b8a "hostfs: Remove open coded strcpy()"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Commit ab04de60ae ("NFSD: Optimize nfsd4_encode_fattr()") replaced
the use of write_bytes_to_xdr_buf() because it's expensive and the
data items to be encoded are already properly aligned.
However, there's no guarantee that the pointer returned from
xdr_reserve_space() will still point to the correct reserved space
in the encode buffer after one or more intervening calls to
xdr_reserve_space(). It just happens to work with the current
implementation of xdr_reserve_space().
This commit effectively reverts the optimization.
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
There's no guarantee that the pointer returned from
xdr_reserve_space() will still point to the correct reserved space
in the encode buffer after one or more intervening calls to
xdr_reserve_space(). It just happens to work with the current
implementation of xdr_reserve_space().
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Extract the code that encodes the secinfo4 union data type to
clarify the logic. The removed warning is pretty well obscured and
thus probably not terribly useful.
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
There's no guarantee that the pointer returned from
xdr_reserve_space() will still point to the correct reserved space
in the encode buffer after one or more intervening calls to
xdr_reserve_space(). It just happens to work with the current
implementation of xdr_reserve_space().
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Commit eeadcb7579 ("NFSD: Simplify READ_PLUS") replaced the use of
write_bytes_to_xdr_buf(), copying what was in nfsd4_encode_read()
at the time.
However, the current code will corrupt the encoded data if the XDR
data items that are reserved early and then poked into the XDR
buffer later happen to fall on a page boundary in the XDR encoding
buffer.
__xdr_commit_encode can shift encoded data items in the encoding
buffer so that pointers returned from xdr_reserve_space() no longer
address the same part of the encoding stream.
Fixes: eeadcb7579 ("NFSD: Simplify READ_PLUS")
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Commit eeadcb7579 ("NFSD: Simplify READ_PLUS") replaced the use of
write_bytes_to_xdr_buf(), copying what was in nfsd4_encode_read()
at the time.
However, the current code will corrupt the encoded data if the XDR
data items that are reserved early and then poked into the XDR
buffer later happen to fall on a page boundary in the XDR encoding
buffer.
__xdr_commit_encode can shift encoded data items in the encoding
buffer so that pointers returned from xdr_reserve_space() no longer
address the same part of the encoding stream.
Fixes: eeadcb7579 ("NFSD: Simplify READ_PLUS")
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Commit 28d5bc468e ("NFSD: Optimize nfsd4_encode_readv()") replaced
the use of write_bytes_to_xdr_buf() because it's expensive and the
data items to be encoded are already properly aligned.
However, the current code will corrupt the encoded data if the XDR
data items that are reserved early and then poked into the XDR
buffer later happen to fall on a page boundary in the XDR encoding
buffer.
__xdr_commit_encode can shift encoded data items in the encoding
buffer so that pointers returned from xdr_reserve_space() no longer
address the same part of the encoding stream.
This isn't an issue for splice reads because the reserved encode
buffer areas must fall in the XDR buffers header for the splice to
work without error. For vectored reads, however, there is a
possibility of send buffer corruption in rare cases.
Fixes: 28d5bc468e ("NFSD: Optimize nfsd4_encode_readv()")
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
J. David reports an odd corruption of a READDIR reply sent to a
FreeBSD client.
xdr_reserve_space() has to do a special trick when the @nbytes value
requests more space than there is in the current page of the XDR
buffer.
In that case, xdr_reserve_space() returns a pointer to the start of
the next page, and then the next call to xdr_reserve_space() invokes
__xdr_commit_encode() to copy enough of the data item back into the
previous page to make that data item contiguous across the page
boundary.
But we need to be careful in the case where buffer space is reserved
early for a data item whose value will be inserted into the buffer
later.
One such caller, nfsd4_encode_operation(), reserves 8 bytes in the
encoding buffer for each COMPOUND operation. However, a READDIR
result can sometimes encode file names so that there are only 4
bytes left at the end of the current XDR buffer page (though plenty
of pages are left to handle the remaining encoding tasks).
If a COMPOUND operation follows the READDIR result (say, a GETATTR),
then nfsd4_encode_operation() will reserve 8 bytes for the op number
(9) and the op status (usually NFS4_OK). In this weird case,
xdr_reserve_space() returns a pointer to byte zero of the next buffer
page, as it assumes the data item will be copied back into place (in
the previous page) on the next call to xdr_reserve_space().
nfsd4_encode_operation() writes the op num into the buffer, then
saves the next 4-byte location for the op's status code. The next
xdr_reserve_space() call is part of GETATTR encoding, so the op num
gets copied back into the previous page, but the saved location for
the op status continues to point to the wrong spot in the current
XDR buffer page because __xdr_commit_encode() moved that data item.
After GETATTR encoding is complete, nfsd4_encode_operation() writes
the op status over the first XDR data item in the GETATTR result.
The NFS4_OK status code (0) makes it look like there are zero items
in the GETATTR's attribute bitmask.
The patch description of commit 2825a7f907 ("nfsd4: allow encoding
across page boundaries") [2014] remarks that NFSD "can't handle a
new operation starting close to the end of a page." This bug appears
to be one reason for that remark.
Reported-by: J David <j.david.lists@gmail.com>
Closes: https://lore.kernel.org/linux-nfs/3998d739-c042-46b4-8166-dbd6c5f0e804@oracle.com/T/#t
Tested-by: Rick Macklem <rmacklem@uoguelph.ca>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
In some cases, when password2 becomes the working password, the
client swaps the two password fields in the root session struct, but
not in the smb3_fs_context struct in cifs_sb. DFS automounts inherit
fs context from their parent mounts. Therefore, they might end up
getting the passwords in the stale order.
The automount should succeed, because the mount function will end up
retrying with the actual password anyway. But to reduce these
unnecessary session setup retries for automounts, we can sync the
parent context's passwords with the root session's passwords before
duplicating it to the child's fs context.
Cc: stable@vger.kernel.org
Signed-off-by: Meetakshi Setiya <msetiya@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull vfs fixes from Christian Brauner:
"afs:
- Fix the maximum cell name length
- Fix merge preference rule failure condition
fuse:
- Fix fuse_get_user_pages() so it doesn't risk misleading the caller
to think pages have been allocated when they actually haven't
- Fix direct-io folio offset and length calculation
netfs:
- Fix async direct-io handling
- Fix read-retry for filesystems that don't provide a
->prepare_read() method
vfs:
- Prevent truncating 64-bit offsets to 32-bits in iomap
- Fix memory barrier interactions when polling
- Remove MNT_ONRB to fix concurrent modification of @mnt->mnt_flags
leading to MNT_ONRB to not be raised and invalid access to a list
member"
* tag 'vfs-6.13-rc7.fixes.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
poll: kill poll_does_not_wait()
sock_poll_wait: kill the no longer necessary barrier after poll_wait()
io_uring_poll: kill the no longer necessary barrier after poll_wait()
poll_wait: kill the obsolete wait_address check
poll_wait: add mb() to fix theoretical race between waitqueue_active() and .poll()
afs: Fix merge preference rule failure condition
netfs: Fix read-retry for fs with no ->prepare_read()
netfs: Fix kernel async DIO
fs: kill MNT_ONRB
iomap: avoid avoid truncating 64-bit offset to 32 bits
afs: Fix the maximum cell name length
fuse: Set *nbytesp=0 in fuse_get_user_pages on allocation failure
fuse: fix direct io folio offset and length calculation
Pull xfs fixes from Carlos Maiolino:
- Fix a missing lock while detaching a dquot buffer
- Fix failure on xfs_update_last_rtgroup_size for !XFS_RT
* tag 'xfs-fixes-6.13-rc7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: lock dquot buffer before detaching dquot from b_li_list
xfs: don't return an error from xfs_update_last_rtgroup_size for !XFS_RT
In psz_init_zones, if the requested area has a total_size less than
record_size, kcalloc will be called with c == 0 and will return
ZERO_SIZE_PTR.
Further, this will lead to an oops.
With this patch, in this scenario, it will look like this :
[ 6.865545] pstore_zone: total size : 28672 Bytes
[ 6.865547] pstore_zone: kmsg size : 65536 Bytes
[ 6.865549] pstore_zone: pmsg size : 0 Bytes
[ 6.865551] pstore_zone: console size : 0 Bytes
[ 6.865553] pstore_zone: ftrace size : 0 Bytes
[ 6.872095] pstore_zone: zone dmesg total_size too small
[ 6.878234] pstore_zone: alloc zones failed
Signed-off-by: Eugen Hristev <eugen.hristev@linaro.org>
Link: https://lore.kernel.org/r/20250110125714.2594719-1-eugen.hristev@linaro.org
Signed-off-by: Kees Cook <kees@kernel.org>
Add some checks for the validity of the cell name. It's may get put into a
symlink, so preclude it containing any slashes or "..". Also disallow
starting/ending with a dot. This makes /afs/@cell/ as a symlink less of a
security risk.
Also disallow multiple setting of /proc/net/afs/rootcell for any given
network namespace. Once set, the value may not be changed. This makes it
easier to only create /afs/@cell and /afs/.@cell if there's a rootcell.
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20250107183454.608451-3-dhowells@redhat.com
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
We have to lock the buffer before we can delete the dquot log item from
the buffer's log item list.
Cc: stable@vger.kernel.org # v6.13-rc3
Fixes: acc8f8628c ("xfs: attach dquot buffer to dquot log item buffer")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
check_unreachable_inodes does work in online mode, with the one caveat
that it assumes check_dirents has also run - and check_dirents is not
PASS_ONLINE yet.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Factor out a version of bch2_btree_pos_to_text() that doesn't take a
pointer to a in-memory btree node, to be used for btree node scrub.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
