<feed xmlns='http://www.w3.org/2005/Atom'>
<title>BMC/Intel-BMC/linux.git/fs, branch dev-5.15-intel</title>
<subtitle>Intel OpenBMC Linux kernel source tree (mirror)</subtitle>
<id>https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-5.15-intel</id>
<link rel='self' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-5.15-intel'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/'/>
<updated>2022-05-12T14:46:40+00:00</updated>
<entry>
<title>Merge commit '49caedb668e476c100d727f2174724e0610a2b92' of https://github.com/openbmc/linux into openbmc/dev-5.15-intel-bump_v5.15.36</title>
<updated>2022-05-12T14:46:40+00:00</updated>
<author>
<name>Sujoy Ray</name>
<email>sujoy.ray@intel.com</email>
</author>
<published>2022-05-04T18:01:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=efe6d9649b1d6b85b50cef64745df2e6749a8a45'/>
<id>urn:sha1:efe6d9649b1d6b85b50cef64745df2e6749a8a45</id>
<content type='text'>
Signed-off-by: Sujoy Ray &lt;sujoy.ray@intel.com&gt;
</content>
</entry>
<entry>
<title>jbd2: fix a potential race while discarding reserved buffers after an abort</title>
<updated>2022-04-27T12:39:02+00:00</updated>
<author>
<name>Ye Bin</name>
<email>yebin10@huawei.com</email>
</author>
<published>2022-03-17T14:21:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=b1b8f39c2475a1df597e6d1970e25bd64c89d774'/>
<id>urn:sha1:b1b8f39c2475a1df597e6d1970e25bd64c89d774</id>
<content type='text'>
commit 23e3d7f7061f8682c751c46512718f47580ad8f0 upstream.

we got issue as follows:
[   72.796117] EXT4-fs error (device sda): ext4_journal_check_start:83: comm fallocate: Detected aborted journal
[   72.826847] EXT4-fs (sda): Remounting filesystem read-only
fallocate: fallocate failed: Read-only file system
[   74.791830] jbd2_journal_commit_transaction: jh=0xffff9cfefe725d90 bh=0x0000000000000000 end delay
[   74.793597] ------------[ cut here ]------------
[   74.794203] kernel BUG at fs/jbd2/transaction.c:2063!
[   74.794886] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[   74.795533] CPU: 4 PID: 2260 Comm: jbd2/sda-8 Not tainted 5.17.0-rc8-next-20220315-dirty #150
[   74.798327] RIP: 0010:__jbd2_journal_unfile_buffer+0x3e/0x60
[   74.801971] RSP: 0018:ffffa828c24a3cb8 EFLAGS: 00010202
[   74.802694] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   74.803601] RDX: 0000000000000001 RSI: ffff9cfefe725d90 RDI: ffff9cfefe725d90
[   74.804554] RBP: ffff9cfefe725d90 R08: 0000000000000000 R09: ffffa828c24a3b20
[   74.805471] R10: 0000000000000001 R11: 0000000000000001 R12: ffff9cfefe725d90
[   74.806385] R13: ffff9cfefe725d98 R14: 0000000000000000 R15: ffff9cfe833a4d00
[   74.807301] FS:  0000000000000000(0000) GS:ffff9d01afb00000(0000) knlGS:0000000000000000
[   74.808338] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   74.809084] CR2: 00007f2b81bf4000 CR3: 0000000100056000 CR4: 00000000000006e0
[   74.810047] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   74.810981] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   74.811897] Call Trace:
[   74.812241]  &lt;TASK&gt;
[   74.812566]  __jbd2_journal_refile_buffer+0x12f/0x180
[   74.813246]  jbd2_journal_refile_buffer+0x4c/0xa0
[   74.813869]  jbd2_journal_commit_transaction.cold+0xa1/0x148
[   74.817550]  kjournald2+0xf8/0x3e0
[   74.819056]  kthread+0x153/0x1c0
[   74.819963]  ret_from_fork+0x22/0x30

Above issue may happen as follows:
        write                   truncate                   kjournald2
generic_perform_write
 ext4_write_begin
  ext4_walk_page_buffers
   do_journal_get_write_access -&gt;add BJ_Reserved list
 ext4_journalled_write_end
  ext4_walk_page_buffers
   write_end_fn
    ext4_handle_dirty_metadata
                ***************JBD2 ABORT**************
     jbd2_journal_dirty_metadata
 -&gt; return -EROFS, jh in reserved_list
                                                   jbd2_journal_commit_transaction
                                                    while (commit_transaction-&gt;t_reserved_list)
                                                      jh = commit_transaction-&gt;t_reserved_list;
                        truncate_pagecache_range
                         do_invalidatepage
			  ext4_journalled_invalidatepage
			   jbd2_journal_invalidatepage
			    journal_unmap_buffer
			     __dispose_buffer
			      __jbd2_journal_unfile_buffer
			       jbd2_journal_put_journal_head -&gt;put last ref_count
			        __journal_remove_journal_head
				 bh-&gt;b_private = NULL;
				 jh-&gt;b_bh = NULL;
				                      jbd2_journal_refile_buffer(journal, jh);
							bh = jh2bh(jh);
							-&gt;bh is NULL, later will trigger null-ptr-deref
				 journal_free_journal_head(jh);

After commit 96f1e0974575, we no longer hold the j_state_lock while
iterating over the list of reserved handles in
jbd2_journal_commit_transaction().  This potentially allows the
journal_head to be freed by journal_unmap_buffer while the commit
codepath is also trying to free the BJ_Reserved buffers.  Keeping
j_state_lock held while trying extends hold time of the lock
minimally, and solves this issue.

Fixes: 96f1e0974575("jbd2: avoid long hold times of j_state_lock while committing a transaction")
Signed-off-by: Ye Bin &lt;yebin10@huawei.com&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt;
Link: https://lore.kernel.org/r/20220317142137.1821590-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ext4: force overhead calculation if the s_overhead_cluster makes no sense</title>
<updated>2022-04-27T12:39:01+00:00</updated>
<author>
<name>Theodore Ts'o</name>
<email>tytso@mit.edu</email>
</author>
<published>2022-04-15T01:57:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=2b273d1fd18ebebdc5e99139f0c89b142d40ea9c'/>
<id>urn:sha1:2b273d1fd18ebebdc5e99139f0c89b142d40ea9c</id>
<content type='text'>
commit 85d825dbf4899a69407338bae462a59aa9a37326 upstream.

If the file system does not use bigalloc, calculating the overhead is
cheap, so force the recalculation of the overhead so we don't have to
trust the precalculated overhead in the superblock.

Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ext4: fix overhead calculation to account for the reserved gdt blocks</title>
<updated>2022-04-27T12:39:01+00:00</updated>
<author>
<name>Theodore Ts'o</name>
<email>tytso@mit.edu</email>
</author>
<published>2022-04-15T01:31:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=52ca84a3edd1914e575450bcd1ce6cbc6e15e2cb'/>
<id>urn:sha1:52ca84a3edd1914e575450bcd1ce6cbc6e15e2cb</id>
<content type='text'>
commit 10b01ee92df52c8d7200afead4d5e5f55a5c58b1 upstream.

The kernel calculation was underestimating the overhead by not taking
into account the reserved gdt blocks.  With this change, the overhead
calculated by the kernel matches the overhead calculation in mke2fs.

Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ext4: limit length to bitmap_maxbytes - blocksize in punch_hole</title>
<updated>2022-04-27T12:39:01+00:00</updated>
<author>
<name>Tadeusz Struk</name>
<email>tadeusz.struk@linaro.org</email>
</author>
<published>2022-03-31T20:05:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=9b90003771e5112e73d362ba4f4df03c7064ddc9'/>
<id>urn:sha1:9b90003771e5112e73d362ba4f4df03c7064ddc9</id>
<content type='text'>
commit 2da376228a2427501feb9d15815a45dbdbdd753e upstream.

Syzbot found an issue [1] in ext4_fallocate().
The C reproducer [2] calls fallocate(), passing size 0xffeffeff000ul,
and offset 0x1000000ul, which, when added together exceed the
bitmap_maxbytes for the inode. This triggers a BUG in
ext4_ind_remove_space(). According to the comments in this function
the 'end' parameter needs to be one block after the last block to be
removed. In the case when the BUG is triggered it points to the last
block. Modify the ext4_punch_hole() function and add constraint that
caps the length to satisfy the one before laster block requirement.

LINK: [1] https://syzkaller.appspot.com/bug?id=b80bd9cf348aac724a4f4dff251800106d721331
LINK: [2] https://syzkaller.appspot.com/text?tag=ReproC&amp;x=14ba0238700000

Fixes: a4bb6b64e39a ("ext4: enable "punch hole" functionality")
Reported-by: syzbot+7a806094edd5d07ba029@syzkaller.appspotmail.com
Signed-off-by: Tadeusz Struk &lt;tadeusz.struk@linaro.org&gt;
Link: https://lore.kernel.org/r/20220331200515.153214-1-tadeusz.struk@linaro.org
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ext4: fix use-after-free in ext4_search_dir</title>
<updated>2022-04-27T12:39:01+00:00</updated>
<author>
<name>Ye Bin</name>
<email>yebin10@huawei.com</email>
</author>
<published>2022-03-24T06:48:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=e3912775b4766a81cc80279ccb3740d514926ad0'/>
<id>urn:sha1:e3912775b4766a81cc80279ccb3740d514926ad0</id>
<content type='text'>
commit c186f0887fe7061a35cebef024550ec33ef8fbd8 upstream.

We got issue as follows:
EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue
==================================================================
BUG: KASAN: use-after-free in ext4_search_dir fs/ext4/namei.c:1394 [inline]
BUG: KASAN: use-after-free in search_dirblock fs/ext4/namei.c:1199 [inline]
BUG: KASAN: use-after-free in __ext4_find_entry+0xdca/0x1210 fs/ext4/namei.c:1553
Read of size 1 at addr ffff8881317c3005 by task syz-executor117/2331

CPU: 1 PID: 2331 Comm: syz-executor117 Not tainted 5.10.0+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:83 [inline]
 dump_stack+0x144/0x187 lib/dump_stack.c:124
 print_address_description+0x7d/0x630 mm/kasan/report.c:387
 __kasan_report+0x132/0x190 mm/kasan/report.c:547
 kasan_report+0x47/0x60 mm/kasan/report.c:564
 ext4_search_dir fs/ext4/namei.c:1394 [inline]
 search_dirblock fs/ext4/namei.c:1199 [inline]
 __ext4_find_entry+0xdca/0x1210 fs/ext4/namei.c:1553
 ext4_lookup_entry fs/ext4/namei.c:1622 [inline]
 ext4_lookup+0xb8/0x3a0 fs/ext4/namei.c:1690
 __lookup_hash+0xc5/0x190 fs/namei.c:1451
 do_rmdir+0x19e/0x310 fs/namei.c:3760
 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x445e59
Code: 4d c7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 &lt;48&gt; 3d 01 f0 ff ff 0f 83 1b c7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff2277fac8 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 0000000000400280 RCX: 0000000000445e59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000002
R10: 00007fff2277f990 R11: 0000000000000246 R12: 0000000000000000
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:0000000048cd3304 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x1317c3
flags: 0x200000000000000()
raw: 0200000000000000 ffffea0004526588 ffffea0004528088 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881317c2f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881317c2f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
&gt;ffff8881317c3000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff8881317c3080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881317c3100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

ext4_search_dir:
  ...
  de = (struct ext4_dir_entry_2 *)search_buf;
  dlimit = search_buf + buf_size;
  while ((char *) de &lt; dlimit) {
  ...
    if ((char *) de + de-&gt;name_len &lt;= dlimit &amp;&amp;
	 ext4_match(dir, fname, de)) {
	    ...
    }
  ...
    de_len = ext4_rec_len_from_disk(de-&gt;rec_len, dir-&gt;i_sb-&gt;s_blocksize);
    if (de_len &lt;= 0)
      return -1;
    offset += de_len;
    de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
  }

Assume:
de=0xffff8881317c2fff
dlimit=0x0xffff8881317c3000

If read 'de-&gt;name_len' which address is 0xffff8881317c3005, obviously is
out of range, then will trigger use-after-free.
To solve this issue, 'dlimit' must reserve 8 bytes, as we will read
'de-&gt;name_len' to judge if '(char *) de + de-&gt;name_len' out of range.

Signed-off-by: Ye Bin &lt;yebin10@huawei.com&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt;
Link: https://lore.kernel.org/r/20220324064816.1209985-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ext4: fix symlink file size not match to file content</title>
<updated>2022-04-27T12:39:01+00:00</updated>
<author>
<name>Ye Bin</name>
<email>yebin10@huawei.com</email>
</author>
<published>2022-03-21T14:44:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=8bb5676b49d3a44c4aed121dd3378f4d95da8e55'/>
<id>urn:sha1:8bb5676b49d3a44c4aed121dd3378f4d95da8e55</id>
<content type='text'>
commit a2b0b205d125f27cddfb4f7280e39affdaf46686 upstream.

We got issue as follows:
[home]# fsck.ext4  -fn  ram0yb
e2fsck 1.45.6 (20-Mar-2020)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Symlink /p3/d14/d1a/l3d (inode #3494) is invalid.
Clear? no
Entry 'l3d' in /p3/d14/d1a (3383) has an incorrect filetype (was 7, should be 0).
Fix? no

As the symlink file size does not match the file content. If the writeback
of the symlink data block failed, ext4_finish_bio() handles the end of IO.
However this function fails to mark the buffer with BH_write_io_error and
so when unmount does journal checkpoint it cannot detect the writeback
error and will cleanup the journal. Thus we've lost the correct data in the
journal area. To solve this issue, mark the buffer as BH_write_io_error in
ext4_finish_bio().

Cc: stable@kernel.org
Signed-off-by: Ye Bin &lt;yebin10@huawei.com&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt;
Link: https://lore.kernel.org/r/20220321144438.201685-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ext4: fix fallocate to use file_modified to update permissions consistently</title>
<updated>2022-04-27T12:39:01+00:00</updated>
<author>
<name>Darrick J. Wong</name>
<email>djwong@kernel.org</email>
</author>
<published>2022-03-08T18:50:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=ba50ea456f49f401ddea107ca9bae5d4d2ec0234'/>
<id>urn:sha1:ba50ea456f49f401ddea107ca9bae5d4d2ec0234</id>
<content type='text'>
commit ad5cd4f4ee4d5fcdb1bfb7a0c073072961e70783 upstream.

Since the initial introduction of (posix) fallocate back at the turn of
the century, it has been possible to use this syscall to change the
user-visible contents of files.  This can happen by extending the file
size during a preallocation, or through any of the newer modes (punch,
zero, collapse, insert range).  Because the call can be used to change
file contents, we should treat it like we do any other modification to a
file -- update the mtime, and drop set[ug]id privileges/capabilities.

The VFS function file_modified() does all this for us if pass it a
locked inode, so let's make fallocate drop permissions correctly.

Signed-off-by: Darrick J. Wong &lt;djwong@kernel.org&gt;
Link: https://lore.kernel.org/r/20220308185043.GA117678@magnolia
Signed-off-by: Theodore Ts'o &lt;tytso@mit.edu&gt;
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>mm, hugetlb: allow for "high" userspace addresses</title>
<updated>2022-04-27T12:38:57+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2022-04-21T23:35:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=9dcb65cdf3128113ce9a48b05a72b6f8ef2bc257'/>
<id>urn:sha1:9dcb65cdf3128113ce9a48b05a72b6f8ef2bc257</id>
<content type='text'>
commit 5f24d5a579d1eace79d505b148808a850b417d4c upstream.

This is a fix for commit f6795053dac8 ("mm: mmap: Allow for "high"
userspace addresses") for hugetlb.

This patch adds support for "high" userspace addresses that are
optionally supported on the system and have to be requested via a hint
mechanism ("high" addr parameter to mmap).

Architectures such as powerpc and x86 achieve this by making changes to
their architectural versions of hugetlb_get_unmapped_area() function.
However, arm64 uses the generic version of that function.

So take into account arch_get_mmap_base() and arch_get_mmap_end() in
hugetlb_get_unmapped_area().  To allow that, move those two macros out
of mm/mmap.c into include/linux/sched/mm.h

If these macros are not defined in architectural code then they default
to (TASK_SIZE) and (base) so should not introduce any behavioural
changes to architectures that do not define them.

For the time being, only ARM64 is affected by this change.

Catalin (ARM64) said
 "We should have fixed hugetlb_get_unmapped_area() as well when we added
  support for 52-bit VA. The reason for commit f6795053dac8 was to
  prevent normal mmap() from returning addresses above 48-bit by default
  as some user-space had hard assumptions about this.

  It's a slight ABI change if you do this for hugetlb_get_unmapped_area()
  but I doubt anyone would notice. It's more likely that the current
  behaviour would cause issues, so I'd rather have them consistent.

  Basically when arm64 gained support for 52-bit addresses we did not
  want user-space calling mmap() to suddenly get such high addresses,
  otherwise we could have inadvertently broken some programs (similar
  behaviour to x86 here). Hence we added commit f6795053dac8. But we
  missed hugetlbfs which could still get such high mmap() addresses. So
  in theory that's a potential regression that should have bee addressed
  at the same time as commit f6795053dac8 (and before arm64 enabled
  52-bit addresses)"

Link: https://lkml.kernel.org/r/ab847b6edb197bffdfe189e70fb4ac76bfe79e0d.1650033747.git.christophe.leroy@csgroup.eu
Fixes: f6795053dac8 ("mm: mmap: Allow for "high" userspace addresses")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Steve Capper &lt;steve.capper@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;	[5.0.x]
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>VFS: filename_create(): fix incorrect intent.</title>
<updated>2022-04-27T12:38:57+00:00</updated>
<author>
<name>NeilBrown</name>
<email>neilb@suse.de</email>
</author>
<published>2022-04-14T03:57:35+00:00</published>
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[ Upstream commit b3d4650d82c71b9c9a8184de9e8bb656012b289e ]

When asked to create a path ending '/', but which is not to be a
directory (LOOKUP_DIRECTORY not set), filename_create() will never try
to create the file.  If it doesn't exist, -ENOENT is reported.

However, it still passes LOOKUP_CREATE|LOOKUP_EXCL to the filesystems
-&gt;lookup() function, even though there is no intent to create.  This is
misleading and can cause incorrect behaviour.

If you try

   ln -s foo /path/dir/

where 'dir' is a directory on an NFS filesystem which is not currently
known in the dcache, this will fail with ENOENT.

But as the name is not in the dcache, nfs_lookup gets called with
LOOKUP_CREATE|LOOKUP_EXCL and so it returns NULL without performing any
lookup, with the expectation that a subsequent call to create the target
will be made, and the lookup can be combined with the creation.  In the
case with a trailing '/' and no LOOKUP_DIRECTORY, that call is never
made.  Instead filename_create() sees that the dentry is not (yet)
positive and returns -ENOENT - even though the directory actually
exists.

So only set LOOKUP_CREATE|LOOKUP_EXCL if there really is an intent to
create, and use the absence of these flags to decide if -ENOENT should
be returned.

Note that filename_parentat() is only interested in LOOKUP_REVAL, so we
split that out and store it in 'reval_flag'.  __lookup_hash() then gets
reval_flag combined with whatever create flags were determined to be
needed.

Reviewed-by: David Disseldorp &lt;ddiss@suse.de&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
Signed-off-by: NeilBrown &lt;neilb@suse.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
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