<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/fs/hfs, branch v6.1.2</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>hfs: fix OOB Read in __hfs_brec_find</title>
<updated>2022-12-31T12:32:58+00:00</updated>
<author>
<name>ZhangPeng</name>
<email>zhangpeng362@huawei.com</email>
</author>
<published>2022-11-30T06:59:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=bfc9d8f27f89717431a6aecce42ae230b437433f'/>
<id>bfc9d8f27f89717431a6aecce42ae230b437433f</id>
<content type='text'>
[ Upstream commit 8d824e69d9f3fa3121b2dda25053bae71e2460d2 ]

Syzbot reported a OOB read bug:

==================================================================
BUG: KASAN: slab-out-of-bounds in hfs_strcmp+0x117/0x190
fs/hfs/string.c:84
Read of size 1 at addr ffff88807eb62c4e by task kworker/u4:1/11
CPU: 1 PID: 11 Comm: kworker/u4:1 Not tainted
6.1.0-rc6-syzkaller-00308-g644e9524388a #0
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 &lt;TASK&gt;
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:284
 print_report+0x107/0x1f0 mm/kasan/report.c:395
 kasan_report+0xcd/0x100 mm/kasan/report.c:495
 hfs_strcmp+0x117/0x190 fs/hfs/string.c:84
 __hfs_brec_find+0x213/0x5c0 fs/hfs/bfind.c:75
 hfs_brec_find+0x276/0x520 fs/hfs/bfind.c:138
 hfs_write_inode+0x34c/0xb40 fs/hfs/inode.c:462
 write_inode fs/fs-writeback.c:1440 [inline]

If the input inode of hfs_write_inode() is incorrect:
struct inode
  struct hfs_inode_info
    struct hfs_cat_key
      struct hfs_name
        u8 len # len is greater than HFS_NAMELEN(31) which is the
maximum length of an HFS filename

OOB read occurred:
hfs_write_inode()
  hfs_brec_find()
    __hfs_brec_find()
      hfs_cat_keycmp()
        hfs_strcmp() # OOB read occurred due to len is too large

Fix this by adding a Check on len in hfs_write_inode() before calling
hfs_brec_find().

Link: https://lkml.kernel.org/r/20221130065959.2168236-1-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng &lt;zhangpeng362@huawei.com&gt;
Reported-by: &lt;syzbot+e836ff7133ac02be825f@syzkaller.appspotmail.com&gt;
Cc: Damien Le Moal &lt;damien.lemoal@opensource.wdc.com&gt;
Cc: Ira Weiny &lt;ira.weiny@intel.com&gt;
Cc: Jeff Layton &lt;jlayton@kernel.org&gt;
Cc: Kefeng Wang &lt;wangkefeng.wang@huawei.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Nanyong Sun &lt;sunnanyong@huawei.com&gt;
Cc: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 8d824e69d9f3fa3121b2dda25053bae71e2460d2 ]

Syzbot reported a OOB read bug:

==================================================================
BUG: KASAN: slab-out-of-bounds in hfs_strcmp+0x117/0x190
fs/hfs/string.c:84
Read of size 1 at addr ffff88807eb62c4e by task kworker/u4:1/11
CPU: 1 PID: 11 Comm: kworker/u4:1 Not tainted
6.1.0-rc6-syzkaller-00308-g644e9524388a #0
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 &lt;TASK&gt;
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:284
 print_report+0x107/0x1f0 mm/kasan/report.c:395
 kasan_report+0xcd/0x100 mm/kasan/report.c:495
 hfs_strcmp+0x117/0x190 fs/hfs/string.c:84
 __hfs_brec_find+0x213/0x5c0 fs/hfs/bfind.c:75
 hfs_brec_find+0x276/0x520 fs/hfs/bfind.c:138
 hfs_write_inode+0x34c/0xb40 fs/hfs/inode.c:462
 write_inode fs/fs-writeback.c:1440 [inline]

If the input inode of hfs_write_inode() is incorrect:
struct inode
  struct hfs_inode_info
    struct hfs_cat_key
      struct hfs_name
        u8 len # len is greater than HFS_NAMELEN(31) which is the
maximum length of an HFS filename

OOB read occurred:
hfs_write_inode()
  hfs_brec_find()
    __hfs_brec_find()
      hfs_cat_keycmp()
        hfs_strcmp() # OOB read occurred due to len is too large

Fix this by adding a Check on len in hfs_write_inode() before calling
hfs_brec_find().

Link: https://lkml.kernel.org/r/20221130065959.2168236-1-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng &lt;zhangpeng362@huawei.com&gt;
Reported-by: &lt;syzbot+e836ff7133ac02be825f@syzkaller.appspotmail.com&gt;
Cc: Damien Le Moal &lt;damien.lemoal@opensource.wdc.com&gt;
Cc: Ira Weiny &lt;ira.weiny@intel.com&gt;
Cc: Jeff Layton &lt;jlayton@kernel.org&gt;
Cc: Kefeng Wang &lt;wangkefeng.wang@huawei.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Nanyong Sun &lt;sunnanyong@huawei.com&gt;
Cc: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hfs: Fix OOB Write in hfs_asc2mac</title>
<updated>2022-12-31T12:32:00+00:00</updated>
<author>
<name>ZhangPeng</name>
<email>zhangpeng362@huawei.com</email>
</author>
<published>2022-12-02T03:00:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=88579c158e026860c61c4192531e8bc42f4bc642'/>
<id>88579c158e026860c61c4192531e8bc42f4bc642</id>
<content type='text'>
[ Upstream commit c53ed55cb275344086e32a7080a6b19cb183650b ]

Syzbot reported a OOB Write bug:

loop0: detected capacity change from 0 to 64
==================================================================
BUG: KASAN: slab-out-of-bounds in hfs_asc2mac+0x467/0x9a0
fs/hfs/trans.c:133
Write of size 1 at addr ffff88801848314e by task syz-executor391/3632

Call Trace:
 &lt;TASK&gt;
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:284
 print_report+0x107/0x1f0 mm/kasan/report.c:395
 kasan_report+0xcd/0x100 mm/kasan/report.c:495
 hfs_asc2mac+0x467/0x9a0 fs/hfs/trans.c:133
 hfs_cat_build_key+0x92/0x170 fs/hfs/catalog.c:28
 hfs_lookup+0x1ab/0x2c0 fs/hfs/dir.c:31
 lookup_open fs/namei.c:3391 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x10e6/0x2df0 fs/namei.c:3710
 do_filp_open+0x264/0x4f0 fs/namei.c:3740

If in-&gt;len is much larger than HFS_NAMELEN(31) which is the maximum
length of an HFS filename, a OOB write could occur in hfs_asc2mac(). In
that case, when the dst reaches the boundary, the srclen is still
greater than 0, which causes a OOB write.
Fix this by adding a check on dstlen in while() before writing to dst
address.

Link: https://lkml.kernel.org/r/20221202030038.1391945-1-zhangpeng362@huawei.com
Fixes: 328b92278650 ("[PATCH] hfs: NLS support")
Signed-off-by: ZhangPeng &lt;zhangpeng362@huawei.com&gt;
Reviewed-by: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Reported-by: &lt;syzbot+dc3b1cf9111ab5fe98e7@syzkaller.appspotmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c53ed55cb275344086e32a7080a6b19cb183650b ]

Syzbot reported a OOB Write bug:

loop0: detected capacity change from 0 to 64
==================================================================
BUG: KASAN: slab-out-of-bounds in hfs_asc2mac+0x467/0x9a0
fs/hfs/trans.c:133
Write of size 1 at addr ffff88801848314e by task syz-executor391/3632

Call Trace:
 &lt;TASK&gt;
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:284
 print_report+0x107/0x1f0 mm/kasan/report.c:395
 kasan_report+0xcd/0x100 mm/kasan/report.c:495
 hfs_asc2mac+0x467/0x9a0 fs/hfs/trans.c:133
 hfs_cat_build_key+0x92/0x170 fs/hfs/catalog.c:28
 hfs_lookup+0x1ab/0x2c0 fs/hfs/dir.c:31
 lookup_open fs/namei.c:3391 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x10e6/0x2df0 fs/namei.c:3710
 do_filp_open+0x264/0x4f0 fs/namei.c:3740

If in-&gt;len is much larger than HFS_NAMELEN(31) which is the maximum
length of an HFS filename, a OOB write could occur in hfs_asc2mac(). In
that case, when the dst reaches the boundary, the srclen is still
greater than 0, which causes a OOB write.
Fix this by adding a check on dstlen in while() before writing to dst
address.

Link: https://lkml.kernel.org/r/20221202030038.1391945-1-zhangpeng362@huawei.com
Fixes: 328b92278650 ("[PATCH] hfs: NLS support")
Signed-off-by: ZhangPeng &lt;zhangpeng362@huawei.com&gt;
Reviewed-by: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Reported-by: &lt;syzbot+dc3b1cf9111ab5fe98e7@syzkaller.appspotmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hfs: replace kmap() with kmap_local_page() in btree.c</title>
<updated>2022-09-12T04:55:09+00:00</updated>
<author>
<name>Fabio M. De Francesco</name>
<email>fmdefrancesco@gmail.com</email>
</author>
<published>2022-08-21T18:04:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=21490eff121555b123f7088b935e40ee43d2c642'/>
<id>21490eff121555b123f7088b935e40ee43d2c642</id>
<content type='text'>
kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap's pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in btree.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in btree.c.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220821180400.8198-4-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco &lt;fmdefrancesco@gmail.com&gt;
Suggested-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Cc: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Cc: Damien Le Moal &lt;damien.lemoal@opensource.wdc.com&gt;
Cc: Jeff Layton &lt;jlayton@kernel.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Muchun Song &lt;songmuchun@bytedance.com&gt;
Cc: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap's pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in btree.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in btree.c.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220821180400.8198-4-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco &lt;fmdefrancesco@gmail.com&gt;
Suggested-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Cc: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Cc: Damien Le Moal &lt;damien.lemoal@opensource.wdc.com&gt;
Cc: Jeff Layton &lt;jlayton@kernel.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Muchun Song &lt;songmuchun@bytedance.com&gt;
Cc: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hfs: replace kmap() with kmap_local_page() in bnode.c</title>
<updated>2022-09-12T04:55:08+00:00</updated>
<author>
<name>Fabio M. De Francesco</name>
<email>fmdefrancesco@gmail.com</email>
</author>
<published>2022-08-21T18:03:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=ca0ac8dfd35b218b3c95d3b38c695fbff35d94ca'/>
<id>ca0ac8dfd35b218b3c95d3b38c695fbff35d94ca</id>
<content type='text'>
kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap's pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in bnode.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in bnode.c.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220821180400.8198-3-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco &lt;fmdefrancesco@gmail.com&gt;
Suggested-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Cc: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Cc: Damien Le Moal &lt;damien.lemoal@opensource.wdc.com&gt;
Cc: Jeff Layton &lt;jlayton@kernel.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Muchun Song &lt;songmuchun@bytedance.com&gt;
Cc: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
kmap() is being deprecated in favor of kmap_local_page().

Two main problems with kmap(): (1) It comes with an overhead as mapping
space is restricted and protected by a global lock for synchronization and
(2) it also requires global TLB invalidation when the kmap's pool wraps
and it might block when the mapping space is fully utilized until a slot
becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in bnode.c is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in bnode.c.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.

Link: https://lkml.kernel.org/r/20220821180400.8198-3-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco &lt;fmdefrancesco@gmail.com&gt;
Suggested-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Cc: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Cc: Damien Le Moal &lt;damien.lemoal@opensource.wdc.com&gt;
Cc: Jeff Layton &lt;jlayton@kernel.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Muchun Song &lt;songmuchun@bytedance.com&gt;
Cc: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hfs: unmap the page in the "fail_page" label</title>
<updated>2022-09-12T04:55:08+00:00</updated>
<author>
<name>Fabio M. De Francesco</name>
<email>fmdefrancesco@gmail.com</email>
</author>
<published>2022-08-21T18:03:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=d75e9a4bccf4e19928534dec797935e650f85b09'/>
<id>d75e9a4bccf4e19928534dec797935e650f85b09</id>
<content type='text'>
Patch series "hfs: Replace kmap() with kmap_local_page()".

kmap() is being deprecated in favor of kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmaps pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in fs/hfs is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in fs/hfs.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Fix a bug due to a page being not unmapped if the code jumps to the
"fail_page" label (1/3).

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.


This patch (of 3):

Several paths within hfs_btree_open() jump to the "fail_page" label where
put_page() is called while the page is still mapped.

Call kunmap() to unmap the page soon before put_page().

Link: https://lkml.kernel.org/r/20220821180400.8198-1-fmdefrancesco@gmail.com
Link: https://lkml.kernel.org/r/20220821180400.8198-2-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco &lt;fmdefrancesco@gmail.com&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Cc: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Cc: Damien Le Moal &lt;damien.lemoal@opensource.wdc.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;]
Cc: Jeff Layton &lt;jlayton@kernel.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Cc: Muchun Song &lt;songmuchun@bytedance.com&gt;
Cc: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Patch series "hfs: Replace kmap() with kmap_local_page()".

kmap() is being deprecated in favor of kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmaps pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored and still valid.

Since its use in fs/hfs is safe everywhere, it should be preferred.

Therefore, replace kmap() with kmap_local_page() in fs/hfs.  Where
possible, use the suited standard helpers (memzero_page(), memcpy_page())
instead of open coding kmap_local_page() plus memset() or memcpy().

Fix a bug due to a page being not unmapped if the code jumps to the
"fail_page" label (1/3).

Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with
HIGHMEM64GB enabled.


This patch (of 3):

Several paths within hfs_btree_open() jump to the "fail_page" label where
put_page() is called while the page is still mapped.

Call kunmap() to unmap the page soon before put_page().

Link: https://lkml.kernel.org/r/20220821180400.8198-1-fmdefrancesco@gmail.com
Link: https://lkml.kernel.org/r/20220821180400.8198-2-fmdefrancesco@gmail.com
Signed-off-by: Fabio M. De Francesco &lt;fmdefrancesco@gmail.com&gt;
Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt;
Reviewed-by: Viacheslav Dubeyko &lt;slava@dubeyko.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Cc: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Cc: Damien Le Moal &lt;damien.lemoal@opensource.wdc.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;]
Cc: Jeff Layton &lt;jlayton@kernel.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Cc: Muchun Song &lt;songmuchun@bytedance.com&gt;
Cc: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hfs: Remove check for PageError</title>
<updated>2022-06-29T12:51:06+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2022-05-17T22:12:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=c9ed489c664cf041a785c0117a21bc6d71545dde'/>
<id>c9ed489c664cf041a785c0117a21bc6d71545dde</id>
<content type='text'>
If read_mapping_page() encounters an error, it returns an errno, not a
page with PageError set, so this is dead code.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If read_mapping_page() encounters an error, it returns an errno, not a
page with PageError set, so this is dead code.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fs: Change try_to_free_buffers() to take a folio</title>
<updated>2022-05-10T03:12:34+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2022-05-01T05:08:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=68189fef88c7d02eb92e038be3d6428ebd0d2945'/>
<id>68189fef88c7d02eb92e038be3d6428ebd0d2945</id>
<content type='text'>
All but two of the callers already have a folio; pass a folio into
try_to_free_buffers().  This removes the last user of cancel_dirty_page()
so remove that wrapper function too.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
All but two of the callers already have a folio; pass a folio into
try_to_free_buffers().  This removes the last user of cancel_dirty_page()
so remove that wrapper function too.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hfs: Convert to release_folio</title>
<updated>2022-05-10T03:12:33+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2022-05-01T03:53:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=5784f09bf4dfdc76d8d68437efd01c6a0646a08e'/>
<id>5784f09bf4dfdc76d8d68437efd01c6a0646a08e</id>
<content type='text'>
Use a folio throughout hfs_release_folio().

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use a folio throughout hfs_release_folio().

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Jeff Layton &lt;jlayton@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fs: Convert block_read_full_page() to block_read_full_folio()</title>
<updated>2022-05-09T20:21:44+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2022-04-29T14:40:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=2c69e2057962b6bd76d72446453862eb59325b49'/>
<id>2c69e2057962b6bd76d72446453862eb59325b49</id>
<content type='text'>
This function is NOT converted to handle large folios, so include
an assert that the filesystem isn't passing one in.  Otherwise, use
the folio functions instead of the page functions, where they exist.
Convert all filesystems which use block_read_full_page().

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This function is NOT converted to handle large folios, so include
an assert that the filesystem isn't passing one in.  Otherwise, use
the folio functions instead of the page functions, where they exist.
Convert all filesystems which use block_read_full_page().

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hfs: Call hfs_write_begin() and generic_write_end() directly</title>
<updated>2022-05-08T18:45:56+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2022-03-03T18:43:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=cfef1f7b39a6f24555175c48c56bf1dc9fe01d4e'/>
<id>cfef1f7b39a6f24555175c48c56bf1dc9fe01d4e</id>
<content type='text'>
There is only one kind of write_begin/write_end aops, so we don't need
to look up which aop it is, just make hfs_write_begin() available to
this file and call it directly.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is only one kind of write_begin/write_end aops, so we don't need
to look up which aop it is, just make hfs_write_begin() available to
this file and call it directly.

Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
</pre>
</div>
</content>
</entry>
</feed>
