<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/fs/ecryptfs, branch linux-4.19.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ecryptfs: Fix buffer size for tag 66 packet</title>
<updated>2024-06-16T11:23:24+00:00</updated>
<author>
<name>Brian Kubisiak</name>
<email>brian@kubisiak.com</email>
</author>
<published>2024-03-17T14:46:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1c125b9287e58f364d82174efb167414b92b11f1'/>
<id>1c125b9287e58f364d82174efb167414b92b11f1</id>
<content type='text'>
[ Upstream commit 85a6a1aff08ec9f5b929d345d066e2830e8818e5 ]

The 'TAG 66 Packet Format' description is missing the cipher code and
checksum fields that are packed into the message packet. As a result,
the buffer allocated for the packet is 3 bytes too small and
write_tag_66_packet() will write up to 3 bytes past the end of the
buffer.

Fix this by increasing the size of the allocation so the whole packet
will always fit in the buffer.

This fixes the below kasan slab-out-of-bounds bug:

  BUG: KASAN: slab-out-of-bounds in ecryptfs_generate_key_packet_set+0x7d6/0xde0
  Write of size 1 at addr ffff88800afbb2a5 by task touch/181

  CPU: 0 PID: 181 Comm: touch Not tainted 6.6.13-gnu #1 4c9534092be820851bb687b82d1f92a426598dc6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2/GNU Guix 04/01/2014
  Call Trace:
   &lt;TASK&gt;
   dump_stack_lvl+0x4c/0x70
   print_report+0xc5/0x610
   ? ecryptfs_generate_key_packet_set+0x7d6/0xde0
   ? kasan_complete_mode_report_info+0x44/0x210
   ? ecryptfs_generate_key_packet_set+0x7d6/0xde0
   kasan_report+0xc2/0x110
   ? ecryptfs_generate_key_packet_set+0x7d6/0xde0
   __asan_store1+0x62/0x80
   ecryptfs_generate_key_packet_set+0x7d6/0xde0
   ? __pfx_ecryptfs_generate_key_packet_set+0x10/0x10
   ? __alloc_pages+0x2e2/0x540
   ? __pfx_ovl_open+0x10/0x10 [overlay 30837f11141636a8e1793533a02e6e2e885dad1d]
   ? dentry_open+0x8f/0xd0
   ecryptfs_write_metadata+0x30a/0x550
   ? __pfx_ecryptfs_write_metadata+0x10/0x10
   ? ecryptfs_get_lower_file+0x6b/0x190
   ecryptfs_initialize_file+0x77/0x150
   ecryptfs_create+0x1c2/0x2f0
   path_openat+0x17cf/0x1ba0
   ? __pfx_path_openat+0x10/0x10
   do_filp_open+0x15e/0x290
   ? __pfx_do_filp_open+0x10/0x10
   ? __kasan_check_write+0x18/0x30
   ? _raw_spin_lock+0x86/0xf0
   ? __pfx__raw_spin_lock+0x10/0x10
   ? __kasan_check_write+0x18/0x30
   ? alloc_fd+0xf4/0x330
   do_sys_openat2+0x122/0x160
   ? __pfx_do_sys_openat2+0x10/0x10
   __x64_sys_openat+0xef/0x170
   ? __pfx___x64_sys_openat+0x10/0x10
   do_syscall_64+0x60/0xd0
   entry_SYSCALL_64_after_hwframe+0x6e/0xd8
  RIP: 0033:0x7f00a703fd67
  Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 &lt;48&gt; 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f
  RSP: 002b:00007ffc088e30b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
  RAX: ffffffffffffffda RBX: 00007ffc088e3368 RCX: 00007f00a703fd67
  RDX: 0000000000000941 RSI: 00007ffc088e48d7 RDI: 00000000ffffff9c
  RBP: 00007ffc088e48d7 R08: 0000000000000001 R09: 0000000000000000
  R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000941
  R13: 0000000000000000 R14: 00007ffc088e48d7 R15: 00007f00a7180040
   &lt;/TASK&gt;

  Allocated by task 181:
   kasan_save_stack+0x2f/0x60
   kasan_set_track+0x29/0x40
   kasan_save_alloc_info+0x25/0x40
   __kasan_kmalloc+0xc5/0xd0
   __kmalloc+0x66/0x160
   ecryptfs_generate_key_packet_set+0x6d2/0xde0
   ecryptfs_write_metadata+0x30a/0x550
   ecryptfs_initialize_file+0x77/0x150
   ecryptfs_create+0x1c2/0x2f0
   path_openat+0x17cf/0x1ba0
   do_filp_open+0x15e/0x290
   do_sys_openat2+0x122/0x160
   __x64_sys_openat+0xef/0x170
   do_syscall_64+0x60/0xd0
   entry_SYSCALL_64_after_hwframe+0x6e/0xd8

Fixes: dddfa461fc89 ("[PATCH] eCryptfs: Public key; packet management")
Signed-off-by: Brian Kubisiak &lt;brian@kubisiak.com&gt;
Link: https://lore.kernel.org/r/5j2q56p6qkhezva6b2yuqfrsurmvrrqtxxzrnp3wqu7xrz22i7@hoecdztoplbl
Signed-off-by: Christian Brauner &lt;brauner@kernel.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 85a6a1aff08ec9f5b929d345d066e2830e8818e5 ]

The 'TAG 66 Packet Format' description is missing the cipher code and
checksum fields that are packed into the message packet. As a result,
the buffer allocated for the packet is 3 bytes too small and
write_tag_66_packet() will write up to 3 bytes past the end of the
buffer.

Fix this by increasing the size of the allocation so the whole packet
will always fit in the buffer.

This fixes the below kasan slab-out-of-bounds bug:

  BUG: KASAN: slab-out-of-bounds in ecryptfs_generate_key_packet_set+0x7d6/0xde0
  Write of size 1 at addr ffff88800afbb2a5 by task touch/181

  CPU: 0 PID: 181 Comm: touch Not tainted 6.6.13-gnu #1 4c9534092be820851bb687b82d1f92a426598dc6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2/GNU Guix 04/01/2014
  Call Trace:
   &lt;TASK&gt;
   dump_stack_lvl+0x4c/0x70
   print_report+0xc5/0x610
   ? ecryptfs_generate_key_packet_set+0x7d6/0xde0
   ? kasan_complete_mode_report_info+0x44/0x210
   ? ecryptfs_generate_key_packet_set+0x7d6/0xde0
   kasan_report+0xc2/0x110
   ? ecryptfs_generate_key_packet_set+0x7d6/0xde0
   __asan_store1+0x62/0x80
   ecryptfs_generate_key_packet_set+0x7d6/0xde0
   ? __pfx_ecryptfs_generate_key_packet_set+0x10/0x10
   ? __alloc_pages+0x2e2/0x540
   ? __pfx_ovl_open+0x10/0x10 [overlay 30837f11141636a8e1793533a02e6e2e885dad1d]
   ? dentry_open+0x8f/0xd0
   ecryptfs_write_metadata+0x30a/0x550
   ? __pfx_ecryptfs_write_metadata+0x10/0x10
   ? ecryptfs_get_lower_file+0x6b/0x190
   ecryptfs_initialize_file+0x77/0x150
   ecryptfs_create+0x1c2/0x2f0
   path_openat+0x17cf/0x1ba0
   ? __pfx_path_openat+0x10/0x10
   do_filp_open+0x15e/0x290
   ? __pfx_do_filp_open+0x10/0x10
   ? __kasan_check_write+0x18/0x30
   ? _raw_spin_lock+0x86/0xf0
   ? __pfx__raw_spin_lock+0x10/0x10
   ? __kasan_check_write+0x18/0x30
   ? alloc_fd+0xf4/0x330
   do_sys_openat2+0x122/0x160
   ? __pfx_do_sys_openat2+0x10/0x10
   __x64_sys_openat+0xef/0x170
   ? __pfx___x64_sys_openat+0x10/0x10
   do_syscall_64+0x60/0xd0
   entry_SYSCALL_64_after_hwframe+0x6e/0xd8
  RIP: 0033:0x7f00a703fd67
  Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 &lt;48&gt; 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f
  RSP: 002b:00007ffc088e30b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
  RAX: ffffffffffffffda RBX: 00007ffc088e3368 RCX: 00007f00a703fd67
  RDX: 0000000000000941 RSI: 00007ffc088e48d7 RDI: 00000000ffffff9c
  RBP: 00007ffc088e48d7 R08: 0000000000000001 R09: 0000000000000000
  R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000941
  R13: 0000000000000000 R14: 00007ffc088e48d7 R15: 00007f00a7180040
   &lt;/TASK&gt;

  Allocated by task 181:
   kasan_save_stack+0x2f/0x60
   kasan_set_track+0x29/0x40
   kasan_save_alloc_info+0x25/0x40
   __kasan_kmalloc+0xc5/0xd0
   __kmalloc+0x66/0x160
   ecryptfs_generate_key_packet_set+0x6d2/0xde0
   ecryptfs_write_metadata+0x30a/0x550
   ecryptfs_initialize_file+0x77/0x150
   ecryptfs_create+0x1c2/0x2f0
   path_openat+0x17cf/0x1ba0
   do_filp_open+0x15e/0x290
   do_sys_openat2+0x122/0x160
   __x64_sys_openat+0xef/0x170
   do_syscall_64+0x60/0xd0
   entry_SYSCALL_64_after_hwframe+0x6e/0xd8

Fixes: dddfa461fc89 ("[PATCH] eCryptfs: Public key; packet management")
Signed-off-by: Brian Kubisiak &lt;brian@kubisiak.com&gt;
Link: https://lore.kernel.org/r/5j2q56p6qkhezva6b2yuqfrsurmvrrqtxxzrnp3wqu7xrz22i7@hoecdztoplbl
Signed-off-by: Christian Brauner &lt;brauner@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "ecryptfs: replace BUG_ON with error handling code"</title>
<updated>2021-05-26T09:48:34+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2021-05-03T11:57:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b3af22579552bc449ad2e68d4a5c7b5221ecf45b'/>
<id>b3af22579552bc449ad2e68d4a5c7b5221ecf45b</id>
<content type='text'>
commit e1436df2f2550bc89d832ffd456373fdf5d5b5d7 upstream.

This reverts commit 2c2a7552dd6465e8fde6bc9cccf8d66ed1c1eb72.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

The original commit log for this change was incorrect, no "error
handling code" was added, things will blow up just as badly as before if
any of these cases ever were true.  As this BUG_ON() never fired, and
most of these checks are "obviously" never going to be true, let's just
revert to the original code for now until this gets unwound to be done
correctly in the future.

Cc: Aditya Pakki &lt;pakki001@umn.edu&gt;
Fixes: 2c2a7552dd64 ("ecryptfs: replace BUG_ON with error handling code")
Cc: stable &lt;stable@vger.kernel.org&gt;
Acked-by: Tyler Hicks &lt;code@tyhicks.com&gt;
Link: https://lore.kernel.org/r/20210503115736.2104747-49-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e1436df2f2550bc89d832ffd456373fdf5d5b5d7 upstream.

This reverts commit 2c2a7552dd6465e8fde6bc9cccf8d66ed1c1eb72.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

The original commit log for this change was incorrect, no "error
handling code" was added, things will blow up just as badly as before if
any of these cases ever were true.  As this BUG_ON() never fired, and
most of these checks are "obviously" never going to be true, let's just
revert to the original code for now until this gets unwound to be done
correctly in the future.

Cc: Aditya Pakki &lt;pakki001@umn.edu&gt;
Fixes: 2c2a7552dd64 ("ecryptfs: replace BUG_ON with error handling code")
Cc: stable &lt;stable@vger.kernel.org&gt;
Acked-by: Tyler Hicks &lt;code@tyhicks.com&gt;
Link: https://lore.kernel.org/r/20210503115736.2104747-49-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ecryptfs: fix kernel panic with null dev_name</title>
<updated>2021-05-22T08:59:13+00:00</updated>
<author>
<name>Jeffrey Mitchell</name>
<email>jeffrey.mitchell@starlab.io</email>
</author>
<published>2021-02-26T21:00:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6fcdf51e9b6d694af8f2150923586a0ad8f5ec81'/>
<id>6fcdf51e9b6d694af8f2150923586a0ad8f5ec81</id>
<content type='text'>
commit 9046625511ad8dfbc8c6c2de16b3532c43d68d48 upstream.

When mounting eCryptfs, a null "dev_name" argument to ecryptfs_mount()
causes a kernel panic if the parsed options are valid. The easiest way to
reproduce this is to call mount() from userspace with an existing
eCryptfs mount's options and a "source" argument of 0.

Error out if "dev_name" is null in ecryptfs_mount()

Fixes: 237fead61998 ("[PATCH] ecryptfs: fs/Makefile and fs/Kconfig")
Cc: stable@vger.kernel.org
Signed-off-by: Jeffrey Mitchell &lt;jeffrey.mitchell@starlab.io&gt;
Signed-off-by: Tyler Hicks &lt;code@tyhicks.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9046625511ad8dfbc8c6c2de16b3532c43d68d48 upstream.

When mounting eCryptfs, a null "dev_name" argument to ecryptfs_mount()
causes a kernel panic if the parsed options are valid. The easiest way to
reproduce this is to call mount() from userspace with an existing
eCryptfs mount's options and a "source" argument of 0.

Error out if "dev_name" is null in ecryptfs_mount()

Fixes: 237fead61998 ("[PATCH] ecryptfs: fs/Makefile and fs/Kconfig")
Cc: stable@vger.kernel.org
Signed-off-by: Jeffrey Mitchell &lt;jeffrey.mitchell@starlab.io&gt;
Signed-off-by: Tyler Hicks &lt;code@tyhicks.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ecryptfs: replace BUG_ON with error handling code</title>
<updated>2020-02-28T15:38:59+00:00</updated>
<author>
<name>Aditya Pakki</name>
<email>pakki001@umn.edu</email>
</author>
<published>2020-02-14T18:21:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c0965be4b28b8078202bd174d2cf2beb1b91fe46'/>
<id>c0965be4b28b8078202bd174d2cf2beb1b91fe46</id>
<content type='text'>
commit 2c2a7552dd6465e8fde6bc9cccf8d66ed1c1eb72 upstream.

In crypt_scatterlist, if the crypt_stat argument is not set up
correctly, the kernel crashes. Instead, by returning an error code
upstream, the error is handled safely.

The issue is detected via a static analysis tool written by us.

Fixes: 237fead619984 (ecryptfs: fs/Makefile and fs/Kconfig)
Signed-off-by: Aditya Pakki &lt;pakki001@umn.edu&gt;
Signed-off-by: Tyler Hicks &lt;code@tyhicks.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2c2a7552dd6465e8fde6bc9cccf8d66ed1c1eb72 upstream.

In crypt_scatterlist, if the crypt_stat argument is not set up
correctly, the kernel crashes. Instead, by returning an error code
upstream, the error is handled safely.

The issue is detected via a static analysis tool written by us.

Fixes: 237fead619984 (ecryptfs: fs/Makefile and fs/Kconfig)
Signed-off-by: Aditya Pakki &lt;pakki001@umn.edu&gt;
Signed-off-by: Tyler Hicks &lt;code@tyhicks.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ecryptfs: fix a memory leak bug in ecryptfs_init_messaging()</title>
<updated>2020-02-28T15:38:44+00:00</updated>
<author>
<name>Wenwen Wang</name>
<email>wenwen@cs.uga.edu</email>
</author>
<published>2019-08-20T05:33:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d7a5408e4b6dc3796c9dbb0677d32fce19e715c9'/>
<id>d7a5408e4b6dc3796c9dbb0677d32fce19e715c9</id>
<content type='text'>
commit b4a81b87a4cfe2bb26a4a943b748d96a43ef20e8 upstream.

In ecryptfs_init_messaging(), if the allocation for 'ecryptfs_msg_ctx_arr'
fails, the previously allocated 'ecryptfs_daemon_hash' is not deallocated,
leading to a memory leak bug. To fix this issue, free
'ecryptfs_daemon_hash' before returning the error.

Cc: stable@vger.kernel.org
Fixes: 88b4a07e6610 ("[PATCH] eCryptfs: Public key transport mechanism")
Signed-off-by: Wenwen Wang &lt;wenwen@cs.uga.edu&gt;
Signed-off-by: Tyler Hicks &lt;tyhicks@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b4a81b87a4cfe2bb26a4a943b748d96a43ef20e8 upstream.

In ecryptfs_init_messaging(), if the allocation for 'ecryptfs_msg_ctx_arr'
fails, the previously allocated 'ecryptfs_daemon_hash' is not deallocated,
leading to a memory leak bug. To fix this issue, free
'ecryptfs_daemon_hash' before returning the error.

Cc: stable@vger.kernel.org
Fixes: 88b4a07e6610 ("[PATCH] eCryptfs: Public key transport mechanism")
Signed-off-by: Wenwen Wang &lt;wenwen@cs.uga.edu&gt;
Signed-off-by: Tyler Hicks &lt;tyhicks@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ecryptfs: fix a memory leak bug in parse_tag_1_packet()</title>
<updated>2020-02-28T15:38:44+00:00</updated>
<author>
<name>Wenwen Wang</name>
<email>wenwen@cs.uga.edu</email>
</author>
<published>2019-08-20T05:16:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=70457d99cd347de4fb8c6012757515d43b5bcf20'/>
<id>70457d99cd347de4fb8c6012757515d43b5bcf20</id>
<content type='text'>
commit fe2e082f5da5b4a0a92ae32978f81507ef37ec66 upstream.

In parse_tag_1_packet(), if tag 1 packet contains a key larger than
ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES, no cleanup is executed, leading to a
memory leak on the allocated 'auth_tok_list_item'. To fix this issue, go to
the label 'out_free' to perform the cleanup work.

Cc: stable@vger.kernel.org
Fixes: dddfa461fc89 ("[PATCH] eCryptfs: Public key; packet management")
Signed-off-by: Wenwen Wang &lt;wenwen@cs.uga.edu&gt;
Signed-off-by: Tyler Hicks &lt;tyhicks@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit fe2e082f5da5b4a0a92ae32978f81507ef37ec66 upstream.

In parse_tag_1_packet(), if tag 1 packet contains a key larger than
ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES, no cleanup is executed, leading to a
memory leak on the allocated 'auth_tok_list_item'. To fix this issue, go to
the label 'out_free' to perform the cleanup work.

Cc: stable@vger.kernel.org
Fixes: dddfa461fc89 ("[PATCH] eCryptfs: Public key; packet management")
Signed-off-by: Wenwen Wang &lt;wenwen@cs.uga.edu&gt;
Signed-off-by: Tyler Hicks &lt;tyhicks@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ecryptfs_lookup_interpose(): lower_dentry-&gt;d_parent is not stable either</title>
<updated>2019-11-20T17:45:18+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2019-11-03T18:55:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bdae2f7b2031cbeebca93267bef5e829e55c03ca'/>
<id>bdae2f7b2031cbeebca93267bef5e829e55c03ca</id>
<content type='text'>
commit 762c69685ff7ad5ad7fee0656671e20a0c9c864d upstream.

We need to get the underlying dentry of parent; sure, absent the races
it is the parent of underlying dentry, but there's nothing to prevent
losing a timeslice to preemtion in the middle of evaluation of
lower_dentry-&gt;d_parent-&gt;d_inode, having another process move lower_dentry
around and have its (ex)parent not pinned anymore and freed on memory
pressure.  Then we regain CPU and try to fetch -&gt;d_inode from memory
that is freed by that point.

dentry-&gt;d_parent *is* stable here - it's an argument of -&gt;lookup() and
we are guaranteed that it won't be moved anywhere until we feed it
to d_add/d_splice_alias.  So we safely go that way to get to its
underlying dentry.

Cc: stable@vger.kernel.org # since 2009 or so
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 762c69685ff7ad5ad7fee0656671e20a0c9c864d upstream.

We need to get the underlying dentry of parent; sure, absent the races
it is the parent of underlying dentry, but there's nothing to prevent
losing a timeslice to preemtion in the middle of evaluation of
lower_dentry-&gt;d_parent-&gt;d_inode, having another process move lower_dentry
around and have its (ex)parent not pinned anymore and freed on memory
pressure.  Then we regain CPU and try to fetch -&gt;d_inode from memory
that is freed by that point.

dentry-&gt;d_parent *is* stable here - it's an argument of -&gt;lookup() and
we are guaranteed that it won't be moved anywhere until we feed it
to d_add/d_splice_alias.  So we safely go that way to get to its
underlying dentry.

Cc: stable@vger.kernel.org # since 2009 or so
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ecryptfs_lookup_interpose(): lower_dentry-&gt;d_inode is not stable</title>
<updated>2019-11-20T17:45:18+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2019-11-03T18:45:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=beb3860c2e0edb81786fbeaeace366174b59d5ef'/>
<id>beb3860c2e0edb81786fbeaeace366174b59d5ef</id>
<content type='text'>
commit e72b9dd6a5f17d0fb51f16f8685f3004361e83d0 upstream.

lower_dentry can't go from positive to negative (we have it pinned),
but it *can* go from negative to positive.  So fetching -&gt;d_inode
into a local variable, doing a blocking allocation, checking that
now -&gt;d_inode is non-NULL and feeding the value we'd fetched
earlier to a function that won't accept NULL is not a good idea.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e72b9dd6a5f17d0fb51f16f8685f3004361e83d0 upstream.

lower_dentry can't go from positive to negative (we have it pinned),
but it *can* go from negative to positive.  So fetching -&gt;d_inode
into a local variable, doing a blocking allocation, checking that
now -&gt;d_inode is non-NULL and feeding the value we'd fetched
earlier to a function that won't accept NULL is not a good idea.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>eCryptfs: fix a couple type promotion bugs</title>
<updated>2019-07-26T07:14:29+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2018-07-04T09:35:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=30c6b34759f6522432b8b5422956070b6aa9ee81'/>
<id>30c6b34759f6522432b8b5422956070b6aa9ee81</id>
<content type='text'>
commit 0bdf8a8245fdea6f075a5fede833a5fcf1b3466c upstream.

ECRYPTFS_SIZE_AND_MARKER_BYTES is type size_t, so if "rc" is negative
that gets type promoted to a high positive value and treated as success.

Fixes: 778aeb42a708 ("eCryptfs: Cleanup and optimize ecryptfs_lookup_interpose()")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
[tyhicks: Use "if/else if" rather than "if/if"]
Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks &lt;tyhicks@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0bdf8a8245fdea6f075a5fede833a5fcf1b3466c upstream.

ECRYPTFS_SIZE_AND_MARKER_BYTES is type size_t, so if "rc" is negative
that gets type promoted to a high positive value and treated as success.

Fixes: 778aeb42a708 ("eCryptfs: Cleanup and optimize ecryptfs_lookup_interpose()")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
[tyhicks: Use "if/else if" rather than "if/if"]
Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks &lt;tyhicks@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2018-05-21T18:54:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-05-21T18:54:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5997aab0a11ea27ee8e520ecc551ed18fd3e8296'/>
<id>5997aab0a11ea27ee8e520ecc551ed18fd3e8296</id>
<content type='text'>
Pull vfs fixes from Al Viro:
 "Assorted fixes all over the place"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: fix io_destroy(2) vs. lookup_ioctx() race
  ext2: fix a block leak
  nfsd: vfs_mkdir() might succeed leaving dentry negative unhashed
  cachefiles: vfs_mkdir() might succeed leaving dentry negative unhashed
  unfuck sysfs_mount()
  kernfs: deal with kernfs_fill_super() failures
  cramfs: Fix IS_ENABLED typo
  befs_lookup(): use d_splice_alias()
  affs_lookup: switch to d_splice_alias()
  affs_lookup(): close a race with affs_remove_link()
  fix breakage caused by d_find_alias() semantics change
  fs: don't scan the inode cache before SB_BORN is set
  do d_instantiate/unlock_new_inode combinations safely
  iov_iter: fix memory leak in pipe_get_pages_alloc()
  iov_iter: fix return type of __pipe_get_pages()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull vfs fixes from Al Viro:
 "Assorted fixes all over the place"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: fix io_destroy(2) vs. lookup_ioctx() race
  ext2: fix a block leak
  nfsd: vfs_mkdir() might succeed leaving dentry negative unhashed
  cachefiles: vfs_mkdir() might succeed leaving dentry negative unhashed
  unfuck sysfs_mount()
  kernfs: deal with kernfs_fill_super() failures
  cramfs: Fix IS_ENABLED typo
  befs_lookup(): use d_splice_alias()
  affs_lookup: switch to d_splice_alias()
  affs_lookup(): close a race with affs_remove_link()
  fix breakage caused by d_find_alias() semantics change
  fs: don't scan the inode cache before SB_BORN is set
  do d_instantiate/unlock_new_inode combinations safely
  iov_iter: fix memory leak in pipe_get_pages_alloc()
  iov_iter: fix return type of __pipe_get_pages()
</pre>
</div>
</content>
</entry>
</feed>
