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6 commits

Author SHA1 Message Date
Ksawlii
cdd2f8b719 Revert "VMCI: Fix use-after-free when removing resource in vmci_resource_remove()"
This reverts commit 7cfe24a873.
2024-11-24 00:23:37 +01:00
David Fernandez Gonzalez
7cfe24a873 VMCI: Fix use-after-free when removing resource in vmci_resource_remove()
commit 48b9a8dabcc3cf5f961b2ebcd8933bf9204babb7 upstream.

When removing a resource from vmci_resource_table in
vmci_resource_remove(), the search is performed using the resource
handle by comparing context and resource fields.

It is possible though to create two resources with different types
but same handle (same context and resource fields).

When trying to remove one of the resources, vmci_resource_remove()
may not remove the intended one, but the object will still be freed
as in the case of the datagram type in vmci_datagram_destroy_handle().
vmci_resource_table will still hold a pointer to this freed resource
leading to a use-after-free vulnerability.

BUG: KASAN: use-after-free in vmci_handle_is_equal include/linux/vmw_vmci_defs.h:142 [inline]
BUG: KASAN: use-after-free in vmci_resource_remove+0x3a1/0x410 drivers/misc/vmw_vmci/vmci_resource.c:147
Read of size 4 at addr ffff88801c16d800 by task syz-executor197/1592
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x82/0xa9 lib/dump_stack.c:106
 print_address_description.constprop.0+0x21/0x366 mm/kasan/report.c:239
 __kasan_report.cold+0x7f/0x132 mm/kasan/report.c:425
 kasan_report+0x38/0x51 mm/kasan/report.c:442
 vmci_handle_is_equal include/linux/vmw_vmci_defs.h:142 [inline]
 vmci_resource_remove+0x3a1/0x410 drivers/misc/vmw_vmci/vmci_resource.c:147
 vmci_qp_broker_detach+0x89a/0x11b9 drivers/misc/vmw_vmci/vmci_queue_pair.c:2182
 ctx_free_ctx+0x473/0xbe1 drivers/misc/vmw_vmci/vmci_context.c:444
 kref_put include/linux/kref.h:65 [inline]
 vmci_ctx_put drivers/misc/vmw_vmci/vmci_context.c:497 [inline]
 vmci_ctx_destroy+0x170/0x1d6 drivers/misc/vmw_vmci/vmci_context.c:195
 vmci_host_close+0x125/0x1ac drivers/misc/vmw_vmci/vmci_host.c:143
 __fput+0x261/0xa34 fs/file_table.c:282
 task_work_run+0xf0/0x194 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x184/0x189 kernel/entry/common.c:187
 exit_to_user_mode_prepare+0x11b/0x123 kernel/entry/common.c:220
 __syscall_exit_to_user_mode_work kernel/entry/common.c:302 [inline]
 syscall_exit_to_user_mode+0x18/0x42 kernel/entry/common.c:313
 do_syscall_64+0x41/0x85 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x6e/0x0

This change ensures the type is also checked when removing
the resource from vmci_resource_table in vmci_resource_remove().

Fixes: bc63dedb7d46 ("VMCI: resource object implementation.")
Cc: stable@vger.kernel.org
Reported-by: George Kennedy <george.kennedy@oracle.com>
Signed-off-by: David Fernandez Gonzalez <david.fernandez.gonzalez@oracle.com>
Link: https://lore.kernel.org/r/20240828154338.754746-1-david.fernandez.gonzalez@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-23 23:21:07 +01:00
Hagar Gamal Halim Hemdan
140bbed30a vmci: prevent speculation leaks by sanitizing event in event_deliver()
commit 8003f00d895310d409b2bf9ef907c56b42a4e0f4 upstream.

Coverity spotted that event_msg is controlled by user-space,
event_msg->event_data.event is passed to event_deliver() and used
as an index without sanitization.

This change ensures that the event index is sanitized to mitigate any
possibility of speculative information leaks.

This bug was discovered and resolved using Coverity Static Analysis
Security Testing (SAST) by Synopsys, Inc.

Only compile tested, no access to HW.

Fixes: 1d990201f9bb ("VMCI: event handling implementation.")
Cc: stable <stable@kernel.org>
Signed-off-by: Hagar Gamal Halim Hemdan <hagarhem@amazon.com>
Link: https://lore.kernel.org/stable/20231127193533.46174-1-hagarhem%40amazon.com
Link: https://lore.kernel.org/r/20240430085916.4753-1-hagarhem@amazon.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 14:19:04 +01:00
Vasiliy Kovalev
d63c928098 VMCI: Fix possible memcpy() run-time warning in vmci_datagram_invoke_guest_handler()
commit e606e4b71798cc1df20e987dde2468e9527bd376 upstream.

The changes are similar to those given in the commit 19b070fefd0d
("VMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()").

Fix filling of the msg and msg_payload in dg_info struct, which prevents a
possible "detected field-spanning write" of memcpy warning that is issued
by the tracking mechanism __fortify_memcpy_chk.

Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org>
Link: https://lore.kernel.org/r/20240219105315.76955-1-kovalev@altlinux.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-19 09:23:15 +01:00
Harshit Mogalapalli
d0bff83a60 VMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()
[ Upstream commit 19b070fefd0d024af3daa7329cbc0d00de5302ec ]

Syzkaller hit 'WARNING in dg_dispatch_as_host' bug.

memcpy: detected field-spanning write (size 56) of single field "&dg_info->msg"
at drivers/misc/vmw_vmci/vmci_datagram.c:237 (size 24)

WARNING: CPU: 0 PID: 1555 at drivers/misc/vmw_vmci/vmci_datagram.c:237
dg_dispatch_as_host+0x88e/0xa60 drivers/misc/vmw_vmci/vmci_datagram.c:237

Some code commentry, based on my understanding:

544 #define VMCI_DG_SIZE(_dg) (VMCI_DG_HEADERSIZE + (size_t)(_dg)->payload_size)
/// This is 24 + payload_size

memcpy(&dg_info->msg, dg, dg_size);
	Destination = dg_info->msg ---> this is a 24 byte
					structure(struct vmci_datagram)
	Source = dg --> this is a 24 byte structure (struct vmci_datagram)
	Size = dg_size = 24 + payload_size

{payload_size = 56-24 =32} -- Syzkaller managed to set payload_size to 32.

 35 struct delayed_datagram_info {
 36         struct datagram_entry *entry;
 37         struct work_struct work;
 38         bool in_dg_host_queue;
 39         /* msg and msg_payload must be together. */
 40         struct vmci_datagram msg;
 41         u8 msg_payload[];
 42 };

So those extra bytes of payload are copied into msg_payload[], a run time
warning is seen while fuzzing with Syzkaller.

One possible way to fix the warning is to split the memcpy() into
two parts -- one -- direct assignment of msg and second taking care of payload.

Gustavo quoted:
"Under FORTIFY_SOURCE we should not copy data across multiple members
in a structure."

Reported-by: syzkaller <syzkaller@googlegroups.com>
Suggested-by: Vegard Nossum <vegard.nossum@oracle.com>
Suggested-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/20240105164001.2129796-2-harshit.m.mogalapalli@oracle.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 09:23:11 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00