50 lines
1.7 KiB
Diff
50 lines
1.7 KiB
Diff
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# Commit 29bcf64ce8bc0b1b7aacd00c8668f255c4f0686c
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# Date 2015-10-29 13:31:10 +0100
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# Author Julien Grall <julien.grall@citrix.com>
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# Committer Jan Beulich <jbeulich@suse.com>
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arm: Support hypercall_create_continuation for multicall
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Multicall for ARM has been supported since commit f0dbdc6 "xen: arm: fully
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implement multicall interface.". Although, if an hypercall in multicall
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requires preemption, it will crash the host:
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(XEN) Xen BUG at domain.c:347
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(XEN) ----[ Xen-4.7-unstable arm64 debug=y Tainted: C ]----
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[...]
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(XEN) Xen call trace:
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(XEN) [<00000000002420cc>] hypercall_create_continuation+0x64/0x380 (PC)
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(XEN) [<0000000000217274>] do_memory_op+0x1b00/0x2334 (LR)
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(XEN) [<0000000000250d2c>] do_multicall_call+0x114/0x124
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(XEN) [<0000000000217ff0>] do_multicall+0x17c/0x23c
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(XEN) [<000000000024f97c>] do_trap_hypercall+0x90/0x12c
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(XEN) [<0000000000251ca8>] do_trap_hypervisor+0xd2c/0x1ba4
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(XEN) [<00000000002582cc>] guest_sync+0x88/0xb8
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(XEN)
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(XEN)
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(XEN) ****************************************
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(XEN) Panic on CPU 5:
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(XEN) Xen BUG at domain.c:347
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(XEN) ****************************************
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(XEN)
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(XEN) Manual reset required ('noreboot' specified)
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Looking to the code, the support of multicall looks valid to me, as we only
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need to fill call.args[...]. So drop the BUG();
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This is CVE-2015-7812 / XSA-145.
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Signed-off-by: Julien Grall <julien.grall@citrix.com>
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Acked-by: Ian Campbell <ian.campbell@citrix.com>
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--- a/xen/arch/arm/domain.c
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+++ b/xen/arch/arm/domain.c
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@@ -344,8 +344,6 @@ unsigned long hypercall_create_continuat
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if ( test_bit(_MCSF_in_multicall, &mcs->flags) )
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{
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- BUG(); /* XXX multicalls not implemented yet. */
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-
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__set_bit(_MCSF_call_preempted, &mcs->flags);
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for ( i = 0; *p != '\0'; i++ )
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