Alexey Kardashevskiy 3e385c0d6c virt: sev-guest: Move SNP Guest Request data pages handling under snp_cmd_mutex ... Compared to the SNP Guest Request, the "Extended" version adds data pages for receiving certificates. If not enough pages provided, the HV can report to the VM how much is needed so the VM can reallocate and repeat. Commit ae596615d9 ("virt: sev-guest: Reduce the scope of SNP command mutex") moved handling of the allocated/desired pages number out of scope of said mutex and create a possibility for a race (multiple instances trying to trigger Extended request in a VM) as there is just one instance of snp_msg_desc per /dev/sev-guest and no locking other than snp_cmd_mutex. Fix the issue by moving the data blob/size and the GHCB input struct (snp_req_data) into snp_guest_req which is allocated on stack now and accessed by the GHCB caller under that mutex. Stop allocating SEV_FW_BLOB_MAX_SIZE in snp_msg_alloc() as only one of four callers needs it. Free the received blob in get_ext_report() right after it is copied to the userspace. Possible future users of snp_send_guest_request() are likely to have different ideas about the buffer size anyways. Fixes: ae596615d9 ("virt: sev-guest: Reduce the scope of SNP command mutex") Signed-off-by: Alexey Kardashevskiy <aik@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikunj A Dadhania <nikunj@amd.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250307013700.437505-3-aik@amd.com		2025-03-07 14:09:33 +01:00
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sev	virt: sev-guest: Move SNP Guest Request data pages handling under snp_cmd_mutex	2025-03-07 14:09:33 +01:00
tdx	x86/tdx: Dump attributes and TD_CTLS on boot	2024-12-05 10:27:07 -08:00
core.c	x86/sev: Add Secure TSC support for SNP guests	2025-01-07 20:27:23 +01:00
Makefile	x86/sev: Move SEV compilation units	2024-07-11 11:55:58 +02:00