From: Tom Lendacky thomas.lendacky@amd.com
stable inclusion from stable-v5.10.137 commit 87af9b0b45666ca3dd6b10c0ece691c740b0f750 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 1b05ece0c931536c0a38a9385e243a7962e933f6 ]
On shutdown, each CCP device instance performs shutdown processing. However, __sev_platform_shutdown_locked() uses the controlling psp structure to obtain the pointer to the sev_device structure. However, during driver initialization, it is possible that an error can be received from the firmware that results in the sev_data pointer being cleared from the controlling psp structure. The __sev_platform_shutdown_locked() function does not check for this situation and will segfault.
While not common, this scenario should be accounted for. Add a check for a NULL sev_device structure before attempting to use it.
Fixes: 5441a07a127f ("crypto: ccp - shutdown SEV firmware on kexec") Signed-off-by: Tom Lendacky thomas.lendacky@amd.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Wei Li liwei391@huawei.com --- drivers/crypto/ccp/sev-dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 57b57d4db500..ed39a22e1b2b 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -278,7 +278,7 @@ static int __sev_platform_shutdown_locked(int *error) struct sev_device *sev = psp_master->sev_data; int ret;
- if (sev->state == SEV_STATE_UNINIT) + if (!sev || sev->state == SEV_STATE_UNINIT) return 0;
ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);