diff options
author | Philippe Schenker <philippe.schenker@toradex.com> | 2022-05-19 16:29:13 +0200 |
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committer | Philippe Schenker <philippe.schenker@toradex.com> | 2022-05-19 16:29:13 +0200 |
commit | e6fb5c32f78f99682821f91b3959e222c93e4cb9 (patch) | |
tree | 3f6c281a7d83a6e3c0a153f93718f7cd9a39b6f7 /drivers/xen/xenbus/xenbus_probe.c | |
parent | 585dc27c53b6c1a32a7e11b724e91d7297388a13 (diff) | |
parent | b7007e1d615b8d4b71c28ebf790c5164fc4491d5 (diff) |
Merge remote-tracking branch 'gh-fslc/5.4-2.3.x-imx' into toradex_5.4-2.3.x-imx
Diffstat (limited to 'drivers/xen/xenbus/xenbus_probe.c')
-rw-r--r-- | drivers/xen/xenbus/xenbus_probe.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index 652894d61967..b911a91bce6b 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -846,7 +846,7 @@ static struct notifier_block xenbus_resume_nb = { static int __init xenbus_init(void) { - int err = 0; + int err; uint64_t v = 0; xen_store_domain_type = XS_UNKNOWN; @@ -886,6 +886,29 @@ static int __init xenbus_init(void) err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v); if (err) goto out_error; + /* + * Uninitialized hvm_params are zero and return no error. + * Although it is theoretically possible to have + * HVM_PARAM_STORE_PFN set to zero on purpose, in reality it is + * not zero when valid. If zero, it means that Xenstore hasn't + * been properly initialized. Instead of attempting to map a + * wrong guest physical address return error. + * + * Also recognize all bits set as an invalid value. + */ + if (!v || !~v) { + err = -ENOENT; + goto out_error; + } + /* Avoid truncation on 32-bit. */ +#if BITS_PER_LONG == 32 + if (v > ULONG_MAX) { + pr_err("%s: cannot handle HVM_PARAM_STORE_PFN=%llx > ULONG_MAX\n", + __func__, v); + err = -EINVAL; + goto out_error; + } +#endif xen_store_gfn = (unsigned long)v; xen_store_interface = xen_remap(xen_store_gfn << XEN_PAGE_SHIFT, @@ -920,8 +943,10 @@ static int __init xenbus_init(void) */ proc_create_mount_point("xen"); #endif + return 0; out_error: + xen_store_domain_type = XS_UNKNOWN; return err; } |