forked from jianmu/TencentOS-kernel
3cbbfad519
commit a5d25e01c8146ad8846da4760422e12242fceafe upstream.
Backport summary: for 5.4 kernel fsgsbase support.
If the kernel erroneously allows WRGSBASE and user code writes a
negative value, paranoid_entry will get confused. Check for this by
writing a negative value to GSBASE and doing SYSENTER with TF set. A
successful run looks like:
[RUN] SYSENTER with TF, invalid state, and GSBASE < 0
[SKIP] Illegal instruction
A failed run causes a kernel hang, and I believe it's because we
double-fault and then get a never ending series of page faults and,
when we exhaust the double fault stack we double fault again,
starting the process over.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/f4f71efc91b9eae5e3dae21c9aee1c70cf5f370e.1590620529.git.luto@kernel.org
(cherry picked from commit a5d25e01c8146ad8846da4760422e12242fceafe)
Signed-off-by: Ethan Zhao <Haifeng.Zhao@intel.com>
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| .. | ||
| fault-injection | ||
| ktest | ||
| nvdimm | ||
| radix-tree | ||
| scatterlist | ||
| selftests | ||
| vsock | ||