Shorten local variable names for better readability and flatten loop
indentation levels.
No functionality change.
Signed-off-by: Borislav Petkov <bp@suse.de>
... of microcode patches instead of handing in a pointer which is used
for I/O in an otherwise void function.
Signed-off-by: Borislav Petkov <bp@suse.de>
Don't compute start and end from start and size in order to compute size
again down the path in scan_microcode(). So pass size directly instead
and simplify a bunch. Shorten variable names and remove useless ones.
Signed-off-by: Borislav Petkov <bp@suse.de>
... and only then deref it. Also, shorten some variable names and rename
others so as to diminish the ubiquitous presence of the "mc_" prefix
everywhere and make it a bit more readable.
Use kcalloc so that we don't kfree() uninitialized memory on the unwind
path, as suggested by Quentin.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
We should check the return value of the routines fishing out the proper
microcode and not try to apply if we haven't found a suitable blob.
Signed-off-by: Borislav Petkov <bp@suse.de>
Improper pointer arithmetics when calculating the address of the
extended header could lead to an out of bounds memory read and kernel
panic.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Link: http://lkml.kernel.org/r/20150225094125.GB30434@chrystal.uk.oracle.com
Signed-off-by: Borislav Petkov <bp@suse.de>
We do not check the input data bounds containing the microcode before
copying a struct microcode_intel_header from it. A specially crafted
microcode could cause the kernel to read invalid memory and lead to a
denial-of-service.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1422964824-22056-3-git-send-email-quentin.casasnovas@oracle.com
[ Made error message differ from the next one and flipped comparison. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
mc_saved_tmp is a static array allocated on the stack, we need to make
sure mc_saved_count stays within its bounds, otherwise we're overflowing
the stack in _save_mc(). A specially crafted microcode header could lead
to a kernel crash or potentially kernel execution.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1422964824-22056-1-git-send-email-quentin.casasnovas@oracle.com
Signed-off-by: Borislav Petkov <bp@suse.de>
I'm such a moron! The simple solution of saving the BSP patch
for use on resume was too simple (and wrong!), hint:
sizeof(struct microcode_intel).
What needs to be done instead is to fish out the microcode patch
we have stashed previously and apply that on the BSP in case the
late loader hasn't been utilized.
So do that instead.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141208110820.GB20057@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Normally, we do reapply microcode on resume. However, in the cases where
that microcode comes from the early loader and the late loader hasn't
been utilized yet, there's no easy way for us to go and apply the patch
applied during boot by the early loader.
Thus, reuse the patch stashed by the early loader for the BSP.
Signed-off-by: Borislav Petkov <bp@suse.de>
Fix some typos. One of them was in a struct name, fortunately harmless
because it happened on a "sizeof(struct foo*)" construction.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Link: http://lkml.kernel.org/r/1406146251-8540-1-git-send-email-hmh@hmh.eng.br
Signed-off-by: Borislav Petkov <bp@suse.de>
We've grown a bunch of microcode loader files all prefixed with
"microcode_". They should be under cpu/ because this is strictly
CPU-related functionality so do that and drop the prefix since they're
in their own directory now which gives that prefix. :)
While at it, drop MICROCODE_INTEL_LIB config item and stash the
functionality under CONFIG_MICROCODE_INTEL as it was its only user.
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Borislav Petkov