/// This semantic patch looks for kmalloc etc that are not followed by a
/// NULL check. It only gives a report in the case where there is some
/// error handling code later in the function, which may be helpful
/// in determining what the error handling code for the call to kmalloc etc
/// should be.
///
// Confidence: High
// Copyright: (C) 2010 Nicolas Palix, DIKU. GPLv2.
// Copyright: (C) 2010 Julia Lawall, DIKU. GPLv2.
// Copyright: (C) 2010 Gilles Muller, INRIA/LiP6. GPLv2.
// URL: http://coccinelle.lip6.fr/
// Comments:
// Options: --no-includes --include-headers
virtual context
virtual org
virtual report
@withtest@
expression x;
position p;
identifier f,fld;
@@
x@p = f(...);
... when != x->fld
\(x == NULL \| x != NULL\)
@fixed depends on context && !org && !report@
expression x,x1;
position p1 != withtest.p;
statement S;
position any withtest.p;
identifier f;
@@
*x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
*x1@p = f(...);
if (!x1) S
// ------------------------------------------------------------------------
@rfixed depends on (org || report) && !context exists@
expression x,x1;
position p1 != withtest.p;
position p2;
statement S;
position any withtest.p;
identifier f;
@@
x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
x1@p = f@p2(...);
if (!x1) S
@script:python depends on org@
p1 << rfixed.p1;
p2 << rfixed.p2;
@@
cocci.print_main("alloc call",p1)
cocci.print_secs("possible model",p2)
@script:python depends on report@
p1 << rfixed.p1;
p2 << rfixed.p2;
@@
msg = "alloc with no test, possible model on line %s" % (p2[0].line)
coccilib.report.print_report(p1[0],msg)
t.cgi/linux/net-next.git/refs/?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>refslogtreecommitdiff
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Some AArch64 UEFI implementations disable the MMU in ExitBootServices(),
after which unaligned accesses to RAM are no longer supported.
Commit:
abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel")
fixed an issue in the memory map handling of the stub FDT code, but
inadvertently created an issue with such firmware, by moving some
of the FDT manipulation to after the invocation of ExitBootServices().
Given that the stub's libfdt implementation uses the ordinary, accelerated
string functions, which rely on hardware handling of unaligned accesses,
manipulating the FDT with the MMU off may result in alignment faults.
So fix the situation by moving the update_fdt_memmap() call into the
callback function invoked by efi_exit_boot_services() right before it
calls the ExitBootServices() UEFI service (which is arguably a better
place for it anyway)
Note that disabling the MMU in ExitBootServices() is not compliant with
the UEFI spec, and carries great risk due to the fact that switching from
cached to uncached memory accesses halfway through compiler generated code
(i.e., involving a stack) can never be done in a way that is architecturally
safe.
Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel")
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Riku Voipio <riku.voipio@linaro.org>
Cc: <stable@vger.kernel.org>
Cc: mark.rutland@arm.com
Cc: linux-efi@vger.kernel.org
Cc: matt@codeblueprint.co.uk
Cc: leif.lindholm@linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>