linux-stable/drivers/acpi/apei
Takashi Iwai bb82e0b4a7 ACPI: APEI / ERST: Fix missing error handling in erst_reader()
The commit f6f8285132 ("pstore: pass allocated memory region back to
caller") changed the check of the return value from erst_read() in
erst_reader() in the following way:

        if (len == -ENOENT)
                goto skip;
-       else if (len < 0) {
-               rc = -1;
+       else if (len < sizeof(*rcd)) {
+               rc = -EIO;
                goto out;

This introduced another bug: since the comparison with sizeof() is
cast to unsigned, a negative len value doesn't hit any longer.
As a result, when an error is returned from erst_read(), the code
falls through, and it may eventually lead to some weird thing like
memory corruption.

This patch adds the negative error value check more explicitly for
addressing the issue.

Fixes: f6f8285132 (pstore: pass allocated memory region back to caller)
Cc: All applicable <stable@vger.kernel.org>
Tested-by: Jerry Tang <jtang@suse.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-18 12:12:08 +01:00
..
apei-base.c ACPI / APEI: Fix leaked resources 2016-03-11 00:13:25 +01:00
apei-internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
bert.c ACPI: APEI: Fix BERT resources conflict with ACPI NVS area 2017-02-27 22:53:11 +01:00
einj.c ACPI, APEI, EINJ: Subtract any matching Register Region from Trigger resources 2017-08-29 00:32:49 +02:00
erst-dbg.c ACPI: Remove FSF mailing addresses 2015-07-08 02:27:32 +02:00
erst.c ACPI: APEI / ERST: Fix missing error handling in erst_reader() 2017-12-18 12:12:08 +01:00
ghes.c ACPI updates for v4.15-rc1 2017-11-13 20:08:22 -08:00
hest.c ACPI / APEI: Suppress message if HEST not present 2017-08-30 03:11:21 +02:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00