diff options
| author | Linus Walleij <linus.walleij@linaro.org> | 2020-05-19 12:59:12 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-06-22 09:05:12 +0200 |
| commit | cceec3c3cbfafea6469373746cff64d436703d6e (patch) | |
| tree | 5bc74a11b07747b86a29a6443d53705384ee7a5c /net | |
| parent | f8a27dee67c08bf7aa56d444271b6b3e20aed9cb (diff) | |
ARM: 8978/1: mm: make act_mm() respect THREAD_SIZE
[ Upstream commit e1de94380af588bdf6ad6f0cc1f75004c35bc096 ]
Recent work with KASan exposed the folling hard-coded bitmask
in arch/arm/mm/proc-macros.S:
bic rd, sp, #8128
bic rd, rd, #63
This forms the bitmask 0x1FFF that is coinciding with
(PAGE_SIZE << THREAD_SIZE_ORDER) - 1, this code was assuming
that THREAD_SIZE is always 8K (8192).
As KASan was increasing THREAD_SIZE_ORDER to 2, I ran into
this bug.
Fix it by this little oneline suggested by Ard:
bic rd, sp, #(THREAD_SIZE - 1) & ~63
Where THREAD_SIZE is defined using THREAD_SIZE_ORDER.
We have to also include <linux/const.h> since the THREAD_SIZE
expands to use the _AC() macro.
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
0 files changed, 0 insertions, 0 deletions