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| author | Lukasz Bartosik <lb@semihalf.com> | 2021-04-02 00:51:49 +0200 |
|---|---|---|
| committer | Stephen Boyd <sboyd@kernel.org> | 2021-04-02 23:56:14 -0700 |
| commit | 7045465500e465b09f09d6e5bdc260a9f1aab97b (patch) | |
| tree | 968ff4639e56b0d9085d3e4f7c8d56d7e3e84563 /drivers/clk/clk-fixed-factor.c | |
| parent | 8d3c0c01cb2e36b2bf3c06a82b18b228d0c8f5d0 (diff) | |
| download | linux-7045465500e465b09f09d6e5bdc260a9f1aab97b.tar.bz2 | |
clk: fix invalid usage of list cursor in unregister
Fix invalid usage of a list_for_each_entry cursor in
clk_notifier_unregister(). When list is empty or if the list
is completely traversed (without breaking from the loop on one
of the entries) then the list cursor does not point to a valid
entry and therefore should not be used. The patch fixes a logical
bug that hasn't been seen in pratice however it is analogus
to the bug fixed in clk_notifier_register().
The issue was dicovered when running 5.12-rc1 kernel on x86_64
with KASAN enabled:
BUG: KASAN: global-out-of-bounds in clk_notifier_register+0xab/0x230
Read of size 8 at addr ffffffffa0d10588 by task swapper/0/1
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc1 #1
Hardware name: Google Caroline/Caroline,
BIOS Google_Caroline.7820.430.0 07/20/2018
Call Trace:
dump_stack+0xee/0x15c
print_address_description+0x1e/0x2dc
kasan_report+0x188/0x1ce
? clk_notifier_register+0xab/0x230
? clk_prepare_lock+0x15/0x7b
? clk_notifier_register+0xab/0x230
clk_notifier_register+0xab/0x230
dw8250_probe+0xc01/0x10d4
...
Memory state around the buggy address:
ffffffffa0d10480: 00 00 00 00 00 03 f9 f9 f9 f9 f9 f9 00 00 00 00
ffffffffa0d10500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9
>ffffffffa0d10580: f9 f9 f9 f9 00 00 00 00 00 00 00 00 00 00 00 00
^
ffffffffa0d10600: 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 00 00 00 00
ffffffffa0d10680: 00 00 00 00 00 00 00 00 f9 f9 f9 f9 00 00 00 00
==================================================================
Fixes: b2476490ef11 ("clk: introduce the common clock framework")
Reported-by: Lukasz Majczak <lma@semihalf.com>
Signed-off-by: Lukasz Bartosik <lb@semihalf.com>
Link: https://lore.kernel.org/r/20210401225149.18826-2-lb@semihalf.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Diffstat (limited to 'drivers/clk/clk-fixed-factor.c')
0 files changed, 0 insertions, 0 deletions