lkml.org 
[lkml]   [2022]   [Sep]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.19 093/155] clk: bcm: rpi: Prevent out-of-bounds access
    Date
    From: Stefan Wahren <stefan.wahren@i2se.com>

    [ Upstream commit bc163555603e4ae9c817675ad80d618a4cdbfa2d ]

    The while loop in raspberrypi_discover_clocks() relies on the assumption
    that the id of the last clock element is zero. Because this data comes
    from the Videocore firmware and it doesn't guarantuee such a behavior
    this could lead to out-of-bounds access. So fix this by providing
    a sentinel element.

    Fixes: 93d2725affd6 ("clk: bcm: rpi: Discover the firmware clocks")
    Link: https://github.com/raspberrypi/firmware/issues/1688
    Suggested-by: Phil Elwell <phil@raspberrypi.com>
    Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
    Link: https://lore.kernel.org/r/20220713154953.3336-2-stefan.wahren@i2se.com
    Acked-by: Florian Fainelli <f.fainelli@gmail.com>
    Reviewed-by: Ivan T. Ivanov <iivanov@suse.de>
    Signed-off-by: Stephen Boyd <sboyd@kernel.org>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    drivers/clk/bcm/clk-raspberrypi.c | 7 ++++++-
    1 file changed, 6 insertions(+), 1 deletion(-)

    diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
    index 39d63c983d62c..e495f5f382ab9 100644
    --- a/drivers/clk/bcm/clk-raspberrypi.c
    +++ b/drivers/clk/bcm/clk-raspberrypi.c
    @@ -344,8 +344,13 @@ static int raspberrypi_discover_clocks(struct raspberrypi_clk *rpi,
    struct rpi_firmware_get_clocks_response *clks;
    int ret;

    + /*
    + * The firmware doesn't guarantee that the last element of
    + * RPI_FIRMWARE_GET_CLOCKS is zeroed. So allocate an additional
    + * zero element as sentinel.
    + */
    clks = devm_kcalloc(rpi->dev,
    - RPI_FIRMWARE_NUM_CLK_ID, sizeof(*clks),
    + RPI_FIRMWARE_NUM_CLK_ID + 1, sizeof(*clks),
    GFP_KERNEL);
    if (!clks)
    return -ENOMEM;
    --
    2.35.1


    \
     
     \ /
      Last update: 2022-09-06 16:11    [W:4.516 / U:0.656 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site