This is a note to let you know that I've just added the patch titled
firmware: xilinx: fix out-of-bounds access
to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From f3217d6f2f7a76b36a3326ad58c8897f4d5fbe31 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann arnd@arndb.de Date: Mon, 26 Oct 2020 16:54:36 +0100 Subject: firmware: xilinx: fix out-of-bounds access
The zynqmp_pm_set_suspend_mode() and zynqmp_pm_get_trustzone_version() functions pass values as api_id into zynqmp_pm_invoke_fn that are beyond PM_API_MAX, resulting in an out-of-bounds access:
drivers/firmware/xilinx/zynqmp.c: In function 'zynqmp_pm_set_suspend_mode': drivers/firmware/xilinx/zynqmp.c:150:24: warning: array subscript 2562 is above array bounds of 'u32[64]' {aka 'unsigned int[64]'} [-Warray-bounds] 150 | if (zynqmp_pm_features[api_id] != PM_FEATURE_UNCHECKED) | ~~~~~~~~~~~~~~~~~~^~~~~~~~ drivers/firmware/xilinx/zynqmp.c:28:12: note: while referencing 'zynqmp_pm_features' 28 | static u32 zynqmp_pm_features[PM_API_MAX]; | ^~~~~~~~~~~~~~~~~~
Replace the resulting undefined behavior with an error return. This may break some things that happen to work at the moment but seems better than randomly overwriting kernel data.
I assume we need additional fixes for the two functions that now return an error.
Fixes: 76582671eb5d ("firmware: xilinx: Add Zynqmp firmware driver") Fixes: e178df31cf41 ("firmware: xilinx: Implement ZynqMP power management APIs") Signed-off-by: Arnd Bergmann arnd@arndb.de Link: https://lore.kernel.org/r/20201026155449.3703142-1-arnd@kernel.org Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/firmware/xilinx/zynqmp.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c index 8d1ff2454e2e..efb8a66efc68 100644 --- a/drivers/firmware/xilinx/zynqmp.c +++ b/drivers/firmware/xilinx/zynqmp.c @@ -147,6 +147,9 @@ static int zynqmp_pm_feature(u32 api_id) return 0;
/* Return value if feature is already checked */ + if (api_id > ARRAY_SIZE(zynqmp_pm_features)) + return PM_FEATURE_INVALID; + if (zynqmp_pm_features[api_id] != PM_FEATURE_UNCHECKED) return zynqmp_pm_features[api_id];