This is a note to let you know that I've just added the patch titled staging: gasket: Check the return value of gasket_get_bar_index() to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: staging-gasket-check-the-return-value-of-gasket_get_bar_index.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 769acc3656d93aaacada814939743361d284fd87 Mon Sep 17 00:00:00 2001 From: Oscar Carter <oscar.carter@xxxxxxx> Date: Fri, 1 May 2020 17:51:18 +0200 Subject: staging: gasket: Check the return value of gasket_get_bar_index() From: Oscar Carter <oscar.carter@xxxxxxx> commit 769acc3656d93aaacada814939743361d284fd87 upstream. Check the return value of gasket_get_bar_index function as it can return a negative one (-EINVAL). If this happens, a negative index is used in the "gasket_dev->bar_data" array. Addresses-Coverity-ID: 1438542 ("Negative array index read") Fixes: 9a69f5087ccc2 ("drivers/staging: Gasket driver framework + Apex driver") Signed-off-by: Oscar Carter <oscar.carter@xxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Reviewed-by: Richard Yeh <rcy@xxxxxxxxxx> Link: https://lore.kernel.org/r/20200501155118.13380-1-oscar.carter@xxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/gasket/gasket_core.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/staging/gasket/gasket_core.c +++ b/drivers/staging/gasket/gasket_core.c @@ -933,6 +933,10 @@ do_map_region(const struct gasket_dev *g gasket_get_bar_index(gasket_dev, (vma->vm_pgoff << PAGE_SHIFT) + driver_desc->legacy_mmap_address_offset); + + if (bar_index < 0) + return DO_MAP_REGION_INVALID; + phys_base = gasket_dev->bar_data[bar_index].phys_base + phys_offset; while (mapped_bytes < map_length) { /* Patches currently in stable-queue which might be from oscar.carter@xxxxxxx are queue-4.19/staging-gasket-check-the-return-value-of-gasket_get_bar_index.patch