Commit 779c5927 authored by Alexander Usyskin's avatar Alexander Usyskin Committed by Miquel Raynal
Browse files

mtd: intel-dg: Fix accessing regions before setting nregions 



The regions array is counted by nregions, but it's set only after
accessing it:

[] UBSAN: array-index-out-of-bounds in drivers/mtd/devices/mtd_intel_dg.c:750:15
[] index 0 is out of range for type '<unknown> [*]'

Fix it by also fixing an undesired behavior: the loop silently ignores
ENOMEM and continues setting the other entries.

CC: Gustavo A. R. Silva <gustavoars@kernel.org>
CC: Raag Jadav <raag.jadav@intel.com>
Reported-by: default avatarJani Partanen <jiipee@sotapeli.fi>
Closes: https://lore.kernel.org/all/caca6c67-4f1d-49f1-948f-e63b6b937b29@sotapeli.fi


Fixes: ceb5ab3c ("mtd: add driver for intel graphics non-volatile memory device")
Signed-off-by: default avatarLucas De Marchi <demarchi@kernel.org>
Signed-off-by: default avatarAlexander Usyskin <alexander.usyskin@intel.com>
Reviewed-by: default avatarRaag Jadav <raag.jadav@intel.com>
Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
parent 90541270

drivers/mtd/devices/mtd_intel_dg.c

+6 −3
Original line number Diff line number Diff line
@@ -770,6 +770,7 @@ static int intel_dg_mtd_probe(struct auxiliary_device *aux_dev, 


	kref_init(&nvm->refcnt);

	mutex_init(&nvm->lock);

	nvm->nregions = nregions;



	for (n = 0, i = 0; i < INTEL_DG_NVM_REGIONS; i++) {

		if (!invm->regions[i].name)
@@ -777,13 +778,15 @@ static int intel_dg_mtd_probe(struct auxiliary_device *aux_dev, 


		char *name = kasprintf(GFP_KERNEL, "%s.%s",

				       dev_name(&aux_dev->dev), invm->regions[i].name);

		if (!name)

			continue;

		if (!name) {

			ret = -ENOMEM;

			goto err;

		}



		nvm->regions[n].name = name;

		nvm->regions[n].id = i;

		n++;

	}

	nvm->nregions = n; /* in case where kasprintf fail */



	ret = devm_pm_runtime_enable(device);

	if (ret < 0) {