From: James Kim Date: Mon, 9 Mar 2026 06:05:12 +0000 (+0900) Subject: mtd: docg3: fix use-after-free in docg3_release() X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=ca19808bc6fac7e29420d8508df569b346b3e339;p=thirdparty%2Fkernel%2Flinux.git mtd: docg3: fix use-after-free in docg3_release() In docg3_release(), the docg3 pointer is obtained from cascade->floors[0]->priv before the loop that calls doc_release_device() on each floor. doc_release_device() frees the docg3 struct via kfree(docg3) at line 1881. After the loop, docg3->cascade->bch dereferences the already-freed pointer. Fix this by accessing cascade->bch directly, which is equivalent since docg3->cascade points back to the same cascade struct, and is already available as a local variable. This also removes the now-unused docg3 local variable. Fixes: c8ae3f744ddc ("lib/bch: Rework a little bit the exported function names") Cc: stable@vger.kernel.org Signed-off-by: James Kim Signed-off-by: Miquel Raynal --- diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c index 33050a2a80f79..603fd0efc2ea2 100644 --- a/drivers/mtd/devices/docg3.c +++ b/drivers/mtd/devices/docg3.c @@ -2049,7 +2049,6 @@ err_probe: static void docg3_release(struct platform_device *pdev) { struct docg3_cascade *cascade = platform_get_drvdata(pdev); - struct docg3 *docg3 = cascade->floors[0]->priv; int floor; doc_unregister_sysfs(pdev, cascade); @@ -2057,7 +2056,7 @@ static void docg3_release(struct platform_device *pdev) if (cascade->floors[floor]) doc_release_device(cascade->floors[floor]); - bch_free(docg3->cascade->bch); + bch_free(cascade->bch); } #ifdef CONFIG_OF