From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- fs/jffs2/writev.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 fs/jffs2/writev.c (limited to 'fs/jffs2/writev.c') diff --git a/fs/jffs2/writev.c b/fs/jffs2/writev.c new file mode 100644 index 000000000..a1bda9dab --- /dev/null +++ b/fs/jffs2/writev.c @@ -0,0 +1,51 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright © 2001-2007 Red Hat, Inc. + * + * Created by David Woodhouse + * + * For licensing information, see the file 'LICENCE' in this directory. + * + */ + +#include +#include +#include "nodelist.h" + +int jffs2_flash_direct_writev(struct jffs2_sb_info *c, const struct kvec *vecs, + unsigned long count, loff_t to, size_t *retlen) +{ + if (!jffs2_is_writebuffered(c)) { + if (jffs2_sum_active()) { + int res; + res = jffs2_sum_add_kvec(c, vecs, count, (uint32_t) to); + if (res) { + return res; + } + } + } + + return mtd_writev(c->mtd, vecs, count, to, retlen); +} + +int jffs2_flash_direct_write(struct jffs2_sb_info *c, loff_t ofs, size_t len, + size_t *retlen, const u_char *buf) +{ + int ret; + ret = mtd_write(c->mtd, ofs, len, retlen, buf); + + if (jffs2_sum_active()) { + struct kvec vecs[1]; + int res; + + vecs[0].iov_base = (unsigned char *) buf; + vecs[0].iov_len = len; + + res = jffs2_sum_add_kvec(c, vecs, 1, (uint32_t) ofs); + if (res) { + return res; + } + } + return ret; +} -- cgit v1.3.1