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/security.c | 73 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 fs/jffs2/security.c (limited to 'fs/jffs2/security.c') diff --git a/fs/jffs2/security.c b/fs/jffs2/security.c new file mode 100644 index 000000000..437f3a2c1 --- /dev/null +++ b/fs/jffs2/security.c @@ -0,0 +1,73 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright © 2006 NEC Corporation + * + * Created by KaiGai Kohei + * + * For licensing information, see the file 'LICENCE' in this directory. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "nodelist.h" + +/* ---- Initial Security Label(s) Attachment callback --- */ +static int jffs2_initxattrs(struct inode *inode, + const struct xattr *xattr_array, void *fs_info) +{ + const struct xattr *xattr; + int err = 0; + + for (xattr = xattr_array; xattr->name != NULL; xattr++) { + err = do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY, + xattr->name, xattr->value, + xattr->value_len, 0); + if (err < 0) + break; + } + return err; +} + +/* ---- Initial Security Label(s) Attachment ----------- */ +int jffs2_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr) +{ + return security_inode_init_security(inode, dir, qstr, + &jffs2_initxattrs, NULL); +} + +/* ---- XATTR Handler for "security.*" ----------------- */ +static int jffs2_security_getxattr(const struct xattr_handler *handler, + struct dentry *unused, struct inode *inode, + const char *name, void *buffer, size_t size) +{ + return do_jffs2_getxattr(inode, JFFS2_XPREFIX_SECURITY, + name, buffer, size); +} + +static int jffs2_security_setxattr(const struct xattr_handler *handler, + struct mnt_idmap *idmap, + struct dentry *unused, struct inode *inode, + const char *name, const void *buffer, + size_t size, int flags) +{ + return do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY, + name, buffer, size, flags); +} + +const struct xattr_handler jffs2_security_xattr_handler = { + .prefix = XATTR_SECURITY_PREFIX, + .set = jffs2_security_setxattr, + .get = jffs2_security_getxattr +}; -- cgit v1.3.1