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 --- lib/audit.c | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 lib/audit.c (limited to 'lib/audit.c') diff --git a/lib/audit.c b/lib/audit.c new file mode 100644 index 000000000..bc07fbd3a --- /dev/null +++ b/lib/audit.c @@ -0,0 +1,89 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include + +static unsigned dir_class[] = { +#include +~0U +}; + +static unsigned read_class[] = { +#include +~0U +}; + +static unsigned write_class[] = { +#include +~0U +}; + +static unsigned chattr_class[] = { +#include +~0U +}; + +static unsigned signal_class[] = { +#include +~0U +}; + +int audit_classify_arch(int arch) +{ + if (audit_is_compat(arch)) + return 1; + else + return 0; +} + +int audit_classify_syscall(int abi, unsigned syscall) +{ + if (audit_is_compat(abi)) + return audit_classify_compat_syscall(abi, syscall); + + switch (syscall) { +#ifdef __NR_open + case __NR_open: + return AUDITSC_OPEN; +#endif +#ifdef __NR_openat + case __NR_openat: + return AUDITSC_OPENAT; +#endif +#ifdef __NR_socketcall + case __NR_socketcall: + return AUDITSC_SOCKETCALL; +#endif +#ifdef __NR_execveat + case __NR_execveat: +#endif + case __NR_execve: + return AUDITSC_EXECVE; +#ifdef __NR_openat2 + case __NR_openat2: + return AUDITSC_OPENAT2; +#endif + default: + return AUDITSC_NATIVE; + } +} + +static int __init audit_classes_init(void) +{ +#ifdef CONFIG_AUDIT_COMPAT_GENERIC + audit_register_class(AUDIT_CLASS_WRITE_32, compat_write_class); + audit_register_class(AUDIT_CLASS_READ_32, compat_read_class); + audit_register_class(AUDIT_CLASS_DIR_WRITE_32, compat_dir_class); + audit_register_class(AUDIT_CLASS_CHATTR_32, compat_chattr_class); + audit_register_class(AUDIT_CLASS_SIGNAL_32, compat_signal_class); +#endif + audit_register_class(AUDIT_CLASS_WRITE, write_class); + audit_register_class(AUDIT_CLASS_READ, read_class); + audit_register_class(AUDIT_CLASS_DIR_WRITE, dir_class); + audit_register_class(AUDIT_CLASS_CHATTR, chattr_class); + audit_register_class(AUDIT_CLASS_SIGNAL, signal_class); + return 0; +} + +__initcall(audit_classes_init); -- cgit v1.3.1