From 33a154a96e71a34a1bcca9f40da343dbbf7b38b4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 1 Oct 2026 14:52:55 +0000 Subject: selftests/bpf: Test packet range of pointers sharing an id Add tests where two packet pointers share an id and tightening one pointer's umax from its var_off would put it less than their constant distance from the other's umax: with an index & 0x38 capped at 50, the base pointer keeps umax 50, so the pointer 8 bytes further on must keep umax 58, even though its known bits allow at most 56. These refused a valid program or accepted an out-of-bounds access before the fix: - check the advanced copy, load through the base: valid, was refused; - check the base, load the byte at base + 1 through a copy advanced by 8: was accepted; - check base + 4, load 4 bytes at base + 2 through base + 8: reads two bytes past the checked range, was accepted; - the same as the second with data_meta pointers checked against data: was accepted. These pass with and without the fix and cover nearby paths: - subtract an unknown scalar from a checked pointer and load below it (the range is kept across a new id); - reach a load through two paths whose checks cover 8 and 7 bytes after the loaded pointer; the second path must not be pruned by the first; - spill a copy of a pointer, check the pointer, fill the copy and load one byte past the checked range: the load is refused, and the copy has the range of the check. Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- drivers/usb/gadget/functions.c | 117 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) create mode 100644 drivers/usb/gadget/functions.c (limited to 'drivers/usb/gadget/functions.c') diff --git a/drivers/usb/gadget/functions.c b/drivers/usb/gadget/functions.c new file mode 100644 index 000000000..70e31c40e --- /dev/null +++ b/drivers/usb/gadget/functions.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include + +#include + +static LIST_HEAD(func_list); +static DEFINE_MUTEX(func_lock); + +static struct usb_function_instance *try_get_usb_function_instance(const char *name) +{ + struct usb_function_driver *fd; + struct usb_function_instance *fi; + + fi = ERR_PTR(-ENOENT); + mutex_lock(&func_lock); + list_for_each_entry(fd, &func_list, list) { + + if (strcmp(name, fd->name)) + continue; + + if (!try_module_get(fd->mod)) { + fi = ERR_PTR(-EBUSY); + break; + } + fi = fd->alloc_inst(); + if (IS_ERR(fi)) + module_put(fd->mod); + else + fi->fd = fd; + break; + } + mutex_unlock(&func_lock); + return fi; +} + +struct usb_function_instance *usb_get_function_instance(const char *name) +{ + struct usb_function_instance *fi; + int ret; + + fi = try_get_usb_function_instance(name); + if (!IS_ERR(fi)) + return fi; + ret = PTR_ERR(fi); + if (ret != -ENOENT) + return fi; + ret = request_module("usbfunc:%s", name); + if (ret < 0) + return ERR_PTR(ret); + return try_get_usb_function_instance(name); +} +EXPORT_SYMBOL_GPL(usb_get_function_instance); + +struct usb_function *usb_get_function(struct usb_function_instance *fi) +{ + struct usb_function *f; + + f = fi->fd->alloc_func(fi); + if (IS_ERR(f)) + return f; + f->fi = fi; + return f; +} +EXPORT_SYMBOL_GPL(usb_get_function); + +void usb_put_function_instance(struct usb_function_instance *fi) +{ + struct module *mod; + + if (!fi || !fi->fd) + return; + + mod = fi->fd->mod; + fi->free_func_inst(fi); + module_put(mod); +} +EXPORT_SYMBOL_GPL(usb_put_function_instance); + +void usb_put_function(struct usb_function *f) +{ + if (!f) + return; + + f->free_func(f); +} +EXPORT_SYMBOL_GPL(usb_put_function); + +int usb_function_register(struct usb_function_driver *newf) +{ + struct usb_function_driver *fd; + int ret; + + ret = -EEXIST; + + mutex_lock(&func_lock); + list_for_each_entry(fd, &func_list, list) { + if (!strcmp(fd->name, newf->name)) + goto out; + } + ret = 0; + list_add_tail(&newf->list, &func_list); +out: + mutex_unlock(&func_lock); + return ret; +} +EXPORT_SYMBOL_GPL(usb_function_register); + +void usb_function_unregister(struct usb_function_driver *fd) +{ + mutex_lock(&func_lock); + list_del(&fd->list); + mutex_unlock(&func_lock); +} +EXPORT_SYMBOL_GPL(usb_function_unregister); -- cgit v1.3.1