linux/drivers/android/binder.c, branch v6.8

binder: signal epoll threads of self-work

2024-01-31T22:08:28Z

In (e)poll mode, threads often depend on I/O events to determine when data is ready for consumption. Within binder, a thread may initiate a command via BINDER_WRITE_READ without a read buffer and then make use of epoll_wait() or similar to consume any responses afterwards. It is then crucial that epoll threads are signaled via wakeup when they queue their own work. Otherwise, they risk waiting indefinitely for an event leaving their work unhandled. What is worse, subsequent commands won't trigger a wakeup either as the thread has pending work. Fixes: 457b9a6f09f0 ("Staging: android: add binder driver") Cc: Arve Hjønnevåg Cc: Martijn Coenen Cc: Alice Ryhl Cc: Steven Moreland Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Carlos Llamas Link: https://lore.kernel.org/r/20240131215347.1808751-1-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

Merge tag 'char-misc-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2024-01-18T00:47:17Z

Pull char/misc and other driver updates from Greg KH: "Here is the big set of char/misc and other driver subsystem changes for 6.8-rc1. Other than lots of binder driver changes (as you can see by the merge conflicts) included in here are: - lots of iio driver updates and additions - spmi driver updates - eeprom driver updates - firmware driver updates - ocxl driver updates - mhi driver updates - w1 driver updates - nvmem driver updates - coresight driver updates - platform driver remove callback api changes - tags.sh script updates - bus_type constant marking cleanups - lots of other small driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (341 commits) android: removed duplicate linux/errno uio: Fix use-after-free in uio_open drivers: soc: xilinx: add check for platform firmware: xilinx: Export function to use in other module scripts/tags.sh: remove find_sources scripts/tags.sh: use -n to test archinclude scripts/tags.sh: add local annotation scripts/tags.sh: use more portable -path instead of -wholename scripts/tags.sh: Update comment (addition of gtags) firmware: zynqmp: Convert to platform remove callback returning void firmware: turris-mox-rwtm: Convert to platform remove callback returning void firmware: stratix10-svc: Convert to platform remove callback returning void firmware: stratix10-rsu: Convert to platform remove callback returning void firmware: raspberrypi: Convert to platform remove callback returning void firmware: qemu_fw_cfg: Convert to platform remove callback returning void firmware: mtk-adsp-ipc: Convert to platform remove callback returning void firmware: imx-dsp: Convert to platform remove callback returning void firmware: coreboot_table: Convert to platform remove callback returning void firmware: arm_scpi: Convert to platform remove callback returning void firmware: arm_scmi: Convert to platform remove callback returning void ...

file: s/close_fd_get_file()/file_close_fd()/g

2023-12-12T13:24:13Z

That really shouldn't have "get" in there as that implies we're bumping the reference count which we don't do at all. We used to but not anmore. Now we're just closing the fd and pick that file from the fdtable without bumping the reference count. Update the wrong documentation while at it. Link: https://lore.kernel.org/r/20231130-vfs-files-fixes-v1-1-e73ca6f4ea83@kernel.org Reviewed-by: Jan Kara Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner

binder: avoid user addresses in debug logs

2023-12-05T00:23:40Z

Prefer logging vma offsets instead of addresses or simply drop the debug log altogether if not useful. Note this covers the instances affected by the switch to store addresses as unsigned long. However, there are other sections in the driver that could do the same. Signed-off-by: Carlos Llamas Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20231201172212.1813387-27-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

binder: remove pid param in binder_alloc_new_buf()

2023-12-05T00:23:39Z

Binder attributes the buffer allocation to the current->tgid everytime. There is no need to pass this as a parameter so drop it. Also add a few touchups to follow the coding guidelines. No functional changes are introduced in this patch. Reviewed-by: Alice Ryhl Signed-off-by: Carlos Llamas Link: https://lore.kernel.org/r/20231201172212.1813387-13-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

binder: keep vma addresses type as unsigned long

2023-12-05T00:23:38Z

The vma addresses in binder are currently stored as void __user *. This requires casting back and forth between the mm/ api which uses unsigned long. Since we also do internal arithmetic on these addresses we end up having to cast them _again_ to an integer type. Lets stop all the unnecessary casting which kills code readability and store the virtual addresses as the native unsigned long from mm/. Note that this approach is preferred over uintptr_t as Linus explains in [1]. Opportunistically add a few cosmetic touchups. Link: https://lore.kernel.org/all/CAHk-=wj2OHy-5e+srG1fy+ZU00TmZ1NFp6kFLbVLMXHe7A1d-g@mail.gmail.com/ [1] Signed-off-by: Carlos Llamas Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20231201172212.1813387-10-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

binder: use EPOLLERR from eventpoll.h

2023-12-05T00:23:37Z

Use EPOLLERR instead of POLLERR to make sure it is cast to the correct __poll_t type. This fixes the following sparse issue: drivers/android/binder.c:5030:24: warning: incorrect type in return expression (different base types) drivers/android/binder.c:5030:24: expected restricted __poll_t drivers/android/binder.c:5030:24: got int Fixes: f88982679f54 ("binder: check for binder_thread allocation failure in binder_poll()") Cc: stable@vger.kernel.org Cc: Eric Biggers Reviewed-by: Alice Ryhl Signed-off-by: Carlos Llamas Link: https://lore.kernel.org/r/20231201172212.1813387-2-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

binder: fix memory leaks of spam and pending work

2023-10-05T10:48:08Z

A transaction complete work is allocated and queued for each transaction. Under certain conditions the work->type might be marked as BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT to notify userspace about potential spamming threads or as BINDER_WORK_TRANSACTION_PENDING when the target is currently frozen. However, these work types are not being handled in binder_release_work() so they will leak during a cleanup. This was reported by syzkaller with the following kmemleak dump: BUG: memory leak unreferenced object 0xffff88810e2d6de0 (size 32): comm "syz-executor338", pid 5046, jiffies 4294968230 (age 13.590s) hex dump (first 32 bytes): e0 6d 2d 0e 81 88 ff ff e0 6d 2d 0e 81 88 ff ff .m-......m-..... 04 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmalloc_trace+0x25/0x90 mm/slab_common.c:1114 [] kmalloc include/linux/slab.h:599 [inline] [] kzalloc include/linux/slab.h:720 [inline] [] binder_transaction+0x573/0x4050 drivers/android/binder.c:3152 [] binder_thread_write+0x6b5/0x1860 drivers/android/binder.c:4010 [] binder_ioctl_write_read drivers/android/binder.c:5066 [inline] [] binder_ioctl+0x1b2c/0x3cf0 drivers/android/binder.c:5352 [] vfs_ioctl fs/ioctl.c:51 [inline] [] __do_sys_ioctl fs/ioctl.c:871 [inline] [] __se_sys_ioctl fs/ioctl.c:857 [inline] [] __x64_sys_ioctl+0xf2/0x140 fs/ioctl.c:857 [] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 [] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fix the leaks by kfreeing these work types in binder_release_work() and handle them as a BINDER_WORK_TRANSACTION_COMPLETE cleanup. Cc: stable@vger.kernel.org Fixes: 0567461a7a6e ("binder: return pending info for frozen async txns") Fixes: a7dc1e6f99df ("binder: tell userspace to dump current backtrace when detected oneway spamming") Reported-by: syzbot+7f10c1653e35933c0f1e@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7f10c1653e35933c0f1e Suggested-by: Alice Ryhl Signed-off-by: Carlos Llamas Reviewed-by: Alice Ryhl Acked-by: Todd Kjos Link: https://lore.kernel.org/r/20230922175138.230331-1-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

Merge 6.5-rc6 into char-misc-next

2023-08-13T20:14:51Z

We need the char/misc fixes in here as well to build on top of. Signed-off-by: Greg Kroah-Hartman

android: Remove error checking for debugfs_create_dir()

2023-08-04T13:28:01Z

It is expected that most callers should _ignore_ the errors return by debugfs_create_dir() in binder_init(). Signed-off-by: Wang Ming Link: https://lore.kernel.org/r/20230713080649.1893-1-machel@vivo.com Signed-off-by: Greg Kroah-Hartman