From 66b83a4cdd3b73effdc285d1d66763c69ffe2ee8 Mon Sep 17 00:00:00 2001 From: Martijn Coenen Date: Mon, 9 Oct 2017 14:26:56 +0200 Subject: binder: call poll_wait() unconditionally. Because we're not guaranteed that subsequent calls to poll() will have a poll_table_struct parameter with _qproc set. When _qproc is not set, poll_wait() is a noop, and we won't be woken up correctly. Signed-off-by: Martijn Coenen Signed-off-by: Greg Kroah-Hartman --- drivers/android/binder.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) (limited to 'drivers/android') diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 0621a95b8597..fddf76ef5bd6 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -3662,12 +3662,6 @@ static void binder_stat_br(struct binder_proc *proc, } } -static int binder_has_thread_work(struct binder_thread *thread) -{ - return !binder_worklist_empty(thread->proc, &thread->todo) || - thread->looper_need_return; -} - static int binder_put_node_cmd(struct binder_proc *proc, struct binder_thread *thread, void __user **ptrp, @@ -4297,12 +4291,9 @@ static unsigned int binder_poll(struct file *filp, binder_inner_proc_unlock(thread->proc); - if (binder_has_work(thread, wait_for_proc_work)) - return POLLIN; - poll_wait(filp, &thread->wait, wait); - if (binder_has_thread_work(thread)) + if (binder_has_work(thread, wait_for_proc_work)) return POLLIN; return 0; -- cgit v1.2.3 From a0c2baaf81bd53dc76fccdddc721ba7dbb62be21 Mon Sep 17 00:00:00 2001 From: Sherry Yang Date: Fri, 20 Oct 2017 20:58:58 -0400 Subject: android: binder: Don't get mm from task MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Use binder_alloc struct's mm_struct rather than getting a reference to the mm struct through get_task_mm to avoid a potential deadlock between lru lock, task lock and dentry lock, since a thread can be holding the task lock and the dentry lock while trying to acquire the lru lock. Acked-by: Arve Hjønnevåg Signed-off-by: Sherry Yang Signed-off-by: Greg Kroah-Hartman --- drivers/android/binder_alloc.c | 22 +++++++++------------- drivers/android/binder_alloc.h | 1 - 2 files changed, 9 insertions(+), 14 deletions(-) (limited to 'drivers/android') diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 064f5e31ec55..e12072b1d507 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -215,17 +215,12 @@ static int binder_update_page_range(struct binder_alloc *alloc, int allocate, } } - if (!vma && need_mm) - mm = get_task_mm(alloc->tsk); + if (!vma && need_mm && mmget_not_zero(alloc->vma_vm_mm)) + mm = alloc->vma_vm_mm; if (mm) { down_write(&mm->mmap_sem); vma = alloc->vma; - if (vma && mm != alloc->vma_vm_mm) { - pr_err("%d: vma mm and task mm mismatch\n", - alloc->pid); - vma = NULL; - } } if (!vma && need_mm) { @@ -720,6 +715,7 @@ int binder_alloc_mmap_handler(struct binder_alloc *alloc, barrier(); alloc->vma = vma; alloc->vma_vm_mm = vma->vm_mm; + mmgrab(alloc->vma_vm_mm); return 0; @@ -795,6 +791,8 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc) vfree(alloc->buffer); } mutex_unlock(&alloc->mutex); + if (alloc->vma_vm_mm) + mmdrop(alloc->vma_vm_mm); binder_alloc_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d buffers %d, pages %d\n", @@ -889,7 +887,6 @@ int binder_alloc_get_allocated_count(struct binder_alloc *alloc) void binder_alloc_vma_close(struct binder_alloc *alloc) { WRITE_ONCE(alloc->vma, NULL); - WRITE_ONCE(alloc->vma_vm_mm, NULL); } /** @@ -926,9 +923,9 @@ enum lru_status binder_alloc_free_page(struct list_head *item, page_addr = (uintptr_t)alloc->buffer + index * PAGE_SIZE; vma = alloc->vma; if (vma) { - mm = get_task_mm(alloc->tsk); - if (!mm) - goto err_get_task_mm_failed; + if (!mmget_not_zero(alloc->vma_vm_mm)) + goto err_mmget; + mm = alloc->vma_vm_mm; if (!down_write_trylock(&mm->mmap_sem)) goto err_down_write_mmap_sem_failed; } @@ -963,7 +960,7 @@ enum lru_status binder_alloc_free_page(struct list_head *item, err_down_write_mmap_sem_failed: mmput_async(mm); -err_get_task_mm_failed: +err_mmget: err_page_already_freed: mutex_unlock(&alloc->mutex); err_get_alloc_mutex_failed: @@ -1002,7 +999,6 @@ struct shrinker binder_shrinker = { */ void binder_alloc_init(struct binder_alloc *alloc) { - alloc->tsk = current->group_leader; alloc->pid = current->group_leader->pid; mutex_init(&alloc->mutex); INIT_LIST_HEAD(&alloc->buffers); diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h index a3a3602c689c..2dd33b6df104 100644 --- a/drivers/android/binder_alloc.h +++ b/drivers/android/binder_alloc.h @@ -100,7 +100,6 @@ struct binder_lru_page { */ struct binder_alloc { struct mutex mutex; - struct task_struct *tsk; struct vm_area_struct *vma; struct mm_struct *vma_vm_mm; void *buffer; -- cgit v1.2.3 From ae65c8510f3319dfb2114cc48d476b81232e27b3 Mon Sep 17 00:00:00 2001 From: Sherry Yang Date: Fri, 20 Oct 2017 20:58:59 -0400 Subject: android: binder: Fix null ptr dereference in debug msg MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Don't access next->data in kernel debug message when the next buffer is null. Acked-by: Arve Hjønnevåg Signed-off-by: Sherry Yang Signed-off-by: Greg Kroah-Hartman --- drivers/android/binder_alloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/android') diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index e12072b1d507..c2819a3d58a6 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -560,7 +560,7 @@ static void binder_delete_free_buffer(struct binder_alloc *alloc, binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, "%d: merge free, buffer %pK do not share page with %pK or %pK\n", alloc->pid, buffer->data, - prev->data, next->data); + prev->data, next ? next->data : NULL); binder_update_page_range(alloc, 0, buffer_start_page(buffer), buffer_start_page(buffer) + PAGE_SIZE, NULL); -- cgit v1.2.3 From b24413180f5600bcb3bb70fbed5cf186b60864bd Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 1 Nov 2017 15:07:57 +0100 Subject: License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- drivers/android/Kconfig | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/android') diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig index 9801d852bd56..7dce3795b887 100644 --- a/drivers/android/Kconfig +++ b/drivers/android/Kconfig @@ -1,3 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 menu "Android" config ANDROID -- cgit v1.2.3