linux/drivers/android/binder_alloc.c, branch v6.3

mm: remove zap_page_range and create zap_vma_pages

2023-01-19T01:12:55Z

zap_page_range was originally designed to unmap pages within an address range that could span multiple vmas. While working on [1], it was discovered that all callers of zap_page_range pass a range entirely within a single vma. In addition, the mmu notification call within zap_page range does not correctly handle ranges that span multiple vmas. When crossing a vma boundary, a new mmu_notifier_range_init/end call pair with the new vma should be made. Instead of fixing zap_page_range, do the following: - Create a new routine zap_vma_pages() that will remove all pages within the passed vma. Most users of zap_page_range pass the entire vma and can use this new routine. - For callers of zap_page_range not passing the entire vma, instead call zap_page_range_single(). - Remove zap_page_range. [1] https://lore.kernel.org/linux-mm/20221114235507.294320-2-mike.kravetz@oracle.com/ Link: https://lkml.kernel.org/r/20230104002732.232573-1-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz Suggested-by: Peter Xu Acked-by: Michal Hocko Acked-by: Peter Xu Acked-by: Heiko Carstens [s390] Reviewed-by: Christoph Hellwig Cc: Christian Borntraeger Cc: Christian Brauner Cc: Dave Hansen Cc: David Hildenbrand Cc: Eric Dumazet Cc: Matthew Wilcox Cc: Michael Ellerman Cc: Nadav Amit Cc: Palmer Dabbelt Cc: Rik van Riel Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton

binder: validate alloc->mm in ->mmap() handler

2022-11-09T14:41:27Z

Since commit 1da52815d5f1 ("binder: fix alloc->vma_vm_mm null-ptr dereference") binder caches a pointer to the current->mm during open(). This fixes a null-ptr dereference reported by syzkaller. Unfortunately, it also opens the door for a process to update its mm after the open(), (e.g. via execve) making the cached alloc->mm pointer invalid. Things get worse when the process continues to mmap() a vma. From this point forward, binder will attempt to find this vma using an obsolete alloc->mm reference. Such as in binder_update_page_range(), where the wrong vma is obtained via vma_lookup(), yet binder proceeds to happily insert new pages into it. To avoid this issue fail the ->mmap() callback if we detect a mismatch between the vma->vm_mm and the original alloc->mm pointer. This prevents alloc->vm_addr from getting set, so that any subsequent vma_lookup() calls fail as expected. Fixes: 1da52815d5f1 ("binder: fix alloc->vma_vm_mm null-ptr dereference") Reported-by: Jann Horn Cc: # 5.15+ Signed-off-by: Carlos Llamas Acked-by: Todd Kjos Link: https://lore.kernel.org/r/20221104231235.348958-1-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

binder: remove binder_alloc_set_vma()

2022-09-06T15:02:06Z

The mmap_locked asserts here are not needed since this is only called back from the mmap stack in ->mmap() and ->close() which always acquire the lock first. Remove these asserts along with binder_alloc_set_vma() altogether since it's trivial enough to be consumed by callers. Cc: Liam R. Howlett Signed-off-by: Carlos Llamas Link: https://lore.kernel.org/r/20220906135948.3048225-3-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

binder: rename alloc->vma_vm_mm to alloc->mm

2022-09-06T15:02:06Z

Rename ->vma_vm_mm to ->mm to reflect the fact that we no longer cache this reference from vma->vm_mm but from current->mm instead. No functional changes in this patch. Reviewed-by: Christian Brauner (Microsoft) Acked-by: Todd Kjos Signed-off-by: Carlos Llamas Link: https://lore.kernel.org/r/20220906135948.3048225-2-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

Merge tag 'char-misc-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2022-09-02T17:50:08Z

Pull char/misc driver fixes from Greg KH: "Here are some small char/misc and other driver fixes for 6.0-rc4. Included in here are: - binder fixes for previous fixes, and a few more fixes uncovered by them. - iio driver fixes - soundwire driver fixes - fastrpc driver fixes for memory corruption on some hardware - peci driver fix - mhi driver fix All of these have been in linux-next with no reported problems" * tag 'char-misc-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: binder: fix alloc->vma_vm_mm null-ptr dereference misc: fastrpc: increase maximum session count misc: fastrpc: fix memory corruption on open misc: fastrpc: fix memory corruption on probe soundwire: qcom: fix device status array range bus: mhi: host: Fix up null pointer access in mhi_irq_handler soundwire: qcom: remove duplicate reset control get iio: light: cm32181: make cm32181_pm_ops static iio: ad7292: Prevent regulator double disable dt-bindings: iio: gyroscope: bosch,bmg160: correct number of pins iio: adc: mcp3911: use correct formula for AD conversion iio: adc: mcp3911: correct "microchip,device-addr" property Revert "binder_alloc: Add missing mmap_lock calls when using the VMA" binder_alloc: Add missing mmap_lock calls when using the VMA binder: fix UAF of ref->proc caused by race condition iio: light: cm3605: Fix an error handling path in cm3605_probe() iio: adc: mcp3911: make use of the sign bit peci: cpu: Fix use-after-free in adev_release() peci: aspeed: fix error check return value of platform_get_irq()

binder: fix alloc->vma_vm_mm null-ptr dereference

2022-09-01T14:16:05Z

Syzbot reported a couple issues introduced by commit 44e602b4e52f ("binder_alloc: add missing mmap_lock calls when using the VMA"), in which we attempt to acquire the mmap_lock when alloc->vma_vm_mm has not been initialized yet. This can happen if a binder_proc receives a transaction without having previously called mmap() to setup the binder_proc->alloc space in [1]. Also, a similar issue occurs via binder_alloc_print_pages() when we try to dump the debugfs binder stats file in [2]. Sample of syzbot's crash report: ================================================================== KASAN: null-ptr-deref in range [0x0000000000000128-0x000000000000012f] CPU: 0 PID: 3755 Comm: syz-executor229 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0 syz-executor229[3755] cmdline: ./syz-executor2294415195 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 RIP: 0010:__lock_acquire+0xd83/0x56d0 kernel/locking/lockdep.c:4923 [...] Call Trace: lock_acquire kernel/locking/lockdep.c:5666 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631 down_read+0x98/0x450 kernel/locking/rwsem.c:1499 mmap_read_lock include/linux/mmap_lock.h:117 [inline] binder_alloc_new_buf_locked drivers/android/binder_alloc.c:405 [inline] binder_alloc_new_buf+0xa5/0x19e0 drivers/android/binder_alloc.c:593 binder_transaction+0x242e/0x9a80 drivers/android/binder.c:3199 binder_thread_write+0x664/0x3220 drivers/android/binder.c:3986 binder_ioctl_write_read drivers/android/binder.c:5036 [inline] binder_ioctl+0x3470/0x6d00 drivers/android/binder.c:5323 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] ================================================================== Fix these issues by setting up alloc->vma_vm_mm pointer during open() and caching directly from current->mm. This guarantees we have a valid reference to take the mmap_lock during scenarios described above. [1] https://syzkaller.appspot.com/bug?extid=f7dc54e5be28950ac459 [2] https://syzkaller.appspot.com/bug?extid=a75ebe0452711c9e56d9 Fixes: 44e602b4e52f ("binder_alloc: add missing mmap_lock calls when using the VMA") Cc: # v5.15+ Cc: Liam R. Howlett Reported-by: syzbot+f7dc54e5be28950ac459@syzkaller.appspotmail.com Reported-by: syzbot+a75ebe0452711c9e56d9@syzkaller.appspotmail.com Reviewed-by: Liam R. Howlett Acked-by: Todd Kjos Signed-off-by: Carlos Llamas Link: https://lore.kernel.org/r/20220829201254.1814484-2-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman

binder_alloc: add missing mmap_lock calls when using the VMA

2022-08-28T21:02:44Z

Take the mmap_read_lock() when using the VMA in binder_alloc_print_pages() and when checking for a VMA in binder_alloc_new_buf_locked(). It is worth noting binder_alloc_new_buf_locked() drops the VMA read lock after it verifies a VMA exists, but may be taken again deeper in the call stack, if necessary. Link: https://lkml.kernel.org/r/20220810160209.1630707-1-Liam.Howlett@oracle.com Fixes: a43cfc87caaf (android: binder: stop saving a pointer to the VMA) Signed-off-by: Liam R. Howlett Reported-by: Ondrej Mosnacek Reported-by: Acked-by: Carlos Llamas Tested-by: Ondrej Mosnacek Cc: Minchan Kim Cc: Christian Brauner (Microsoft) Cc: Greg Kroah-Hartman Cc: Hridya Valsaraju Cc: Joel Fernandes Cc: Martijn Coenen Cc: Suren Baghdasaryan Cc: Todd Kjos Cc: Matthew Wilcox (Oracle) Cc: "Arve Hjønnevåg" Signed-off-by: Andrew Morton

Revert "binder_alloc: Add missing mmap_lock calls when using the VMA"

2022-08-19T08:55:54Z

This reverts commit d6f35446d0769a98e9d761593d267cdd24f09ecd. It is coming in through Andrew's tree instead, and for some reason we have different versions. I trust the version from Andrew more as the original offending commit came through his tree. Fixes: d6f35446d076 ("binder_alloc: Add missing mmap_lock calls when using the VMA") Cc: stable Cc: Ondrej Mosnacek Cc: Ondrej Mosnacek Cc: Carlos Llamas Cc: Liam R. Howlett Reported-by: Stephen Rothwell Link: https://lore.kernel.org/r/20220819184027.7b3fda3e@canb.auug.org.au Signed-off-by: Greg Kroah-Hartman

binder_alloc: Add missing mmap_lock calls when using the VMA

2022-08-18T14:31:02Z

Take the mmap_read_lock() when using the VMA in binder_alloc_print_pages() and when checking for a VMA in binder_alloc_new_buf_locked(). It is worth noting binder_alloc_new_buf_locked() drops the VMA read lock after it verifies a VMA exists, but may be taken again deeper in the call stack, if necessary. Fixes: a43cfc87caaf (android: binder: stop saving a pointer to the VMA) Cc: stable Reported-by: Ondrej Mosnacek Reported-by: syzbot+a7b60a176ec13cafb793@syzkaller.appspotmail.com Tested-by: Ondrej Mosnacek Acked-by: Carlos Llamas Signed-off-by: Liam R. Howlett Link: https://lore.kernel.org/r/20220810160209.1630707-1-Liam.Howlett@oracle.com Signed-off-by: Greg Kroah-Hartman

android: binder: fix lockdep check on clearing vma

2022-07-30T01:07:13Z

When munmapping a vma, the mmap_lock can be degraded to a write before calling close() on the file handle. The binder close() function calls binder_alloc_set_vma() to clear the vma address, which now has a lock dep check for writing on the mmap_lock. Change the lockdep check to ensure the reading lock is held while clearing and keep the write check while writing. Link: https://lkml.kernel.org/r/20220627151857.2316964-1-Liam.Howlett@oracle.com Fixes: 472a68df605b ("android: binder: stop saving a pointer to the VMA") Signed-off-by: Liam R. Howlett Reported-by: syzbot+da54fa8d793ca89c741f@syzkaller.appspotmail.com Acked-by: Todd Kjos Cc: "Arve Hjønnevåg" Cc: Christian Brauner (Microsoft) Cc: Greg Kroah-Hartman Cc: Hridya Valsaraju Cc: Joel Fernandes Cc: Martijn Coenen Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton