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author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-15 10:01:51 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-15 10:01:51 -0700 |
commit | 726eb70e0d34dc4bc4dada71f52bba8ed638431e (patch) | |
tree | e49674616f4513c8c6a4746a08e93c9441708d34 /drivers/android/binder_alloc.c | |
parent | c6dbef7307629cce855aa6b482b60cbf7777ed88 (diff) | |
parent | f3277cbfba763cd2826396521b9296de67cf1bbc (diff) | |
download | linux-726eb70e0d34dc4bc4dada71f52bba8ed638431e.tar.bz2 |
Merge tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the big set of char, misc, and other assorted driver subsystem
patches for 5.10-rc1.
There's a lot of different things in here, all over the drivers/
directory. Some summaries:
- soundwire driver updates
- habanalabs driver updates
- extcon driver updates
- nitro_enclaves new driver
- fsl-mc driver and core updates
- mhi core and bus updates
- nvmem driver updates
- eeprom driver updates
- binder driver updates and fixes
- vbox minor bugfixes
- fsi driver updates
- w1 driver updates
- coresight driver updates
- interconnect driver updates
- misc driver updates
- other minor driver updates
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (396 commits)
binder: fix UAF when releasing todo list
docs: w1: w1_therm: Fix broken xref, mistakes, clarify text
misc: Kconfig: fix a HISI_HIKEY_USB dependency
LSM: Fix type of id parameter in kernel_post_load_data prototype
misc: Kconfig: add a new dependency for HISI_HIKEY_USB
firmware_loader: fix a kernel-doc markup
w1: w1_therm: make w1_poll_completion static
binder: simplify the return expression of binder_mmap
test_firmware: Test partial read support
firmware: Add request_partial_firmware_into_buf()
firmware: Store opt_flags in fw_priv
fs/kernel_file_read: Add "offset" arg for partial reads
IMA: Add support for file reads without contents
LSM: Add "contents" flag to kernel_read_file hook
module: Call security_kernel_post_load_data()
firmware_loader: Use security_post_load_data()
LSM: Introduce kernel_post_load_data() hook
fs/kernel_read_file: Add file_size output argument
fs/kernel_read_file: Switch buffer size arg to size_t
fs/kernel_read_file: Remove redundant size argument
...
Diffstat (limited to 'drivers/android/binder_alloc.c')
-rw-r--r-- | drivers/android/binder_alloc.c | 57 |
1 files changed, 53 insertions, 4 deletions
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 69609696a843..2f846b7ae8b8 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -338,12 +338,50 @@ static inline struct vm_area_struct *binder_alloc_get_vma( return vma; } +static void debug_low_async_space_locked(struct binder_alloc *alloc, int pid) +{ + /* + * Find the amount and size of buffers allocated by the current caller; + * The idea is that once we cross the threshold, whoever is responsible + * for the low async space is likely to try to send another async txn, + * and at some point we'll catch them in the act. This is more efficient + * than keeping a map per pid. + */ + struct rb_node *n; + struct binder_buffer *buffer; + size_t total_alloc_size = 0; + size_t num_buffers = 0; + + for (n = rb_first(&alloc->allocated_buffers); n != NULL; + n = rb_next(n)) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + if (buffer->pid != pid) + continue; + if (!buffer->async_transaction) + continue; + total_alloc_size += binder_alloc_buffer_size(alloc, buffer) + + sizeof(struct binder_buffer); + num_buffers++; + } + + /* + * Warn if this pid has more than 50 transactions, or more than 50% of + * async space (which is 25% of total buffer size). + */ + if (num_buffers > 50 || total_alloc_size > alloc->buffer_size / 4) { + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: pid %d spamming oneway? %zd buffers allocated for a total size of %zd\n", + alloc->pid, pid, num_buffers, total_alloc_size); + } +} + static struct binder_buffer *binder_alloc_new_buf_locked( struct binder_alloc *alloc, size_t data_size, size_t offsets_size, size_t extra_buffers_size, - int is_async) + int is_async, + int pid) { struct rb_node *n = alloc->free_buffers.rb_node; struct binder_buffer *buffer; @@ -486,11 +524,20 @@ static struct binder_buffer *binder_alloc_new_buf_locked( buffer->offsets_size = offsets_size; buffer->async_transaction = is_async; buffer->extra_buffers_size = extra_buffers_size; + buffer->pid = pid; if (is_async) { alloc->free_async_space -= size + sizeof(struct binder_buffer); binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC, "%d: binder_alloc_buf size %zd async free %zd\n", alloc->pid, size, alloc->free_async_space); + if (alloc->free_async_space < alloc->buffer_size / 10) { + /* + * Start detecting spammers once we have less than 20% + * of async space left (which is less than 10% of total + * buffer size). + */ + debug_low_async_space_locked(alloc, pid); + } } return buffer; @@ -508,6 +555,7 @@ err_alloc_buf_struct_failed: * @offsets_size: user specified buffer offset * @extra_buffers_size: size of extra space for meta-data (eg, security context) * @is_async: buffer for async transaction + * @pid: pid to attribute allocation to (used for debugging) * * Allocate a new buffer given the requested sizes. Returns * the kernel version of the buffer pointer. The size allocated @@ -520,13 +568,14 @@ struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, size_t data_size, size_t offsets_size, size_t extra_buffers_size, - int is_async) + int is_async, + int pid) { struct binder_buffer *buffer; mutex_lock(&alloc->mutex); buffer = binder_alloc_new_buf_locked(alloc, data_size, offsets_size, - extra_buffers_size, is_async); + extra_buffers_size, is_async, pid); mutex_unlock(&alloc->mutex); return buffer; } @@ -652,7 +701,7 @@ static void binder_free_buf_locked(struct binder_alloc *alloc, * @alloc: binder_alloc for this proc * @buffer: kernel pointer to buffer * - * Free the buffer allocated via binder_alloc_new_buffer() + * Free the buffer allocated via binder_alloc_new_buf() */ void binder_alloc_free_buf(struct binder_alloc *alloc, struct binder_buffer *buffer) |