diff options
| author | Srinivasarao P <spathi@codeaurora.org> | 2018-01-09 16:05:02 +0530 |
|---|---|---|
| committer | Srinivasarao P <spathi@codeaurora.org> | 2018-01-18 12:49:58 +0530 |
| commit | 2d309c994df3624f59114edea6c03dd7cf3f334d (patch) | |
| tree | dc435837f02d89571f8139262e796e46fa91f228 /kernel/kcov.c | |
| parent | dd4f1e35fa5f5a452d34e1fcc681472f2011f93d (diff) | |
| parent | 79f138ac8c951ea1a06df9c869d16cc983613ac9 (diff) | |
Merge android-4.4.107 (79f138a) into msm-4.4
* refs/heads/tmp-79f138a
Linux 4.4.107
ath9k: fix tx99 potential info leak
IB/ipoib: Grab rtnl lock on heavy flush when calling ndo_open/stop
RDMA/cma: Avoid triggering undefined behavior
macvlan: Only deliver one copy of the frame to the macvlan interface
udf: Avoid overflow when session starts at large offset
scsi: bfa: integer overflow in debugfs
scsi: sd: change allow_restart to bool in sysfs interface
scsi: sd: change manage_start_stop to bool in sysfs interface
vt6655: Fix a possible sleep-in-atomic bug in vt6655_suspend
scsi: scsi_devinfo: Add REPORTLUN2 to EMC SYMMETRIX blacklist entry
raid5: Set R5_Expanded on parity devices as well as data.
pinctrl: adi2: Fix Kconfig build problem
usb: musb: da8xx: fix babble condition handling
tty fix oops when rmmod 8250
powerpc/perf/hv-24x7: Fix incorrect comparison in memord
scsi: hpsa: destroy sas transport properties before scsi_host
scsi: hpsa: cleanup sas_phy structures in sysfs when unloading
PCI: Detach driver before procfs & sysfs teardown on device remove
xfs: fix incorrect extent state in xfs_bmap_add_extent_unwritten_real
xfs: fix log block underflow during recovery cycle verification
l2tp: cleanup l2tp_tunnel_delete calls
bcache: fix wrong cache_misses statistics
bcache: explicitly destroy mutex while exiting
GFS2: Take inode off order_write list when setting jdata flag
thermal/drivers/step_wise: Fix temperature regulation misbehavior
ppp: Destroy the mutex when cleanup
clk: tegra: Fix cclk_lp divisor register
clk: imx6: refine hdmi_isfr's parent to make HDMI work on i.MX6 SoCs w/o VPU
clk: mediatek: add the option for determining PLL source clock
mm: Handle 0 flags in _calc_vm_trans() macro
crypto: tcrypt - fix buffer lengths in test_aead_speed()
arm-ccn: perf: Prevent module unload while PMU is in use
target/file: Do not return error for UNMAP if length is zero
target:fix condition return in core_pr_dump_initiator_port()
iscsi-target: fix memory leak in lio_target_tiqn_addtpg()
target/iscsi: Fix a race condition in iscsit_add_reject_from_cmd()
powerpc/ipic: Fix status get and status clear
powerpc/opal: Fix EBUSY bug in acquiring tokens
netfilter: ipvs: Fix inappropriate output of procfs
powerpc/powernv/cpufreq: Fix the frequency read by /proc/cpuinfo
PCI/PME: Handle invalid data when reading Root Status
dmaengine: ti-dma-crossbar: Correct am335x/am43xx mux value type
rtc: pcf8563: fix output clock rate
video: fbdev: au1200fb: Return an error code if a memory allocation fails
video: fbdev: au1200fb: Release some resources if a memory allocation fails
video: udlfb: Fix read EDID timeout
fbdev: controlfb: Add missing modes to fix out of bounds access
sfc: don't warn on successful change of MAC
target: fix race during implicit transition work flushes
target: fix ALUA transition timeout handling
target: Use system workqueue for ALUA transitions
btrfs: add missing memset while reading compressed inline extents
NFSv4.1 respect server's max size in CREATE_SESSION
efi/esrt: Cleanup bad memory map log messages
perf symbols: Fix symbols__fixup_end heuristic for corner cases
net/mlx4_core: Avoid delays during VF driver device shutdown
afs: Fix afs_kill_pages()
afs: Fix page leak in afs_write_begin()
afs: Populate and use client modification time
afs: Fix the maths in afs_fs_store_data()
afs: Prevent callback expiry timer overflow
afs: Migrate vlocation fields to 64-bit
afs: Flush outstanding writes when an fd is closed
afs: Adjust mode bits processing
afs: Populate group ID from vnode status
afs: Fix missing put_page()
drm/radeon: reinstate oland workaround for sclk
mmc: mediatek: Fixed bug where clock frequency could be set wrong
sched/deadline: Use deadline instead of period when calculating overflow
sched/deadline: Throttle a constrained deadline task activated after the deadline
sched/deadline: Make sure the replenishment timer fires in the next period
drm/radeon/si: add dpm quirk for Oland
fjes: Fix wrong netdevice feature flags
scsi: hpsa: limit outstanding rescans
scsi: hpsa: update check for logical volume status
openrisc: fix issue handling 8 byte get_user calls
intel_th: pci: Add Gemini Lake support
mlxsw: reg: Fix SPVMLR max record count
mlxsw: reg: Fix SPVM max record count
net: Resend IGMP memberships upon peer notification.
dmaengine: Fix array index out of bounds warning in __get_unmap_pool()
net: wimax/i2400m: fix NULL-deref at probe
writeback: fix memory leak in wb_queue_work()
netfilter: bridge: honor frag_max_size when refragmenting
drm/omap: fix dmabuf mmap for dma_alloc'ed buffers
Input: i8042 - add TUXEDO BU1406 (N24_25BU) to the nomux list
NFSD: fix nfsd_reset_versions for NFSv4.
NFSD: fix nfsd_minorversion(.., NFSD_AVAIL)
net: bcmgenet: Power up the internal PHY before probing the MII
net: bcmgenet: power down internal phy if open or resume fails
net: bcmgenet: reserved phy revisions must be checked first
net: bcmgenet: correct MIB access of UniMAC RUNT counters
net: bcmgenet: correct the RBUF_OVFL_CNT and RBUF_ERR_CNT MIB values
net: initialize msg.msg_flags in recvfrom
userfaultfd: selftest: vm: allow to build in vm/ directory
userfaultfd: shmem: __do_fault requires VM_FAULT_NOPAGE
md-cluster: free md_cluster_info if node leave cluster
usb: phy: isp1301: Add OF device ID table
mac80211: Fix addition of mesh configuration element
KEYS: add missing permission check for request_key() destination
ext4: fix crash when a directory's i_size is too small
ext4: fix fdatasync(2) after fallocate(2) operation
dmaengine: dmatest: move callback wait queue to thread context
sched/rt: Do not pull from current CPU if only one CPU to pull
xhci: Don't add a virt_dev to the devs array before it's fully allocated
Bluetooth: btusb: driver to enable the usb-wakeup feature
ceph: drop negative child dentries before try pruning inode's alias
usbip: fix stub_send_ret_submit() vulnerability to null transfer_buffer
USB: core: prevent malicious bNumInterfaces overflow
USB: uas and storage: Add US_FL_BROKEN_FUA for another JMicron JMS567 ID
tracing: Allocate mask_str buffer dynamically
autofs: fix careless error in recent commit
crypto: salsa20 - fix blkcipher_walk API usage
crypto: hmac - require that the underlying hash algorithm is unkeyed
UPSTREAM: arm64: setup: introduce kaslr_offset()
UPSTREAM: kcov: fix comparison callback signature
UPSTREAM: kcov: support comparison operands collection
UPSTREAM: kcov: remove pointless current != NULL check
UPSTREAM: kcov: support compat processes
UPSTREAM: kcov: simplify interrupt check
UPSTREAM: kcov: make kcov work properly with KASLR enabled
UPSTREAM: kcov: add more missing includes
UPSTREAM: kcov: add missing #include <linux/sched.h>
UPSTREAM: kcov: properly check if we are in an interrupt
UPSTREAM: kcov: don't profile branches in kcov
UPSTREAM: kcov: don't trace the code coverage code
BACKPORT: kernel: add kcov code coverage
Conflicts:
Makefile
mm/kasan/Makefile
scripts/Makefile.lib
Change-Id: Ic19953706ea2e700621b0ba94d1c90bbffa4f471
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
Diffstat (limited to 'kernel/kcov.c')
| -rw-r--r-- | kernel/kcov.c | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/kernel/kcov.c b/kernel/kcov.c new file mode 100644 index 000000000000..5813e9375a93 --- /dev/null +++ b/kernel/kcov.c @@ -0,0 +1,431 @@ +#define pr_fmt(fmt) "kcov: " fmt + +#define DISABLE_BRANCH_PROFILING +#include <linux/atomic.h> +#include <linux/compiler.h> +#include <linux/errno.h> +#include <linux/export.h> +#include <linux/types.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/preempt.h> +#include <linux/printk.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/vmalloc.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> +#include <linux/kcov.h> +#include <asm/setup.h> + +/* Number of 64-bit words written per one comparison: */ +#define KCOV_WORDS_PER_CMP 4 + +/* + * kcov descriptor (one per opened debugfs file). + * State transitions of the descriptor: + * - initial state after open() + * - then there must be a single ioctl(KCOV_INIT_TRACE) call + * - then, mmap() call (several calls are allowed but not useful) + * - then, ioctl(KCOV_ENABLE, arg), where arg is + * KCOV_TRACE_PC - to trace only the PCs + * or + * KCOV_TRACE_CMP - to trace only the comparison operands + * - then, ioctl(KCOV_DISABLE) to disable the task. + * Enabling/disabling ioctls can be repeated (only one task a time allowed). + */ +struct kcov { + /* + * Reference counter. We keep one for: + * - opened file descriptor + * - task with enabled coverage (we can't unwire it from another task) + */ + atomic_t refcount; + /* The lock protects mode, size, area and t. */ + spinlock_t lock; + enum kcov_mode mode; + /* Size of arena (in long's for KCOV_MODE_TRACE). */ + unsigned size; + /* Coverage buffer shared with user space. */ + void *area; + /* Task for which we collect coverage, or NULL. */ + struct task_struct *t; +}; + +static bool check_kcov_mode(enum kcov_mode needed_mode, struct task_struct *t) +{ + enum kcov_mode mode; + + /* + * We are interested in code coverage as a function of a syscall inputs, + * so we ignore code executed in interrupts. + */ + if (!in_task()) + return false; + mode = READ_ONCE(t->kcov_mode); + /* + * There is some code that runs in interrupts but for which + * in_interrupt() returns false (e.g. preempt_schedule_irq()). + * READ_ONCE()/barrier() effectively provides load-acquire wrt + * interrupts, there are paired barrier()/WRITE_ONCE() in + * kcov_ioctl_locked(). + */ + barrier(); + return mode == needed_mode; +} + +static unsigned long canonicalize_ip(unsigned long ip) +{ +#ifdef CONFIG_RANDOMIZE_BASE + ip -= kaslr_offset(); +#endif + return ip; +} + +/* + * Entry point from instrumented code. + * This is called once per basic-block/edge. + */ +void notrace __sanitizer_cov_trace_pc(void) +{ + struct task_struct *t; + unsigned long *area; + unsigned long ip = canonicalize_ip(_RET_IP_); + unsigned long pos; + + t = current; + if (!check_kcov_mode(KCOV_MODE_TRACE_PC, t)) + return; + + area = t->kcov_area; + /* The first 64-bit word is the number of subsequent PCs. */ + pos = READ_ONCE(area[0]) + 1; + if (likely(pos < t->kcov_size)) { + area[pos] = ip; + WRITE_ONCE(area[0], pos); + } +} +EXPORT_SYMBOL(__sanitizer_cov_trace_pc); + +#ifdef CONFIG_KCOV_ENABLE_COMPARISONS +static void write_comp_data(u64 type, u64 arg1, u64 arg2, u64 ip) +{ + struct task_struct *t; + u64 *area; + u64 count, start_index, end_pos, max_pos; + + t = current; + if (!check_kcov_mode(KCOV_MODE_TRACE_CMP, t)) + return; + + ip = canonicalize_ip(ip); + + /* + * We write all comparison arguments and types as u64. + * The buffer was allocated for t->kcov_size unsigned longs. + */ + area = (u64 *)t->kcov_area; + max_pos = t->kcov_size * sizeof(unsigned long); + + count = READ_ONCE(area[0]); + + /* Every record is KCOV_WORDS_PER_CMP 64-bit words. */ + start_index = 1 + count * KCOV_WORDS_PER_CMP; + end_pos = (start_index + KCOV_WORDS_PER_CMP) * sizeof(u64); + if (likely(end_pos <= max_pos)) { + area[start_index] = type; + area[start_index + 1] = arg1; + area[start_index + 2] = arg2; + area[start_index + 3] = ip; + WRITE_ONCE(area[0], count + 1); + } +} + +void notrace __sanitizer_cov_trace_cmp1(u8 arg1, u8 arg2) +{ + write_comp_data(KCOV_CMP_SIZE(0), arg1, arg2, _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_cmp1); + +void notrace __sanitizer_cov_trace_cmp2(u16 arg1, u16 arg2) +{ + write_comp_data(KCOV_CMP_SIZE(1), arg1, arg2, _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_cmp2); + +void notrace __sanitizer_cov_trace_cmp4(u32 arg1, u32 arg2) +{ + write_comp_data(KCOV_CMP_SIZE(2), arg1, arg2, _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_cmp4); + +void notrace __sanitizer_cov_trace_cmp8(u64 arg1, u64 arg2) +{ + write_comp_data(KCOV_CMP_SIZE(3), arg1, arg2, _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_cmp8); + +void notrace __sanitizer_cov_trace_const_cmp1(u8 arg1, u8 arg2) +{ + write_comp_data(KCOV_CMP_SIZE(0) | KCOV_CMP_CONST, arg1, arg2, + _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_const_cmp1); + +void notrace __sanitizer_cov_trace_const_cmp2(u16 arg1, u16 arg2) +{ + write_comp_data(KCOV_CMP_SIZE(1) | KCOV_CMP_CONST, arg1, arg2, + _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_const_cmp2); + +void notrace __sanitizer_cov_trace_const_cmp4(u32 arg1, u32 arg2) +{ + write_comp_data(KCOV_CMP_SIZE(2) | KCOV_CMP_CONST, arg1, arg2, + _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_const_cmp4); + +void notrace __sanitizer_cov_trace_const_cmp8(u64 arg1, u64 arg2) +{ + write_comp_data(KCOV_CMP_SIZE(3) | KCOV_CMP_CONST, arg1, arg2, + _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_const_cmp8); + +void notrace __sanitizer_cov_trace_switch(u64 val, u64 *cases) +{ + u64 i; + u64 count = cases[0]; + u64 size = cases[1]; + u64 type = KCOV_CMP_CONST; + + switch (size) { + case 8: + type |= KCOV_CMP_SIZE(0); + break; + case 16: + type |= KCOV_CMP_SIZE(1); + break; + case 32: + type |= KCOV_CMP_SIZE(2); + break; + case 64: + type |= KCOV_CMP_SIZE(3); + break; + default: + return; + } + for (i = 0; i < count; i++) + write_comp_data(type, cases[i + 2], val, _RET_IP_); +} +EXPORT_SYMBOL(__sanitizer_cov_trace_switch); +#endif /* ifdef CONFIG_KCOV_ENABLE_COMPARISONS */ + +static void kcov_get(struct kcov *kcov) +{ + atomic_inc(&kcov->refcount); +} + +static void kcov_put(struct kcov *kcov) +{ + if (atomic_dec_and_test(&kcov->refcount)) { + vfree(kcov->area); + kfree(kcov); + } +} + +void kcov_task_init(struct task_struct *t) +{ + t->kcov_mode = KCOV_MODE_DISABLED; + t->kcov_size = 0; + t->kcov_area = NULL; + t->kcov = NULL; +} + +void kcov_task_exit(struct task_struct *t) +{ + struct kcov *kcov; + + kcov = t->kcov; + if (kcov == NULL) + return; + spin_lock(&kcov->lock); + if (WARN_ON(kcov->t != t)) { + spin_unlock(&kcov->lock); + return; + } + /* Just to not leave dangling references behind. */ + kcov_task_init(t); + kcov->t = NULL; + kcov->mode = KCOV_MODE_INIT; + spin_unlock(&kcov->lock); + kcov_put(kcov); +} + +static int kcov_mmap(struct file *filep, struct vm_area_struct *vma) +{ + int res = 0; + void *area; + struct kcov *kcov = vma->vm_file->private_data; + unsigned long size, off; + struct page *page; + + area = vmalloc_user(vma->vm_end - vma->vm_start); + if (!area) + return -ENOMEM; + + spin_lock(&kcov->lock); + size = kcov->size * sizeof(unsigned long); + if (kcov->mode != KCOV_MODE_INIT || vma->vm_pgoff != 0 || + vma->vm_end - vma->vm_start != size) { + res = -EINVAL; + goto exit; + } + if (!kcov->area) { + kcov->area = area; + vma->vm_flags |= VM_DONTEXPAND; + spin_unlock(&kcov->lock); + for (off = 0; off < size; off += PAGE_SIZE) { + page = vmalloc_to_page(kcov->area + off); + if (vm_insert_page(vma, vma->vm_start + off, page)) + WARN_ONCE(1, "vm_insert_page() failed"); + } + return 0; + } +exit: + spin_unlock(&kcov->lock); + vfree(area); + return res; +} + +static int kcov_open(struct inode *inode, struct file *filep) +{ + struct kcov *kcov; + + kcov = kzalloc(sizeof(*kcov), GFP_KERNEL); + if (!kcov) + return -ENOMEM; + kcov->mode = KCOV_MODE_DISABLED; + atomic_set(&kcov->refcount, 1); + spin_lock_init(&kcov->lock); + filep->private_data = kcov; + return nonseekable_open(inode, filep); +} + +static int kcov_close(struct inode *inode, struct file *filep) +{ + kcov_put(filep->private_data); + return 0; +} + +static int kcov_ioctl_locked(struct kcov *kcov, unsigned int cmd, + unsigned long arg) +{ + struct task_struct *t; + unsigned long size, unused; + + switch (cmd) { + case KCOV_INIT_TRACE: + /* + * Enable kcov in trace mode and setup buffer size. + * Must happen before anything else. + */ + if (kcov->mode != KCOV_MODE_DISABLED) + return -EBUSY; + /* + * Size must be at least 2 to hold current position and one PC. + * Later we allocate size * sizeof(unsigned long) memory, + * that must not overflow. + */ + size = arg; + if (size < 2 || size > INT_MAX / sizeof(unsigned long)) + return -EINVAL; + kcov->size = size; + kcov->mode = KCOV_MODE_INIT; + return 0; + case KCOV_ENABLE: + /* + * Enable coverage for the current task. + * At this point user must have been enabled trace mode, + * and mmapped the file. Coverage collection is disabled only + * at task exit or voluntary by KCOV_DISABLE. After that it can + * be enabled for another task. + */ + if (kcov->mode != KCOV_MODE_INIT || !kcov->area) + return -EINVAL; + if (kcov->t != NULL) + return -EBUSY; + if (arg == KCOV_TRACE_PC) + kcov->mode = KCOV_MODE_TRACE_PC; + else if (arg == KCOV_TRACE_CMP) +#ifdef CONFIG_KCOV_ENABLE_COMPARISONS + kcov->mode = KCOV_MODE_TRACE_CMP; +#else + return -ENOTSUPP; +#endif + else + return -EINVAL; + t = current; + /* Cache in task struct for performance. */ + t->kcov_size = kcov->size; + t->kcov_area = kcov->area; + /* See comment in check_kcov_mode(). */ + barrier(); + WRITE_ONCE(t->kcov_mode, kcov->mode); + t->kcov = kcov; + kcov->t = t; + /* This is put either in kcov_task_exit() or in KCOV_DISABLE. */ + kcov_get(kcov); + return 0; + case KCOV_DISABLE: + /* Disable coverage for the current task. */ + unused = arg; + if (unused != 0 || current->kcov != kcov) + return -EINVAL; + t = current; + if (WARN_ON(kcov->t != t)) + return -EINVAL; + kcov_task_init(t); + kcov->t = NULL; + kcov->mode = KCOV_MODE_INIT; + kcov_put(kcov); + return 0; + default: + return -ENOTTY; + } +} + +static long kcov_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) +{ + struct kcov *kcov; + int res; + + kcov = filep->private_data; + spin_lock(&kcov->lock); + res = kcov_ioctl_locked(kcov, cmd, arg); + spin_unlock(&kcov->lock); + return res; +} + +static const struct file_operations kcov_fops = { + .open = kcov_open, + .unlocked_ioctl = kcov_ioctl, + .compat_ioctl = kcov_ioctl, + .mmap = kcov_mmap, + .release = kcov_close, +}; + +static int __init kcov_init(void) +{ + if (!debugfs_create_file("kcov", 0600, NULL, NULL, &kcov_fops)) { + pr_err("failed to create kcov in debugfs\n"); + return -ENOMEM; + } + return 0; +} + +device_initcall(kcov_init); |
