Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1449889

[PATCH 3.14 44/53] tty/vt/keyboard: fix OOB access in do_compute_shiftstate()

From Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Newsgroups linux.kernel
Subject [PATCH 3.14 44/53] tty/vt/keyboard: fix OOB access in do_compute_shiftstate()
Date 2016-07-25 23:20 +0200
Message-ID <rYVs6-1c6-33@gated-at.bofh.it> (permalink)
References <rYV8K-Pn-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


3.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dmitry Torokhov <dmitry.torokhov@gmail.com>

commit 510cccb5b0c8868a2b302a0ab524da7912da648b upstream.

The size of individual keymap in drivers/tty/vt/keyboard.c is NR_KEYS,
which is currently 256, whereas number of keys/buttons in input device (and
therefor in key_down) is much larger - KEY_CNT - 768, and that can cause
out-of-bound access when we do

	sym = U(key_maps[0][k]);

with large 'k'.

To fix it we should not attempt iterating beyond smaller of NR_KEYS and
KEY_CNT.

Also while at it let's switch to for_each_set_bit() instead of open-coding
it.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/tty/vt/keyboard.c |   30 +++++++++---------------------
 1 file changed, 9 insertions(+), 21 deletions(-)

--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -365,34 +365,22 @@ static void to_utf8(struct vc_data *vc,
 
 static void do_compute_shiftstate(void)
 {
-	unsigned int i, j, k, sym, val;
+	unsigned int k, sym, val;
 
 	shift_state = 0;
 	memset(shift_down, 0, sizeof(shift_down));
 
-	for (i = 0; i < ARRAY_SIZE(key_down); i++) {
-
-		if (!key_down[i])
+	for_each_set_bit(k, key_down, min(NR_KEYS, KEY_CNT)) {
+		sym = U(key_maps[0][k]);
+		if (KTYP(sym) != KT_SHIFT && KTYP(sym) != KT_SLOCK)
 			continue;
 
-		k = i * BITS_PER_LONG;
-
-		for (j = 0; j < BITS_PER_LONG; j++, k++) {
-
-			if (!test_bit(k, key_down))
-				continue;
-
-			sym = U(key_maps[0][k]);
-			if (KTYP(sym) != KT_SHIFT && KTYP(sym) != KT_SLOCK)
-				continue;
-
-			val = KVAL(sym);
-			if (val == KVAL(K_CAPSSHIFT))
-				val = KVAL(K_SHIFT);
+		val = KVAL(sym);
+		if (val == KVAL(K_CAPSSHIFT))
+			val = KVAL(K_SHIFT);
 
-			shift_down[val]++;
-			shift_state |= (1 << val);
-		}
+		shift_down[val]++;
+		shift_state |= BIT(val);
 	}
 }
 

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH 3.14 00/53] 3.14.74-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 25/53] signal: remove warning about using SI_TKILL in rt_[tg]sigqueueinfo Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 16/53] kprobes/x86: Clear TF bit in fault on single-stepping Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 40/53] iio: accel: kxsd9: fix the usage of spi_w8r8() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 39/53] staging: iio: accel: fix error check Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 24/53] nfsd: check permissions when setting ACLs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 03/53] ipmr/ip6mr: Initialize the last assert time of mfc entries. Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 05/53] usb: quirks: Add no-lpm quirk for Acer C120 LED Projector Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 17/53] x86/amd_nb: Fix boot crash on non-AMD systems Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 48/53] scsi: fix race between simultaneous decrements of ->host_failed Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:00 +0200
  [PATCH 3.14 49/53] Fix reconnect to not defer smb3 session reconnect long after socket reconnect Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:10 +0200
  [PATCH 3.14 47/53] ALSA: ctl: Stop notification after disconnection Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:10 +0200
  [PATCH 3.14 36/53] perf/x86: Honor the architectural performance monitoring version Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 52/53] tmpfs: fix regression hang in fallocate undo Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 43/53] iio:ad7266: Fix probe deferral for vref Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 15/53] x86, build: copy ldlinux.c32 to image.iso Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 50/53] xen/acpi: allow xen-acpi-processor driver to load on Xen 4.7 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 31/53] HID: hiddev: validate num_values for HIDIOCGUSAGES, HIDIOCSUSAGES commands Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 13/53] powerpc/tm: Always reclaim in start_thread() for exec() class syscalls Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 41/53] iio:ad7266: Fix broken regulator error handling Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 46/53] ALSA: au88x0: Fix calculation in vortex_wtdma_bufshift() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 45/53] ALSA: dummy: Fix a use-after-free at closing Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 11/53] powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 53/53] s390/seccomp: fix error return for filtered system calls Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 44/53] tty/vt/keyboard: fix OOB access in do_compute_shiftstate() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 12/53] powerpc/pseries: Fix PCI config address for DDW Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 32/53] tracing: Handle NULL formats in hold_module_trace_bprintk_format() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 14/53] USB: EHCI: declare hostpc register as zero-length array Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 37/53] perf/x86: Fix undefined shift on 32-bit kernels Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 29/53] kvm: Fix irq route entries exceeding KVM_MAX_IRQ_ROUTES Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 34/53] drm/radeon: fix asic initialization for virtualized environments Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 51/53] tmpfs: dont undo fallocate past its last page Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 30/53] HID: elo: kill not flush the work Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 23/53] posix_acl: Add set_posix_acl Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 42/53] iio:ad7266: Fix support for optional regulators Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-25 23:20 +0200
  [PATCH 3.14 04/53] net: alx: Work around the DMA RX overflow issue Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 21/53] mm: Export migrate_page_move_mapping and migrate_page_copy Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 22/53] UBIFS: Implement ->migratepage() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 20/53] ARM: 8578/1: mm: ensure pmd_present only checks the valid bit Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 19/53] NFS: Fix another OPEN_DOWNGRADE bug Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 01/53] crypto: ux500 - memmove the right size Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 07/53] usb: musb: Ensure rx reinit occurs for shared_fifo endpoints Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 18/53] make nfs_atomic_open() call d_drop() on all ->open_context() errors. Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 02/53] sit: correct IP protocol used in ipip6_err Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 10/53] IB/mlx4: Properly initialize GRH TClass and FlowLabel in AHs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 28/53] KEYS: potential uninitialized variable Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 09/53] mac80211_hwsim: Add missing check for HWSIM_ATTR_SIGNAL Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  [PATCH 3.14 06/53] usb: musb: Stop bulk endpoint while queue is rotated Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-07-26 00:50 +0200
  Re: [PATCH 3.14 00/53] 3.14.74-stable review Shuah Khan <shuah.kh@samsung.com> - 2016-07-26 04:10 +0200
  Re: [PATCH 3.14 00/53] 3.14.74-stable review Guenter Roeck <linux@roeck-us.net> - 2016-07-26 16:00 +0200

csiph-web