--- /dev/null
+From 5c6f25887963f15492b604dd25cb149c501bbabf Mon Sep 17 00:00:00 2001
+From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Date: Fri, 20 Mar 2020 17:22:58 +0100
+Subject: bpf: Explicitly memset some bpf info structures declared on the stack
+
+From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+commit 5c6f25887963f15492b604dd25cb149c501bbabf upstream.
+
+Trying to initialize a structure with "= {};" will not always clean out
+all padding locations in a structure. So be explicit and call memset to
+initialize everything for a number of bpf information structures that
+are then copied from userspace, sometimes from smaller memory locations
+than the size of the structure.
+
+Reported-by: Daniel Borkmann <daniel@iogearbox.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
+Acked-by: Yonghong Song <yhs@fb.com>
+Link: https://lore.kernel.org/bpf/20200320162258.GA794295@kroah.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ kernel/bpf/syscall.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+--- a/kernel/bpf/syscall.c
++++ b/kernel/bpf/syscall.c
+@@ -1364,7 +1364,7 @@ static int bpf_prog_get_info_by_fd(struc
+ union bpf_attr __user *uattr)
+ {
+ struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
+- struct bpf_prog_info info = {};
++ struct bpf_prog_info info;
+ u32 info_len = attr->info.info_len;
+ char __user *uinsns;
+ u32 ulen;
+@@ -1375,6 +1375,7 @@ static int bpf_prog_get_info_by_fd(struc
+ return err;
+ info_len = min_t(u32, sizeof(info), info_len);
+
++ memset(&info, 0, sizeof(info));
+ if (copy_from_user(&info, uinfo, info_len))
+ return -EFAULT;
+
+@@ -1420,7 +1421,7 @@ static int bpf_map_get_info_by_fd(struct
+ union bpf_attr __user *uattr)
+ {
+ struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
+- struct bpf_map_info info = {};
++ struct bpf_map_info info;
+ u32 info_len = attr->info.info_len;
+ int err;
+
+@@ -1429,6 +1430,7 @@ static int bpf_map_get_info_by_fd(struct
+ return err;
+ info_len = min_t(u32, sizeof(info), info_len);
+
++ memset(&info, 0, sizeof(info));
+ info.type = map->map_type;
+ info.id = map->id;
+ info.key_size = map->key_size;
--- /dev/null
+From 8096f229421f7b22433775e928d506f0342e5907 Mon Sep 17 00:00:00 2001
+From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Date: Fri, 20 Mar 2020 10:48:13 +0100
+Subject: bpf: Explicitly memset the bpf_attr structure
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+commit 8096f229421f7b22433775e928d506f0342e5907 upstream.
+
+For the bpf syscall, we are relying on the compiler to properly zero out
+the bpf_attr union that we copy userspace data into. Unfortunately that
+doesn't always work properly, padding and other oddities might not be
+correctly zeroed, and in some tests odd things have been found when the
+stack is pre-initialized to other values.
+
+Fix this by explicitly memsetting the structure to 0 before using it.
+
+Reported-by: Maciej Żenczykowski <maze@google.com>
+Reported-by: John Stultz <john.stultz@linaro.org>
+Reported-by: Alexander Potapenko <glider@google.com>
+Reported-by: Alistair Delva <adelva@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
+Acked-by: Yonghong Song <yhs@fb.com>
+Link: https://android-review.googlesource.com/c/kernel/common/+/1235490
+Link: https://lore.kernel.org/bpf/20200320094813.GA421650@kroah.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ kernel/bpf/syscall.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+--- a/kernel/bpf/syscall.c
++++ b/kernel/bpf/syscall.c
+@@ -1474,7 +1474,7 @@ static int bpf_obj_get_info_by_fd(const
+
+ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
+ {
+- union bpf_attr attr = {};
++ union bpf_attr attr;
+ int err;
+
+ if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
+@@ -1486,6 +1486,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf
+ size = min_t(u32, size, sizeof(attr));
+
+ /* copy attributes from user space, may be less than sizeof(bpf_attr) */
++ memset(&attr, 0, sizeof(attr));
+ if (copy_from_user(&attr, uattr, size) != 0)
+ return -EFAULT;
+
--- /dev/null
+From 95b31e35239e5e1689e3d965d692a313c71bd8ab Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Georg=20M=C3=BCller?= <georgmueller@gmx.net>
+Date: Mon, 3 Feb 2020 21:11:06 +0100
+Subject: platform/x86: pmc_atom: Add Lex 2I385SW to critclk_systems DMI table
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+From: Georg Müller <georgmueller@gmx.net>
+
+commit 95b31e35239e5e1689e3d965d692a313c71bd8ab upstream.
+
+The Lex 2I385SW board has two Intel I211 ethernet controllers. Without
+this patch, only the first port is usable. The second port fails to
+start with the following message:
+
+ igb: probe of 0000:02:00.0 failed with error -2
+
+Fixes: 648e921888ad ("clk: x86: Stop marking clocks as CLK_IS_CRITICAL")
+Tested-by: Georg Müller <georgmueller@gmx.net>
+Signed-off-by: Georg Müller <georgmueller@gmx.net>
+Reviewed-by: Hans de Goede <hdegoede@redhat.com>
+Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/platform/x86/pmc_atom.c | 8 ++++++++
+ 1 file changed, 8 insertions(+)
+
+--- a/drivers/platform/x86/pmc_atom.c
++++ b/drivers/platform/x86/pmc_atom.c
+@@ -445,6 +445,14 @@ static const struct dmi_system_id critcl
+ },
+ {
+ /* pmc_plt_clk* - are used for ethernet controllers */
++ .ident = "Lex 2I385SW",
++ .matches = {
++ DMI_MATCH(DMI_SYS_VENDOR, "Lex BayTrail"),
++ DMI_MATCH(DMI_PRODUCT_NAME, "2I385SW"),
++ },
++ },
++ {
++ /* pmc_plt_clk* - are used for ethernet controllers */
+ .ident = "Beckhoff CB3163",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Beckhoff Automation"),
media-xirlink_cit-add-missing-descriptor-sanity-checks.patch
mac80211-check-port-authorization-in-the-ieee80211_tx_dequeue-case.patch
mac80211-fix-authentication-with-iwlwifi-mvm.patch
+vt-selection-introduce-vc_is_sel.patch
+vt-ioctl-switch-vt_is_in_use-and-vt_busy-to-inlines.patch
+vt-switch-vt_dont_switch-to-bool.patch
+vt-vt_ioctl-remove-unnecessary-console-allocation-checks.patch
+vt-vt_ioctl-fix-vt_disallocate-freeing-in-use-virtual-console.patch
+vt-vt_ioctl-fix-use-after-free-in-vt_in_use.patch
+platform-x86-pmc_atom-add-lex-2i385sw-to-critclk_systems-dmi-table.patch
+bpf-explicitly-memset-the-bpf_attr-structure.patch
+bpf-explicitly-memset-some-bpf-info-structures-declared-on-the-stack.patch
--- /dev/null
+From e587e8f17433ddb26954f0edf5b2f95c42155ae9 Mon Sep 17 00:00:00 2001
+From: Jiri Slaby <jslaby@suse.cz>
+Date: Wed, 19 Feb 2020 08:39:44 +0100
+Subject: vt: ioctl, switch VT_IS_IN_USE and VT_BUSY to inlines
+
+From: Jiri Slaby <jslaby@suse.cz>
+
+commit e587e8f17433ddb26954f0edf5b2f95c42155ae9 upstream.
+
+These two were macros. Switch them to static inlines, so that it's more
+understandable what they are doing.
+
+Signed-off-by: Jiri Slaby <jslaby@suse.cz>
+Link: https://lore.kernel.org/r/20200219073951.16151-2-jslaby@suse.cz
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/vt/vt_ioctl.c | 29 ++++++++++++++++++++++-------
+ 1 file changed, 22 insertions(+), 7 deletions(-)
+
+--- a/drivers/tty/vt/vt_ioctl.c
++++ b/drivers/tty/vt/vt_ioctl.c
+@@ -40,10 +40,25 @@
+ #include <linux/selection.h>
+
+ char vt_dont_switch;
+-extern struct tty_driver *console_driver;
+
+-#define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
+-#define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_is_sel(vc_cons[i].d))
++static inline bool vt_in_use(unsigned int i)
++{
++ extern struct tty_driver *console_driver;
++
++ return console_driver->ttys[i] && console_driver->ttys[i]->count;
++}
++
++static inline bool vt_busy(int i)
++{
++ if (vt_in_use(i))
++ return true;
++ if (i == fg_console)
++ return true;
++ if (vc_is_sel(vc_cons[i].d))
++ return true;
++
++ return false;
++}
+
+ /*
+ * Console (vt and kd) routines, as defined by USL SVR4 manual, and by
+@@ -289,7 +304,7 @@ static int vt_disallocate(unsigned int v
+ int ret = 0;
+
+ console_lock();
+- if (VT_BUSY(vc_num))
++ if (vt_busy(vc_num))
+ ret = -EBUSY;
+ else if (vc_num)
+ vc = vc_deallocate(vc_num);
+@@ -311,7 +326,7 @@ static void vt_disallocate_all(void)
+
+ console_lock();
+ for (i = 1; i < MAX_NR_CONSOLES; i++)
+- if (!VT_BUSY(i))
++ if (!vt_busy(i))
+ vc[i] = vc_deallocate(i);
+ else
+ vc[i] = NULL;
+@@ -648,7 +663,7 @@ int vt_ioctl(struct tty_struct *tty,
+ state = 1; /* /dev/tty0 is always open */
+ for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
+ ++i, mask <<= 1)
+- if (VT_IS_IN_USE(i))
++ if (vt_in_use(i))
+ state |= mask;
+ ret = put_user(state, &vtstat->v_state);
+ }
+@@ -661,7 +676,7 @@ int vt_ioctl(struct tty_struct *tty,
+ case VT_OPENQRY:
+ /* FIXME: locking ? - but then this is a stupid API */
+ for (i = 0; i < MAX_NR_CONSOLES; ++i)
+- if (! VT_IS_IN_USE(i))
++ if (!vt_in_use(i))
+ break;
+ uival = i < MAX_NR_CONSOLES ? (i+1) : -1;
+ goto setint;
--- /dev/null
+From dce05aa6eec977f1472abed95ccd71276b9a3864 Mon Sep 17 00:00:00 2001
+From: Jiri Slaby <jslaby@suse.cz>
+Date: Wed, 19 Feb 2020 08:39:43 +0100
+Subject: vt: selection, introduce vc_is_sel
+
+From: Jiri Slaby <jslaby@suse.cz>
+
+commit dce05aa6eec977f1472abed95ccd71276b9a3864 upstream.
+
+Avoid global variables (namely sel_cons) by introducing vc_is_sel. It
+checks whether the parameter is the current selection console. This will
+help putting sel_cons to a struct later.
+
+Signed-off-by: Jiri Slaby <jslaby@suse.cz>
+Link: https://lore.kernel.org/r/20200219073951.16151-1-jslaby@suse.cz
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/vt/selection.c | 5 +++++
+ drivers/tty/vt/vt.c | 7 ++++---
+ drivers/tty/vt/vt_ioctl.c | 2 +-
+ include/linux/selection.h | 4 +++-
+ 4 files changed, 13 insertions(+), 5 deletions(-)
+
+--- a/drivers/tty/vt/selection.c
++++ b/drivers/tty/vt/selection.c
+@@ -83,6 +83,11 @@ void clear_selection(void)
+ }
+ }
+
++bool vc_is_sel(struct vc_data *vc)
++{
++ return vc == sel_cons;
++}
++
+ /*
+ * User settable table: what characters are to be considered alphabetic?
+ * 128 bits. Locked by the console lock.
+--- a/drivers/tty/vt/vt.c
++++ b/drivers/tty/vt/vt.c
+@@ -584,8 +584,9 @@ static void hide_softcursor(struct vc_da
+
+ static void hide_cursor(struct vc_data *vc)
+ {
+- if (vc == sel_cons)
++ if (vc_is_sel(vc))
+ clear_selection();
++
+ vc->vc_sw->con_cursor(vc, CM_ERASE);
+ hide_softcursor(vc);
+ }
+@@ -595,7 +596,7 @@ static void set_cursor(struct vc_data *v
+ if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
+ return;
+ if (vc->vc_deccm) {
+- if (vc == sel_cons)
++ if (vc_is_sel(vc))
+ clear_selection();
+ add_softcursor(vc);
+ if ((vc->vc_cursor_type & 0x0f) != 1)
+@@ -873,7 +874,7 @@ static int vc_do_resize(struct tty_struc
+ if (!newscreen)
+ return -ENOMEM;
+
+- if (vc == sel_cons)
++ if (vc_is_sel(vc))
+ clear_selection();
+
+ old_rows = vc->vc_rows;
+--- a/drivers/tty/vt/vt_ioctl.c
++++ b/drivers/tty/vt/vt_ioctl.c
+@@ -43,7 +43,7 @@ char vt_dont_switch;
+ extern struct tty_driver *console_driver;
+
+ #define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
+-#define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_cons[i].d == sel_cons)
++#define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_is_sel(vc_cons[i].d))
+
+ /*
+ * Console (vt and kd) routines, as defined by USL SVR4 manual, and by
+--- a/include/linux/selection.h
++++ b/include/linux/selection.h
+@@ -13,8 +13,8 @@
+
+ struct tty_struct;
+
+-extern struct vc_data *sel_cons;
+ struct tty_struct;
++struct vc_data;
+
+ extern void clear_selection(void);
+ extern int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty);
+@@ -23,6 +23,8 @@ extern int sel_loadlut(char __user *p);
+ extern int mouse_reporting(void);
+ extern void mouse_report(struct tty_struct * tty, int butt, int mrx, int mry);
+
++bool vc_is_sel(struct vc_data *vc);
++
+ extern int console_blanked;
+
+ extern const unsigned char color_table[];
--- /dev/null
+From f400991bf872debffb01c46da882dc97d7e3248e Mon Sep 17 00:00:00 2001
+From: Jiri Slaby <jslaby@suse.cz>
+Date: Wed, 19 Feb 2020 08:39:48 +0100
+Subject: vt: switch vt_dont_switch to bool
+
+From: Jiri Slaby <jslaby@suse.cz>
+
+commit f400991bf872debffb01c46da882dc97d7e3248e upstream.
+
+vt_dont_switch is pure boolean, no need for whole char.
+
+Signed-off-by: Jiri Slaby <jslaby@suse.cz>
+Link: https://lore.kernel.org/r/20200219073951.16151-6-jslaby@suse.cz
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/vt/vt_ioctl.c | 6 +++---
+ include/linux/vt_kern.h | 2 +-
+ 2 files changed, 4 insertions(+), 4 deletions(-)
+
+--- a/drivers/tty/vt/vt_ioctl.c
++++ b/drivers/tty/vt/vt_ioctl.c
+@@ -39,7 +39,7 @@
+ #include <linux/kbd_diacr.h>
+ #include <linux/selection.h>
+
+-char vt_dont_switch;
++bool vt_dont_switch;
+
+ static inline bool vt_in_use(unsigned int i)
+ {
+@@ -1026,12 +1026,12 @@ int vt_ioctl(struct tty_struct *tty,
+ case VT_LOCKSWITCH:
+ if (!capable(CAP_SYS_TTY_CONFIG))
+ return -EPERM;
+- vt_dont_switch = 1;
++ vt_dont_switch = true;
+ break;
+ case VT_UNLOCKSWITCH:
+ if (!capable(CAP_SYS_TTY_CONFIG))
+ return -EPERM;
+- vt_dont_switch = 0;
++ vt_dont_switch = false;
+ break;
+ case VT_GETHIFONTMASK:
+ ret = put_user(vc->vc_hi_font_mask,
+--- a/include/linux/vt_kern.h
++++ b/include/linux/vt_kern.h
+@@ -142,7 +142,7 @@ static inline bool vt_force_oops_output(
+ return false;
+ }
+
+-extern char vt_dont_switch;
++extern bool vt_dont_switch;
+ extern int default_utf8;
+ extern int global_cursor_default;
+
--- /dev/null
+From 7cf64b18b0b96e751178b8d0505d8466ff5a448f Mon Sep 17 00:00:00 2001
+From: Eric Biggers <ebiggers@google.com>
+Date: Sat, 21 Mar 2020 20:43:05 -0700
+Subject: vt: vt_ioctl: fix use-after-free in vt_in_use()
+
+From: Eric Biggers <ebiggers@google.com>
+
+commit 7cf64b18b0b96e751178b8d0505d8466ff5a448f upstream.
+
+vt_in_use() dereferences console_driver->ttys[i] without proper locking.
+This is broken because the tty can be closed and freed concurrently.
+
+We could fix this by using 'READ_ONCE(console_driver->ttys[i]) != NULL'
+and skipping the check of tty_struct::count. But, looking at
+console_driver->ttys[i] isn't really appropriate anyway because even if
+it is NULL the tty can still be in the process of being closed.
+
+Instead, fix it by making vt_in_use() require console_lock() and check
+whether the vt is allocated and has port refcount > 1. This works since
+following the patch "vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use
+virtual console" the port refcount is incremented while the vt is open.
+
+Reproducer (very unreliable, but it worked for me after a few minutes):
+
+ #include <fcntl.h>
+ #include <linux/vt.h>
+
+ int main()
+ {
+ int fd, nproc;
+ struct vt_stat state;
+ char ttyname[16];
+
+ fd = open("/dev/tty10", O_RDONLY);
+ for (nproc = 1; nproc < 8; nproc *= 2)
+ fork();
+ for (;;) {
+ sprintf(ttyname, "/dev/tty%d", rand() % 8);
+ close(open(ttyname, O_RDONLY));
+ ioctl(fd, VT_GETSTATE, &state);
+ }
+ }
+
+KASAN report:
+
+ BUG: KASAN: use-after-free in vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline]
+ BUG: KASAN: use-after-free in vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657
+ Read of size 4 at addr ffff888065722468 by task syz-vt2/132
+
+ CPU: 0 PID: 132 Comm: syz-vt2 Not tainted 5.6.0-rc5-00130-g089b6d3654916 #13
+ Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
+ Call Trace:
+ [...]
+ vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline]
+ vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657
+ tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
+ [...]
+
+ Allocated by task 136:
+ [...]
+ kzalloc include/linux/slab.h:669 [inline]
+ alloc_tty_struct+0x96/0x8a0 drivers/tty/tty_io.c:2982
+ tty_init_dev+0x23/0x350 drivers/tty/tty_io.c:1334
+ tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
+ tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
+ [...]
+
+ Freed by task 41:
+ [...]
+ kfree+0xbf/0x200 mm/slab.c:3757
+ free_tty_struct+0x8d/0xb0 drivers/tty/tty_io.c:177
+ release_one_tty+0x22d/0x2f0 drivers/tty/tty_io.c:1468
+ process_one_work+0x7f1/0x14b0 kernel/workqueue.c:2264
+ worker_thread+0x8b/0xc80 kernel/workqueue.c:2410
+ [...]
+
+Fixes: 4001d7b7fc27 ("vt: push down the tty lock so we can see what is left to tackle")
+Cc: <stable@vger.kernel.org> # v3.4+
+Acked-by: Jiri Slaby <jslaby@suse.cz>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Link: https://lore.kernel.org/r/20200322034305.210082-3-ebiggers@kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/vt/vt_ioctl.c | 16 ++++++++++++----
+ 1 file changed, 12 insertions(+), 4 deletions(-)
+
+--- a/drivers/tty/vt/vt_ioctl.c
++++ b/drivers/tty/vt/vt_ioctl.c
+@@ -43,9 +43,15 @@ bool vt_dont_switch;
+
+ static inline bool vt_in_use(unsigned int i)
+ {
+- extern struct tty_driver *console_driver;
++ const struct vc_data *vc = vc_cons[i].d;
+
+- return console_driver->ttys[i] && console_driver->ttys[i]->count;
++ /*
++ * console_lock must be held to prevent the vc from being deallocated
++ * while we're checking whether it's in-use.
++ */
++ WARN_CONSOLE_UNLOCKED();
++
++ return vc && kref_read(&vc->port.kref) > 1;
+ }
+
+ static inline bool vt_busy(int i)
+@@ -643,15 +649,16 @@ int vt_ioctl(struct tty_struct *tty,
+ struct vt_stat __user *vtstat = up;
+ unsigned short state, mask;
+
+- /* Review: FIXME: Console lock ? */
+ if (put_user(fg_console + 1, &vtstat->v_active))
+ ret = -EFAULT;
+ else {
+ state = 1; /* /dev/tty0 is always open */
++ console_lock(); /* required by vt_in_use() */
+ for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
+ ++i, mask <<= 1)
+ if (vt_in_use(i))
+ state |= mask;
++ console_unlock();
+ ret = put_user(state, &vtstat->v_state);
+ }
+ break;
+@@ -661,10 +668,11 @@ int vt_ioctl(struct tty_struct *tty,
+ * Returns the first available (non-opened) console.
+ */
+ case VT_OPENQRY:
+- /* FIXME: locking ? - but then this is a stupid API */
++ console_lock(); /* required by vt_in_use() */
+ for (i = 0; i < MAX_NR_CONSOLES; ++i)
+ if (!vt_in_use(i))
+ break;
++ console_unlock();
+ uival = i < MAX_NR_CONSOLES ? (i+1) : -1;
+ goto setint;
+
--- /dev/null
+From ca4463bf8438b403596edd0ec961ca0d4fbe0220 Mon Sep 17 00:00:00 2001
+From: Eric Biggers <ebiggers@google.com>
+Date: Sat, 21 Mar 2020 20:43:04 -0700
+Subject: vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
+
+From: Eric Biggers <ebiggers@google.com>
+
+commit ca4463bf8438b403596edd0ec961ca0d4fbe0220 upstream.
+
+The VT_DISALLOCATE ioctl can free a virtual console while tty_release()
+is still running, causing a use-after-free in con_shutdown(). This
+occurs because VT_DISALLOCATE considers a virtual console's
+'struct vc_data' to be unused as soon as the corresponding tty's
+refcount hits 0. But actually it may be still being closed.
+
+Fix this by making vc_data be reference-counted via the embedded
+'struct tty_port'. A newly allocated virtual console has refcount 1.
+Opening it for the first time increments the refcount to 2. Closing it
+for the last time decrements the refcount (in tty_operations::cleanup()
+so that it happens late enough), as does VT_DISALLOCATE.
+
+Reproducer:
+ #include <fcntl.h>
+ #include <linux/vt.h>
+ #include <sys/ioctl.h>
+ #include <unistd.h>
+
+ int main()
+ {
+ if (fork()) {
+ for (;;)
+ close(open("/dev/tty5", O_RDWR));
+ } else {
+ int fd = open("/dev/tty10", O_RDWR);
+
+ for (;;)
+ ioctl(fd, VT_DISALLOCATE, 5);
+ }
+ }
+
+KASAN report:
+ BUG: KASAN: use-after-free in con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
+ Write of size 8 at addr ffff88806a4ec108 by task syz_vt/129
+
+ CPU: 0 PID: 129 Comm: syz_vt Not tainted 5.6.0-rc2 #11
+ Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
+ Call Trace:
+ [...]
+ con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
+ release_tty+0xa8/0x410 drivers/tty/tty_io.c:1514
+ tty_release_struct+0x34/0x50 drivers/tty/tty_io.c:1629
+ tty_release+0x984/0xed0 drivers/tty/tty_io.c:1789
+ [...]
+
+ Allocated by task 129:
+ [...]
+ kzalloc include/linux/slab.h:669 [inline]
+ vc_allocate drivers/tty/vt/vt.c:1085 [inline]
+ vc_allocate+0x1ac/0x680 drivers/tty/vt/vt.c:1066
+ con_install+0x4d/0x3f0 drivers/tty/vt/vt.c:3229
+ tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline]
+ tty_init_dev+0x94/0x350 drivers/tty/tty_io.c:1341
+ tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
+ tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
+ [...]
+
+ Freed by task 130:
+ [...]
+ kfree+0xbf/0x1e0 mm/slab.c:3757
+ vt_disallocate drivers/tty/vt/vt_ioctl.c:300 [inline]
+ vt_ioctl+0x16dc/0x1e30 drivers/tty/vt/vt_ioctl.c:818
+ tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
+ [...]
+
+Fixes: 4001d7b7fc27 ("vt: push down the tty lock so we can see what is left to tackle")
+Cc: <stable@vger.kernel.org> # v3.4+
+Reported-by: syzbot+522643ab5729b0421998@syzkaller.appspotmail.com
+Acked-by: Jiri Slaby <jslaby@suse.cz>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Link: https://lore.kernel.org/r/20200322034305.210082-2-ebiggers@kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/vt/vt.c | 23 ++++++++++++++++++++++-
+ drivers/tty/vt/vt_ioctl.c | 12 ++++--------
+ 2 files changed, 26 insertions(+), 9 deletions(-)
+
+--- a/drivers/tty/vt/vt.c
++++ b/drivers/tty/vt/vt.c
+@@ -751,6 +751,17 @@ static void visual_init(struct vc_data *
+ vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
+ }
+
++static void vc_port_destruct(struct tty_port *port)
++{
++ struct vc_data *vc = container_of(port, struct vc_data, port);
++
++ kfree(vc);
++}
++
++static const struct tty_port_operations vc_port_ops = {
++ .destruct = vc_port_destruct,
++};
++
+ int vc_allocate(unsigned int currcons) /* return 0 on success */
+ {
+ struct vt_notifier_param param;
+@@ -776,6 +787,7 @@ int vc_allocate(unsigned int currcons) /
+
+ vc_cons[currcons].d = vc;
+ tty_port_init(&vc->port);
++ vc->port.ops = &vc_port_ops;
+ INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
+
+ visual_init(vc, currcons, 1);
+@@ -2895,6 +2907,7 @@ static int con_install(struct tty_driver
+
+ tty->driver_data = vc;
+ vc->port.tty = tty;
++ tty_port_get(&vc->port);
+
+ if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
+ tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
+@@ -2930,6 +2943,13 @@ static void con_shutdown(struct tty_stru
+ console_unlock();
+ }
+
++static void con_cleanup(struct tty_struct *tty)
++{
++ struct vc_data *vc = tty->driver_data;
++
++ tty_port_put(&vc->port);
++}
++
+ static int default_color = 7; /* white */
+ static int default_italic_color = 2; // green (ASCII)
+ static int default_underline_color = 3; // cyan (ASCII)
+@@ -3054,7 +3074,8 @@ static const struct tty_operations con_o
+ .throttle = con_throttle,
+ .unthrottle = con_unthrottle,
+ .resize = vt_resize,
+- .shutdown = con_shutdown
++ .shutdown = con_shutdown,
++ .cleanup = con_cleanup,
+ };
+
+ static struct cdev vc0_cdev;
+--- a/drivers/tty/vt/vt_ioctl.c
++++ b/drivers/tty/vt/vt_ioctl.c
+@@ -310,10 +310,8 @@ static int vt_disallocate(unsigned int v
+ vc = vc_deallocate(vc_num);
+ console_unlock();
+
+- if (vc && vc_num >= MIN_NR_CONSOLES) {
+- tty_port_destroy(&vc->port);
+- kfree(vc);
+- }
++ if (vc && vc_num >= MIN_NR_CONSOLES)
++ tty_port_put(&vc->port);
+
+ return ret;
+ }
+@@ -333,10 +331,8 @@ static void vt_disallocate_all(void)
+ console_unlock();
+
+ for (i = 1; i < MAX_NR_CONSOLES; i++) {
+- if (vc[i] && i >= MIN_NR_CONSOLES) {
+- tty_port_destroy(&vc[i]->port);
+- kfree(vc[i]);
+- }
++ if (vc[i] && i >= MIN_NR_CONSOLES)
++ tty_port_put(&vc[i]->port);
+ }
+ }
+
--- /dev/null
+From 1aa6e058dd6cd04471b1f21298270014daf48ac9 Mon Sep 17 00:00:00 2001
+From: Eric Biggers <ebiggers@google.com>
+Date: Mon, 24 Feb 2020 00:03:26 -0800
+Subject: vt: vt_ioctl: remove unnecessary console allocation checks
+
+From: Eric Biggers <ebiggers@google.com>
+
+commit 1aa6e058dd6cd04471b1f21298270014daf48ac9 upstream.
+
+The vc_cons_allocated() checks in vt_ioctl() and vt_compat_ioctl() are
+unnecessary because they can only be reached by calling ioctl() on an
+open tty, which implies the corresponding virtual console is allocated.
+
+And even if the virtual console *could* be freed concurrently, then
+these checks would be broken since they aren't done under console_lock,
+and the vc_data is dereferenced before them anyway.
+
+So, remove these unneeded checks to avoid confusion.
+
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Link: https://lore.kernel.org/r/20200224080326.295046-1-ebiggers@kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/vt/vt_ioctl.c | 21 ++-------------------
+ 1 file changed, 2 insertions(+), 19 deletions(-)
+
+--- a/drivers/tty/vt/vt_ioctl.c
++++ b/drivers/tty/vt/vt_ioctl.c
+@@ -350,22 +350,13 @@ int vt_ioctl(struct tty_struct *tty,
+ {
+ struct vc_data *vc = tty->driver_data;
+ struct console_font_op op; /* used in multiple places here */
+- unsigned int console;
++ unsigned int console = vc->vc_num;
+ unsigned char ucval;
+ unsigned int uival;
+ void __user *up = (void __user *)arg;
+ int i, perm;
+ int ret = 0;
+
+- console = vc->vc_num;
+-
+-
+- if (!vc_cons_allocated(console)) { /* impossible? */
+- ret = -ENOIOCTLCMD;
+- goto out;
+- }
+-
+-
+ /*
+ * To have permissions to do most of the vt ioctls, we either have
+ * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
+@@ -1195,18 +1186,10 @@ long vt_compat_ioctl(struct tty_struct *
+ {
+ struct vc_data *vc = tty->driver_data;
+ struct console_font_op op; /* used in multiple places here */
+- unsigned int console;
+ void __user *up = (void __user *)arg;
+ int perm;
+ int ret = 0;
+
+- console = vc->vc_num;
+-
+- if (!vc_cons_allocated(console)) { /* impossible? */
+- ret = -ENOIOCTLCMD;
+- goto out;
+- }
+-
+ /*
+ * To have permissions to do most of the vt ioctls, we either have
+ * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
+@@ -1266,7 +1249,7 @@ long vt_compat_ioctl(struct tty_struct *
+ arg = (unsigned long)compat_ptr(arg);
+ goto fallback;
+ }
+-out:
++
+ return ret;
+
+ fallback:
projects / thirdparty / kernel / stable-queue.git / commitdiff
