linux-stable.git/drivers/net/ppp, branch v6.7

ppp: limit MRU to 64K

2023-11-13T11:09:20+00:00

ppp_sync_ioctl allows setting device MRU, but does not sanity check
this input.

Limit to a sane upper bound of 64KB.

No implementation I could find generates larger than 64KB frames.
RFC 2823 mentions an upper bound of PPP over SDL of 64KB based on the
16-bit length field. Other protocols will be smaller, such as PPPoE
(9KB jumbo frame) and PPPoA (18190 maximum CPCS-SDU size, RFC 2364).
PPTP and L2TP encapsulate in IP.

Syzbot managed to trigger alloc warning in __alloc_pages:

	if (WARN_ON_ONCE_GFP(order > MAX_ORDER, gfp))

    WARNING: CPU: 1 PID: 37 at mm/page_alloc.c:4544 __alloc_pages+0x3ab/0x4a0 mm/page_alloc.c:4544

    __alloc_skb+0x12b/0x330 net/core/skbuff.c:651
    __netdev_alloc_skb+0x72/0x3f0 net/core/skbuff.c:715
    netdev_alloc_skb include/linux/skbuff.h:3225 [inline]
    dev_alloc_skb include/linux/skbuff.h:3238 [inline]
    ppp_sync_input drivers/net/ppp/ppp_synctty.c:669 [inline]
    ppp_sync_receive+0xff/0x680 drivers/net/ppp/ppp_synctty.c:334
    tty_ldisc_receive_buf+0x14c/0x180 drivers/tty/tty_buffer.c:390
    tty_port_default_receive_buf+0x70/0xb0 drivers/tty/tty_port.c:37
    receive_buf drivers/tty/tty_buffer.c:444 [inline]
    flush_to_ldisc+0x261/0x780 drivers/tty/tty_buffer.c:494
    process_one_work+0x884/0x15c0 kernel/workqueue.c:2630

With call

    ioctl$PPPIOCSMRU1(r1, 0x40047452, &(0x7f0000000100)=0x5e6417a8)

Similar code exists in other drivers that implement ppp_channel_ops
ioctl PPPIOCSMRU. Those might also be in scope. Notably excluded from
this are pppol2tp_ioctl and pppoe_ioctl.

This code goes back to the start of git history.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot+6177e1f90d92583bcc58@syzkaller.appspotmail.com
Signed-off-by: Willem de Bruijn 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller

tty: Fix uninit-value access in ppp_sync_receive()

2023-11-10T11:09:53+00:00

KMSAN reported the following uninit-value access issue:

=====================================================
BUG: KMSAN: uninit-value in ppp_sync_input drivers/net/ppp/ppp_synctty.c:690 [inline]
BUG: KMSAN: uninit-value in ppp_sync_receive+0xdc9/0xe70 drivers/net/ppp/ppp_synctty.c:334
 ppp_sync_input drivers/net/ppp/ppp_synctty.c:690 [inline]
 ppp_sync_receive+0xdc9/0xe70 drivers/net/ppp/ppp_synctty.c:334
 tiocsti+0x328/0x450 drivers/tty/tty_io.c:2295
 tty_ioctl+0x808/0x1920 drivers/tty/tty_io.c:2694
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0x211/0x400 fs/ioctl.c:857
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 __alloc_pages+0x75d/0xe80 mm/page_alloc.c:4591
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __page_frag_cache_refill+0x9a/0x2c0 mm/page_alloc.c:4691
 page_frag_alloc_align+0x91/0x5d0 mm/page_alloc.c:4722
 page_frag_alloc include/linux/gfp.h:322 [inline]
 __netdev_alloc_skb+0x215/0x6d0 net/core/skbuff.c:728
 netdev_alloc_skb include/linux/skbuff.h:3225 [inline]
 dev_alloc_skb include/linux/skbuff.h:3238 [inline]
 ppp_sync_input drivers/net/ppp/ppp_synctty.c:669 [inline]
 ppp_sync_receive+0x237/0xe70 drivers/net/ppp/ppp_synctty.c:334
 tiocsti+0x328/0x450 drivers/tty/tty_io.c:2295
 tty_ioctl+0x808/0x1920 drivers/tty/tty_io.c:2694
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0x211/0x400 fs/ioctl.c:857
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 0 PID: 12950 Comm: syz-executor.1 Not tainted 6.6.0-14500-g1c41041124bd #10
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc38 04/01/2014
=====================================================

ppp_sync_input() checks the first 2 bytes of the data are PPP_ALLSTATIONS
and PPP_UI. However, if the data length is 1 and the first byte is
PPP_ALLSTATIONS, an access to an uninitialized value occurs when checking
PPP_UI. This patch resolves this issue by checking the data length.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Shigeru Yoshida 
Reviewed-by: Simon Horman 
Signed-off-by: David S. Miller

drivers/net/ppp: use standard array-copy-function

2023-11-08T09:40:19+00:00

In ppp_generic.c, memdup_user() is utilized to copy a userspace array.
This is done without an overflow-check, which is, however, not critical
because the multiplicands are an unsigned short and struct sock_filter,
which is currently of size 8.

Regardless, string.h now provides memdup_array_user(), a wrapper for
copying userspace arrays in a standardized manner, which has the
advantage of making it more obvious to the reader that an array is being
copied.
The wrapper additionally performs an obligatory overflow check, saving
the reader the effort of analyzing the potential for overflow, and
making the code a bit more robust in case of future changes to the
multiplicands len * size.

Replace memdup_user() with memdup_array_user().

Suggested-by: Dave Airlie 
Signed-off-by: Philipp Stanner 
Signed-off-by: David S. Miller

net: implement lockless SO_PRIORITY

2023-10-01T18:09:54+00:00

This is a followup of 8bf43be799d4 ("net: annotate data-races
around sk->sk_priority").

sk->sk_priority can be read and written without holding the socket lock.

Signed-off-by: Eric Dumazet 
Reviewed-by: Wenjia Zhang 
Signed-off-by: David S. Miller

Merge tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2023-09-01T16:38:00+00:00

Pull tty/serial driver updates from Greg KH:
 "Here is the big set of tty and serial driver changes for 6.6-rc1.

  Lots of cleanups in here this cycle, and some driver updates. Short
  summary is:

   - Jiri's continued work to make the tty code and apis be a bit more
     sane with regards to modern kernel coding style and types

   - cpm_uart driver updates

   - n_gsm updates and fixes

   - meson driver updates

   - sc16is7xx driver updates

   - 8250 driver updates for different hardware types

   - qcom-geni driver fixes

   - tegra serial driver change

   - stm32 driver updates

   - synclink_gt driver cleanups

   - tty structure size reduction

  All of these have been in linux-next this week with no reported
  issues. The last bit of cleanups from Jiri and the tty structure size
  reduction came in last week, a bit late but as they were just style
  changes and size reductions, I figured they should get into this merge
  cycle so that others can work on top of them with no merge conflicts"

* tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits)
  tty: shrink the size of struct tty_struct by 40 bytes
  tty: n_tty: deduplicate copy code in n_tty_receive_buf_real_raw()
  tty: n_tty: extract ECHO_OP processing to a separate function
  tty: n_tty: unify counts to size_t
  tty: n_tty: use u8 for chars and flags
  tty: n_tty: simplify chars_in_buffer()
  tty: n_tty: remove unsigned char casts from character constants
  tty: n_tty: move newline handling to a separate function
  tty: n_tty: move canon handling to a separate function
  tty: n_tty: use MASK() for masking out size bits
  tty: n_tty: make n_tty_data::num_overrun unsigned
  tty: n_tty: use time_is_before_jiffies() in n_tty_receive_overrun()
  tty: n_tty: use 'num' for writes' counts
  tty: n_tty: use output character directly
  tty: n_tty: make flow of n_tty_receive_buf_common() a bool
  Revert "tty: serial: meson: Add a earlycon for the T7 SoC"
  Documentation: devices.txt: Fix minors for ttyCPM*
  Documentation: devices.txt: Remove ttySIOC*
  Documentation: devices.txt: Remove ttyIOC*
  serial: 8250_bcm7271: improve bcm7271 8250 port
  ...

tty: ldops: unify to u8

2023-08-11T19:12:47+00:00

Some hooks in struct tty_ldisc_ops still reference buffers by 'unsigned
char'. Unify to 'u8' as the rest of the tty layer does.

Signed-off-by: "Jiri Slaby (SUSE)" 
Cc: Marcel Holtmann 
Cc: Johan Hedberg 
Cc: Luiz Augusto von Dentz 
Cc: Dmitry Torokhov 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Krzysztof Kozlowski 
Link: https://lore.kernel.org/r/20230810091510.13006-32-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

tty: use u8 for flags

2023-08-11T19:12:45+00:00

This makes all those 'char's an explicit 'u8'. This is part of the
continuing unification of chars and flags to be consistent u8.

This approaches tty_port_default_receive_buf().

Note that we do not change signedness as we compile with
-funsigned-char.

Signed-off-by: "Jiri Slaby (SUSE)" 
Cc: William Hubbs 
Cc: Chris Brannon 
Cc: Kirk Reiser 
Cc: Samuel Thibault 
Cc: Marcel Holtmann 
Cc: Johan Hedberg 
Cc: Luiz Augusto von Dentz 
Cc: Dmitry Torokhov 
Cc: Arnd Bergmann 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Max Staudt 
Cc: Wolfgang Grandegger 
Cc: Marc Kleine-Budde 
Cc: Dario Binacchi 
Cc: Andreas Koensgen 
Cc: Jeremy Kerr 
Cc: Matt Johnston 
Cc: Krzysztof Kozlowski 
Cc: Liam Girdwood 
Cc: Mark Brown 
Cc: Jaroslav Kysela 
Cc: Takashi Iwai 
Acked-by: Mark Brown 
Link: https://lore.kernel.org/r/20230810091510.13006-18-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

tty: use u8 for chars

2023-08-11T19:12:45+00:00

This makes all those 'unsigned char's an explicit 'u8'. This is part of
the continuing unification of chars and flags to be consistent u8.

This approaches tty_port_default_receive_buf(). Flags to be next.

Signed-off-by: "Jiri Slaby (SUSE)" 
Cc: William Hubbs 
Cc: Chris Brannon 
Cc: Kirk Reiser 
Cc: Samuel Thibault 
Cc: Dmitry Torokhov 
Cc: Arnd Bergmann 
Cc: Max Staudt 
Cc: Wolfgang Grandegger 
Cc: Marc Kleine-Budde 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Dario Binacchi 
Cc: Andreas Koensgen 
Cc: Jeremy Kerr 
Cc: Matt Johnston 
Cc: Liam Girdwood 
Cc: Mark Brown 
Cc: Jaroslav Kysela 
Cc: Takashi Iwai 
Cc: Peter Ujfalusi 
Acked-by: Mark Brown 
Link: https://lore.kernel.org/r/20230810091510.13006-17-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

tty: make tty_ldisc_ops::buf() hooks operate on size_t

2023-08-11T19:12:45+00:00

Count passed to tty_ldisc_ops::receive_buf*(), ::lookahead_buf(), and
returned from ::receive_buf2() is expected to be size_t. So set it to
size_t to unify with the rest of the code.

Signed-off-by: "Jiri Slaby (SUSE)" 
Cc: William Hubbs 
Cc: Chris Brannon 
Cc: Kirk Reiser 
Cc: Samuel Thibault 
Cc: Marcel Holtmann 
Cc: Johan Hedberg 
Cc: Luiz Augusto von Dentz 
Cc: Dmitry Torokhov 
Cc: Arnd Bergmann 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Max Staudt 
Cc: Wolfgang Grandegger 
Cc: Marc Kleine-Budde 
Cc: Dario Binacchi 
Cc: Andreas Koensgen 
Cc: Jeremy Kerr 
Cc: Matt Johnston 
Cc: Krzysztof Kozlowski 
Cc: Liam Girdwood 
Cc: Mark Brown 
Cc: Jaroslav Kysela 
Cc: Takashi Iwai 
Acked-by: Mark Brown 
Link: https://lore.kernel.org/r/20230810091510.13006-16-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

tty: remove dummy tty_ldisc_ops::poll() implementations

2023-08-11T19:12:44+00:00

tty_ldisc_ops::poll() is optional and needs not be provided. It is equal
to returning 0. So remove all those from the code.

Signed-off-by: "Jiri Slaby (SUSE)" 
Cc: Marcel Holtmann 
Cc: Johan Hedberg 
Cc: Luiz Augusto von Dentz 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Krzysztof Kozlowski 
Link: https://lore.kernel.org/r/20230810091510.13006-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman

linux-stable.git/drivers/net/ppp, branch v6.7

ppp: limit MRU to 64K

tty: Fix uninit-value access in ppp_sync_receive()

drivers/net/ppp: use standard array-copy-function

net: implement lockless SO_PRIORITY

Merge tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

tty: ldops: unify to u8

tty: use u8 for flags

tty: use u8 for chars

tty: make tty_ldisc_ops::*buf*() hooks operate on size_t

tty: remove dummy tty_ldisc_ops::poll() implementations

tty: make tty_ldisc_ops::buf() hooks operate on size_t