linux-dev/drivers/net/hamradio, branch master

hamradio: fix issue of dev reference count leakage in bpq_device_event()

2022-11-07T09:32:28Z

When following tests are performed, it will cause dev reference counting leakage. a)ip link add bond2 type bond mode balance-rr b)ip link set bond2 up c)ifenslave -f bond2 rose1 d)ip link del bond2 When new bond device is created, the default type of the bond device is ether. And the bond device is up, bpq_device_event() receives the message and creates a new bpq device. In this case, the reference count value of dev is hold once. But after "ifenslave -f bond2 rose1" command is executed, the type of the bond device is changed to rose. When the bond device is unregistered, bpq_device_event() will not put the dev reference count. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Zhengchao Shao Signed-off-by: David S. Miller

treewide: use get_random_{u8,u16}() when possible, part 1

2022-10-11T23:42:58Z

Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value, simply use the get_random_{u8,u16}() functions, which are faster than wasting the additional bytes from a 32-bit value. This was done mechanically with this coccinelle script: @@ expression E; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u16; typedef __be16; typedef __le16; typedef u8; @@ ( - (get_random_u32() & 0xffff) + get_random_u16() | - (get_random_u32() & 0xff) + get_random_u8() | - (get_random_u32() % 65536) + get_random_u16() | - (get_random_u32() % 256) + get_random_u8() | - (get_random_u32() >> 16) + get_random_u16() | - (get_random_u32() >> 24) + get_random_u8() | - (u16)get_random_u32() + get_random_u16() | - (u8)get_random_u32() + get_random_u8() | - (__be16)get_random_u32() + (__be16)get_random_u16() | - (__le16)get_random_u32() + (__le16)get_random_u16() | - prandom_u32_max(65536) + get_random_u16() | - prandom_u32_max(256) + get_random_u8() | - E->inet_id = get_random_u32() + E->inet_id = get_random_u16() ) @@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u16; identifier v; @@ - u16 v = get_random_u32(); + u16 v = get_random_u16(); @@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u8; identifier v; @@ - u8 v = get_random_u32(); + u8 v = get_random_u8(); @@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u16; u16 v; @@ - v = get_random_u32(); + v = get_random_u16(); @@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u8; u8 v; @@ - v = get_random_u32(); + v = get_random_u8(); // Find a potential literal @literal_mask@ expression LITERAL; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; position p; @@ ((T)get_random_u32()@p & (LITERAL)) // Examine limits @script:python add_one@ literal << literal_mask.LITERAL; RESULT; @@ value = None if literal.startswith('0x'): value = int(literal, 16) elif literal[0] in '123456789': value = int(literal, 10) if value is None: print("I don't know how to handle %s" % (literal)) cocci.include_match(False) elif value < 256: coccinelle.RESULT = cocci.make_ident("get_random_u8") elif value < 65536: coccinelle.RESULT = cocci.make_ident("get_random_u16") else: print("Skipping large mask of %s" % (literal)) cocci.include_match(False) // Replace the literal mask with the calculated result. @plus_one@ expression literal_mask.LITERAL; position literal_mask.p; identifier add_one.RESULT; identifier FUNC; @@ - (FUNC()@p & (LITERAL)) + (RESULT() & LITERAL) Reviewed-by: Greg Kroah-Hartman Reviewed-by: Kees Cook Reviewed-by: Yury Norov Acked-by: Jakub Kicinski Acked-by: Toke Høiland-Jørgensen # for sch_cake Signed-off-by: Jason A. Donenfeld

treewide: use prandom_u32_max() when possible, part 1

2022-10-11T23:42:55Z

Rather than incurring a division or requesting too many random bytes for the given range, use the prandom_u32_max() function, which only takes the minimum required bytes from the RNG and avoids divisions. This was done mechanically with this coccinelle script: @basic@ expression E; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u64; @@ ( - ((T)get_random_u32() % (E)) + prandom_u32_max(E) | - ((T)get_random_u32() & ((E) - 1)) + prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2) | - ((u64)(E) * get_random_u32() >> 32) + prandom_u32_max(E) | - ((T)get_random_u32() & ~PAGE_MASK) + prandom_u32_max(PAGE_SIZE) ) @multi_line@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; identifier RAND; expression E; @@ - RAND = get_random_u32(); ... when != RAND - RAND %= (E); + RAND = prandom_u32_max(E); // Find a potential literal @literal_mask@ expression LITERAL; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; position p; @@ ((T)get_random_u32()@p & (LITERAL)) // Add one to the literal. @script:python add_one@ literal << literal_mask.LITERAL; RESULT; @@ value = None if literal.startswith('0x'): value = int(literal, 16) elif literal[0] in '123456789': value = int(literal, 10) if value is None: print("I don't know how to handle %s" % (literal)) cocci.include_match(False) elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1: print("Skipping 0x%x for cleanup elsewhere" % (value)) cocci.include_match(False) elif value & (value + 1) != 0: print("Skipping 0x%x because it's not a power of two minus one" % (value)) cocci.include_match(False) elif literal.startswith('0x'): coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1)) else: coccinelle.RESULT = cocci.make_expr("%d" % (value + 1)) // Replace the literal mask with the calculated result. @plus_one@ expression literal_mask.LITERAL; position literal_mask.p; expression add_one.RESULT; identifier FUNC; @@ - (FUNC()@p & (LITERAL)) + prandom_u32_max(RESULT) @collapse_ret@ type T; identifier VAR; expression E; @@ { - T VAR; - VAR = (E); - return VAR; + return E; } @drop_var@ type T; identifier VAR; @@ { - T VAR; ... when != VAR } Reviewed-by: Greg Kroah-Hartman Reviewed-by: Kees Cook Reviewed-by: Yury Norov Reviewed-by: KP Singh Reviewed-by: Jan Kara # for ext4 and sbitmap Reviewed-by: Christoph Böhmwalder # for drbd Acked-by: Jakub Kicinski Acked-by: Heiko Carstens # for s390 Acked-by: Ulf Hansson # for mmc Acked-by: Darrick J. Wong # for xfs Signed-off-by: Jason A. Donenfeld

net: move from strlcpy with unused retval to strscpy

2022-08-31T21:11:07Z

Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang Acked-by: Marc Kleine-Budde # for CAN Link: https://lore.kernel.org/r/20220830201457.7984-1-wsa+renesas@sang-engineering.com Signed-off-by: Jakub Kicinski

hamradio: 6pack: fix array-index-out-of-bounds in decode_std_command()

2022-06-17T10:39:46Z

Hulk Robot reports incorrect sp->rx_count_cooked value in decode_std_command(). This should be caused by the subtracting from sp->rx_count_cooked before. It seems that sp->rx_count_cooked value is changed to 0, which bypassed the previous judgment. The situation is shown below: (Thread 1) | (Thread 2) decode_std_command() | resync_tnc() ... | if (rest == 2) | sp->rx_count_cooked -= 2; | else if (rest == 3) | ... | sp->rx_count_cooked = 0; sp->rx_count_cooked -= 1; | for (i = 0; i < sp->rx_count_cooked; i++) // report error checksum += sp->cooked_buf[i]; sp->rx_count_cooked is a shared variable but is not protected by a lock. The same applies to sp->rx_count. This patch adds a lock to fix the bug. The fail log is shown below: ======================================================================= UBSAN: array-index-out-of-bounds in drivers/net/hamradio/6pack.c:925:31 index 400 is out of range for type 'unsigned char [400]' CPU: 3 PID: 7433 Comm: kworker/u10:1 Not tainted 5.18.0-rc5-00163-g4b97bac0756a #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Workqueue: events_unbound flush_to_ldisc Call Trace: dump_stack_lvl+0xcd/0x134 ubsan_epilogue+0xb/0x50 __ubsan_handle_out_of_bounds.cold+0x62/0x6c sixpack_receive_buf+0xfda/0x1330 tty_ldisc_receive_buf+0x13e/0x180 tty_port_default_receive_buf+0x6d/0xa0 flush_to_ldisc+0x213/0x3f0 process_one_work+0x98f/0x1620 worker_thread+0x665/0x1080 kthread+0x2e9/0x3a0 ret_from_fork+0x1f/0x30 ... Reported-by: Hulk Robot Signed-off-by: Xu Jia Signed-off-by: David S. Miller

net: hamradio: remove support for DMA SCC devices

2022-04-27T11:22:56Z

Another incarnation of Z8530, looks like? Again, no real changes in the git history, and it needs VIRT_TO_BUS. Unlikely to have users, let's spend less time refactoring dead code... Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

hamradio: Fix wrong assignment of 'bbc->cfg.loopback'

2022-03-17T02:17:49Z

In file hamradio/baycom_epp.c, the baycom_setmode interface, there is a problem with improper use of strstr. Suppose that when modestr="noloopback", both conditions which are 'strstr(modestr,"noloopback")' and 'strstr(modestr,"loopback")' will be true(not NULL), this lead the bc->cfg.loopback variable will be first assigned to 0, and then reassigned to 1. This will cause 'bc->cfg.loopback = 0' will never take effect. That obviously violates the logic of the code, so adjust the order of their execution to solve the problem. Signed-off-by: Meng Tang Reviewed-by: Dan Carpenter Link: https://lore.kernel.org/r/20220315074851.6456-1-tangmeng@uniontech.com Signed-off-by: Jakub Kicinski

net: hamradio: fix compliation error

2022-03-02T17:47:38Z

add missing ")" which caused by previous commit. Fixes: 61c4fb9c4d09 ("net: hamradio: use time_is_after_jiffies() instead of open coding it") Link: https://lore.kernel.org/all/1646018012-61129-1-git-send-email-wangqing@vivo.com/ Signed-off-by: Wang Qing Link: https://lore.kernel.org/r/1646203277-83159-1-git-send-email-wangqing@vivo.com Signed-off-by: Jakub Kicinski

net: hamradio: use time_is_after_jiffies() instead of open coding it

2022-02-28T13:21:31Z

Use the helper function time_is_{before,after}_jiffies() to improve code readability. Signed-off-by: Wang Qing Signed-off-by: David S. Miller

drivers: hamradio: 6pack: fix UAF bug caused by mod_timer()

2022-02-18T10:58:17Z

When a 6pack device is detaching, the sixpack_close() will act to cleanup necessary resources. Although del_timer_sync() in sixpack_close() won't return if there is an active timer, one could use mod_timer() in sp_xmit_on_air() to wake up timer again by calling userspace syscall such as ax25_sendmsg(), ax25_connect() and ax25_ioctl(). This unexpected waked handler, sp_xmit_on_air(), realizes nothing about the undergoing cleanup and may still call pty_write() to use driver layer resources that have already been released. One of the possible race conditions is shown below: (USE) | (FREE) ax25_sendmsg() | ax25_queue_xmit() | ... | sp_xmit() | sp_encaps() | sixpack_close() sp_xmit_on_air() | del_timer_sync(&sp->tx_t) mod_timer(&sp->tx_t,...) | ... | unregister_netdev() | ... (wait a while) | tty_release() | tty_release_struct() | release_tty() sp_xmit_on_air() | tty_kref_put(tty_struct) //FREE pty_write(tty_struct) //USE | ... The corresponding fail log is shown below: =============================================================== BUG: KASAN: use-after-free in __run_timers.part.0+0x170/0x470 Write of size 8 at addr ffff88800a652ab8 by task swapper/2/0 ... Call Trace: ... queue_work_on+0x3f/0x50 pty_write+0xcd/0xe0pty_write+0xcd/0xe0 sp_xmit_on_air+0xb2/0x1f0 call_timer_fn+0x28/0x150 __run_timers.part.0+0x3c2/0x470 run_timer_softirq+0x3b/0x80 __do_softirq+0xf1/0x380 ... This patch reorders the del_timer_sync() after the unregister_netdev() to avoid UAF bugs. Because the unregister_netdev() is well synchronized, it flushs out any pending queues, waits the refcount of net_device decreases to zero and removes net_device from kernel. There is not any running routines after executing unregister_netdev(). Therefore, we could not arouse timer from userspace again. Signed-off-by: Duoming Zhou Reviewed-by: Lin Ma Signed-off-by: David S. Miller