linux-stable.git/net/lapb, branch v4.14.331

net: lapb: Copy the skb before sending a packet

2021-02-10T08:12:08+00:00

[ Upstream commit 88c7a9fd9bdd3e453f04018920964c6f848a591a ]

When sending a packet, we will prepend it with an LAPB header.
This modifies the shared parts of a cloned skb, so we should copy the
skb rather than just clone it, before we prepend the header.

In "Documentation/networking/driver.rst" (the 2nd point), it states
that drivers shouldn't modify the shared parts of a cloned skb when
transmitting.

The "dev_queue_xmit_nit" function in "net/core/dev.c", which is called
when an skb is being sent, clones the skb and sents the clone to
AF_PACKET sockets. Because the LAPB drivers first remove a 1-byte
pseudo-header before handing over the skb to us, if we don't copy the
skb before prepending the LAPB header, the first byte of the packets
received on AF_PACKET sockets can be corrupted.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Xie He 
Acked-by: Martin Schiller 
Link: https://lore.kernel.org/r/20210201055706.415842-1-xie.he.0141@gmail.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

lapb: fixed leak of control-blocks.

2019-06-22T06:16:14+00:00

[ Upstream commit 6be8e297f9bcea666ea85ac7a6cd9d52d6deaf92 ]

lapb_register calls lapb_create_cb, which initializes the control-
block's ref-count to one, and __lapb_insert_cb, which increments it when
adding the new block to the list of blocks.

lapb_unregister calls __lapb_remove_cb, which decrements the ref-count
when removing control-block from the list of blocks, and calls lapb_put
itself to decrement the ref-count before returning.

However, lapb_unregister also calls __lapb_devtostruct to look up the
right control-block for the given net_device, and __lapb_devtostruct
also bumps the ref-count, which means that when lapb_unregister returns
the ref-count is still 1 and the control-block is leaked.

Call lapb_put after __lapb_devtostruct to fix leak.

Reported-by: syzbot+afb980676c836b4a0afa@syzkaller.appspotmail.com
Signed-off-by: Jeremy Sowden 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net, lapb: convert lapb_cb.refcnt from atomic_t to refcount_t

2017-07-04T21:35:16+00:00

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova 
Signed-off-by: Hans Liljestrand 
Signed-off-by: Kees Cook 
Signed-off-by: David Windsor 
Signed-off-by: David S. Miller

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
  sed -i -e "s!$PATT!#include !" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro 
Signed-off-by: Linus Torvalds

net/lapb: tuse %*ph to dump buffers

2016-05-30T05:33:25+00:00

Use %*ph specifier to dump small buffers in hex format instead doing this
byte-by-byte.

Signed-off-by: Andy Shevchenko 
Signed-off-by: David S. Miller

lapb: move EXPORT_SYMBOL after functions.

2014-10-24T19:51:42+00:00

See Documentation/CodingStyle Chapter 6

Signed-off-by: Fabian Frederick 
Signed-off-by: David S. Miller

net/lapb: re-send packets on timeout

2013-09-23T20:52:45+00:00

Actually re-send packets when the T1 timer runs out. This fixes a bug
where packets are waiting on the write queue until disconnection when
no other traffic is outstanding.

Signed-off-by: Josselin Costanzi 
Signed-off-by: Maxime Jayat 
Signed-off-by: David S. Miller

net/lapb: remove depends on CONFIG_EXPERIMENTAL

2013-01-11T19:40:01+00:00

The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: "David S. Miller" 
Signed-off-by: Kees Cook 
Acked-by: David S. Miller

lapb: Neaten debugging

2012-05-17T22:45:20+00:00

Enable dynamic debugging and remove a bunch of #ifdef/#endifs.

Add a lapb_dbg(level, fmt, ...) macro and replace the
printk(KERN_DEBUG uses.
Add pr_fmt and remove embedded prefixes.

Signed-off-by: Joe Perches 
Signed-off-by: David S. Miller

Remove all #inclusions of asm/system.h

2012-03-28T17:30:03+00:00

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*.*\n!!' `grep -Irl '^#\s*include\s*' *`

Signed-off-by: David Howells