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2019-03-25batman-adv: Drop license boilerplateSven Eckelmann1-12/+0
All files got a SPDX-License-Identifier with commit 7db7d9f369a4 ("batman-adv: Add SPDX license identifier above copyright header"). All the required information about the license conditions can be found in LICENSES/. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2019-01-04batman-adv: Update copyright years for 2019Sven Eckelmann1-1/+1
Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-11-12batman-adv: Expand merged fragment buffer for full packetSven Eckelmann1-1/+1
The complete size ("total_size") of the fragmented packet is stored in the fragment header and in the size of the fragment chain. When the fragments are ready for merge, the skbuff's tail of the first fragment is expanded to have enough room after the data pointer for at least total_size. This means that it gets expanded by total_size - first_skb->len. But this is ignoring the fact that after expanding the buffer, the fragment header is pulled by from this buffer. Assuming that the tailroom of the buffer was already 0, the buffer after the data pointer of the skbuff is now only total_size - len(fragment_header) large. When the merge function is then processing the remaining fragments, the code to copy the data over to the merged skbuff will cause an skb_over_panic when it tries to actually put enough data to fill the total_size bytes of the packet. The size of the skb_pull must therefore also be taken into account when the buffer's tailroom is expanded. Fixes: 610bfc6bc99b ("batman-adv: Receive fragmented packets and merge") Reported-by: Martin Weinelt <martin@darmstadt.freifunk.net> Co-authored-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-03-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+2
All of the conflicts were cases of overlapping changes. In net/core/devlink.c, we have to make care that the resouce size_params have become a struct member rather than a pointer to such an object. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-26batman-adv: Update copyright years for 2018Sven Eckelmann1-1/+1
Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-02-25batman-adv: invalidate checksum on fragment reassemblyMatthias Schiffer1-1/+2
A more sophisticated implementation could try to combine fragment checksums when all fragments have CHECKSUM_COMPLETE and are split at even offsets. For now, we just set ip_summed to CHECKSUM_NONE to avoid "hw csum failure" warnings in the kernel log when fragmented frames are received. In consequence, skb_pull_rcsum() can be replaced with skb_pull(). Note that in usual setups, packets don't reach batman-adv with CHECKSUM_COMPLETE (I assume NICs bail out of checksumming when they see batadv's ethtype?), which is why the log messages do not occur on every system using batman-adv. I could reproduce this issue by stacking batman-adv on top of a VXLAN interface. Fixes: 610bfc6bc99b ("batman-adv: Receive fragmented packets and merge") Tested-by: Maximilian Wilhelm <max@sdn.clinic> Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-21batman-adv: Convert packet.h to uapi headerSven Eckelmann1-1/+1
The header file is used by different userspace programs to inject packets or to decode sniffed packets. It should therefore be available to them as userspace header. Also other components in the kernel (like the flow dissector) require access to the packet definitions to be able to decode ETH_P_BATMAN ethernet packets. Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-20Merge tag 'batadv-next-for-davem-20171220' of git://git.open-mesh.org/linux-mergeDavid S. Miller1-11/+12
Simon Wunderlich says: ==================== This feature/cleanup patchset includes the following patches: - bump version strings, by Simon Wunderlich - de-inline hash functions to save memory footprint, by Denys Vlasenko - Add License information to various files, by Sven Eckelmann (3 patches) - Change batman_adv.h from ISC to MIT, by Sven Eckelmann - Improve various includes, by Sven Eckelmann (5 patches) - Lots of kernel-doc work by Sven Eckelmann (8 patches) ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-15batman-adv: Use parentheses in function kernel-docSven Eckelmann1-10/+10
The documentation describing kernel-doc comments for functions ("How to format kernel-doc comments") uses parentheses at the end of the function name. Using this format allows to use a consistent style when adding documentation to a function and when referencing this function in a different kernel-doc section. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-15batman-adv: include gfp.h for GFP_* definesSven Eckelmann1-1/+1
The linux/gfp.h provides the GFP_ATOMIC and GFP_KERNEL define. It should therefore be included instead of linux/fs.h. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-15batman-adv: Add SPDX license identifier above copyright headerSven Eckelmann1-0/+1
The "Linux kernel licensing rules" require that each file has a SPDX license identifier as first line (and sometimes as second line). The FSFE REUSE practices [1] would also require the same tags but have no restrictions on the placement in the source file. Using the "Linux kernel licensing rules" is therefore also fulfilling the FSFE REUSE practices requirements at the same time. [1] https://reuse.software/practices/ Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-12-01batman-adv: Always initialize fragment header prioritySven Eckelmann1-0/+2
The batman-adv unuicast fragment header contains 3 bits for the priority of the packet. These bits will be initialized when the skb->priority contains a value between 256 and 263. But otherwise, the uninitialized bits from the stack will be used. Fixes: c0f25c802b33 ("batman-adv: Include frame priority in fragment header") Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-06-16networking: introduce and use skb_put_data()Johannes Berg1-2/+1
A common pattern with skb_put() is to just want to memcpy() some data into the new space, introduce skb_put_data() for this. An spatch similar to the one for skb_put_zero() converts many of the places using it: @@ identifier p, p2; expression len, skb, data; type t, t2; @@ ( -p = skb_put(skb, len); +p = skb_put_data(skb, data, len); | -p = (t)skb_put(skb, len); +p = skb_put_data(skb, data, len); ) ( p2 = (t2)p; -memcpy(p2, data, len); | -memcpy(p, data, len); ) @@ type t, t2; identifier p, p2; expression skb, data; @@ t *p; ... ( -p = skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); | -p = (t *)skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); ) ( p2 = (t2)p; -memcpy(p2, data, sizeof(*p)); | -memcpy(p, data, sizeof(*p)); ) @@ expression skb, len, data; @@ -memcpy(skb_put(skb, len), data, len); +skb_put_data(skb, data, len); (again, manually post-processed to retain some comments) Reviewed-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16Merge tag 'batadv-net-for-davem-20170316' of git://git.open-mesh.org/linux-mergeDavid S. Miller1-7/+13
Simon Wunderlich says: ==================== Here are two batman-adv bugfixes: - Keep fragments equally sized, avoids some problems with too small fragments, by Sven Eckelmann - Initialize gateway class correctly when BATMAN V is compiled in, by Sven Eckelmann ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-04batman-adv: Keep fragments equally sizedSven Eckelmann1-7/+13
The batman-adv fragmentation packets have the design problem that they cannot be refragmented and cannot handle padding by the underlying link. The latter often leads to problems when networks are incorrectly configured and don't use a common MTU. The sender could for example fragment a 1271 byte frame (plus external ethernet header (14) and batadv unicast header (10)) to fit in a 1280 bytes large MTU of the underlying link (max. 1294 byte frames). This would create a 1294 bytes large frame (fragment 2) and a 55 bytes large frame (fragment 1). The extra 54 bytes are the fragment header (20) added to each fragment and the external ethernet header (14) for the second fragment. Let us assume that the next hop is then not able to transport 1294 bytes to its next hop. The 1294 byte large frame will be dropped but the 55 bytes large fragment will still be forwarded to its destination. Or let us assume that the underlying hardware requires that each frame has a minimum size (e.g. 60 bytes). Then it will pad the 55 bytes frame to 60 bytes. The receiver of the 60 bytes frame will no longer be able to correctly assemble the two frames together because it is not aware that 5 bytes of the 60 bytes frame are padding and don't belong to the reassembled frame. This can partly be avoided by splitting frames more equally. In this example, the 675 and 674 bytes large fragment frames could both potentially reach its destination without being too large or too small. Reported-by: Martin Weinelt <martin@darmstadt.freifunk.net> Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-03-02Merge tag 'batadv-net-for-davem-20170301' of git://git.open-mesh.org/linux-mergeDavid S. Miller1-9/+11
Simon Wunderlich says: ==================== Here are two batman-adv bugfixes: - fix a potential double free when fragment merges fail, by Sven Eckelmann - fix failing tranmission of the 16th (last) fragment if that exists, by Linus Lüssing ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-21batman-adv: Fix transmission of final, 16th fragmentLinus Lüssing1-6/+6
Trying to split and transmit a unicast packet in 16 parts will fail for the final fragment: After having sent the 15th one with a frag_packet.no index of 14, we will increase the the index to 15 - and return with an error code immediately, even though one more fragment is due for transmission and allowed. Fixing this issue by moving the check before incrementing the index. While at it, adding an unlikely(), because the check is actually more of an assertion. Fixes: ee75ed88879a ("batman-adv: Fragment and send skbs larger than mtu") Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-02-21batman-adv: Fix double free during fragment merge errorSven Eckelmann1-3/+5
The function batadv_frag_skb_buffer was supposed not to consume the skbuff on errors. This was followed in the helper function batadv_frag_insert_packet when the skb would potentially be inserted in the fragment queue. But it could happen that the next helper function batadv_frag_merge_packets would try to merge the fragments and fail. This results in a kfree_skb of all the enqueued fragments (including the just inserted one). batadv_recv_frag_packet would detect the error in batadv_frag_skb_buffer and try to free the skb again. The behavior of batadv_frag_skb_buffer (and its helper batadv_frag_insert_packet) must therefore be changed to always consume the skbuff to have a common behavior and avoid the double kfree_skb. Fixes: 610bfc6bc99b ("batman-adv: Receive fragmented packets and merge") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-01-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-5/+5
Two trivial overlapping changes conflicts in MPLS and mlx5. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-26batman-adv: update copyright years for 2017Sven Eckelmann1-1/+1
Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2017-01-04batman-adv: Decrease hardif refcnt on fragmentation send errorSven Eckelmann1-5/+5
An error before the hardif is found has to free the skb. But every error after that has to free the skb + put the hard interface. Fixes: 8def0be82dd1 ("batman-adv: Consume skb in batadv_frag_send_packet") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-10-30batman-adv: Consume skb in batadv_frag_send_packetSven Eckelmann1-21/+29
Sending functions in Linux consume the supplied skbuff. Doing the same in batadv_frag_send_packet avoids the hack of returning -1 (-EPERM) to signal the caller that he is responsible for cleaning up the skb. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-10-30batman-adv: use consume_skb for non-dropped packetsSven Eckelmann1-6/+14
kfree_skb assumes that an skb is dropped after an failure and notes that. consume_skb should be used in non-failure situations. Such information is important for dropmonitor netlink which tells how many packets were dropped and where this drop happened. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-10-19batman-adv: Use proper name for fragments list headSven Eckelmann1-7/+7
The batman-adv codebase is using "list" for the list node (prev/next) and <list content descriptor>+"_list" for the head of a list. Not using this naming scheme can up in confusions because list_head is used for both the head of the list and the list node (prev/next) in each item of the list. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-10-19batman-adv: Remove needless init of variables on stackSven Eckelmann1-2/+2
Some variables are overwritten immediatelly in a functions. These don't have to be initialized to a specific value on the stack because the value will be overwritten before they will be used anywhere. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-07-04batman-adv: return netdev status in the TX pathAntonio Quartulli1-16/+25
Return the proper netdev TX status along the TX path so that the tp_meter can understand when the queue is full and should stop sending packets. Signed-off-by: Antonio Quartulli <antonio.quartulli@open-mesh.com> Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-06-30batman-adv: Include frame priority in fragment headerAndrew Lunn1-0/+9
Unfragmented frames which traverse a node have their skb->priority set by looking at the IP ToS byte, or the 802.1p header. However for fragments this is not possible, only one of the fragments will contain the headers. Instead, place the priority into the fragment header and on receiving a fragment, use this information to set the skb->priority for when the fragment is forwarded. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-06-30batman-adv: Set skb priority in fragmentsAndrew Lunn1-2/+1
BATMAN will set the skb->priority based on the IP precedence or 802.1q tag. However, if it needs to fragment the frame, it currently leaves the fragment skb with the default priority and actually overwrites the priority in the unfragmented frame. Fix this. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2016-05-04batman-adv: Fix checkpatch warning about 'unsigned' typeSven Eckelmann1-6/+6
checkpatch.pl warns about the use of 'unsigned' as a short form for 'unsigned int'. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-02-29batman-adv: keep track of when unicast packets are sentAntonio Quartulli1-5/+3
To enable ELP to send probing packets over wireless links only if needed, batman-adv must keep track of the last time it sent a unicast packet towards every neighbour. For this purpose a 2 main changes are introduced: 1) a new member of the elp_neigh_node structure stores the last time a unicast packet was sent towards this neighbour; 2) a wrapper function for sending unicast packets is implemented. This function will simply update the member describe din point 1) and then forward the packet to the real sending routine. Point 2) implies that any code-path leading to a unicast sending now has to use the new wrapper. Signed-off-by: Antonio Quartulli <antonio@open-mesh.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
2016-02-23batman-adv: Rename batadv_neigh_node *_free_ref function to *_putSven Eckelmann1-1/+1
The batman-adv source code is the only place in the kernel which uses the *_free_ref naming scheme for the *_put functions. Changing it to *_put makes it more consistent and makes it easier to understand the connection to the *_get functions. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-02-23batman-adv: Rename batadv_hardif *_free_ref function to *_putSven Eckelmann1-1/+1
The batman-adv source code is the only place in the kernel which uses the *_free_ref naming scheme for the *_put functions. Changing it to *_put makes it more consistent and makes it easier to understand the connection to the *_get functions. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-02-23batman-adv: Rename batadv_orig_node *_free_ref function to *_putSven Eckelmann1-1/+1
The batman-adv source code is the only place in the kernel which uses the *_free_ref naming scheme for the *_put functions. Changing it to *_put makes it more consistent and makes it easier to understand the connection to the *_get functions. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-02-02batman-adv: update copyright years for 2016Sven Eckelmann1-1/+1
Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-02-02batman-adv: Fix kerneldoc parsing of return descriptionSven Eckelmann1-7/+10
Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc>
2016-02-02batman-adv: Remove kerneldoc for missing parametersSven Eckelmann1-1/+0
Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc>
2015-12-16batman-adv: Use chain pointer when purging fragmentsSven Eckelmann1-4/+4
The chain pointer was already created in batadv_frag_purge_orig to make the checks more readable. Just use the chain pointer everywhere instead of having the same dereference + array access in the most lines of this function. Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Martin Hundebøll <martin@hundeboll.net> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
2015-08-25batman-adv: Add lockdep_asserts for documented external locksSven Eckelmann1-0/+3
Some functions already have documentation about locks they require inside their kerneldoc header. These can be directly tested during runtime using the lockdep asserts. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
2015-08-25batman-adv: Replace C99 int types with kernel typeSven Eckelmann1-5/+5
(s|u)(8|16|32|64) are the preferred types in the kernel. The use of the standard C99 types u?int(8|16|32|64)_t are objected by some people and even checkpatch now warns about using them. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
2015-06-07batman-adv: Add required includes to all filesSven Eckelmann1-3/+19
The header files could not be build indepdent from each other. This is happened because headers didn't include the files for things they've used. This was problematic because the success of a build depended on the knowledge about the right order of local includes. Also source files were not including everything they've used explicitly. Instead they required that transitive includes are always stable. This is problematic because some transitive includes are not obvious, depend on config settings and may not be stable in the future. The order for include blocks are: * primary headers (main.h and the *.h file of a *.c file) * global linux headers * required local headers * extra forward declarations for pointers in function/struct declarations The only exceptions are linux/bitops.h and linux/if_ether.h in packet.h. This header file is shared with userspace applications like batctl and must therefore build together with userspace applications. The header linux/bitops.h is not part of the uapi headers and linux/if_ether.h conflicts with the musl implementation of netinet/if_ether.h. The maintainers rejected the use of __KERNEL__ preprocessor checks and thus these two headers are only in main.h. All files using packet.h first have to include main.h to work correctly. Reported-by: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
2015-05-29batman-adv: Use only queued fragments when mergingSven Eckelmann1-8/+5
The fragment queueing code now validates the total_size of each fragment, checks when enough fragments are queued to allow to merge them into a single packet and if the fragments have the correct size. Therefore, it is not required to have any other parameter for the merging function than a list of queued fragments. This change should avoid problems like in the past when the different skb from the list and the function parameter were mixed incorrectly. Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Martin Hundebøll <martin@hundeboll.net> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
2015-05-29batman-adv: Check total_size when queueing fragmentsSven Eckelmann1-2/+5
The fragmentation code was replaced in 610bfc6bc99bc83680d190ebc69359a05fc7f605 ("batman-adv: Receive fragmented packets and merge") by an implementation which handles the queueing+merging of fragments based on their size and the total_size of the non-fragmented packet. This total_size is announced by each fragment. The new implementation doesn't check if the the total_size information of the packets inside one chain is consistent. This is consistency check is recommended to allow using any of the packets in the queue to decide whether all fragments of a packet are received or not. Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Martin Hundebøll <martin@hundeboll.net> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
2015-05-29batman-adv: update copyright years for 2015Sven Eckelmann1-1/+1
Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
2015-01-07batman-adv: checkpatch - Please don't use multiple blank linesAntonio Quartulli1-1/+0
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
2014-12-23batman-adv: Unify fragment size calculationSven Eckelmann1-1/+1
The fragmentation code was replaced in 610bfc6bc99bc83680d190ebc69359a05fc7f605 ("batman-adv: Receive fragmented packets and merge") by an implementation which can handle up to 16 fragments of a packet. The packet is prepared for the split in fragments by the function batadv_frag_send_packet and the actual split is done by batadv_frag_create. Both functions calculate the size of a fragment themself. But their calculation differs because batadv_frag_send_packet also subtracts ETH_HLEN. Therefore, the check in batadv_frag_send_packet "can a full fragment can be created?" may return true even when batadv_frag_create cannot create a full fragment. The function batadv_frag_create doesn't check the size of the skb before splitting it and therefore might try to create a larger fragment than the remaining buffer. This creates an integer underflow and an invalid len is given to skb_split. Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-23batman-adv: Calculate extra tail size based on queued fragmentsSven Eckelmann1-1/+1
The fragmentation code was replaced in 610bfc6bc99bc83680d190ebc69359a05fc7f605 ("batman-adv: Receive fragmented packets and merge"). The new code provided a mostly unused parameter skb for the merging function. It is used inside the function to calculate the additionally needed skb tailroom. But instead of increasing its own tailroom, it is only increasing the tailroom of the first queued skb. This is not correct in some situations because the first queued entry can be a different one than the parameter. An observed problem was: 1. packet with size 104, total_size 1464, fragno 1 was received - packet is queued 2. packet with size 1400, total_size 1464, fragno 0 was received - packet is queued at the end of the list 3. enough data was received and can be given to the merge function (1464 == (1400 - 20) + (104 - 20)) - merge functions gets 1400 byte large packet as skb argument 4. merge function gets first entry in queue (104 byte) - stored as skb_out 5. merge function calculates the required extra tail as total_size - skb->len - pskb_expand_head tail of skb_out with 64 bytes 6. merge function tries to squeeze the extra 1380 bytes from the second queued skb (1400 byte aka skb parameter) in the 64 extra tail bytes of skb_out Instead calculate the extra required tail bytes for skb_out also using skb_out instead of using the parameter skb. The skb parameter is only used to get the total_size from the last received packet. This is also the total_size used to decide that all fragments were received. Reported-by: Philipp Psurek <philipp.psurek@gmail.com> Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Martin Hundebøll <martin@hundeboll.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-16batman-adv: Fix parameter order of hlist_add_behindSven Eckelmann1-1/+1
1d023284c31a4e40a94d5bbcb7dbb7a35ee0bcbc ("list: fix order of arguments for hlist_add_after(_rcu)") was incorrectly rebased on top of d9124268d84a836f14a6ead54ff9d8eee4c43be5 ("batman-adv: Fix out-of-order fragmentation support"). The parameter order change of the rebased patch was not re-applied as expected. This causes a memory leak and can cause crashes when out-of-order packets are received. hlist_add_behind will try to access the uninitalized list pointers of frag_entry_new to find the previous/next entry and may modify/read random memory locations. Signed-off-by: Sven Eckelmann <sven@narfation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-06list: fix order of arguments for hlist_add_after(_rcu)Ken Helias1-1/+1
All other add functions for lists have the new item as first argument and the position where it is added as second argument. This was changed for no good reason in this function and makes using it unnecessary confusing. The name was changed to hlist_add_behind() to cause unconverted code to generate a compile error instead of using the wrong parameter order. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Ken Helias <kenhelias@firemail.de> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> [intel driver bits] Cc: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-05batman-adv: Fix out-of-order fragmentation supportSven Eckelmann1-3/+7
batadv_frag_insert_packet was unable to handle out-of-order packets because it dropped them directly. This is caused by the way the fragmentation lists is checked for the correct place to insert a fragmentation entry. The fragmentation code keeps the fragments in lists. The fragmentation entries are kept in descending order of sequence number. The list is traversed and each entry is compared with the new fragment. If the current entry has a smaller sequence number than the new fragment then the new one has to be inserted before the current entry. This ensures that the list is still in descending order. An out-of-order packet with a smaller sequence number than all entries in the list still has to be added to the end of the list. The used hlist has no information about the last entry in the list inside hlist_head and thus the last entry has to be calculated differently. Currently the code assumes that the iterator variable of hlist_for_each_entry can be used for this purpose after the hlist_for_each_entry finished. This is obviously wrong because the iterator variable is always NULL when the list was completely traversed. Instead the information about the last entry has to be stored in a different variable. This problem was introduced in 610bfc6bc99bc83680d190ebc69359a05fc7f605 ("batman-adv: Receive fragmented packets and merge"). Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
2014-05-15batman-adv: fix reference counting imbalance while sending fragmentAntonio Quartulli1-3/+8
In the new fragmentation code the batadv_frag_send_packet() function obtains a reference to the primary_if, but it does not release it upon return. This reference imbalance prevents the primary_if (and then the related netdevice) to be properly released on shut down. Fix this by releasing the primary_if in batadv_frag_send_packet(). Introduced by ee75ed88879af88558818a5c6609d85f60ff0df4 ("batman-adv: Fragment and send skbs larger than mtu") Cc: Martin Hundebøll <martin@hundeboll.net> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Acked-by: Martin Hundebøll <martin@hundeboll.net>