linux/net/can/bcm.c

1746 lines
42 KiB

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 17:04:11 +09:00
can: avoid using timeval for uapi The can subsystem communicates with user space using a bcm_msg_head header, which contains two timestamps. This is problematic for multiple reasons: a) The structure layout is currently incompatible between 64-bit user space and 32-bit user space, and cannot work in compat mode (other than x32). b) The timeval structure layout will change in 32-bit user space when we fix the y2038 overflow problem by redefining time_t to 64-bit, making new 32-bit user space incompatible with the current kernel interface. Cars last a long time and often use old kernels, so the actual users of this code are the most likely ones to migrate to y2038 safe user space. This tries to work around part of the problem by changing the publicly visible user interface in the header, but not the binary interface. Fortunately, the values passed around in the structure are relative times and do not actually suffer from the y2038 overflow, so 32-bit is enough here. We replace the use of 'struct timeval' with a newly defined 'struct bcm_timeval' that uses the exact same binary layout as before and that still suffers from problem a) but not problem b). The downside of this approach is that any user space program that currently assigns a timeval structure to these members rather than writing the tv_sec/tv_usec portions individually will suffer a compile-time error when built with an updated kernel header. Fixing this error makes it work fine with old and new headers though. We could address problem a) by using '__u32' or 'int' members rather than 'long', but that would have a more significant downside in also breaking support for all existing 64-bit user binaries that might be using this interface, which is likely not acceptable. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Cc: linux-can@vger.kernel.org Cc: linux-api@vger.kernel.org Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2015-09-30 13:26:42 +02:00
can: avoid using timeval for uapi The can subsystem communicates with user space using a bcm_msg_head header, which contains two timestamps. This is problematic for multiple reasons: a) The structure layout is currently incompatible between 64-bit user space and 32-bit user space, and cannot work in compat mode (other than x32). b) The timeval structure layout will change in 32-bit user space when we fix the y2038 overflow problem by redefining time_t to 64-bit, making new 32-bit user space incompatible with the current kernel interface. Cars last a long time and often use old kernels, so the actual users of this code are the most likely ones to migrate to y2038 safe user space. This tries to work around part of the problem by changing the publicly visible user interface in the header, but not the binary interface. Fortunately, the values passed around in the structure are relative times and do not actually suffer from the y2038 overflow, so 32-bit is enough here. We replace the use of 'struct timeval' with a newly defined 'struct bcm_timeval' that uses the exact same binary layout as before and that still suffers from problem a) but not problem b). The downside of this approach is that any user space program that currently assigns a timeval structure to these members rather than writing the tv_sec/tv_usec portions individually will suffer a compile-time error when built with an updated kernel header. Fixing this error makes it work fine with old and new headers though. We could address problem a) by using '__u32' or 'int' members rather than 'long', but that would have a more significant downside in also breaking support for all existing 64-bit user binaries that might be using this interface, which is likely not acceptable. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Cc: linux-can@vger.kernel.org Cc: linux-api@vger.kernel.org Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2015-09-30 13:26:42 +02:00
net: convert %p usage to %pK The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". The supporting code for kptr_restrict and %pK are currently in the -mm tree. This patch converts users of %p in net/ to %pK. Cases of printing pointers to the syslog are not covered, since this would eliminate useful information for postmortem debugging and the reading of the syslog is already optionally protected by the dmesg_restrict sysctl. Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-23 12:17:35 +00:00
can: avoid using timeval for uapi The can subsystem communicates with user space using a bcm_msg_head header, which contains two timestamps. This is problematic for multiple reasons: a) The structure layout is currently incompatible between 64-bit user space and 32-bit user space, and cannot work in compat mode (other than x32). b) The timeval structure layout will change in 32-bit user space when we fix the y2038 overflow problem by redefining time_t to 64-bit, making new 32-bit user space incompatible with the current kernel interface. Cars last a long time and often use old kernels, so the actual users of this code are the most likely ones to migrate to y2038 safe user space. This tries to work around part of the problem by changing the publicly visible user interface in the header, but not the binary interface. Fortunately, the values passed around in the structure are relative times and do not actually suffer from the y2038 overflow, so 32-bit is enough here. We replace the use of 'struct timeval' with a newly defined 'struct bcm_timeval' that uses the exact same binary layout as before and that still suffers from problem a) but not problem b). The downside of this approach is that any user space program that currently assigns a timeval structure to these members rather than writing the tv_sec/tv_usec portions individually will suffer a compile-time error when built with an updated kernel header. Fixing this error makes it work fine with old and new headers though. We could address problem a) by using '__u32' or 'int' members rather than 'long', but that would have a more significant downside in also breaking support for all existing 64-bit user binaries that might be using this interface, which is likely not acceptable. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Cc: linux-can@vger.kernel.org Cc: linux-api@vger.kernel.org Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2015-09-30 13:26:42 +02:00
can: avoid using timeval for uapi The can subsystem communicates with user space using a bcm_msg_head header, which contains two timestamps. This is problematic for multiple reasons: a) The structure layout is currently incompatible between 64-bit user space and 32-bit user space, and cannot work in compat mode (other than x32). b) The timeval structure layout will change in 32-bit user space when we fix the y2038 overflow problem by redefining time_t to 64-bit, making new 32-bit user space incompatible with the current kernel interface. Cars last a long time and often use old kernels, so the actual users of this code are the most likely ones to migrate to y2038 safe user space. This tries to work around part of the problem by changing the publicly visible user interface in the header, but not the binary interface. Fortunately, the values passed around in the structure are relative times and do not actually suffer from the y2038 overflow, so 32-bit is enough here. We replace the use of 'struct timeval' with a newly defined 'struct bcm_timeval' that uses the exact same binary layout as before and that still suffers from problem a) but not problem b). The downside of this approach is that any user space program that currently assigns a timeval structure to these members rather than writing the tv_sec/tv_usec portions individually will suffer a compile-time error when built with an updated kernel header. Fixing this error makes it work fine with old and new headers though. We could address problem a) by using '__u32' or 'int' members rather than 'long', but that would have a more significant downside in also breaking support for all existing 64-bit user binaries that might be using this interface, which is likely not acceptable. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Cc: linux-can@vger.kernel.org Cc: linux-api@vger.kernel.org Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2015-09-30 13:26:42 +02:00
can: Fix kernel panic at security_sock_rcv_skb Zhang Yanmin reported crashes [1] and provided a patch adding a synchronize_rcu() call in can_rx_unregister() The main problem seems that the sockets themselves are not RCU protected. If CAN uses RCU for delivery, then sockets should be freed only after one RCU grace period. Recent kernels could use sock_set_flag(sk, SOCK_RCU_FREE), but let's ease stable backports with the following fix instead. [1] BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81495e25>] selinux_socket_sock_rcv_skb+0x65/0x2a0 Call Trace: <IRQ> [<ffffffff81485d8c>] security_sock_rcv_skb+0x4c/0x60 [<ffffffff81d55771>] sk_filter+0x41/0x210 [<ffffffff81d12913>] sock_queue_rcv_skb+0x53/0x3a0 [<ffffffff81f0a2b3>] raw_rcv+0x2a3/0x3c0 [<ffffffff81f06eab>] can_rcv_filter+0x12b/0x370 [<ffffffff81f07af9>] can_receive+0xd9/0x120 [<ffffffff81f07beb>] can_rcv+0xab/0x100 [<ffffffff81d362ac>] __netif_receive_skb_core+0xd8c/0x11f0 [<ffffffff81d36734>] __netif_receive_skb+0x24/0xb0 [<ffffffff81d37f67>] process_backlog+0x127/0x280 [<ffffffff81d36f7b>] net_rx_action+0x33b/0x4f0 [<ffffffff810c88d4>] __do_softirq+0x184/0x440 [<ffffffff81f9e86c>] do_softirq_own_stack+0x1c/0x30 <EOI> [<ffffffff810c76fb>] do_softirq.part.18+0x3b/0x40 [<ffffffff810c8bed>] do_softirq+0x1d/0x20 [<ffffffff81d30085>] netif_rx_ni+0xe5/0x110 [<ffffffff8199cc87>] slcan_receive_buf+0x507/0x520 [<ffffffff8167ef7c>] flush_to_ldisc+0x21c/0x230 [<ffffffff810e3baf>] process_one_work+0x24f/0x670 [<ffffffff810e44ed>] worker_thread+0x9d/0x6f0 [<ffffffff810e4450>] ? rescuer_thread+0x480/0x480 [<ffffffff810ebafc>] kthread+0x12c/0x150 [<ffffffff81f9ccef>] ret_from_fork+0x3f/0x70 Reported-by: Zhang Yanmin <yanmin.zhang@intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27 08:11:44 -08:00
can: Fix kernel panic at security_sock_rcv_skb Zhang Yanmin reported crashes [1] and provided a patch adding a synchronize_rcu() call in can_rx_unregister() The main problem seems that the sockets themselves are not RCU protected. If CAN uses RCU for delivery, then sockets should be freed only after one RCU grace period. Recent kernels could use sock_set_flag(sk, SOCK_RCU_FREE), but let's ease stable backports with the following fix instead. [1] BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81495e25>] selinux_socket_sock_rcv_skb+0x65/0x2a0 Call Trace: <IRQ> [<ffffffff81485d8c>] security_sock_rcv_skb+0x4c/0x60 [<ffffffff81d55771>] sk_filter+0x41/0x210 [<ffffffff81d12913>] sock_queue_rcv_skb+0x53/0x3a0 [<ffffffff81f0a2b3>] raw_rcv+0x2a3/0x3c0 [<ffffffff81f06eab>] can_rcv_filter+0x12b/0x370 [<ffffffff81f07af9>] can_receive+0xd9/0x120 [<ffffffff81f07beb>] can_rcv+0xab/0x100 [<ffffffff81d362ac>] __netif_receive_skb_core+0xd8c/0x11f0 [<ffffffff81d36734>] __netif_receive_skb+0x24/0xb0 [<ffffffff81d37f67>] process_backlog+0x127/0x280 [<ffffffff81d36f7b>] net_rx_action+0x33b/0x4f0 [<ffffffff810c88d4>] __do_softirq+0x184/0x440 [<ffffffff81f9e86c>] do_softirq_own_stack+0x1c/0x30 <EOI> [<ffffffff810c76fb>] do_softirq.part.18+0x3b/0x40 [<ffffffff810c8bed>] do_softirq+0x1d/0x20 [<ffffffff81d30085>] netif_rx_ni+0xe5/0x110 [<ffffffff8199cc87>] slcan_receive_buf+0x507/0x520 [<ffffffff8167ef7c>] flush_to_ldisc+0x21c/0x230 [<ffffffff810e3baf>] process_one_work+0x24f/0x670 [<ffffffff810e44ed>] worker_thread+0x9d/0x6f0 [<ffffffff810e4450>] ? rescuer_thread+0x480/0x480 [<ffffffff810ebafc>] kthread+0x12c/0x150 [<ffffffff81f9ccef>] ret_from_fork+0x3f/0x70 Reported-by: Zhang Yanmin <yanmin.zhang@intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27 08:11:44 -08:00
net: Generalize socket rx gap / receive queue overflow cmsg Create a new socket level option to report number of queue overflows Recently I augmented the AF_PACKET protocol to report the number of frames lost on the socket receive queue between any two enqueued frames. This value was exported via a SOL_PACKET level cmsg. AFter I completed that work it was requested that this feature be generalized so that any datagram oriented socket could make use of this option. As such I've created this patch, It creates a new SOL_SOCKET level option called SO_RXQ_OVFL, which when enabled exports a SOL_SOCKET level cmsg that reports the nubmer of times the sk_receive_queue overflowed between any two given frames. It also augments the AF_PACKET protocol to take advantage of this new feature (as it previously did not touch sk->sk_drops, which this patch uses to record the overflow count). Tested successfully by me. Notes: 1) Unlike my previous patch, this patch simply records the sk_drops value, which is not a number of drops between packets, but rather a total number of drops. Deltas must be computed in user space. 2) While this patch currently works with datagram oriented protocols, it will also be accepted by non-datagram oriented protocols. I'm not sure if thats agreeable to everyone, but my argument in favor of doing so is that, for those protocols which aren't applicable to this option, sk_drops will always be zero, and reporting no drops on a receive queue that isn't used for those non-participating protocols seems reasonable to me. This also saves us having to code in a per-protocol opt in mechanism. 3) This applies cleanly to net-next assuming that commit 977750076d98c7ff6cbda51858bb5a5894a9d9ab (my af packet cmsg patch) is reverted Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-12 13:26:31 -07:00