- 05 Dec, 2015 6 commits
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Jason Wang authored
commit 48900cb6 upstream. virtio declares support for NETIF_F_FRAGLIST, but assumes that there are at most MAX_SKB_FRAGS + 2 fragments which isn't always true with a fraglist. A longer fraglist in the skb will make the call to skb_to_sgvec overflow the sg array, leading to memory corruption. Drop NETIF_F_FRAGLIST so we only get what we can handle. Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by:
Jason Wang <jasowang@redhat.com> Acked-by:
Michael S. Tsirkin <mst@redhat.com> Signed-off-by:
David S. Miller <davem@davemloft.net> [bwh: Backported to 2.6.32: there's only a single features field] Signed-off-by:
Ben Hutchings <ben@decadent.org.uk> Signed-off-by:
Willy Tarreau <w@1wt.eu>
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Marcelo Leitner authored
commit 77751427 upstream. Currently we don't check if the new MTU is valid or not and this allows one to configure a smaller than minimum allowed by RFCs or even bigger than interface own MTU, which is a problem as it may lead to packet drops. If you have a daemon like NetworkManager running, this may be exploited by remote attackers by forging RA packets with an invalid MTU, possibly leading to a DoS. (NetworkManager currently only validates for values too small, but not for too big ones.) The fix is just to make sure the new value is valid. That is, between IPV6_MIN_MTU and interface's MTU. Note that similar check is already performed at ndisc_router_discovery(), for when kernel itself parses the RA. Signed-off-by:
Marcelo Ricardo Leitner <mleitner@redhat.com> Signed-off-by:
Sabrina Dubroca <sd@queasysnail.net> Signed-off-by:
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Benjamin Randazzo authored
commit b6878d9e upstream. In drivers/md/md.c get_bitmap_file() uses kmalloc() for creating a mdu_bitmap_file_t called "file". 5769 file = kmalloc(sizeof(*file), GFP_NOIO); 5770 if (!file) 5771 return -ENOMEM; This structure is copied to user space at the end of the function. 5786 if (err == 0 && 5787 copy_to_user(arg, file, sizeof(*file))) 5788 err = -EFAULT But if bitmap is disabled only the first byte of "file" is initialized with zero, so it's possible to read some bytes (up to 4095) of kernel space memory from user space. This is an information leak. 5775 /* bitmap disabled, zero the first byte and copy out */ 5776 if (!mddev->bitmap_info.file) 5777 file->pathname[0] = '\0'; Signed-off-by:
Benjamin Randazzo <benjamin@randazzo.fr> Signed-off-by:
NeilBrown <neilb@suse.com> [bwh: Backported to 2.6.32: patch both possible allocation calls] Signed-off-by:
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Olga Kornievskaia authored
commit a41cbe86 upstream. A test case is as the description says: open(foobar, O_WRONLY); sleep() --> reboot the server close(foobar) The bug is because in nfs4state.c in nfs4_reclaim_open_state() a few line before going to restart, there is clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &state->flags). NFS4CLNT_RECLAIM_NOGRACE is a flag for the client states not open owner states. Value of NFS4CLNT_RECLAIM_NOGRACE is 4 which is the value of NFS_O_WRONLY_STATE in nfs4_state->flags. So clearing it wipes out state and when we go to close it, “call_close” doesn’t get set as state flag is not set and CLOSE doesn’t go on the wire. Signed-off-by:
Olga Kornievskaia <aglo@umich.edu> Signed-off-by:
Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by:
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Eric W. Biederman authored
commit 397d425d upstream. In rare cases a directory can be renamed out from under a bind mount. In those cases without special handling it becomes possible to walk up the directory tree to the root dentry of the filesystem and down from the root dentry to every other file or directory on the filesystem. Like division by zero .. from an unconnected path can not be given a useful semantic as there is no predicting at which path component the code will realize it is unconnected. We certainly can not match the current behavior as the current behavior is a security hole. Therefore when encounting .. when following an unconnected path return -ENOENT. - Add a function path_connected to verify path->dentry is reachable from path->mnt.mnt_root. AKA to validate that rename did not do something nasty to the bind mount. To avoid races path_connected must be called after following a path component to it's next path component. Signed-off-by:
"Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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Eric W. Biederman authored
commit cde93be4 upstream. A rename can result in a dentry that by walking up d_parent will never reach it's mnt_root. For lack of a better term I call this an escaped path. prepend_path is called by four different functions __d_path, d_absolute_path, d_path, and getcwd. __d_path only wants to see paths are connected to the root it passes in. So __d_path needs prepend_path to return an error. d_absolute_path similarly wants to see paths that are connected to some root. Escaped paths are not connected to any mnt_root so d_absolute_path needs prepend_path to return an error greater than 1. So escaped paths will be treated like paths on lazily unmounted mounts. getcwd needs to prepend "(unreachable)" so getcwd also needs prepend_path to return an error. d_path is the interesting hold out. d_path just wants to print something, and does not care about the weird cases. Which raises the question what should be printed? Given that <escaped_path>/<anything> should result in -ENOENT I believe it is desirable for escaped paths to be printed as empty paths. As there are not really any meaninful path components when considered from the perspective of a mount tree. So tweak prepend_path to return an empty path with an new error code of 3 when it encounters an escaped path. Signed-off-by:
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- 18 Sep, 2015 34 commits
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Willy Tarreau authored
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David S. Miller authored
commit 6ac3f664 upstream. Like ipv4, just return xfrm6_rcv_spi()'s return value directly. Signed-off-by:
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Dr. David Alan Gilbert authored
commit d07a74a5 upstream. Hi, On the latest tree my compiler has started giving the warning: drivers/dma/dmatest.c:575:28: warning: the omitted middle operand in ?: will always be ?true?, suggest explicit middle operand [-Wparentheses] The following patch fixes the missing middle clause with the same fix that Nicolas Ferre used in the similar clauses. (There seems to have been a race between him fixing that and the extra clause going in a little later). I don't actually know the dmatest code/structures, nor do I own any hardware to test it on (assuming it needs a DMA engine); but this patch builds, the existing code is almost certainly wrong and the fix is the same as the corresponding lines above it. (WTH is x=y?:z legal C anyway?) Signed-off-by:
Dr. David Alan Gilbert <linux@treblig.org> Reported-by:
Dan Carpenter <dan.carpenter@oracle.com> Reported-by:
Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by:
Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by:
Dan Williams <dan.j.williams@intel.com> Signed-off-by:
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Wang Weidong authored
commit 965cdea8 upstream. Check the return value of request_module during dccp_probe initialisation, bail out if that call fails. Signed-off-by:
Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by:
Wang Weidong <wangweidong1@huawei.com> Signed-off-by:
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David S. Miller authored
commit d984e619 upstream. Commit 1386be55 ("dccp: fix auto-loading of dccp(_probe)") fixed a bug but created a new compiler warning: net/dccp/probe.c: In function ‘dccpprobe_init’: net/dccp/probe.c:166:2: warning: the omitted middle operand in ?: will always be ‘true’, suggest explicit middle operand [-Wparentheses] try_then_request_module() is built for situations where the "existence" test is some lookup function that returns a non-NULL object on success, and with a reference count of some kind held. Here we're looking for a success return of zero from the jprobe registry. Instead of fighting the way try_then_request_module() works, simply open code what we want to happen in a local helper function. Signed-off-by:
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Gerrit Renker authored
commit 1386be55 upstream. This fixes commit (38ff3e6b) ("dccp_probe: Fix module load dependencies between dccp and dccp_probe", from 15 Jan). It fixes the construction of the first argument of try_then_request_module(), where only valid return codes from the first argument should be returned. What we do now is assign the result of register_jprobe() to ret, without the side effect of the comparison. Acked-by:
Neil Horman <nhorman@tuxdriver.com> Signed-off-by:
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Andy Lutomirski authored
commit aa1acff3 upstream. The update_va_mapping hypercall can fail if the VA isn't present in the guest's page tables. Under certain loads, this can result in an OOPS when the target address is in unpopulated vmap space. While we're at it, add comments to help explain what's going on. This isn't a great long-term fix. This code should probably be changed to use something like set_memory_ro. Signed-off-by:
Andy Lutomirski <luto@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <dvrabel@cantab.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: security@kernel.org <security@kernel.org> Cc: xen-devel <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/0b0e55b995cda11e7829f140b833ef932fcabe3a.1438291540.git.luto@kernel.orgSigned-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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Mikulas Patocka authored
commit d531be2c upstream. I have a ST4000DM000 disk. If Linux is booted while the disk is spun down, the command that sets transfer mode causes the disk to spin up. The spin-up takes longer than the default 5s timeout, so the command fails and timeout is reported. Fix this by increasing the timeout to 15s, which is enough for the disk to spin up. Signed-off-by:
Mikulas Patocka <mpatocka@redhat.com> Signed-off-by:
Tejun Heo <tj@kernel.org> Signed-off-by:
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Heiko Carstens authored
commit e47994dd upstream. The sfpc inline assembly within execve_tail() may incorrectly set bits 28-31 of the sfpc instruction to a value which is not zero. These bits however are currently unused and therefore should be zero so we won't get surprised if these bits will be used in the future. Therefore remove the second operand from the inline assembly. Signed-off-by:
Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by:
Martin Schwidefsky <schwidefsky@de.ibm.com> [bwh: Backported to 3.2: adjust context] Signed-off-by:
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Kirill A. Shutemov authored
commit 6b7339f4 upstream. Reading page fault handler code I've noticed that under right circumstances kernel would map anonymous pages into file mappings: if the VMA doesn't have vm_ops->fault() and the VMA wasn't fully populated on ->mmap(), kernel would handle page fault to not populated pte with do_anonymous_page(). Let's change page fault handler to use do_anonymous_page() only on anonymous VMA (->vm_ops == NULL) and make sure that the VMA is not shared. For file mappings without vm_ops->fault() or shred VMA without vm_ops, page fault on pte_none() entry would lead to SIGBUS. Signed-off-by:
Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by:
Oleg Nesterov <oleg@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backported to 3.2: adjust context] Signed-off-by:
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Miklos Szeredi authored
commit 0ad0b325 upstream. fc->release is called from fuse_conn_put() which was used in the error cleanup before fc->release was initialized. [Jeremiah Mahler <jmmahler@gmail.com>: assign fc->release after calling fuse_conn_init(fc) instead of before.] Signed-off-by:
Miklos Szeredi <mszeredi@suse.cz> Fixes: a325f9b9 ("fuse: update fuse_conn_init() and separate out fuse_conn_kill()") Signed-off-by:
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Steven Rostedt (Red Hat) authored
commit 6b88f44e upstream. While debugging a WARN_ON() for filtering, I found that it is possible for the filter string to be referenced after its end. With the filter: # echo '>' > /sys/kernel/debug/events/ext4/ext4_truncate_exit/filter The filter_parse() function can call infix_get_op() which calls infix_advance() that updates the infix filter pointers for the cnt and tail without checking if the filter is already at the end, which will put the cnt to zero and the tail beyond the end. The loop then calls infix_next() that has ps->infix.cnt--; return ps->infix.string[ps->infix.tail++]; The cnt will now be below zero, and the tail that is returned is already passed the end of the filter string. So far the allocation of the filter string usually has some buffer that is zeroed out, but if the filter string is of the exact size of the allocated buffer there's no guarantee that the charater after the nul terminating character will be zero. Luckily, only root can write to the filter. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
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Steven Rostedt (Red Hat) authored
commit b4875bbe upstream. When testing the fix for the trace filter, I could not come up with a scenario where the operand count goes below zero, so I added a WARN_ON_ONCE(cnt < 0) to the logic. But there is legitimate case that it can happen (although the filter would be wrong). # echo '>' > /sys/kernel/debug/events/ext4/ext4_truncate_exit/filter That is, a single operation without any operands will hit the path where the WARN_ON_ONCE() can trigger. Although this is harmless, and the filter is reported as a error. But instead of spitting out a warning to the kernel dmesg, just fail nicely and report it via the proper channels. Link: http://lkml.kernel.org/r/558C6082.90608@oracle.comReported-by:
Vince Weaver <vincent.weaver@maine.edu> Reported-by:
Sasha Levin <sasha.levin@oracle.com> Signed-off-by:
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Catalin Marinas authored
commit c5f3b1a5 upstream. The kmemleak scanning thread can run for minutes. Callbacks like kmemleak_free() are allowed during this time, the race being taken care of by the object->lock spinlock. Such lock also prevents a memory block from being freed or unmapped while it is being scanned by blocking the kmemleak_free() -> ... -> __delete_object() function until the lock is released in scan_object(). When a kmemleak error occurs (e.g. it fails to allocate its metadata), kmemleak_enabled is set and __delete_object() is no longer called on freed objects. If kmemleak_scan is running at the same time, kmemleak_free() no longer waits for the object scanning to complete, allowing the corresponding memory block to be freed or unmapped (in the case of vfree()). This leads to kmemleak_scan potentially triggering a page fault. This patch separates the kmemleak_free() enabling/disabling from the overall kmemleak_enabled nob so that we can defer the disabling of the object freeing tracking until the scanning thread completed. The kmemleak_free_part() is deliberately ignored by this patch since this is only called during boot before the scanning thread started. Signed-off-by:
Catalin Marinas <catalin.marinas@arm.com> Reported-by:
Vignesh Radhakrishnan <vigneshr@codeaurora.org> Tested-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Ralf Baechle authored
commit d496f784 upstream. A ROSE socket doesn't necessarily always have a neighbour pointer so check if the neighbour pointer is valid before dereferencing it. Signed-off-by:
Ralf Baechle <ralf@linux-mips.org> Tested-by:
Bernard Pidoux <f6bvp@free.fr> Signed-off-by:
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Theodore Ts'o authored
commit 89d96a6f upstream. Normally all of the buffers will have been forced out to disk before we call invalidate_bdev(), but there will be some cases, where a file system operation was aborted due to an ext4_error(), where there may still be some dirty buffers in the buffer cache for the device. So try to force them out to memory before calling invalidate_bdev(). This fixes a warning triggered by generic/081: WARNING: CPU: 1 PID: 3473 at /usr/projects/linux/ext4/fs/block_dev.c:56 __blkdev_put+0xb5/0x16f() Signed-off-by:
Theodore Ts'o <tytso@mit.edu> Signed-off-by:
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Jeff Layton authored
commit 764ad8ba upstream. The current buffer is much too small if you have a relatively long hostname. Bring it up to the size of the one that SETCLIENTID has. Reported-by:
Michael Skralivetsky <michael.skralivetsky@primarydata.com> Signed-off-by:
Jeff Layton <jeff.layton@primarydata.com> Signed-off-by:
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Ryan Underwood authored
commit 2fb22a80 upstream. Disable write buffering on the Toshiba ToPIC95 if it is enabled by somebody (it is not supposed to be a power-on default according to the datasheet). On the ToPIC95, practically no 32-bit Cardbus card will work under heavy load without locking up the whole system if this is left enabled. I tried about a dozen. It does not affect 16-bit cards. This is similar to the O2 bugs in early controller revisions it seems. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=55961Signed-off-by:
Ryan C. Underwood <nemesis@icequake.net> Signed-off-by:
Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by:
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Theodore Ts'o authored
commit bdf96838 upstream. The commit cf108bca: "ext4: Invert the locking order of page_lock and transaction start" caused __ext4_journalled_writepage() to drop the page lock before the page was written back, as part of changing the locking order to jbd2_journal_start -> page_lock. However, this introduced a potential race if there was a truncate racing with the data=journalled writeback mode. Fix this by grabbing the page lock after starting the journal handle, and then checking to see if page had gotten truncated out from under us. This fixes a number of different warnings or BUG_ON's when running xfstests generic/086 in data=journalled mode, including: jbd2_journal_dirty_metadata: vdc-8: bad jh for block 115643: transaction (ee3fe7 c0, 164), jh->b_transaction ( (null), 0), jh->b_next_transaction ( (null), 0), jlist 0 - and - kernel BUG at /usr/projects/linux/ext4/fs/jbd2/transaction.c:2200! ... Call Trace: [<c02b2ded>] ? __ext4_journalled_invalidatepage+0x117/0x117 [<c02b2de5>] __ext4_journalled_invalidatepage+0x10f/0x117 [<c02b2ded>] ? __ext4_journalled_invalidatepage+0x117/0x117 [<c027d883>] ? lock_buffer+0x36/0x36 [<c02b2dfa>] ext4_journalled_invalidatepage+0xd/0x22 [<c0229139>] do_invalidatepage+0x22/0x26 [<c0229198>] truncate_inode_page+0x5b/0x85 [<c022934b>] truncate_inode_pages_range+0x156/0x38c [<c0229592>] truncate_inode_pages+0x11/0x15 [<c022962d>] truncate_pagecache+0x55/0x71 [<c02b913b>] ext4_setattr+0x4a9/0x560 [<c01ca542>] ? current_kernel_time+0x10/0x44 [<c026c4d8>] notify_change+0x1c7/0x2be [<c0256a00>] do_truncate+0x65/0x85 [<c0226f31>] ? file_ra_state_init+0x12/0x29 - and - WARNING: CPU: 1 PID: 1331 at /usr/projects/linux/ext4/fs/jbd2/transaction.c:1396 irty_metadata+0x14a/0x1ae() ... Call Trace: [<c01b879f>] ? console_unlock+0x3a1/0x3ce [<c082cbb4>] dump_stack+0x48/0x60 [<c0178b65>] warn_slowpath_common+0x89/0xa0 [<c02ef2cf>] ? jbd2_journal_dirty_metadata+0x14a/0x1ae [<c0178bef>] warn_slowpath_null+0x14/0x18 [<c02ef2cf>] jbd2_journal_dirty_metadata+0x14a/0x1ae [<c02d8615>] __ext4_handle_dirty_metadata+0xd4/0x19d [<c02b2f44>] write_end_fn+0x40/0x53 [<c02b4a16>] ext4_walk_page_buffers+0x4e/0x6a [<c02b59e7>] ext4_writepage+0x354/0x3b8 [<c02b2f04>] ? mpage_release_unused_pages+0xd4/0xd4 [<c02b1b21>] ? wait_on_buffer+0x2c/0x2c [<c02b5a4b>] ? ext4_writepage+0x3b8/0x3b8 [<c02b5a5b>] __writepage+0x10/0x2e [<c0225956>] write_cache_pages+0x22d/0x32c [<c02b5a4b>] ? ext4_writepage+0x3b8/0x3b8 [<c02b6ee8>] ext4_writepages+0x102/0x607 [<c019adfe>] ? sched_clock_local+0x10/0x10e [<c01a8a7c>] ? __lock_is_held+0x2e/0x44 [<c01a8ad5>] ? lock_is_held+0x43/0x51 [<c0226dff>] do_writepages+0x1c/0x29 [<c0276bed>] __writeback_single_inode+0xc3/0x545 [<c0277c07>] writeback_sb_inodes+0x21f/0x36d ... Signed-off-by:
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Lior Amsalem authored
commit 9136291f upstream. This patch fixes a bug in the XOR driver where the cleanup function can be called and free descriptors that never been processed by the engine (which result in data errors). The cleanup function will free descriptors based on the ownership bit in the descriptors. Fixes: ff7b0479 ("dmaengine: DMA engine driver for Marvell XOR engine") Signed-off-by:
Lior Amsalem <alior@marvell.com> Signed-off-by:
Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by:
Ofer Heifetz <oferh@marvell.com> Signed-off-by:
Vinod Koul <vinod.koul@intel.com> [bwh: Backported to 3.2: adjust context] Signed-off-by:
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Trond Myklebust authored
commit 88de6af2 upstream. req->rq_private_buf isn't initialised when xprt_setup_backchannel calls xprt_free_allocation. Fixes: fb7a0b9a ("nfs41: New backchannel helper routines") Signed-off-by:
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Olga Kornievskaia authored
commit e8d975e7 upstream. Problem: When an operation like WRITE receives a BAD_STATEID, even though recovery code clears the RECLAIM_NOGRACE recovery flag before recovering the open state, because of clearing delegation state for the associated inode, nfs_inode_find_state_and_recover() gets called and it makes the same state with RECLAIM_NOGRACE flag again. As a results, when we restart looking over the open states, we end up in the infinite loop instead of breaking out in the next test of state flags. Solution: unset the RECLAIM_NOGRACE set because of calling of nfs_inode_find_state_and_recover() after returning from calling recover_open() function. Signed-off-by:
Olga Kornievskaia <kolga@netapp.com> Signed-off-by:
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Malcolm Priestley authored
commit b5eeed8c upstream. There is a small chance that pRD->pRDInfo->skb could go NULL while the interrupt is processing. Put NULL check on loop to break out. Signed-off-by:
Malcolm Priestley <tvboxspy@gmail.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: adjust context, indentation] Signed-off-by:
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Jesper Dangaard Brouer authored
commit d079abd1 upstream. Too many spaces were introduced in commit 63adc6fb ("pktgen: cleanup checkpatch warnings"), thus misaligning "src_min:" to other columns. Fixes: 63adc6fb ("pktgen: cleanup checkpatch warnings") Signed-off-by:
Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by:
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Mauro Carvalho Chehab authored
commit 1fa2337a upstream. The maximum size for a DiSEqC command is 6, according to the userspace API. However, the code allows to write up much more values: drivers/media/dvb-frontends/cx24116.c:983 cx24116_send_diseqc_msg() error: buffer overflow 'd->msg' 6 <= 23 Signed-off-by:
Mauro Carvalho Chehab <mchehab@osg.samsung.com> [bwh: Backported to 3.2: adjust filename] Signed-off-by:
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Mauro Carvalho Chehab authored
commit 12f4543f upstream. The maximum size for a DiSEqC command is 6, according to the userspace API. However, the code allows to write up to 7 values: drivers/media/dvb-frontends/s5h1420.c:193 s5h1420_send_master_cmd() error: buffer overflow 'cmd->msg' 6 <= 7 Signed-off-by:
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Peter Zijlstra authored
commit 5de2755c upstream. Because we drop cpu_base->lock around calling hrtimer::function, it is possible for hrtimer_start() to come in between and enqueue the timer. If hrtimer::function then returns HRTIMER_RESTART we'll hit the BUG_ON because HRTIMER_STATE_ENQUEUED will be set. Since the above is a perfectly valid scenario, remove the BUG_ON and make the enqueue_hrtimer() call conditional on the timer not being enqueued already. NOTE: in that concurrent scenario its entirely common for both sites to want to modify the hrtimer, since hrtimers don't provide serialization themselves be sure to provide some such that the hrtimer::function and the hrtimer_start() caller don't both try and fudge the expiration state at the same time. To that effect, add a WARN when someone tries to forward an already enqueued timer, the most common way to change the expiry of self restarting timers. Ideally we'd put the WARN in everything modifying the expiry but most of that is inlines and we don't need the bloat. Fixes: 2d44ae4d ("hrtimer: clean up cpu->base locking tricks") Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ben Segall <bsegall@google.com> Cc: Roman Gushchin <klamm@yandex-team.ru> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20150415113105.GT5029@twins.programming.kicks-ass.netSigned-off-by:
Thomas Gleixner <tglx@linutronix.de> [bwh: Backported to 3.2: adjust filename, context] Signed-off-by:
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Lars Persson authored
commit 4d46a67a upstream. The lazy cache flushing implemented in the MIPS kernel suffers from a race condition that is exposed by do_set_pte() in mm/memory.c. A pre-condition is a file-system that writes to the page from the CPU in its readpage method and then calls flush_dcache_page(). One example is ubifs. Another pre-condition is that the dcache flush is postponed in __flush_dcache_page(). Upon a page fault for an executable mapping not existing in the page-cache, the following will happen: 1. Write to the page 2. flush_dcache_page 3. flush_icache_page 4. set_pte_at 5. update_mmu_cache (commits the flush of a dcache-dirty page) Between steps 4 and 5 another thread can hit the same page and it will encounter a valid pte. Because the data still is in the L1 dcache the CPU will fetch stale data from L2 into the icache and execute garbage. This fix moves the commit of the cache flush to step 3 to close the race window. It also reduces the amount of flushes on non-executable mappings because we never enter __flush_dcache_page() for non-aliasing CPUs. Regressions can occur in drivers that mistakenly relies on the flush_dcache_page() in get_user_pages() for DMA operations. [ralf@linux-mips.org: Folded in patch 9346 to fix highmem issue.] Signed-off-by:
Lars Persson <larper@axis.com> Cc: linux-mips@linux-mips.org Cc: paul.burton@imgtec.com Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9346/ Patchwork: https://patchwork.linux-mips.org/patch/9738/Signed-off-by:
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Alexander Sverdlin authored
commit 73bf3c2a upstream. udelay() in PCI/PCIe read/write callbacks cause 30ms IRQ latency on Octeon platforms because these operations are called from PCI_OP_READ() and PCI_OP_WRITE() under raw_spin_lock_irqsave(). Signed-off-by:
Alexander Sverdlin <alexander.sverdlin@nokia.com> Cc: linux-mips@linux-mips.org Cc: David Daney <ddaney@cavium.com> Cc: Rob Herring <robh@kernel.org> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Masanari Iida <standby24x7@gmail.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Mathias <mathias.rulf@nokia.com> Patchwork: https://patchwork.linux-mips.org/patch/9576/Signed-off-by:
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Mark Grondona authored
commit 73af963f upstream. __ptrace_may_access() checks get_dumpable/ptrace_has_cap/etc if task != current, this can can lead to surprising results. For example, a sub-thread can't readlink("/proc/self/exe") if the executable is not readable. setup_new_exec()->would_dump() notices that inode_permission(MAY_READ) fails and then it does set_dumpable(suid_dumpable). After that get_dumpable() fails. (It is not clear why proc_pid_readlink() checks get_dumpable(), perhaps we could add PTRACE_MODE_NODUMPABLE) Change __ptrace_may_access() to use same_thread_group() instead of "task == current". Any security check is pointless when the tasks share the same ->mm. Signed-off-by:
Mark Grondona <mgrondona@llnl.gov> Signed-off-by:
Ben Woodard <woodard@redhat.com> Signed-off-by:
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Oleg Nesterov authored
commit e1403b8e upstream. task_struct->pid/tgid should go away. 1. Change same_thread_group() to use task->signal for comparison. 2. Change has_group_leader_pid(task) to compare task_pid(task) with signal->leader_pid. Signed-off-by:
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Feng Tang authored
commit 55c844a4 upstream. When rebooting our 24 CPU Westmere servers with 3.4-rc6, we always see this warning msg: Restarting system. machine restart ------------[ cut here ]------------ WARNING: at arch/x86/kernel/smp.c:125 native_smp_send_reschedule+0x74/0xa7() Hardware name: X8DTN Modules linked in: igb [last unloaded: scsi_wait_scan] Pid: 1, comm: systemd-shutdow Not tainted 3.4.0-rc6+ #22 Call Trace: <IRQ> [<ffffffff8102a41f>] warn_slowpath_common+0x7e/0x96 [<ffffffff8102a44c>] warn_slowpath_null+0x15/0x17 [<ffffffff81018cf7>] native_smp_send_reschedule+0x74/0xa7 [<ffffffff810561c1>] trigger_load_balance+0x279/0x2a6 [<ffffffff81050112>] scheduler_tick+0xe0/0xe9 [<ffffffff81036768>] update_process_times+0x60/0x70 [<ffffffff81062f2f>] tick_sched_timer+0x68/0x92 [<ffffffff81046e33>] __run_hrtimer+0xb3/0x13c [<ffffffff81062ec7>] ? tick_nohz_handler+0xd0/0xd0 [<ffffffff810474f2>] hrtimer_interrupt+0xdb/0x198 [<ffffffff81019a35>] smp_apic_timer_interrupt+0x81/0x94 [<ffffffff81655187>] apic_timer_interrupt+0x67/0x70 <EOI> [<ffffffff8101a3c4>] ? default_send_IPI_mask_allbutself_phys+0xb4/0xc4 [<ffffffff8101c680>] physflat_send_IPI_allbutself+0x12/0x14 [<ffffffff81018db4>] native_nmi_stop_other_cpus+0x8a/0xd6 [<ffffffff810188ba>] native_machine_shutdown+0x50/0x67 [<ffffffff81018926>] machine_shutdown+0xa/0xc [<ffffffff8101897e>] native_machine_restart+0x20/0x32 [<ffffffff810189b0>] machine_restart+0xa/0xc [<ffffffff8103b196>] kernel_restart+0x47/0x4c [<ffffffff8103b2e6>] sys_reboot+0x13e/0x17c [<ffffffff8164e436>] ? _raw_spin_unlock_bh+0x10/0x12 [<ffffffff810fcac9>] ? bdi_queue_work+0xcf/0xd8 [<ffffffff810fe82f>] ? __bdi_start_writeback+0xae/0xb7 [<ffffffff810e0d64>] ? iterate_supers+0xa3/0xb7 [<ffffffff816547a2>] system_call_fastpath+0x16/0x1b ---[ end trace 320af5cb1cb60c5b ]--- The root cause seems to be the default_send_IPI_mask_allbutself_phys() takes quite some time (I measured it could be several ms) to complete sending NMIs to all the other 23 CPUs, and for HZ=250/1000 system, the time is long enough for a timer interrupt to happen, which will in turn trigger to kick load balance to a stopped CPU and cause this warning in native_smp_send_reschedule(). So disabling the local irq before stop_other_cpu() can fix this problem (tested 25 times reboot ok), and it is fine as there should be nobody caring the timer interrupt in such reboot stage. The latest 3.4 kernel slightly changes this behavior by sending REBOOT_VECTOR first and only send NMI_VECTOR if the REBOOT_VCTOR fails, and this patch is still needed to prevent the problem. Signed-off-by:
Feng Tang <feng.tang@intel.com> Acked-by:
Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120530231541.4c13433a@feng-i7Signed-off-by:
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Steven Rostedt authored
commit 2cf30dc1 upstream. When the following filter is used it causes a warning to trigger: # cd /sys/kernel/debug/tracing # echo "((dev==1)blocks==2)" > events/ext4/ext4_truncate_exit/filter -bash: echo: write error: Invalid argument # cat events/ext4/ext4_truncate_exit/filter ((dev==1)blocks==2) ^ parse_error: No error ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1223 at kernel/trace/trace_events_filter.c:1640 replace_preds+0x3c5/0x990() Modules linked in: bnep lockd grace bluetooth ... CPU: 3 PID: 1223 Comm: bash Tainted: G W 4.1.0-rc3-test+ #450 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012 0000000000000668 ffff8800c106bc98 ffffffff816ed4f9 ffff88011ead0cf0 0000000000000000 ffff8800c106bcd8 ffffffff8107fb07 ffffffff8136b46c ffff8800c7d81d48 ffff8800d4c2bc00 ffff8800d4d4f920 00000000ffffffea Call Trace: [<ffffffff816ed4f9>] dump_stack+0x4c/0x6e [<ffffffff8107fb07>] warn_slowpath_common+0x97/0xe0 [<ffffffff8136b46c>] ? _kstrtoull+0x2c/0x80 [<ffffffff8107fb6a>] warn_slowpath_null+0x1a/0x20 [<ffffffff81159065>] replace_preds+0x3c5/0x990 [<ffffffff811596b2>] create_filter+0x82/0xb0 [<ffffffff81159944>] apply_event_filter+0xd4/0x180 [<ffffffff81152bbf>] event_filter_write+0x8f/0x120 [<ffffffff811db2a8>] __vfs_write+0x28/0xe0 [<ffffffff811dda43>] ? __sb_start_write+0x53/0xf0 [<ffffffff812e51e0>] ? security_file_permission+0x30/0xc0 [<ffffffff811dc408>] vfs_write+0xb8/0x1b0 [<ffffffff811dc72f>] SyS_write+0x4f/0xb0 [<ffffffff816f5217>] system_call_fastpath+0x12/0x6a ---[ end trace e11028bd95818dcd ]--- Worse yet, reading the error message (the filter again) it says that there was no error, when there clearly was. The issue is that the code that checks the input does not check for balanced ops. That is, having an op between a closed parenthesis and the next token. This would only cause a warning, and fail out before doing any real harm, but it should still not caues a warning, and the error reported should work: # cd /sys/kernel/debug/tracing # echo "((dev==1)blocks==2)" > events/ext4/ext4_truncate_exit/filter -bash: echo: write error: Invalid argument # cat events/ext4/ext4_truncate_exit/filter ((dev==1)blocks==2) ^ parse_error: Meaningless filter expression And give no kernel warning. Link: http://lkml.kernel.org/r/20150615175025.7e809215@gandalf.local.home Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Reported-by:
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Ben Hutchings authored
Inspired by commit f18c34e4 ("lib: Fix strnlen_user() to not touch memory after specified maximum") upstream. This version of strnlen_user(), no longer present upstream, has a similar off-by-one error. Signed-off-by:
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