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2018-09-089p: embed fcall in req to round down buffer allocsDominique Martinet
'msize' is often a power of two, or at least page-aligned, so avoiding an overhead of two dozen bytes for each allocation will help the allocator do its work and reduce memory fragmentation. Link: http://lkml.kernel.org/r/1533825236-22896-1-git-send-email-asmadeus@codewreck.org Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr> Reviewed-by: Greg Kurz <groug@kaod.org> Acked-by: Jun Piao <piaojun@huawei.com> Cc: Matthew Wilcox <willy@infradead.org>
2018-08-299p: Remove p9_idpoolMatthew Wilcox
There are no more users left of the p9_idpool; delete it. Link: http://lkml.kernel.org/r/20180711210225.19730-7-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-299p: Use a slab for allocating requestsMatthew Wilcox
Replace the custom batch allocation with a slab. Use an IDR to store pointers to the active requests instead of an array. We don't try to handle P9_NOTAG specially; the IDR will happily shrink all the way back once the TVERSION call has completed. Link: http://lkml.kernel.org/r/20180711210225.19730-6-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-299p: clear dangling pointers in p9stat_freeDominique Martinet
p9stat_free is more of a cleanup function than a 'free' function as it only frees the content of the struct; there are chances of use-after-free if it is improperly used (e.g. p9stat_free called twice as it used to be possible to) Clearing dangling pointers makes the function idempotent and safer to use. Link: http://lkml.kernel.org/r/1535410108-20650-2-git-send-email-asmadeus@codewreck.org Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr> Reported-by: syzbot+d4252148d198410b864f@syzkaller.appspotmail.com
2018-08-279p/xen: fix check for xenbus_read error in front_probeDominique Martinet
If the xen bus exists but does not expose the proper interface, it is possible to get a non-zero length but still some error, leading to strcmp failing trying to load invalid memory addresses e.g. fffffffffffffffe. There is then no need to check length when there is no error, as the xenbus driver guarantees that the string is nul-terminated. Link: http://lkml.kernel.org/r/1534236007-10170-1-git-send-email-asmadeus@codewreck.org Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Latchesar Ionkov <lucho@ionkov.net>
2018-08-17Merge tag '9p-for-4.19-2' of git://github.com/martinetd/linuxLinus Torvalds
Pull 9p updates from Dominique Martinet: "This contains mostly fixes (6 to be backported to stable) and a few changes, here is the breakdown: - rework how fids are attributed by replacing some custom tracking in a list by an idr - for packet-based transports (virtio/rdma) validate that the packet length matches what the header says - a few race condition fixes found by syzkaller - missing argument check when NULL device is passed in sys_mount - a few virtio fixes - some spelling and style fixes" * tag '9p-for-4.19-2' of git://github.com/martinetd/linux: (21 commits) net/9p/trans_virtio.c: add null terminal for mount tag 9p/virtio: fix off-by-one error in sg list bounds check 9p: fix whitespace issues 9p: fix multiple NULL-pointer-dereferences fs/9p/xattr.c: catch the error of p9_client_clunk when setting xattr failed 9p: validate PDU length net/9p/trans_fd.c: fix race by holding the lock net/9p/trans_fd.c: fix race-condition by flushing workqueue before the kfree() net/9p/virtio: Fix hard lockup in req_done net/9p/trans_virtio.c: fix some spell mistakes in comments 9p/net: Fix zero-copy path in the 9p virtio transport 9p: Embed wait_queue_head into p9_req_t 9p: Replace the fidlist with an IDR 9p: Change p9_fid_create calling convention 9p: Fix comment on smp_wmb net/9p/client.c: version pointer uninitialized fs/9p/v9fs.c: fix spelling mistake "Uknown" -> "Unknown" net/9p: fix error path of p9_virtio_probe 9p/net/protocol.c: return -ENOMEM when kmalloc() failed net/9p/client.c: add missing '\n' at the end of p9_debug() ...
2018-08-16Merge branch 'linus/master' into rdma.git for-nextJason Gunthorpe
rdma.git merge resolution for the 4.19 merge window Conflicts: drivers/infiniband/core/rdma_core.c - Use the rdma code and revise with the new spelling for atomic_fetch_add_unless drivers/nvme/host/rdma.c - Replace max_sge with max_send_sge in new blk code drivers/nvme/target/rdma.c - Use the blk code and revise to use NULL for ib_post_recv when appropriate - Replace max_sge with max_recv_sge in new blk code net/rds/ib_send.c - Use the net code and revise to use NULL for ib_post_recv when appropriate Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-08-16Merge tag 'v4.18' into rdma.git for-nextJason Gunthorpe
Resolve merge conflicts from the -rc cycle against the rdma.git tree: Conflicts: drivers/infiniband/core/uverbs_cmd.c - New ifs added to ib_uverbs_ex_create_flow in -rc and for-next - Merge removal of file->ucontext in for-next with new code in -rc drivers/infiniband/core/uverbs_main.c - for-next removed code from ib_uverbs_write() that was modified in for-rc Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-08-13net/9p/trans_virtio.c: add null terminal for mount tagpiaojun
chan->tag is Non-null terminated which will result in printing messy code when debugging code. So we should add '\0' for tag to make the code more convenient and robust. In addition, I drop char->tag_len to simplify the code. Link: http://lkml.kernel.org/r/5B641ECC.5030401@huawei.com Signed-off-by: Jun Piao <piaojun@huawei.com> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p/virtio: fix off-by-one error in sg list bounds checkjiangyiwen
Because the value of limit is VIRTQUEUE_NUM, if index is equal to limit, it will cause sg array out of bounds, so correct the judgement of BUG_ON. Link: http://lkml.kernel.org/r/5B63D5F6.6080109@huawei.com Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com> Reported-By: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Jun Piao <piaojun@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p: fix whitespace issuesStephen Hemminger
Remove trailing whitespace and blank lines at EOF Link: http://lkml.kernel.org/m/20180724192918.31165-11-sthemmin@microsoft.com Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p: fix multiple NULL-pointer-dereferencesTomas Bortoli
Added checks to prevent GPFs from raising. Link: http://lkml.kernel.org/r/20180727110558.5479-1-tomasbortoli@gmail.com Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com> Reported-by: syzbot+1a262da37d3bead15c39@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p: validate PDU lengthTomas Bortoli
This commit adds length check for the PDU size. The size contained in the header has to match the actual size, except for TCP (trans_fd.c) where actual length is not known ahead and the header's length will be checked only against the validity range. Link: http://lkml.kernel.org/r/20180723154404.2406-1-tomasbortoli@gmail.com Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com> Reported-by: syzbot+65c6b72f284a39d416b4@syzkaller.appspotmail.com To: Eric Van Hensbergen <ericvh@gmail.com> To: Ron Minnich <rminnich@sandia.gov> To: Latchesar Ionkov <lucho@ionkov.net> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13net/9p/trans_fd.c: fix race by holding the lockTomas Bortoli
It may be possible to run p9_fd_cancel() with a deleted req->req_list and incur in a double del. To fix hold the client->lock while changing the status, so the other threads will be synchronized. Link: http://lkml.kernel.org/r/20180723184253.6682-1-tomasbortoli@gmail.com Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com> Reported-by: syzbot+735d926e9d1317c3310c@syzkaller.appspotmail.com To: Eric Van Hensbergen <ericvh@gmail.com> To: Ron Minnich <rminnich@sandia.gov> To: Latchesar Ionkov <lucho@ionkov.net> Cc: Yiwen Jiang <jiangyiwen@huwei.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13net/9p/trans_fd.c: fix race-condition by flushing workqueue before the kfree()Tomas Bortoli
The patch adds the flush in p9_mux_poll_stop() as it the function used by p9_conn_destroy(), in turn called by p9_fd_close() to stop the async polling associated with the data regarding the connection. Link: http://lkml.kernel.org/r/20180720092730.27104-1-tomasbortoli@gmail.com Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com> Reported-by: syzbot+39749ed7d9ef6dfb23f6@syzkaller.appspotmail.com To: Eric Van Hensbergen <ericvh@gmail.com> To: Ron Minnich <rminnich@sandia.gov> To: Latchesar Ionkov <lucho@ionkov.net> Cc: Yiwen Jiang <jiangyiwen@huwei.com> Cc: stable@vger.kernel.org Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13net/9p/virtio: Fix hard lockup in req_donejiangyiwen
When client has multiple threads that issue io requests all the time, and the server has a very good performance, it may cause cpu is running in the irq context for a long time because it can check virtqueue has buf in the *while* loop. So we should keep chan->lock in the whole loop. [ Dominique: reworded subject line ] Link: http://lkml.kernel.org/r/5B503AEC.5080404@huawei.com Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com> To: Andrew Morton <akpm@linux-foundation.org> To: Eric Van Hensbergen <ericvh@gmail.com> To: Ron Minnich <rminnich@sandia.gov> To: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13net/9p/trans_virtio.c: fix some spell mistakes in commentspiaojun
Fix spelling mistake in comments of p9_virtio_zc_request(). Link: http://lkml.kernel.org/r/5B4EB7D9.9010108@huawei.com Signed-off-by: Jun Piao <piaojun@huawei.com> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p/net: Fix zero-copy path in the 9p virtio transportChirantan Ekbote
The zero-copy optimization when reading or writing large chunks of data is quite useful. However, the 9p messages created through the zero-copy write path have an incorrect message size: it should be the size of the header + size of the data being written but instead it's just the size of the header. This only works if the server ignores the size field of the message and otherwise breaks the framing of the protocol. Fix this by re-writing the message size field with the correct value. Tested by running `dd if=/dev/zero of=out bs=4k count=1` inside a virtio-9p mount. Link: http://lkml.kernel.org/r/20180717003529.114368-1-chirantan@chromium.org Signed-off-by: Chirantan Ekbote <chirantan@chromium.org> Reviewed-by: Greg Kurz <groug@kaod.org> Tested-by: Greg Kurz <groug@kaod.org> Cc: Dylan Reid <dgreid@chromium.org> Cc: Guenter Roeck <groeck@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p: Embed wait_queue_head into p9_req_tMatthew Wilcox
On a 64-bit system, the wait_queue_head_t is 24 bytes while the pointer to it is 8 bytes. Growing the p9_req_t by 16 bytes is better than performing a 24-byte memory allocation. Link: http://lkml.kernel.org/r/20180711210225.19730-5-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Greg Kurz <groug@kaod.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p: Replace the fidlist with an IDRMatthew Wilcox
The p9_idpool being used to allocate the IDs uses an IDR to allocate the IDs ... which we then keep in a doubly-linked list, rather than in the IDR which allocated them. We can use an IDR directly which saves two pointers per p9_fid, and a tiny memory allocation per p9_client. Link: http://lkml.kernel.org/r/20180711210225.19730-4-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p: Change p9_fid_create calling conventionMatthew Wilcox
Return NULL instead of ERR_PTR when we can't allocate a FID. The ENOSPC return value was getting all the way back to userspace, and that's confusing for a userspace program which isn't expecting read() to tell it there's no space left on the filesystem. The best error we can return to indicate a temporary failure caused by lack of client resources is ENOMEM. Maybe it would be better to sleep until a FID is available, but that's not a change I'm comfortable making. Link: http://lkml.kernel.org/r/20180711210225.19730-3-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Jun Piao <piaojun@huawei.com> Reviewed-by: Greg Kurz <groug@kaod.org> Reviewed-by: Yiwen Jiang <jiangyiwen@huwei.com> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p: Fix comment on smp_wmbMatthew Wilcox
The previous comment misled me into thinking the barrier wasn't needed at all. Link: http://lkml.kernel.org/r/20180711210225.19730-2-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Greg Kurz <groug@kaod.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13net/9p/client.c: version pointer uninitializedTomas Bortoli
The p9_client_version() does not initialize the version pointer. If the call to p9pdu_readf() returns an error and version has not been allocated in p9pdu_readf(), then the program will jump to the "error" label and will try to free the version pointer. If version is not initialized, free() will be called with uninitialized, garbage data and will provoke a crash. Link: http://lkml.kernel.org/r/20180709222943.19503-1-tomasbortoli@gmail.com Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com> Reported-by: syzbot+65c6b72f284a39d416b4@syzkaller.appspotmail.com Reviewed-by: Jun Piao <piaojun@huawei.com> Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13net/9p: fix error path of p9_virtio_probeJean-Philippe Brucker
Currently when virtio_find_single_vq fails, we go through del_vqs which throws a warning (Trying to free already-free IRQ). Skip del_vqs if vq allocation failed. Link: http://lkml.kernel.org/r/20180524101021.49880-1-jean-philippe.brucker@arm.com Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Reviewed-by: Greg Kurz <groug@kaod.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-139p/net/protocol.c: return -ENOMEM when kmalloc() failedpiaojun
We should return -ENOMEM to upper user when kmalloc failed to indicate accurate errno. Link: http://lkml.kernel.org/r/5B4552C5.60000@huawei.com Signed-off-by: Jun Piao <piaojun@huawei.com> Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13net/9p/client.c: add missing '\n' at the end of p9_debug()piaojun
In p9_client_getattr_dotl(), we should add '\n' at the end of printing log. Link: http://lkml.kernel.org/r/5B44589A.50302@huawei.com Signed-off-by: Jun Piao <piaojun@huawei.com> Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-08net:mod: remove unneeded variable 'ret' in init_p9zhong jiang
The ret is modified after initalization, so just remove it and return 0. Signed-off-by: zhong jiang <zhongjiang@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24net/9p: Simplify ib_post_(send|recv|srq_recv)() callsBart Van Assche
Instead of declaring and passing a dummy 'bad_wr' pointer, pass NULL as third argument to ib_post_(send|recv|srq_recv)(). Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-07-14net/9p/client.c: put refcount of trans_mod in error case in parse_opts()piaojun
In my testing, the second mount will fail after umounting successfully. The reason is that we put refcount of trans_mod in the correct case rather than the error case in parse_opts() at last. That will cause the refcount decrease to -1, and when we try to get trans_mod again in try_module_get(), we could only increase refcount to 0 which will cause failure as follows: parse_opts v9fs_get_trans_by_name try_module_get : return NULL to caller which cause error So we should put refcount of trans_mod in error case. Link: http://lkml.kernel.org/r/5B3F39A0.2030509@huawei.com Fixes: 9421c3e64137ec ("net/9p/client.c: fix potential refcnt problem of trans module") Signed-off-by: Jun Piao <piaojun@huawei.com> Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com> Reviewed-by: Greg Kurz <groug@kaod.org> Reviewed-by: Dominique Martinet <dominique.martinet@cea.fr> Tested-by: Dominique Martinet <dominique.martinet@cea.fr> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-12treewide: kmalloc() -> kmalloc_array()Kees Cook
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-07net/9p/trans_xen.c: don't inclide rwlock.h directlySebastian Andrzej Siewior
rwlock.h should not be included directly. Instead linux/splinlock.h should be included. One thing it does is to break the RT build. Link: http://lkml.kernel.org/r/20180504100319.11880-1-bigeasy@linutronix.de Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07net/9p: detect invalid options as much as possibleChengguang Xu
Currently when detecting invalid options in option parsing, some options(e.g. msize) just set errno and allow to continuously validate other options so that it can detect invalid options as much as possible and give proper error messages together. This patch applies same rule to option 'trans' and 'version' when detecting -EINVAL. Link: http://lkml.kernel.org/r/1525340676-34072-1-git-send-email-cgxu519@gmx.com Signed-off-by: Chengguang Xu <cgxu519@gmx.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Add Maglev hashing scheduler to IPVS, from Inju Song. 2) Lots of new TC subsystem tests from Roman Mashak. 3) Add TCP zero copy receive and fix delayed acks and autotuning with SO_RCVLOWAT, from Eric Dumazet. 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard Brouer. 5) Add ttl inherit support to vxlan, from Hangbin Liu. 6) Properly separate ipv6 routes into their logically independant components. fib6_info for the routing table, and fib6_nh for sets of nexthops, which thus can be shared. From David Ahern. 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP messages from XDP programs. From Nikita V. Shirokov. 8) Lots of long overdue cleanups to the r8169 driver, from Heiner Kallweit. 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau. 10) Add traffic condition monitoring to iwlwifi, from Luca Coelho. 11) Plumb extack down into fib_rules, from Roopa Prabhu. 12) Add Flower classifier offload support to igb, from Vinicius Costa Gomes. 13) Add UDP GSO support, from Willem de Bruijn. 14) Add documentation for eBPF helpers, from Quentin Monnet. 15) Add TLS tx offload to mlx5, from Ilya Lesokhin. 16) Allow applications to be given the number of bytes available to read on a socket via a control message returned from recvmsg(), from Soheil Hassas Yeganeh. 17) Add x86_32 eBPF JIT compiler, from Wang YanQing. 18) Add AF_XDP sockets, with zerocopy support infrastructure as well. From Björn Töpel. 19) Remove indirect load support from all of the BPF JITs and handle these operations in the verifier by translating them into native BPF instead. From Daniel Borkmann. 20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha. 21) Allow XDP programs to do lookups in the main kernel routing tables for forwarding. From David Ahern. 22) Allow drivers to store hardware state into an ELF section of kernel dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy. 23) Various RACK and loss detection improvements in TCP, from Yuchung Cheng. 24) Add TCP SACK compression, from Eric Dumazet. 25) Add User Mode Helper support and basic bpfilter infrastructure, from Alexei Starovoitov. 26) Support ports and protocol values in RTM_GETROUTE, from Roopa Prabhu. 27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard Brouer. 28) Add lots of forwarding selftests, from Petr Machata. 29) Add generic network device failover driver, from Sridhar Samudrala. * ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits) strparser: Add __strp_unpause and use it in ktls. rxrpc: Fix terminal retransmission connection ID to include the channel net: hns3: Optimize PF CMDQ interrupt switching process net: hns3: Fix for VF mailbox receiving unknown message net: hns3: Fix for VF mailbox cannot receiving PF response bnx2x: use the right constant Revert "net: sched: cls: Fix offloading when ingress dev is vxlan" net: dsa: b53: Fix for brcm tag issue in Cygnus SoC enic: fix UDP rss bits netdev-FAQ: clarify DaveM's position for stable backports rtnetlink: validate attributes in do_setlink() mlxsw: Add extack messages for port_{un, }split failures netdevsim: Add extack error message for devlink reload devlink: Add extack to reload and port_{un, }split operations net: metrics: add proper netlink validation ipmr: fix error path when ipmr_new_table fails ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds net: hns3: remove unused hclgevf_cfg_func_mta_filter netfilter: provide udp*_lib_lookup for nf_tproxy qed*: Utilize FW 8.37.2.0 ...
2018-06-04Merge branch 'work.aio-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull aio updates from Al Viro: "Majority of AIO stuff this cycle. aio-fsync and aio-poll, mostly. The only thing I'm holding back for a day or so is Adam's aio ioprio - his last-minute fixup is trivial (missing stub in !CONFIG_BLOCK case), but let it sit in -next for decency sake..." * 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) aio: sanitize the limit checking in io_submit(2) aio: fold do_io_submit() into callers aio: shift copyin of iocb into io_submit_one() aio_read_events_ring(): make a bit more readable aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way aio: take list removal to (some) callers of aio_complete() aio: add missing break for the IOCB_CMD_FDSYNC case random: convert to ->poll_mask timerfd: convert to ->poll_mask eventfd: switch to ->poll_mask pipe: convert to ->poll_mask crypto: af_alg: convert to ->poll_mask net/rxrpc: convert to ->poll_mask net/iucv: convert to ->poll_mask net/phonet: convert to ->poll_mask net/nfc: convert to ->poll_mask net/caif: convert to ->poll_mask net/bluetooth: convert to ->poll_mask net/sctp: convert to ->poll_mask net/tipc: convert to ->poll_mask ...
2018-06-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Filling in the padding slot in the bpf structure as a bug fix in 'ne' overlapped with actually using that padding area for something in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds
Pull rdma fixes from Jason Gunthorpe: "Just three small last minute regressions that were found in the last week. The Broadcom fix is a bit big for rc7, but since it is fixing driver crash regressions that were merged via netdev into rc1, I am sending it. - bnxt netdev changes merged this cycle caused the bnxt RDMA driver to crash under certain situations - Arnd found (several, unfortunately) kconfig problems with the patches adding INFINIBAND_ADDR_TRANS. Reverting this last part, will fix it more fully outside -rc. - Subtle change in error code for a uapi function caused breakage in userspace. This was bug was subtly introduced cycle" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: IB/core: Fix error code for invalid GID entry IB: Revert "remove redundant INFINIBAND kconfig dependencies" RDMA/bnxt_re: Fix broken RoCE driver due to recent L2 driver changes
2018-05-28IB: Revert "remove redundant INFINIBAND kconfig dependencies"Arnd Bergmann
Several subsystems depend on INFINIBAND_ADDR_TRANS, which in turn depends on INFINIBAND. However, when with CONFIG_INIFIBAND=m, this leads to a link error when another driver using it is built-in. The INFINIBAND_ADDR_TRANS dependency is insufficient here as this is a 'bool' symbol that does not force anything to be a module in turn. fs/cifs/smbdirect.o: In function `smbd_disconnect_rdma_work': smbdirect.c:(.text+0x1e4): undefined reference to `rdma_disconnect' net/9p/trans_rdma.o: In function `rdma_request': trans_rdma.c:(.text+0x7bc): undefined reference to `rdma_disconnect' net/9p/trans_rdma.o: In function `rdma_destroy_trans': trans_rdma.c:(.text+0x830): undefined reference to `ib_destroy_qp' trans_rdma.c:(.text+0x858): undefined reference to `ib_dealloc_pd' Fixes: 9533b292a7ac ("IB: remove redundant INFINIBAND kconfig dependencies") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Thelen <gthelen@google.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-05-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Lots of easy overlapping changes in the confict resolutions here. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-26fs: add new vfs_poll and file_can_poll helpersChristoph Hellwig
These abstract out calls to the poll method in preparation for changes in how we poll. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-24Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds
Pull rdma fixes from Jason Gunthorpe: "This is pretty much just the usual array of smallish driver bugs. - remove bouncing addresses from the MAINTAINERS file - kernel oops and bad error handling fixes for hfi, i40iw, cxgb4, and hns drivers - various small LOC behavioral/operational bugs in mlx5, hns, qedr and i40iw drivers - two fixes for patches already sent during the merge window - a long-standing bug related to not decreasing the pinned pages count in the right MM was found and fixed" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (28 commits) RDMA/hns: Move the location for initializing tmp_len RDMA/hns: Bugfix for cq record db for kernel IB/uverbs: Fix uverbs_attr_get_obj RDMA/qedr: Fix doorbell bar mapping for dpi > 1 IB/umem: Use the correct mm during ib_umem_release iw_cxgb4: Fix an error handling path in 'c4iw_get_dma_mr()' RDMA/i40iw: Avoid panic when reading back the IRQ affinity hint RDMA/i40iw: Avoid reference leaks when processing the AEQ RDMA/i40iw: Avoid panic when objects are being created and destroyed RDMA/hns: Fix the bug with NULL pointer RDMA/hns: Set NULL for __internal_mr RDMA/hns: Enable inner_pa_vld filed of mpt RDMA/hns: Set desc_dma_addr for zero when free cmq desc RDMA/hns: Fix the bug with rq sge RDMA/hns: Not support qp transition from reset to reset for hip06 RDMA/hns: Add return operation when configured global param fail RDMA/hns: Update convert function of endian format RDMA/hns: Load the RoCE dirver automatically RDMA/hns: Bugfix for rq record db for kernel RDMA/hns: Add rq inline flags judgement ...
2018-05-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
The bpf syscall and selftests conflicts were trivial overlapping changes. The r8169 change involved moving the added mdelay from 'net' into a different function. A TLS close bug fix overlapped with the splitting of the TLS state into separate TX and RX parts. I just expanded the tests in the bug fix from "ctx->conf == X" into "ctx->tx_conf == X && ctx->rx_conf == X". Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-10net/9p: fix spelling mistake: "suspsend" -> "suspend"Colin Ian King
Trivial fix to spelling mistake in dev_warn message text Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-10net/9p: correct some comment errors in 9p file system codeSun Lianwen
There are follow comment errors: 1 The function name is wrong in p9_release_pages() comment. 2 The function name and variable name is wrong in p9_poll_workfn() comment. 3 There is no variable dm_mr and lkey in struct p9_trans_rdma. 4 The function name is wrong in rdma_create_trans() comment. 5 There is no variable initialized in struct virtio_chan. 6 The variable name is wrong in p9_virtio_zc_request() comment. Signed-off-by: Sun Lianwen <sunlw.fnst@cn.fujitsu.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-09IB: remove redundant INFINIBAND kconfig dependenciesGreg Thelen
INFINIBAND_ADDR_TRANS depends on INFINIBAND. So there's no need for options which depend INFINIBAND_ADDR_TRANS to also depend on INFINIBAND. Remove the unnecessary INFINIBAND depends. Signed-off-by: Greg Thelen <gthelen@google.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-05-07net/9p: correct the variable name in v9fs_get_trans_by_name() commentSun Lianwen
The v9fs_get_trans_by_name(char *s) variable name is not "name" but "s". Signed-off-by: Sun Lianwen <sunlw.fnst@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-05net/9p/client.c: fix potential refcnt problem of trans moduleChengguang Xu
When specifying trans_mod multiple times in a mount, it will cause an inaccurate refcount of the trans module. Also, in the error case of option parsing, we should put the trans module if we have already got it. Link: http://lkml.kernel.org/r/1522154942-57339-1-git-send-email-cgxu519@gmx.com Signed-off-by: Chengguang Xu <cgxu519@gmx.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Miller <davem@davemloft.net> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05net/9p: avoid -ERESTARTSYS leak to userspaceGreg Kurz
If it was interrupted by a signal, the 9p client may need to send some more requests to the server for cleanup before returning to userspace. To avoid such a last minute request to be interrupted right away, the client memorizes if a signal is pending, clears TIF_SIGPENDING, handles the request and calls recalc_sigpending() before returning. Unfortunately, if the transmission of this cleanup request fails for any reason, the transport returns an error and the client propagates it right away, without calling recalc_sigpending(). This ends up with -ERESTARTSYS from the initially interrupted request crawling up to syscall exit, with TIF_SIGPENDING cleared by the cleanup request. The specific signal handling code, which is responsible for converting -ERESTARTSYS to -EINTR is not called, and userspace receives the confusing errno value: open: Unknown error 512 (512) This is really hard to hit in real life. I discovered the issue while working on hot-unplug of a virtio-9p-pci device with an instrumented QEMU allowing to control request completion. Both p9_client_zc_rpc() and p9_client_rpc() functions have this buggy error path actually. Their code flow is a bit obscure and the best thing to do would probably be a full rewrite: to really ensure this situation of clearing TIF_SIGPENDING and returning -ERESTARTSYS can never happen. But given the general lack of interest for the 9p code, I won't risk breaking more things. So this patch simply fixes the buggy paths in both functions with a trivial label+goto. Thanks to Laurent Dufour for his help and suggestions on how to find the root cause and how to fix it. Link: http://lkml.kernel.org/r/152062809886.10599.7361006774123053312.stgit@bahia.lan Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Cc: David Miller <davem@davemloft.net> Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-15Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio fixes from Michael Tsirkin: "This includes a bugfix for virtio 9p fs. It also fixes hybernation for s390 guests with virtio devices" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio/s390: implement PM operations for virtio_ccw 9p/trans_virtio: discard zero-length reply
2018-02-11vfs: do bulk POLL* -> EPOLL* replacementLinus Torvalds
This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-099p/trans_virtio: discard zero-length replyGreg Kurz
When a 9p request is successfully flushed, the server is expected to just mark it as used without sending a 9p reply (ie, without writing data into the buffer). In this case, virtqueue_get_buf() will return len == 0 and we must not report a REQ_STATUS_RCVD status to the client, otherwise the client will erroneously assume the request has not been flushed. Cc: stable@vger.kernel.org Signed-off-by: Greg Kurz <groug@kaod.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>