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* 9pfs: Fix divide by zero bugDan Schatzberg2019-11-231-2/+4
| | | | | | | | | | Some filesystems may return 0s in statfs (trivially, a FUSE filesystem can do so). QEMU should handle this gracefully and just behave the same as if statfs failed. Signed-off-by: Dan Schatzberg <dschatzberg@fb.com> Acked-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: Use variable length suffixes for inode remappingChristian Schoenebeck2019-10-102-33/+279
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use variable length suffixes for inode remapping instead of the fixed 16 bit size prefixes before. With this change the inode numbers on guest will typically be much smaller (e.g. around >2^1 .. >2^7 instead of >2^48 with the previous fixed size inode remapping. Additionally this solution is more efficient, since inode numbers in practice can take almost their entire 64 bit range on guest as well, so there is less likely a need for generating and tracking additional suffixes, which might also be beneficial for nested virtualization where each level of virtualization would shift up the inode bits and increase the chance of expensive remapping actions. The "Exponential Golomb" algorithm is used as basis for generating the variable length suffixes. The algorithm has a parameter k which controls the distribution of bits on increasing indeces (minimum bits at low index vs. maximum bits at high index). With k=0 the generated suffixes look like: Index Dec/Bin -> Generated Suffix Bin 1 [1] -> [1] (1 bits) 2 [10] -> [010] (3 bits) 3 [11] -> [110] (3 bits) 4 [100] -> [00100] (5 bits) 5 [101] -> [10100] (5 bits) 6 [110] -> [01100] (5 bits) 7 [111] -> [11100] (5 bits) 8 [1000] -> [0001000] (7 bits) 9 [1001] -> [1001000] (7 bits) 10 [1010] -> [0101000] (7 bits) 11 [1011] -> [1101000] (7 bits) 12 [1100] -> [0011000] (7 bits) ... 65533 [1111111111111101] -> [1011111111111111000000000000000] (31 bits) 65534 [1111111111111110] -> [0111111111111111000000000000000] (31 bits) 65535 [1111111111111111] -> [1111111111111111000000000000000] (31 bits) Hence minBits=1 maxBits=31 And with k=5 they would look like: Index Dec/Bin -> Generated Suffix Bin 1 [1] -> [000001] (6 bits) 2 [10] -> [100001] (6 bits) 3 [11] -> [010001] (6 bits) 4 [100] -> [110001] (6 bits) 5 [101] -> [001001] (6 bits) 6 [110] -> [101001] (6 bits) 7 [111] -> [011001] (6 bits) 8 [1000] -> [111001] (6 bits) 9 [1001] -> [000101] (6 bits) 10 [1010] -> [100101] (6 bits) 11 [1011] -> [010101] (6 bits) 12 [1100] -> [110101] (6 bits) ... 65533 [1111111111111101] -> [0011100000000000100000000000] (28 bits) 65534 [1111111111111110] -> [1011100000000000100000000000] (28 bits) 65535 [1111111111111111] -> [0111100000000000100000000000] (28 bits) Hence minBits=6 maxBits=28 Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: stat_to_qid: implement slow pathAntonios Motakis2019-10-102-7/+76
| | | | | | | | | | | | | | | | | | | | | | | | | | stat_to_qid attempts via qid_path_prefixmap to map unique files (which are identified by 64 bit inode nr and 32 bit device id) to a 64 QID path value. However this implementation makes some assumptions about inode number generation on the host. If qid_path_prefixmap fails, we still have 48 bits available in the QID path to fall back to a less memory efficient full mapping. Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com> [CS: - Rebased to https://github.com/gkurz/qemu/commits/9p-next (SHA1 7fc4c49e91). - Updated hash calls to new xxhash API. - Removed unnecessary parantheses in qpf_lookup_func(). - Removed unnecessary g_malloc0() result checks. - Log error message when running out of prefixes in qid_path_fullmap(). - Log warning message about potential degraded performance in qid_path_prefixmap(). - Wrapped qpf_table initialization to dedicated qpf_table_init() function. - Fixed typo in comment. ] Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: Added virtfs option 'multidevs=remap|forbid|warn'Antonios Motakis2019-10-103-21/+200
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'warn' (default): Only log an error message (once) on host if more than one device is shared by same export, except of that just ignore this config error though. This is the default behaviour for not breaking existing installations implying that they really know what they are doing. 'forbid': Like 'warn', but except of just logging an error this also denies access of guest to additional devices. 'remap': Allows to share more than one device per export by remapping inodes from host to guest appropriately. To support multiple devices on the 9p share, and avoid qid path collisions we take the device id as input to generate a unique QID path. The lowest 48 bits of the path will be set equal to the file inode, and the top bits will be uniquely assigned based on the top 16 bits of the inode and the device id. Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com> [CS: - Rebased to https://github.com/gkurz/qemu/commits/9p-next (SHA1 7fc4c49e91). - Added virtfs option 'multidevs', original patch simply did the inode remapping without being asked. - Updated hash calls to new xxhash API. - Updated docs for new option 'multidevs'. - Fixed v9fs_do_readdir() not having remapped inodes. - Log error message when running out of prefixes in qid_path_prefixmap(). - Fixed definition of QPATH_INO_MASK. - Wrapped qpp_table initialization to dedicated qpp_table_init() function. - Dropped unnecessary parantheses in qpp_lookup_func(). - Dropped unnecessary g_malloc0() result checks. ] Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> [groug: - Moved "multidevs" parsing to the local backend. - Added hint to invalid multidevs option error. - Turn "remap" into "x-remap". ] Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: Treat multiple devices on one export as an errorAntonios Motakis2019-10-102-14/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | The QID path should uniquely identify a file. However, the inode of a file is currently used as the QID path, which on its own only uniquely identifies files within a device. Here we track the device hosting the 9pfs share, in order to prevent security issues with QID path collisions from other devices. We only print a warning for now but a subsequent patch will allow users to have finer control over the desired behaviour. Failing the I/O will be one the proposed behaviour, so we also change stat_to_qid() to return an error here in order to keep other patches simpler. Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com> [CS: - Assign dev_id to export root's device already in v9fs_device_realize_common(), not postponed in stat_to_qid(). - error_report_once() if more than one device was shared by export. - Return -ENODEV instead of -ENOSYS in stat_to_qid(). - Fixed typo in log comment. ] Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> [groug, changed to warning, updated message and changelog] Signed-off-by: Greg Kurz <groug@kaod.org>
* fsdev: Add return value to fsdev_throttle_parse_opts()Greg Kurz2019-10-101-2/+1Star
| | | | | | | It is more convenient to use the return value of the function to notify errors, rather than to be tied up setting up the &local_err boilerplate. Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: Simplify error path of v9fs_device_realize_common()Greg Kurz2019-10-103-10/+14
| | | | | | | Make v9fs_device_unrealize_common() idempotent and use it for rollback, in order to reduce code duplication. Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: unsigned type for type, version, pathAntonios Motakis2019-10-102-10/+10
| | | | | | | | | | | There is no need for signedness on these QID fields for 9p. Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com> [CS: - Also make QID type unsigned. - Adjust donttouch_stat() to new types. - Adjust trace-events to new types. ] Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: simplify source file selectionPaolo Bonzini2019-08-201-0/+5
| | | | | | | | Express the complex conditions in Kconfig rather than Makefiles, since Kconfig is better suited at expressing dependencies and detecting contradictions. Cc: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Include hw/qdev-properties.h lessMarkus Armbruster2019-08-161-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | In my "build everything" tree, changing hw/qdev-properties.h triggers a recompile of some 2700 out of 6600 objects (not counting tests and objects that don't depend on qemu/osdep.h). Many places including hw/qdev-properties.h (directly or via hw/qdev.h) actually need only hw/qdev-core.h. Include hw/qdev-core.h there instead. hw/qdev.h is actually pointless: all it does is include hw/qdev-core.h and hw/qdev-properties.h, which in turn includes hw/qdev-core.h. Replace the remaining uses of hw/qdev.h by hw/qdev-properties.h. While there, delete a few superfluous inclusions of hw/qdev-core.h. Touching hw/qdev-properties.h now recompiles some 1200 objects. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Daniel P. Berrangé" <berrange@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com> Message-Id: <20190812052359.30071-22-armbru@redhat.com>
* Include qemu/main-loop.h lessMarkus Armbruster2019-08-168-1/+7
| | | | | | | | | | | | | | | | | | | | In my "build everything" tree, changing qemu/main-loop.h triggers a recompile of some 5600 out of 6600 objects (not counting tests and objects that don't depend on qemu/osdep.h). It includes block/aio.h, which in turn includes qemu/event_notifier.h, qemu/notify.h, qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h, qemu/thread.h, qemu/timer.h, and a few more. Include qemu/main-loop.h only where it's needed. Touching it now recompiles only some 1700 objects. For block/aio.h and qemu/event_notifier.h, these numbers drop from 5600 to 2800. For the others, they shrink only slightly. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190812052359.30071-21-armbru@redhat.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
* Include hw/hw.h exactly where neededMarkus Armbruster2019-08-161-1/+0Star
| | | | | | | | | | | | | | | | In my "build everything" tree, changing hw/hw.h triggers a recompile of some 2600 out of 6600 objects (not counting tests and objects that don't depend on qemu/osdep.h). The previous commits have left only the declaration of hw_error() in hw/hw.h. This permits dropping most of its inclusions. Touching it now recompiles less than 200 objects. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20190812052359.30071-19-armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
* xen: Import other xen/io/*.hAnthony PERARD2019-06-241-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | A Xen public header have been imported into QEMU (by f65eadb639 "xen: import ring.h from xen"), but there are other header that depends on ring.h which come from the system when building QEMU. This patch resolves the issue of having headers from the system importing a different copie of ring.h. This patch is prompt by the build issue described in the previous patch: 'Revert xen/io/ring.h of "Clean up a few header guard symbols"' ring.h and the new imported headers are moved to "include/hw/xen/interface" as those describe interfaces with a guest. The imported headers are cleaned up a bit while importing them: some part of the file that QEMU doesn't use are removed (description of how to make hypercall in grant_table.h have been removed). Other cleanup: - xen-mapcache.c and xen-legacy-backend.c don't need grant_table.h. - xenfb.c doesn't need event_channel.h. Signed-off-by: Anthony PERARD <anthony.perard@citrix.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com> Message-Id: <20190621105441.3025-3-anthony.perard@citrix.com>
* Supply missing header guardsMarkus Armbruster2019-06-121-1/+5
| | | | | Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190604181618.19980-5-armbru@redhat.com>
* Include qemu-common.h exactly where neededMarkus Armbruster2019-06-122-1/+1
| | | | | | | | | | | | | | | | No header includes qemu-common.h after this commit, as prescribed by qemu-common.h's file comment. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-5-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and net/tap-bsd.c fixed up]
* Include qemu/module.h where needed, drop it from qemu-common.hMarkus Armbruster2019-06-121-0/+1
| | | | | | | | | Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-4-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for hw/usb/dev-hub.c hw/misc/exynos4210_rng.c hw/misc/bcm2835_rng.c hw/misc/aspeed_scu.c hw/display/virtio-vga.c hw/arm/stm32f205_soc.c; ui/cocoa.m fixed up]
* trace-events: Fix attribution of trace points to sourceMarkus Armbruster2019-03-221-1/+1
| | | | | | | | | | | | | | | Some trace points are attributed to the wrong source file. Happens when we neglect to update trace-events for code motion, or add events in the wrong place, or misspell the file name. Clean up with help of cleanup-trace-events.pl. Same funnies as in the previous commit, of course. Manually shorten its change to linux-user/trace-events to */signal.c. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-id: 20190314180929.27722-6-armbru@redhat.com Message-Id: <20190314180929.27722-6-armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* trace-events: Shorten file names in commentsMarkus Armbruster2019-03-221-1/+1
| | | | | | | | | | | | | | | We spell out sub/dir/ in sub/dir/trace-events' comments pointing to source files. That's because when trace-events got split up, the comments were moved verbatim. Delete the sub/dir/ part from these comments. Gets rid of several misspellings. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-id: 20190314180929.27722-3-armbru@redhat.com Message-Id: <20190314180929.27722-3-armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* virtio: express virtio dependencies with KconfigYang Zhong2019-03-071-1/+1
| | | | | | | Signed-off-by: Yang Zhong <yang.zhong@intel.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Message-Id: <20190123065618.3520-42-yang.zhong@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* build: switch to KconfigPaolo Bonzini2019-03-071-0/+2
| | | | | | | | | | | | | | | | | | | | The make_device_config.sh script is replaced by minikconf, which is modified to support the same command line as its predecessor. The roots of the parsing are default-configs/*.mak, Kconfig.host and hw/Kconfig. One difference with make_device_config.sh is that all symbols have to be defined in a Kconfig file, including those coming from the configure script. This is the reason for the Kconfig.host file introduced in the previous patch. Whenever a file in default-configs/*.mak used $(...) to refer to a config-host.mak symbol, this is replaced by a Kconfig dependency; this part must be done already in this patch for bisectability. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Yang Zhong <yang.zhong@intel.com> Acked-by: Thomas Huth <thuth@redhat.com> Message-Id: <20190123065618.3520-28-yang.zhong@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kconfig: introduce kconfig filesPaolo Bonzini2019-03-071-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Kconfig files were generated mostly with this script: for i in `grep -ho CONFIG_[A-Z0-9_]* default-configs/* | sort -u`; do set fnord `git grep -lw $i -- 'hw/*/Makefile.objs' ` shift if test $# = 1; then cat >> $(dirname $1)/Kconfig << EOF config ${i#CONFIG_} bool EOF git add $(dirname $1)/Kconfig else echo $i $* fi done sed -i '$d' hw/*/Kconfig for i in hw/*; do if test -d $i && ! test -f $i/Kconfig; then touch $i/Kconfig git add $i/Kconfig fi done Whenever a symbol is referenced from multiple subdirectories, the script prints the list of directories that reference the symbol. These symbols have to be added manually to the Kconfig files. Kconfig.host and hw/Kconfig were created manually. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Yang Zhong <yang.zhong@intel.com> Message-Id: <20190123065618.3520-27-yang.zhong@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* 9pfs: remove unnecessary conditionalsPaolo Bonzini2019-03-071-2/+0Star
| | | | | | | The VIRTIO_9P || VIRTFS && XEN condition can be computed in hw/Makefile.objs, removing an "if" from hw/9pfs/Makefile.objs. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* xen: re-name XenDevice to XenLegacyDevice...Paul Durrant2019-01-141-8/+8
| | | | | | | | | | | | | | | | | ...and xen_backend.h to xen-legacy-backend.h Rather than attempting to convert the existing backend infrastructure to be QOM compliant (which would be hard to do in an incremental fashion), subsequent patches will introduce a completely new framework for Xen PV backends. Hence it is necessary to re-name parts of existing code to avoid name clashes. The re-named 'legacy' infrastructure will be removed once all backends have been ported to the new framework. This patch is purely cosmetic. No functional change. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
* 9p: remove support for the "handle" backendGreg Kurz2018-12-122-711/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The "handle" fsdev backend was deprecated in QEMU 2.12.0 with: commit db3b3c7281ca82e2647e072a1f97db111313dd73 Author: Greg Kurz <groug@kaod.org> Date: Mon Jan 8 11:18:23 2018 +0100 9pfs: deprecate handle backend This backend raise some concerns: - doesn't support symlinks - fails +100 tests in the PJD POSIX file system test suite [1] - requires the QEMU process to run with the CAP_DAC_READ_SEARCH capability, which isn't recommended for security reasons This backend should not be used and wil be removed. The 'local' backend is the recommended alternative. [1] https://www.tuxera.com/community/posix-test-suite/ Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> It has passed the two release cooling period without any complaint. Remove it now. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Thomas Huth <thuth@redhat.com>
* xen/9pfs: use g_new(T, n) instead of g_malloc(sizeof(T) * n)Greg Kurz2018-12-121-3/+3
| | | | | | | Because it is a recommended coding practice (see HACKING). Signed-off-by: Greg Kurz <groug@kaod.org> Acked-by: Anthony PERARD <anthony.perard@citrix.com>
* 9p: use g_new(T, n) instead of g_malloc(sizeof(T) * n)Greg Kurz2018-12-121-2/+2
| | | | | | | Because it is a recommended coding practice (see HACKING). Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
* 9p: fix QEMU crash when renaming filesGreg Kurz2018-11-231-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When using the 9P2000.u version of the protocol, the following shell command line in the guest can cause QEMU to crash: while true; do rm -rf aa; mkdir -p a/b & touch a/b/c & mv a aa; done With 9P2000.u, file renaming is handled by the WSTAT command. The v9fs_wstat() function calls v9fs_complete_rename(), which calls v9fs_fix_path() for every fid whose path is affected by the change. The involved calls to v9fs_path_copy() may race with any other access to the fid path performed by some worker thread, causing a crash like shown below: Thread 12 "qemu-system-x86" received signal SIGSEGV, Segmentation fault. 0x0000555555a25da2 in local_open_nofollow (fs_ctx=0x555557d958b8, path=0x0, flags=65536, mode=0) at hw/9pfs/9p-local.c:59 59 while (*path && fd != -1) { (gdb) bt #0 0x0000555555a25da2 in local_open_nofollow (fs_ctx=0x555557d958b8, path=0x0, flags=65536, mode=0) at hw/9pfs/9p-local.c:59 #1 0x0000555555a25e0c in local_opendir_nofollow (fs_ctx=0x555557d958b8, path=0x0) at hw/9pfs/9p-local.c:92 #2 0x0000555555a261b8 in local_lstat (fs_ctx=0x555557d958b8, fs_path=0x555556b56858, stbuf=0x7fff84830ef0) at hw/9pfs/9p-local.c:185 #3 0x0000555555a2b367 in v9fs_co_lstat (pdu=0x555557d97498, path=0x555556b56858, stbuf=0x7fff84830ef0) at hw/9pfs/cofile.c:53 #4 0x0000555555a1e9e2 in v9fs_stat (opaque=0x555557d97498) at hw/9pfs/9p.c:1083 #5 0x0000555555e060a2 in coroutine_trampoline (i0=-669165424, i1=32767) at util/coroutine-ucontext.c:116 #6 0x00007fffef4f5600 in __start_context () at /lib64/libc.so.6 #7 0x0000000000000000 in () (gdb) The fix is to take the path write lock when calling v9fs_complete_rename(), like in v9fs_rename(). Impact: DoS triggered by unprivileged guest users. Fixes: CVE-2018-19489 Cc: P J P <ppandit@redhat.com> Reported-by: zhibin hu <noirfate@gmail.com> Reviewed-by: Prasad J Pandit <pjp@fedoraproject.org> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: take write lock on fid path updates (CVE-2018-19364)Greg Kurz2018-11-201-0/+15
| | | | | | | | | | | | | | | | | | Recent commit 5b76ef50f62079a fixed a race where v9fs_co_open2() could possibly overwrite a fid path with v9fs_path_copy() while it is being accessed by some other thread, ie, use-after-free that can be detected by ASAN with a custom 9p client. It turns out that the same can happen at several locations where v9fs_path_copy() is used to set the fid path. The fix is again to take the write lock. Fixes CVE-2018-19364. Cc: P J P <ppandit@redhat.com> Reported-by: zhibin hu <noirfate@gmail.com> Reviewed-by: Prasad J Pandit <pjp@fedoraproject.org> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: write lock path in v9fs_co_open2()Greg Kurz2018-11-081-3/+3
| | | | | | | | | | | | | | | | | | The assumption that the fid cannot be used by any other operation is wrong. At least, nothing prevents a misbehaving client to create a file with a given fid, and to pass this fid to some other operation at the same time (ie, without waiting for the response to the creation request). The call to v9fs_path_copy() performed by the worker thread after the file was created can race with any access to the fid path performed by some other thread. This causes use-after-free issues that can be detected by ASAN with a custom 9p client. Unlike other operations that only read the fid path, v9fs_co_open2() does modify it. It should hence take the write lock. Cc: P J P <ppandit@redhat.com> Reported-by: zhibin hu <noirfate@gmail.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* fsdev: Clean up error reporting in qemu_fsdev_add()Markus Armbruster2018-10-191-1/+6
| | | | | | | | | | | | | Calling error_report() from within a function that takes an Error ** argument is suspicious. qemu_fsdev_add() does that, and its caller fsdev_init_func() then fails without setting an error. Its caller main(), via qemu_opts_foreach(), is fine with it, but clean it up anyway. Cc: Greg Kurz <groug@kaod.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Acked-by: Greg Kurz <groug@kaod.org> Message-Id: <20181017082702.5581-32-armbru@redhat.com>
* 9pfs: Fix CLI parsing crash on errorMarkus Armbruster2018-10-191-2/+4
| | | | | | | | | | | | | | | | | | | | | | Calling error_report() in a function that takes an Error ** argument is suspicious. 9p-handle.c's handle_parse_opts() does that, and then fails without setting an error. Wrong. Its caller crashes when it tries to report the error: $ qemu-system-x86_64 -nodefaults -fsdev id=foo,fsdriver=handle qemu-system-x86_64: -fsdev id=foo,fsdriver=handle: warning: handle backend is deprecated qemu-system-x86_64: -fsdev id=foo,fsdriver=handle: fsdev: No path specified Segmentation fault (core dumped) Screwed up when commit 91cda4e8f37 (v2.12.0) converted the function to Error. Fix by calling error_setg() instead of error_report(). Fixes: 91cda4e8f372602795e3a2f4bd2e3adaf9f82255 Cc: Greg Kurz <groug@kaod.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Acked-by: Greg Kurz <groug@kaod.org> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20181017082702.5581-9-armbru@redhat.com>
* error: Fix use of error_prepend() with &error_fatal, &error_abortMarkus Armbruster2018-10-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | From include/qapi/error.h: * Pass an existing error to the caller with the message modified: * error_propagate(errp, err); * error_prepend(errp, "Could not frobnicate '%s': ", name); Fei Li pointed out that doing error_propagate() first doesn't work well when @errp is &error_fatal or &error_abort: the error_prepend() is never reached. Since I doubt fixing the documentation will stop people from getting it wrong, introduce error_propagate_prepend(), in the hope that it lures people away from using its constituents in the wrong order. Update the instructions in error.h accordingly. Convert existing error_prepend() next to error_propagate to error_propagate_prepend(). If any of these get reached with &error_fatal or &error_abort, the error messages improve. I didn't check whether that's the case anywhere. Cc: Fei Li <fli@suse.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20181017082702.5581-2-armbru@redhat.com>
* 9p: darwin: Explicitly cast comparisons of mode_t with -1Keno Fischer2018-06-291-2/+2
| | | | | | | | Comparisons of mode_t with -1 require an explicit cast, since mode_t is unsigned on Darwin. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* cutils: Provide strchrnulKeno Fischer2018-06-291-1/+1
| | | | | | | | | | | | | strchrnul is a GNU extension and thus unavailable on a number of targets. In the review for a commit removing strchrnul from 9p, I was asked to create a qemu_strchrnul helper to factor out this functionality. Do so, and use it in a number of other places in the code base that inlined the replacement pattern in a place where strchrnul could be used. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Acked-by: Greg Kurz <groug@kaod.org> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: xattr: Properly translate xattrcreate flagsKeno Fischer2018-06-072-2/+19
| | | | | | | | | As with unlinkat, these flags come from the client and need to be translated to their host values. The protocol values happen to match linux, but that need not be true in general. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: Properly check/translate flags in unlinkatKeno Fischer2018-06-072-9/+12
| | | | | | | | | | | | The 9p-local code previously relied on P9_DOTL_AT_REMOVEDIR and AT_REMOVEDIR having the same numerical value and deferred any errorchecking to the syscall itself. However, while the former assumption is true on Linux, it is not true in general. 9p-handle did this properly however. Move the translation code to the generic 9p server code and add an error if unrecognized flags are passed. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: local: Avoid warning if FS_IOC_GETVERSION is not definedKeno Fischer2018-06-071-17/+23
| | | | | | | | | | Both `stbuf` and `local_ioc_getversion` where unused when FS_IOC_GETVERSION was not defined, causing a compiler warning. Reorganize the code to avoid this warning. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: xattr: Fix crashes due to free of uninitialized valueKeno Fischer2018-06-071-2/+2
| | | | | | | | | | | If the size returned from llistxattr/lgetxattr is 0, we skipped the malloc call, leaving xattr.value uninitialized. However, this value is later passed to `g_free` without any further checks, causing an error. Fix that by always calling g_malloc unconditionally. If `size` is 0, it will return NULL, which is safe to pass to g_free. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: Move a couple xattr functions to 9p-utilKeno Fischer2018-06-073-33/+37
| | | | | | | | | These functions will need custom implementations on Darwin. Since the implementation is very similar among all of them, and 9p-util already has the _nofollow version of fgetxattrat, let's move them all there. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: local: Properly set errp in fstatfs error pathKeno Fischer2018-06-071-0/+2
| | | | | | | | | | | | | In the review of 9p: Avoid warning if FS_IOC_GETVERSION is not defined Grep Kurz noted this error path was failing to set errp. Fix that. Signed-off-by: Keno Fischer <keno@juliacomputing.com> [added local: to commit title, Greg Kurz] Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: proxy: Fix size passed to `connect`Keno Fischer2018-06-071-3/+2Star
| | | | | | | | | The size to pass to the `connect` call is the size of the entire `struct sockaddr_un`. Passing anything shorter than this causes errors on darwin. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* hw: make virtio devices configurable via default-configs/Paolo Bonzini2018-06-011-2/+4
| | | | | | | | | This is only half of the work, because the proxy devices (virtio-*-pci, virtio-*-ccw, etc.) are still included unconditionally. It is still a move in the right direction. Based-on: <20180522194943.24871-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* xen: remove other open-coded use of libxengnttabPaul Durrant2018-05-221-17/+15Star
| | | | | | | | | Now that helpers are available in xen_backend, use them throughout all Xen PV backends. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
* 9p: add trace event for v9fs_setattr()Greg Kurz2018-05-022-0/+7
| | | | | | | | Don't print the tv_nsec part of atime and mtime, to stay below the 10 argument limit of trace events. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
* 9p: fix leak in synth_name_to_path()Marc-André Lureau2018-02-191-0/+1
| | | | | | | | | | | | | | Leak found thanks to ASAN: Direct leak of 8 byte(s) in 1 object(s) allocated from: #0 0x55995789ac90 in __interceptor_malloc (/home/elmarco/src/qemu/build/x86_64-softmmu/qemu-system-x86_64+0x1510c90) #1 0x7f0a91190f0c in g_malloc /home/elmarco/src/gnome/glib/builddir/../glib/gmem.c:94 #2 0x5599580a281c in v9fs_path_copy /home/elmarco/src/qemu/hw/9pfs/9p.c:196:17 #3 0x559958f9ec5d in coroutine_trampoline /home/elmarco/src/qemu/util/coroutine-ucontext.c:116:9 #4 0x7f0a8766ebbf (/lib64/libc.so.6+0x50bbf) Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* 9p: v9fs_path_copy() readabilityMarc-André Lureau2018-02-192-6/+5Star
| | | | | | | | lhs/rhs doesn't tell much about how argument are handled, dst/src is and const arguments is clearer in my mind. Use g_memdup() while at it. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Greg Kurz <groug@kaod.org>
* Move include qemu/option.h from qemu-common.h to actual usersMarkus Armbruster2018-02-094-0/+4
| | | | | | | | | | | | | | | | | | qemu-common.h includes qemu/option.h, but most places that include the former don't actually need the latter. Drop the include, and add it to the places that actually need it. While there, drop superfluous includes of both headers, and separate #include from file comment with a blank line. This cleanup makes the number of objects depending on qemu/option.h drop from 4545 (out of 4743) to 284 in my "build everything" tree. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180201111846.21846-20-armbru@redhat.com> [Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
* Include qapi/error.h exactly where neededMarkus Armbruster2018-02-092-1/+3
| | | | | | | | | | | | | | This cleanup makes the number of objects depending on qapi/error.h drop from 1910 (out of 4743) to 1612 in my "build everything" tree. While there, separate #include from file comment with a blank line, and drop a useless comment on why qemu/osdep.h is included first. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180201111846.21846-5-armbru@redhat.com> [Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
* tests: virtio-9p: add FLUSH operation testGreg Kurz2018-02-023-0/+28
| | | | | | | | | | | | | | | | | | | | The idea is to send a victim request that will possibly block in the server and to send a flush request to cancel the victim request. This patch adds two test to verifiy that: - the server does not reply to a victim request that was actually cancelled - the server replies to the flush request after replying to the victim request if it could not cancel it 9p request cancellation reference: http://man.cat-v.org/plan_9/5/flush Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> (groug, change the test to only write a single byte to avoid any alignment or endianess consideration)
* tests: virtio-9p: add WRITE operation testGreg Kurz2018-02-012-0/+12
| | | | | | | | | | | Trivial test of a successful write. Signed-off-by: Greg Kurz <groug@kaod.org> (groug, handle potential overflow when computing request size, add missing g_free(buf), backend handles one written byte at a time to validate the server doesn't do short-reads) Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>