- Linux-stable-mirror - lists.linaro.org

[Linux-stable-mirror] Applied "regmap: Fix reversed bounds check in regmap_raw_write()" to the regmap tree

by Mark Brown

The patch regmap: Fix reversed bounds check in regmap_raw_write() has been applied to the regmap tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From f00e71091ab92eba52122332586c6ecaa9cd1a56 Mon Sep 17 00:00:00 2001 From: Dan Carpenter <dan.carpenter(a)oracle.com> Date: Thu, 8 Feb 2018 10:23:44 +0300 Subject: [PATCH] regmap: Fix reversed bounds check in regmap_raw_write() We're supposed to be checking that "val_len" is not too large but instead we check if it is smaller than the max. The only function affected would be regmap_i2c_smbus_i2c_write() in drivers/base/regmap/regmap-i2c.c. Strangely that function has its own limit check which returns an error if (count >= I2C_SMBUS_BLOCK_MAX) so it doesn't look like it has ever been able to do anything except return an error. Fixes: c335931ed9d2 ("regmap: Add raw_write/read checks for max_raw_write/read sizes") Signed-off-by: Dan Carpenter <dan.carpenter(a)oracle.com> Signed-off-by: Mark Brown <broonie(a)kernel.org> Cc: stable(a)vger.kernel.org --- drivers/base/regmap/regmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index ee302ccdfbc8..453116fd4362 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -1831,7 +1831,7 @@ int regmap_raw_write(struct regmap *map, unsigned int reg, return -EINVAL; if (val_len % map->format.val_bytes) return -EINVAL; - if (map->max_raw_write && map->max_raw_write > val_len) + if (map->max_raw_write && map->max_raw_write < val_len) return -E2BIG; map->lock(map->lock_arg); -- 2.15.1

7 years, 10 months

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[Linux-stable-mirror] [PATCH v3] xenbus: track caller request id

by Joao Martins

Commit fd8aa9095a95 ("xen: optimize xenbus driver for multiple concurrent xenstore accesses") optimized xenbus concurrent accesses but in doing so broke UABI of /dev/xen/xenbus. Through /dev/xen/xenbus applications are in charge of xenbus message exchange with the correct header and body. Now, after the mentioned commit the replies received by application will no longer have the header req_id echoed back as it was on request (see specification below for reference), because that particular field is being overwritten by kernel. struct xsd_sockmsg { uint32_t type; /* XS_??? */ uint32_t req_id;/* Request identifier, echoed in daemon's response. */ uint32_t tx_id; /* Transaction id (0 if not related to a transaction). */ uint32_t len; /* Length of data following this. */ /* Generally followed by nul-terminated string(s). */ }; Before there was only one request at a time so req_id could simply be forwarded back and forth. To allow simultaneous requests we need a different req_id for each message thus kernel keeps a monotonic increasing counter for this field and is written on every request irrespective of userspace value. Forwarding again the req_id on userspace requests is not a solution because we would open the possibility of userspace-generated req_id colliding with kernel ones. So this patch instead takes another route which is to artificially keep user req_id while keeping the xenbus logic as is. We do that by saving the original req_id before xs_send(), use the private kernel counter as req_id and then once reply comes and was validated, we restore back the original req_id. Cc: <stable(a)vger.kernel.org> # 4.11 Fixes: fd8aa9095a ("xen: optimize xenbus driver for multiple concurrent xenstore accesses") Reported-by: Bhavesh Davda <bhavesh.davda(a)oracle.com> Signed-off-by: Joao Martins <joao.m.martins(a)oracle.com> Reviewed-by: Juergen Gross <jgross(a)suse.com> --- Here's a link to a unit test (https://pastebin.com/N0kqNBnM) where req_id of reply and response are being asserted each request. Without this patch the assert will fail (e.g. try it with `./xswire_reqid_test name`). But on <= v4.10 or >= v4.11 with the fix above, it will print domain name 10 times. Changes since v2: * Add Juergen's Reviewed-by Changes since v1: * Adjust commit message (Comments from Juergen on IRC) * Unilateraly save/restore req_id and remove xs_request_is_user() * Initialize req_id for kernel callers --- drivers/xen/xenbus/xenbus.h | 1 + drivers/xen/xenbus/xenbus_comms.c | 1 + drivers/xen/xenbus/xenbus_xs.c | 3 +++ 3 files changed, 5 insertions(+) diff --git a/drivers/xen/xenbus/xenbus.h b/drivers/xen/xenbus/xenbus.h index 149c5e7efc89..092981171df1 100644 --- a/drivers/xen/xenbus/xenbus.h +++ b/drivers/xen/xenbus/xenbus.h @@ -76,6 +76,7 @@ struct xb_req_data { struct list_head list; wait_queue_head_t wq; struct xsd_sockmsg msg; + uint32_t caller_req_id; enum xsd_sockmsg_type type; char *body; const struct kvec *vec; diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c index 5b081a01779d..d239fc3c5e3d 100644 --- a/drivers/xen/xenbus/xenbus_comms.c +++ b/drivers/xen/xenbus/xenbus_comms.c @@ -309,6 +309,7 @@ static int process_msg(void) goto out; if (req->state == xb_req_state_wait_reply) { + req->msg.req_id = req->caller_req_id; req->msg.type = state.msg.type; req->msg.len = state.msg.len; req->body = state.body; diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c index 3e59590c7254..3f3b29398ab8 100644 --- a/drivers/xen/xenbus/xenbus_xs.c +++ b/drivers/xen/xenbus/xenbus_xs.c @@ -227,6 +227,8 @@ static void xs_send(struct xb_req_data *req, struct xsd_sockmsg *msg) req->state = xb_req_state_queued; init_waitqueue_head(&req->wq); + /* Save the caller req_id and restore it later in the reply */ + req->caller_req_id = req->msg.req_id; req->msg.req_id = xs_request_enter(req); mutex_lock(&xb_write_mutex); @@ -310,6 +312,7 @@ static void *xs_talkv(struct xenbus_transaction t, req->num_vecs = num_vecs; req->cb = xs_wake_up; + msg.req_id = 0; msg.tx_id = t.id; msg.type = type; msg.len = 0; -- 2.11.0

7 years, 10 months

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[Linux-stable-mirror] [RFC][PATCH 2/6] tracing: Fix parsing of globs with a wildcard at the beginning

by Steven Rostedt

From: "Steven Rostedt (VMware)" <rostedt(a)goodmis.org> Al Viro reported: For substring - sure, but what about something like "*a*b" and "a*b"? AFAICS, filter_parse_regex() ends up with identical results in both cases - MATCH_GLOB and *search = "a*b". And no way for the caller to tell one from another. Testing this with the following: # cd /sys/kernel/tracing # echo '*raw*lock' > set_ftrace_filter bash: echo: write error: Invalid argument With this patch: # echo '*raw*lock' > set_ftrace_filter # cat set_ftrace_filter _raw_read_trylock _raw_write_trylock _raw_read_unlock _raw_spin_unlock _raw_write_unlock _raw_spin_trylock _raw_spin_lock _raw_write_lock _raw_read_lock Al recommended not setting the search buffer to skip the first '*' unless we know we are not using MATCH_GLOB. This implements his suggested logic. Link: http://lkml.kernel.org/r/20180127170748.GF13338@ZenIV.linux.org.uk Cc: stable(a)vger.kernel.org Cc: Masami Hiramatsu <mhiramat(a)kernel.org> Fixes: 60f1d5e3bac44 ("ftrace: Support full glob matching") Reported-by: Al Viro <viro(a)ZenIV.linux.org.uk> Suggsted-by: Al Viro <viro(a)ZenIV.linux.org.uk> Signed-off-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org> --- kernel/trace/trace_events_filter.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 61e7f0678d33..a764aec3c9a1 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -400,7 +400,6 @@ enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not) for (i = 0; i < len; i++) { if (buff[i] == '*') { if (!i) { - *search = buff + 1; type = MATCH_END_ONLY; } else if (i == len - 1) { if (type == MATCH_END_ONLY) @@ -410,14 +409,14 @@ enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not) buff[i] = 0; break; } else { /* pattern continues, use full glob */ - type = MATCH_GLOB; - break; + return MATCH_GLOB; } } else if (strchr("[?\\", buff[i])) { - type = MATCH_GLOB; - break; + return MATCH_GLOB; } } + if (buff[0] == '*') + *search = buff + 1; return type; } -- 2.15.1

7 years, 10 months

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[Linux-stable-mirror] [RFC][PATCH 1/6] ftrace: Remove incorrect setting of glob search field

by Steven Rostedt

From: "Steven Rostedt (VMware)" <rostedt(a)goodmis.org> __unregister_ftrace_function_probe() will incorrectly parse the glob filter because it resets the search variable that was setup by filter_parse_regex(). Al Viro reported this: After that call of filter_parse_regex() we could have func_g.search not equal to glob only if glob started with '!' or '*'. In the former case we would've buggered off with -EINVAL (not = 1). In the latter we would've set func_g.search equal to glob + 1, calculated the length of that thing in func_g.len and proceeded to reset func_g.search back to glob. Suppose the glob is e.g. *foo*. We end up with func_g.type = MATCH_MIDDLE_ONLY; func_g.len = 3; func_g.search = "*foo"; Feeding that to ftrace_match_record() will not do anything sane - we will be looking for names containing "*foo" (->len is ignored for that one). Link: http://lkml.kernel.org/r/20180127031706.GE13338@ZenIV.linux.org.uk Cc: stable(a)vger.kernel.org Cc: Dmitry Safonov <0x7f454c46(a)gmail.com> Fixes: 3ba009297149f ("ftrace: Introduce ftrace_glob structure") Reported-by: Al Viro <viro(a)ZenIV.linux.org.uk> Signed-off-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org> --- kernel/trace/ftrace.c | 1 - 1 file changed, 1 deletion(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index dabd9d167d42..eac9ce2c57a2 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -4456,7 +4456,6 @@ unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, func_g.type = filter_parse_regex(glob, strlen(glob), &func_g.search, &not); func_g.len = strlen(func_g.search); - func_g.search = glob; /* we do not support '!' for function probes */ if (WARN_ON(not)) -- 2.15.1

7 years, 10 months

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[Linux-stable-mirror] [PATCH] xen: Fix {set, clear}_foreign_p2m_mapping on autotranslating guests

by Simon Gaiser

Commit 82616f9599a7 ("xen: remove tests for pvh mode in pure pv paths") removed the check for autotranslation from {set,clear}_foreign_p2m_mapping but those are called by grant-table.c also on PVH/HVM guests. Cc: <stable(a)vger.kernel.org> # 4.14 Fixes: 82616f9599a7 ("xen: remove tests for pvh mode in pure pv paths") Signed-off-by: Simon Gaiser <simon(a)invisiblethingslab.com> Reviewed-by: Juergen Gross <jgross(a)suse.com> --- arch/x86/xen/p2m.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 13b4f19b9131..159a897151d6 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -694,6 +694,9 @@ int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, int i, ret = 0; pte_t *pte; + if (xen_feature(XENFEAT_auto_translated_physmap)) + return 0; + if (kmap_ops) { ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, kmap_ops, count); @@ -736,6 +739,9 @@ int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, { int i, ret = 0; + if (xen_feature(XENFEAT_auto_translated_physmap)) + return 0; + for (i = 0; i < count; i++) { unsigned long mfn = __pfn_to_mfn(page_to_pfn(pages[i])); unsigned long pfn = page_to_pfn(pages[i]); -- 2.15.1

7 years, 10 months

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[Linux-stable-mirror] [PATCH 1/7] media: v4l2-compat-ioctl32.c: make ctrl_is_pointer work for subdevs

by Hans Verkuil

From: Hans Verkuil <hansverk(a)cisco.com> If the device is of type VFL_TYPE_SUBDEV then vdev->ioctl_ops is NULL so the 'if (!ops->vidioc_query_ext_ctrl)' check would crash. Add a test for !ops to the condition. All sub-devices that have controls will use the control framework, so they do not have an equivalent to ops->vidioc_query_ext_ctrl. Returning false if ops is NULL is the correct thing to do here. Fixes: b8c601e8af ("v4l2-compat-ioctl32.c: fix ctrl_is_pointer") Signed-off-by: Hans Verkuil <hans.verkuil(a)cisco.com> Acked-by: Sakari Ailus <sakari.ailus(a)linux.intel.com> Reported-by: Laurent Pinchart <laurent.pinchart(a)ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart(a)ideasonboard.com> Cc: <stable(a)vger.kernel.org> # for v4.15 and up Signed-off-by: Mauro Carvalho Chehab <mchehab(a)s-opensource.com> --- drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c index bdb5c226d01c..5198c9eeb348 100644 --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c @@ -770,7 +770,7 @@ static inline bool ctrl_is_pointer(struct file *file, u32 id) return ctrl && ctrl->is_ptr; } - if (!ops->vidioc_query_ext_ctrl) + if (!ops || !ops->vidioc_query_ext_ctrl) return false; return !ops->vidioc_query_ext_ctrl(file, fh, &qec) && -- 2.15.1

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[Linux-stable-mirror] v4.15.2 build: 0 failures 0 warnings (v4.15.2)

by Build bot for Mark Brown

Tree/Branch: v4.15.2 Git describe: v4.15.2 Commit: db22ec452b Linux 4.15.2 Build Time: 112 min 8 sec Passed: 10 / 10 (100.00 %) Failed: 0 / 10 ( 0.00 %) Errors: 0 Warnings: 0 Section Mismatches: 0 ------------------------------------------------------------------------------- defconfigs with issues (other than build errors): ------------------------------------------------------------------------------- =============================================================================== Detailed per-defconfig build reports below: ------------------------------------------------------------------------------- Passed with no errors, warnings or mismatches: arm64-allnoconfig arm64-allmodconfig arm-multi_v5_defconfig arm-multi_v7_defconfig x86_64-defconfig arm-allmodconfig arm-allnoconfig x86_64-allnoconfig arm-multi_v4t_defconfig arm64-defconfig close failed in file object destructor: sys.excepthook is missing lost sys.stderr

7 years, 10 months

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[Linux-stable-mirror] v4.14.18 build: 0 failures 0 warnings (v4.14.18)

by Build bot for Mark Brown

Tree/Branch: v4.14.18 Git describe: v4.14.18 Commit: 81d0cc85ca Linux 4.14.18 Build Time: 108 min 51 sec Passed: 10 / 10 (100.00 %) Failed: 0 / 10 ( 0.00 %) Errors: 0 Warnings: 0 Section Mismatches: 0 ------------------------------------------------------------------------------- defconfigs with issues (other than build errors): ------------------------------------------------------------------------------- =============================================================================== Detailed per-defconfig build reports below: ------------------------------------------------------------------------------- Passed with no errors, warnings or mismatches: arm64-allnoconfig arm64-allmodconfig arm-multi_v5_defconfig arm-multi_v7_defconfig x86_64-defconfig arm-allmodconfig arm-allnoconfig x86_64-allnoconfig arm-multi_v4t_defconfig arm64-defconfig close failed in file object destructor: sys.excepthook is missing lost sys.stderr

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[Linux-stable-mirror] Patch "x86/usercopy: Replace open coded stac/clac with __uaccess_{begin, end}" has been added to the 4.9-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled x86/usercopy: Replace open coded stac/clac with __uaccess_{begin, end} to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: x86-usercopy-replace-open-coded-stac-clac-with-__uaccess_-begin-end.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From foo@baz Thu Feb 8 03:32:24 CET 2018 From: Dan Williams <dan.j.williams(a)intel.com> Date: Mon, 29 Jan 2018 17:02:44 -0800 Subject: x86/usercopy: Replace open coded stac/clac with __uaccess_{begin, end} From: Dan Williams <dan.j.williams(a)intel.com> (cherry picked from commit b5c4ae4f35325d520b230bab6eb3310613b72ac1) In preparation for converting some __uaccess_begin() instances to __uacess_begin_nospec(), make sure all 'from user' uaccess paths are using the _begin(), _end() helpers rather than open-coded stac() and clac(). No functional changes. Suggested-by: Ingo Molnar <mingo(a)redhat.com> Signed-off-by: Dan Williams <dan.j.williams(a)intel.com> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Cc: linux-arch(a)vger.kernel.org Cc: Tom Lendacky <thomas.lendacky(a)amd.com> Cc: Kees Cook <keescook(a)chromium.org> Cc: kernel-hardening(a)lists.openwall.com Cc: gregkh(a)linuxfoundation.org Cc: Al Viro <viro(a)zeniv.linux.org.uk> Cc: torvalds(a)linux-foundation.org Cc: alan(a)linux.intel.com Link: https://lkml.kernel.org/r/151727416438.33451.17309465232057176966.stgit@dwi… Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- arch/x86/lib/usercopy_32.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/x86/lib/usercopy_32.c +++ b/arch/x86/lib/usercopy_32.c @@ -570,12 +570,12 @@ do { \ unsigned long __copy_to_user_ll(void __user *to, const void *from, unsigned long n) { - stac(); + __uaccess_begin(); if (movsl_is_ok(to, from, n)) __copy_user(to, from, n); else n = __copy_user_intel(to, from, n); - clac(); + __uaccess_end(); return n; } EXPORT_SYMBOL(__copy_to_user_ll); @@ -627,7 +627,7 @@ EXPORT_SYMBOL(__copy_from_user_ll_nocach unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from, unsigned long n) { - stac(); + __uaccess_begin(); #ifdef CONFIG_X86_INTEL_USERCOPY if (n > 64 && static_cpu_has(X86_FEATURE_XMM2)) n = __copy_user_intel_nocache(to, from, n); @@ -636,7 +636,7 @@ unsigned long __copy_from_user_ll_nocach #else __copy_user(to, from, n); #endif - clac(); + __uaccess_end(); return n; } EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero); Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are queue-4.9/kvm-vmx-allow-direct-access-to-msr_ia32_spec_ctrl.patch queue-4.9/kvm-x86-add-ibpb-support.patch queue-4.9/kvm-svm-allow-direct-access-to-msr_ia32_spec_ctrl.patch queue-4.9/x86-paravirt-remove-noreplace-paravirt-cmdline-option.patch queue-4.9/documentation-document-array_index_nospec.patch queue-4.9/x86-usercopy-replace-open-coded-stac-clac-with-__uaccess_-begin-end.patch queue-4.9/kvm-x86-make-indirect-calls-in-emulator-speculation-safe.patch queue-4.9/vfs-fdtable-prevent-bounds-check-bypass-via-speculative-execution.patch queue-4.9/x86-uaccess-use-__uaccess_begin_nospec-and-uaccess_try_nospec.patch queue-4.9/x86-implement-array_index_mask_nospec.patch queue-4.9/array_index_nospec-sanitize-speculative-array-de-references.patch queue-4.9/kvm-vmx-make-indirect-call-speculation-safe.patch queue-4.9/x86-kvm-update-spectre-v1-mitigation.patch queue-4.9/x86-get_user-use-pointer-masking-to-limit-speculation.patch queue-4.9/x86-syscall-sanitize-syscall-table-de-references-under-speculation.patch queue-4.9/x86-spectre-report-get_user-mitigation-for-spectre_v1.patch queue-4.9/x86-introduce-barrier_nospec.patch queue-4.9/kvm-vmx-emulate-msr_ia32_arch_capabilities.patch queue-4.9/x86-introduce-__uaccess_begin_nospec-and-uaccess_try_nospec.patch queue-4.9/nl80211-sanitize-array-index-in-parse_txq_params.patch

7 years, 10 months

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[Linux-stable-mirror] Patch "x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec" has been added to the 4.9-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: x86-uaccess-use-__uaccess_begin_nospec-and-uaccess_try_nospec.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From foo@baz Thu Feb 8 03:32:24 CET 2018 From: Dan Williams <dan.j.williams(a)intel.com> Date: Mon, 29 Jan 2018 17:02:49 -0800 Subject: x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec From: Dan Williams <dan.j.williams(a)intel.com> (cherry picked from commit 304ec1b050310548db33063e567123fae8fd0301) Quoting Linus: I do think that it would be a good idea to very expressly document the fact that it's not that the user access itself is unsafe. I do agree that things like "get_user()" want to be protected, but not because of any direct bugs or problems with get_user() and friends, but simply because get_user() is an excellent source of a pointer that is obviously controlled from a potentially attacking user space. So it's a prime candidate for then finding _subsequent_ accesses that can then be used to perturb the cache. __uaccess_begin_nospec() covers __get_user() and copy_from_iter() where the limit check is far away from the user pointer de-reference. In those cases a barrier_nospec() prevents speculation with a potential pointer to privileged memory. uaccess_try_nospec covers get_user_try. Suggested-by: Linus Torvalds <torvalds(a)linux-foundation.org> Suggested-by: Andi Kleen <ak(a)linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams(a)intel.com> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Cc: linux-arch(a)vger.kernel.org Cc: Kees Cook <keescook(a)chromium.org> Cc: kernel-hardening(a)lists.openwall.com Cc: gregkh(a)linuxfoundation.org Cc: Al Viro <viro(a)zeniv.linux.org.uk> Cc: alan(a)linux.intel.com Link: https://lkml.kernel.org/r/151727416953.33451.10508284228526170604.stgit@dwi… Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- arch/x86/include/asm/uaccess.h | 6 +++--- arch/x86/include/asm/uaccess_32.h | 12 ++++++------ arch/x86/include/asm/uaccess_64.h | 12 ++++++------ arch/x86/lib/usercopy_32.c | 4 ++-- 4 files changed, 17 insertions(+), 17 deletions(-) --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -437,7 +437,7 @@ do { \ ({ \ int __gu_err; \ __inttype(*(ptr)) __gu_val; \ - __uaccess_begin(); \ + __uaccess_begin_nospec(); \ __get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT); \ __uaccess_end(); \ (x) = (__force __typeof__(*(ptr)))__gu_val; \ @@ -547,7 +547,7 @@ struct __large_struct { unsigned long bu * get_user_ex(...); * } get_user_catch(err) */ -#define get_user_try uaccess_try +#define get_user_try uaccess_try_nospec #define get_user_catch(err) uaccess_catch(err) #define get_user_ex(x, ptr) do { \ @@ -582,7 +582,7 @@ extern void __cmpxchg_wrong_size(void) __typeof__(ptr) __uval = (uval); \ __typeof__(*(ptr)) __old = (old); \ __typeof__(*(ptr)) __new = (new); \ - __uaccess_begin(); \ + __uaccess_begin_nospec(); \ switch (size) { \ case 1: \ { \ --- a/arch/x86/include/asm/uaccess_32.h +++ b/arch/x86/include/asm/uaccess_32.h @@ -102,17 +102,17 @@ __copy_from_user(void *to, const void __ switch (n) { case 1: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_size(*(u8 *)to, from, 1, ret, 1); __uaccess_end(); return ret; case 2: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_size(*(u16 *)to, from, 2, ret, 2); __uaccess_end(); return ret; case 4: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_size(*(u32 *)to, from, 4, ret, 4); __uaccess_end(); return ret; @@ -130,17 +130,17 @@ static __always_inline unsigned long __c switch (n) { case 1: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_size(*(u8 *)to, from, 1, ret, 1); __uaccess_end(); return ret; case 2: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_size(*(u16 *)to, from, 2, ret, 2); __uaccess_end(); return ret; case 4: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_size(*(u32 *)to, from, 4, ret, 4); __uaccess_end(); return ret; --- a/arch/x86/include/asm/uaccess_64.h +++ b/arch/x86/include/asm/uaccess_64.h @@ -59,31 +59,31 @@ int __copy_from_user_nocheck(void *dst, return copy_user_generic(dst, (__force void *)src, size); switch (size) { case 1: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_asm(*(u8 *)dst, (u8 __user *)src, ret, "b", "b", "=q", 1); __uaccess_end(); return ret; case 2: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_asm(*(u16 *)dst, (u16 __user *)src, ret, "w", "w", "=r", 2); __uaccess_end(); return ret; case 4: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_asm(*(u32 *)dst, (u32 __user *)src, ret, "l", "k", "=r", 4); __uaccess_end(); return ret; case 8: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_asm(*(u64 *)dst, (u64 __user *)src, ret, "q", "", "=r", 8); __uaccess_end(); return ret; case 10: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_asm(*(u64 *)dst, (u64 __user *)src, ret, "q", "", "=r", 10); if (likely(!ret)) @@ -93,7 +93,7 @@ int __copy_from_user_nocheck(void *dst, __uaccess_end(); return ret; case 16: - __uaccess_begin(); + __uaccess_begin_nospec(); __get_user_asm(*(u64 *)dst, (u64 __user *)src, ret, "q", "", "=r", 16); if (likely(!ret)) --- a/arch/x86/lib/usercopy_32.c +++ b/arch/x86/lib/usercopy_32.c @@ -570,7 +570,7 @@ do { \ unsigned long __copy_to_user_ll(void __user *to, const void *from, unsigned long n) { - __uaccess_begin(); + __uaccess_begin_nospec(); if (movsl_is_ok(to, from, n)) __copy_user(to, from, n); else @@ -627,7 +627,7 @@ EXPORT_SYMBOL(__copy_from_user_ll_nocach unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from, unsigned long n) { - __uaccess_begin(); + __uaccess_begin_nospec(); #ifdef CONFIG_X86_INTEL_USERCOPY if (n > 64 && static_cpu_has(X86_FEATURE_XMM2)) n = __copy_user_intel_nocache(to, from, n); Patches currently in stable-queue which might be from dan.j.williams(a)intel.com are queue-4.9/kvm-vmx-allow-direct-access-to-msr_ia32_spec_ctrl.patch queue-4.9/kvm-x86-add-ibpb-support.patch queue-4.9/kvm-svm-allow-direct-access-to-msr_ia32_spec_ctrl.patch queue-4.9/x86-paravirt-remove-noreplace-paravirt-cmdline-option.patch queue-4.9/documentation-document-array_index_nospec.patch queue-4.9/x86-usercopy-replace-open-coded-stac-clac-with-__uaccess_-begin-end.patch queue-4.9/kvm-x86-make-indirect-calls-in-emulator-speculation-safe.patch queue-4.9/vfs-fdtable-prevent-bounds-check-bypass-via-speculative-execution.patch queue-4.9/x86-uaccess-use-__uaccess_begin_nospec-and-uaccess_try_nospec.patch queue-4.9/x86-implement-array_index_mask_nospec.patch queue-4.9/array_index_nospec-sanitize-speculative-array-de-references.patch queue-4.9/kvm-vmx-make-indirect-call-speculation-safe.patch queue-4.9/x86-kvm-update-spectre-v1-mitigation.patch queue-4.9/x86-get_user-use-pointer-masking-to-limit-speculation.patch queue-4.9/x86-syscall-sanitize-syscall-table-de-references-under-speculation.patch queue-4.9/x86-spectre-report-get_user-mitigation-for-spectre_v1.patch queue-4.9/x86-introduce-barrier_nospec.patch queue-4.9/kvm-vmx-emulate-msr_ia32_arch_capabilities.patch queue-4.9/x86-introduce-__uaccess_begin_nospec-and-uaccess_try_nospec.patch queue-4.9/nl80211-sanitize-array-index-in-parse_txq_params.patch

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