Age | Commit message (Collapse) | Author | Files | Lines |
|
`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.
We expect `iclock->name` to be NUL-terminated based on its use within
printk:
| printk(KERN_DEBUG "%s: %s %d\n", __func__, iclock->name,
| iclock->pri);
`iclock` is zero-initialized and as such is already NUL-padded which
means strncpy is doing extra work here by eagerly NUL-padding the
destination buffer.
Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230922-strncpy-drivers-isdn-misdn-clock-c-v1-1-3ba2a5ae627a@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct nfs4_ff_layout_segment.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: linux-nfs@vger.kernel.org
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915201434.never.346-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct nfs4_file_layout_dsaddr.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: linux-nfs@vger.kernel.org
Link: https://lore.kernel.org/r/20230915201427.never.771-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct dm_bio_prison.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: dm-devel@redhat.com
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915200407.never.611-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct dm_stat.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: dm-devel@redhat.com
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915200400.never.585-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct stripe_c.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: dm-devel@redhat.com
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915200352.never.118-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct crypt_config.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: dm-devel@redhat.com
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915200344.never.272-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct raid_set.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: dm-devel@redhat.com
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915200335.never.098-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct fifo_buffer.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915200316.never.707-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct f_midi.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: John Keeping <john@keeping.me.uk>
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Hulk Robot <hulkci@huawei.com>
Cc: Allen Pais <allen.lkml@gmail.com>
Cc: Will McVicker <willmcvicker@google.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Zhang Qilong <zhangqilong3@huawei.com>
Cc: linux-usb@vger.kernel.org
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915195938.never.611-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct ffs_buffer.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: John Keeping <john@keeping.me.uk>
Cc: Udipto Goswami <quic_ugoswami@quicinc.com>
Cc: Linyu Yuan <quic_linyyuan@quicinc.com>
Cc: linux-usb@vger.kernel.org
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915195849.never.275-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct urb_priv.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: linux-usb@vger.kernel.org
Link: https://lore.kernel.org/r/20230915195812.never.371-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct afs_addr_list.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: David Howells <dhowells@redhat.com>
Cc: Marc Dionne <marc.dionne@auristor.com>
Cc: linux-afs@lists.infradead.org
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915201449.never.649-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct afs_permits.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: David Howells <dhowells@redhat.com>
Cc: Marc Dionne <marc.dionne@auristor.com>
Cc: linux-afs@lists.infradead.org
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915201456.never.529-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct ceph_osd_request.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Xiubo Li <xiubli@redhat.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: ceph-devel@vger.kernel.org
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Link: https://lore.kernel.org/r/20230915201517.never.373-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct ocfs2_slot_info.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: ocfs2-devel@lists.linux.dev
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230915201522.never.979-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
If, for any reason, the open-coded arithmetic causes a wraparound,
the protection that `struct_size()` adds against potential integer
overflows is defeated. Fix this by hardening call to `struct_size()`
with `size_add()`.
Fixes: b626871a7cda ("usb: atm: Use struct_size() helper")
Signed-off-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/ZQSuboEIhvATAdxN@work
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
If, for any reason, the open-coded arithmetic causes a wraparound, the
protection that `struct_size()` adds against potential integer overflows
is defeated. Fix this by hardening call to `struct_size()` with `size_add()`.
Fixes: 40e1a70b4aed ("drm: Add GUD USB Display driver")
Signed-off-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/ZQSlyHKPdw/zsy4c@work
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We've already calculated bounds, possible truncation with '\0' or '\n'
and manually NUL-terminated. The situation is now just a literal byte
copy from one buffer to another, let's treat it as such and use a less
ambiguous interface in memcpy.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230918-strncpy-drivers-edac-edac_mc_sysfs-c-v4-1-38a23d2fcdd8@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We should prefer more robust and less ambiguous string interfaces.
A suitable replacement is `strscpy` [2] due to the fact that it
guarantees NUL-termination on the destination buffer without
unnecessarily NUL-padding. If, for any reason, NUL-padding is needed
let's opt for `strscpy_pad`.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230914-strncpy-drivers-hwmon-asus_wmi_sensors-c-v1-1-e1703cf91693@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
A suitable replacement is `memcpy` as we've already precisely calculated
the number of bytes to copy while `buf` has been explicitly
zero-initialized:
| char buf[8] = { 0 };
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230919-strncpy-drivers-hwmon-ibmpowernv-c-v2-1-37d3e64172bc@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We should prefer more robust and less ambiguous string interfaces.
A suitable replacement is `strscpy` [2] due to the fact that it guarantees
NUL-termination on the destination buffer without unnecessarily NUL-padding.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230914-strncpy-drivers-hid-hid-prodikeys-c-v1-1-10c00550f2c2@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We should prefer more robust and less ambiguous string interfaces.
It seems like the filename stored at `namevirt` is expected to be
NUL-terminated.
A suitable replacement is `strscpy_pad` due to the fact that it
guarantees NUL-termination on the destination buffer whilst maintaining
the NUL-padding behavior that strncpy provides.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230913-strncpy-drivers-firmware-tegra-bpmp-debugfs-c-v1-1-828b0a8914b5@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We should prefer more robust and less ambiguous string interfaces.
A suitable replacement is `strscpy` [2] due to the fact that it guarantees
NUL-termination on the destination buffer. With this, we can also drop
the now unnecessary `CPUIDLE_(NAME|DESC)_LEN - 1` pieces.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230913-strncpy-drivers-cpuidle-dt_idle_states-c-v1-1-d16a0dbe5658@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We should prefer more robust and less ambiguous string interfaces.
Both `policy->last_governor` and `default_governor` are expected to be
NUL-terminated which is shown by their heavy usage with other string
apis like `strcmp`.
A suitable replacement is `strscpy` [2] due to the fact that it guarantees
NUL-termination on the destination buffer.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/20230913-strncpy-drivers-cpufreq-cpufreq-c-v1-1-f1608bfeff63@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We need to prefer more robust and less ambiguous string interfaces.
`obj_desc->(type|label)` are expected to be NUL-terminated strings as
per "include/linux/fsl/mc.h +143"
| ...
| * struct fsl_mc_obj_desc - Object descriptor
| * @type: Type of object: NULL terminated string
| ...
It seems `cmd_params->obj_type` is also expected to be a NUL-terminated string.
A suitable replacement is `strscpy_pad` due to the fact that it
guarantees NUL-termination on the destination buffer whilst keeping the
NUL-padding behavior that `strncpy` provides.
Padding may not strictly be necessary but let's opt to keep it as this
ensures no functional change.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230912-strncpy-drivers-bus-fsl-mc-dprc-c-v1-1-cdb56aa3f4f4@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated and as such we should prefer more robust and
less ambiguous interfaces.
In this case, all of `press_str`, `repeat_str` and `release_str` are
explicitly marked as nonstring:
| struct { /* valid when type == INPUT_TYPE_KBD */
| char press_str[sizeof(void *) + sizeof(int)] __nonstring;
| char repeat_str[sizeof(void *) + sizeof(int)] __nonstring;
| char release_str[sizeof(void *) + sizeof(int)] __nonstring;
| } kbd;
... which makes `strtomem_pad` a suitable replacement as it is
functionally the same whilst being more obvious about its behavior.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230911-strncpy-drivers-auxdisplay-panel-c-v1-1-b60bd0ae8552@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
`strncpy` is deprecated for use on NUL-terminated destination strings [1].
`gate_buf` should always be NUL-terminated and does not require
NUL-padding. It is used as a string arg inside an argv array given to
`run_helper()`. Due to this, let's use `strscpy` as it guarantees
NUL-terminated on the destination buffer preventing potential buffer
overreads [2].
This exact invocation was changed from `strcpy` to `strncpy` in commit
7879b1d94badb ("um,ethertap: use strncpy") back in 2015. Let's continue
hardening our `str*cpy` apis and use the newer and safer `strscpy`!
Link: www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings[1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230911-strncpy-arch-um-os-linux-drivers-ethertap_user-c-v1-1-d9e53f52ab32@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
atomic_t variables are currently used to implement reference counters
with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows and
underflows. This is important since overflows and underflows can lead
to use-after-free situation and be exploitable.
The variable group_info.usage is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
**Important note for maintainers:
Some functions from refcount_t API defined in refcount.h have different
memory ordering guarantees than their atomic counterparts. Please check
Documentation/core-api/refcount-vs-atomic.rst for more information.
Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in some
rare cases it might matter. Please double check that you don't have
some undocumented memory guarantees for this variable usage.
For the group_info.usage it might make a difference in following places:
- put_group_info(): decrement in refcount_dec_and_test() only
provides RELEASE ordering and ACQUIRE ordering on success vs. fully
ordered atomic counterpart
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Link: https://lore.kernel.org/r/20230818041456.gonna.009-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Fix checkpatch.pl ERROR: do not use assignment in if condition.
Signed-off-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/6b900e80b5587187c68efc788f5b042ca747d374.1692208802.git.gustavoars@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
One-element and zero-length arrays are deprecated. So, replace
one-element array in struct nouveau_svm with flexible-array member.
This results in no differences in binary output.
Link: https://github.com/KSPP/linux/issues/338
Signed-off-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/087a1c335228bd245192bbb2fb347c9af1be5750.1692208802.git.gustavoars@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
It's an oversight to not have already listed Gustavo here. Add him as a
Reviewer.
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct ivpu_job.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Cc: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Cc: Oded Gabbay <ogabbay@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Tom Rix <trix@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: llvm@lists.linux.dev
Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Link: https://lore.kernel.org/r/20230922175416.work.272-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Since __counted_by annotations may also require that code be changed to
get initialization ordering correct, let's get an extra group of eyes on
code that is working on these annotations.
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
The lkdtm selftest config fragment enables CONFIG_UBSAN_TRAP to make the
ARRAY_BOUNDS test kill the calling process when an out-of-bound access
is detected by UBSAN. However, after this [1] commit, UBSAN is triggered
under many new scenarios that weren't detected before, such as in struct
definitions with fixed-size trailing arrays used as flexible arrays. As
a result, CONFIG_UBSAN_TRAP=y has become a very aggressive option to
enable except for specific situations.
`make kselftest-merge` applies CONFIG_UBSAN_TRAP=y to the kernel config
for all selftests, which makes many of them fail because of system hangs
during boot.
This change removes the config option from the lkdtm kselftest and
configures the ARRAY_BOUNDS test to look for UBSAN reports rather than
relying on the calling process being killed.
[1] commit 2d47c6956ab3 ("ubsan: Tighten UBSAN_BOUNDS on GCC")'
Signed-off-by: Ricardo Cañuelo <ricardo.canuelo@collabora.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230802063252.1917997-1-ricardo.canuelo@collabora.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Upon a panic() the kernel will use either smp_send_stop() or
crash_smp_send_stop() to attempt to stop secondary CPUs via an IPI,
which may or may not be an NMI. Generally it's preferable that this is an
NMI so that CPUs can be stopped in as many situations as possible, but
it's not always possible to provide an NMI, and there are cases where
CPUs may be unable to handle the NMI regardless.
This patch adds a test for panic() where all other CPUs are stuck with
interrupts disabled, which can be used to check whether the kernel
gracefully handles CPUs failing to respond to a stop, and whether NMIs
actually work to stop CPUs.
For example, on arm64 *without* an NMI, this results in:
| # echo PANIC_STOP_IRQOFF > /sys/kernel/debug/provoke-crash/DIRECT
| lkdtm: Performing direct entry PANIC_STOP_IRQOFF
| Kernel panic - not syncing: panic stop irqoff test
| CPU: 2 PID: 24 Comm: migration/2 Not tainted 6.5.0-rc3-00077-ge6c782389895-dirty #4
| Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
| Stopper: multi_cpu_stop+0x0/0x1a0 <- stop_machine_cpuslocked+0x158/0x1a4
| Call trace:
| dump_backtrace+0x94/0xec
| show_stack+0x18/0x24
| dump_stack_lvl+0x74/0xc0
| dump_stack+0x18/0x24
| panic+0x358/0x3e8
| lkdtm_PANIC+0x0/0x18
| multi_cpu_stop+0x9c/0x1a0
| cpu_stopper_thread+0x84/0x118
| smpboot_thread_fn+0x224/0x248
| kthread+0x114/0x118
| ret_from_fork+0x10/0x20
| SMP: stopping secondary CPUs
| SMP: failed to stop secondary CPUs 0-3
| Kernel Offset: 0x401cf3490000 from 0xffff80008000000c0
| PHYS_OFFSET: 0x40000000
| CPU features: 0x00000000,68c167a1,cce6773f
| Memory Limit: none
| ---[ end Kernel panic - not syncing: panic stop irqoff test ]---
Note the "failed to stop secondary CPUs 0-3" message.
On arm64 *with* an NMI, this results in:
| # echo PANIC_STOP_IRQOFF > /sys/kernel/debug/provoke-crash/DIRECT
| lkdtm: Performing direct entry PANIC_STOP_IRQOFF
| Kernel panic - not syncing: panic stop irqoff test
| CPU: 1 PID: 19 Comm: migration/1 Not tainted 6.5.0-rc3-00077-ge6c782389895-dirty #4
| Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
| Stopper: multi_cpu_stop+0x0/0x1a0 <- stop_machine_cpuslocked+0x158/0x1a4
| Call trace:
| dump_backtrace+0x94/0xec
| show_stack+0x18/0x24
| dump_stack_lvl+0x74/0xc0
| dump_stack+0x18/0x24
| panic+0x358/0x3e8
| lkdtm_PANIC+0x0/0x18
| multi_cpu_stop+0x9c/0x1a0
| cpu_stopper_thread+0x84/0x118
| smpboot_thread_fn+0x224/0x248
| kthread+0x114/0x118
| ret_from_fork+0x10/0x20
| SMP: stopping secondary CPUs
| Kernel Offset: 0x55a9c0bc0000 from 0xffff800080000000
| PHYS_OFFSET: 0x40000000
| CPU features: 0x00000000,68c167a1,fce6773f
| Memory Limit: none
| ---[ end Kernel panic - not syncing: panic stop irqoff test ]---
Note the absence of a "failed to stop secondary CPUs" message, since we
don't log anything when secondary CPUs are successfully stopped.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20230921161634.4063233-1-mark.rutland@arm.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
Direct replacement is safe here since return value of -errno
is used to check for truncation instead of sizeof(dest).
[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89
Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230831140104.207019-1-azeemshaikh38@gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
Direct replacement is safe here since return value of -errno
is used to check for truncation instead of sizeof(dest).
[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89
Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230830160806.3821893-1-azeemshaikh38@gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Inspired by Salvatore Mesoraca's earlier[1] efforts to provide some
in-tree guidance for kernel hardening Kconfig options, add a new fragment
named "hardening-basic.config" (along with some arch-specific fragments)
that enable a basic set of kernel hardening options that have the least
(or no) performance impact and remove a reasonable set of legacy APIs.
Using this fragment is as simple as running "make hardening.config".
More extreme fragments can be added[2] in the future to cover all the
recognized hardening options, and more per-architecture files can be
added too.
For now, document the fragments directly via comments. Perhaps .rst
documentation can be generated from them in the future (rather than the
other way around).
[1] https://lore.kernel.org/kernel-hardening/1536516257-30871-1-git-send-email-s.mesoraca16@gmail.com/
[2] https://github.com/KSPP/linux/issues/14
Cc: Salvatore Mesoraca <s.mesoraca16@gmail.com>
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
|
|
The choose_32_64() macros were added to deal with an odd inconsistency
between the 32-bit and 64-bit layout of 'struct stat' way back when in
commit a52dd971f947 ("vfs: de-crapify "cp_new_stat()" function").
Then a decade later Mikulas noticed that said inconsistency had been a
mistake in the early x86-64 port, and shouldn't have existed in the
first place. So commit 932aba1e1690 ("stat: fix inconsistency between
struct stat and struct compat_stat") removed the uses of the helpers.
But the helpers remained around, unused.
Get rid of them.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
-flto* implies -ffunction-sections. With LTO enabled, ld.lld generates
multiple .text sections for purgatory.ro:
$ readelf -S purgatory.ro | grep " .text"
[ 1] .text PROGBITS 0000000000000000 00000040
[ 7] .text.purgatory PROGBITS 0000000000000000 000020e0
[ 9] .text.warn PROGBITS 0000000000000000 000021c0
[13] .text.sha256_upda PROGBITS 0000000000000000 000022f0
[15] .text.sha224_upda PROGBITS 0000000000000000 00002be0
[17] .text.sha256_fina PROGBITS 0000000000000000 00002bf0
[19] .text.sha224_fina PROGBITS 0000000000000000 00002cc0
This causes WARNING from kexec_purgatory_setup_sechdrs():
WARNING: CPU: 26 PID: 110894 at kernel/kexec_file.c:919
kexec_load_purgatory+0x37f/0x390
Fix this by disabling LTO for purgatory.
[ AFAICT, x86 is the only arch that supports LTO and purgatory. ]
We could also fix this with an explicit linker script to rejoin .text.*
sections back into .text. However, given the benefit of LTOing purgatory
is small, simply disable the production of more .text.* sections for now.
Fixes: b33fff07e3e3 ("x86, build: allow LTO to be selected")
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/r/20230914170138.995606-1-song@kernel.org
|
|
The decompressor has a hard limit on the number of page tables it can
allocate. This limit is defined at compile-time and will cause boot
failure if it is reached.
The kernel is very strict and calculates the limit precisely for the
worst-case scenario based on the current configuration. However, it is
easy to forget to adjust the limit when a new use-case arises. The
worst-case scenario is rarely encountered during sanity checks.
In the case of enabling 5-level paging, a use-case was overlooked. The
limit needs to be increased by one to accommodate the additional level.
This oversight went unnoticed until Aaron attempted to run the kernel
via kexec with 5-level paging and unaccepted memory enabled.
Update wost-case calculations to include 5-level paging.
To address this issue, let's allocate some extra space for page tables.
128K should be sufficient for any use-case. The logic can be simplified
by using a single value for all kernel configurations.
[ Also add a warning, should this memory run low - by Dave Hansen. ]
Fixes: 34bbb0009f3b ("x86/boot/compressed: Enable 5-level paging during decompression stage")
Reported-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230915070221.10266-1-kirill.shutemov@linux.intel.com
|
|
Commit 408579cd627a ("mm: Update do_vmi_align_munmap() return
semantics") seems to have updated one of the callers of do_vmi_munmap()
incorrectly: it used to check for the error case (which didn't
change: negative means error).
That commit changed the check to the success case (which did change:
before that commit, 0 was success, and 1 was "success and lock
downgraded". After the change, it's always 0 for success, and the lock
will have been released if requested).
This didn't change any actual VM behavior _except_ for memory accounting
when 'VM_ACCOUNT' was set on the vma. Which made the wrong return value
test fairly subtle, since everything continues to work.
Or rather - it continues to work but the "Committed memory" accounting
goes all wonky (Committed_AS value in /proc/meminfo), and depending on
settings that then causes problems much much later as the VM relies on
bogus statistics for its heuristics.
Revert that one line of the change back to the original logic.
Fixes: 408579cd627a ("mm: Update do_vmi_align_munmap() return semantics")
Reported-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Reported-bisected-and-tested-by: Michael Labiuk <michael.labiuk@virtuozzo.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Link: https://lore.kernel.org/all/1694366957@msgid.manchmal.in-ulm.de/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Currently, we fetch sense data for a _successful_ command if either:
1) Command was NCQ and ATA_DFLAG_CDL_ENABLED flag set (flag
ATA_DFLAG_CDL_ENABLED will only be set if the Successful NCQ command
sense data supported bit is set); or
2) Command was non-NCQ and regular sense data reporting is enabled.
This means that case 2) will trigger for a non-NCQ command which has
ATA_SENSE bit set, regardless if CDL is enabled or not.
This decision was by design. If the device reports that it has sense data
available, it makes sense to fetch that sense data, since the sk/asc/ascq
could be important information regardless if CDL is enabled or not.
However, the fetching of sense data for a successful command is done via
ATA EH. Considering how intricate the ATA EH is, we really do not want to
invoke ATA EH unless absolutely needed.
Before commit 18bd7718b5c4 ("scsi: ata: libata: Handle completion of CDL
commands using policy 0xD") we never fetched sense data for successful
commands.
In order to not invoke the ATA EH unless absolutely necessary, even if the
device claims support for sense data reporting, only fetch sense data for
successful (NCQ and non-NCQ commands) commands that are using CDL.
[Damien] Modified the check to test the qc flag ATA_QCFLAG_HAS_CDL
instead of the device support for CDL, which is implied for commands
using CDL.
Fixes: 3ac873c76d79 ("ata: libata-core: fix when to fetch sense data for successful commands")
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
|
|
commit 1e641060c4b5 ("libata: clear eh_info on reset completion") added
a workaround that broke the retry mechanism in ATA EH.
Tejun himself suggested to remove this workaround when it was identified
to cause additional problems:
https://lore.kernel.org/linux-ide/20110426135027.GI878@htj.dyndns.org/
He even said:
"Hmm... it seems I wasn't thinking straight when I added that work around."
https://lore.kernel.org/linux-ide/20110426155229.GM878@htj.dyndns.org/
While removing the workaround solved the issue, however, the workaround was
kept to avoid "spurious hotplug events during reset", and instead another
workaround was added on top of the existing workaround in commit
8c56cacc724c ("libata: fix unexpectedly frozen port after ata_eh_reset()").
Because these IRQs happened when the port was frozen, we know that they
were actually a side effect of PxIS and IS.IPS(x) not being cleared before
the COMRESET. This is now done in commit 94152042eaa9 ("ata: libahci: clear
pending interrupt status"), so these workarounds can now be removed.
Since commit 1e641060c4b5 ("libata: clear eh_info on reset completion") has
now been reverted, the ATA EH retry mechanism is functional again, so there
is once again no need to thaw the port more than once in ata_eh_reset().
This reverts "the workaround on top of the workaround" introduced in commit
8c56cacc724c ("libata: fix unexpectedly frozen port after ata_eh_reset()").
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
|
|
ata_scsi_port_error_handler() starts off by clearing ATA_PFLAG_EH_PENDING,
before calling ap->ops->error_handler() (without holding the ap->lock).
If an error IRQ is received while ap->ops->error_handler() is running,
the irq handler will set ATA_PFLAG_EH_PENDING.
Once ap->ops->error_handler() returns, ata_scsi_port_error_handler()
checks if ATA_PFLAG_EH_PENDING is set, and if it is, another iteration
of ATA EH is performed.
The problem is that ATA_PFLAG_EH_PENDING is not only cleared by
ata_scsi_port_error_handler(), it is also cleared by ata_eh_reset().
ata_eh_reset() is called by ap->ops->error_handler(). This additional
clearing done by ata_eh_reset() breaks the whole retry logic in
ata_scsi_port_error_handler(). Thus, if an error IRQ is received while
ap->ops->error_handler() is running, the port will currently remain
frozen and will never get re-enabled.
The additional clearing in ata_eh_reset() was introduced in commit
1e641060c4b5 ("libata: clear eh_info on reset completion").
Looking at the original error report:
https://marc.info/?l=linux-ide&m=124765325828495&w=2
We can see the following happening:
[ 1.074659] ata3: XXX port freeze
[ 1.074700] ata3: XXX hardresetting link, stopping engine
[ 1.074746] ata3: XXX flipping SControl
[ 1.411471] ata3: XXX irq_stat=400040 CONN|PHY
[ 1.411475] ata3: XXX port freeze
[ 1.420049] ata3: XXX starting engine
[ 1.420096] ata3: XXX rc=0, class=1
[ 1.420142] ata3: XXX clearing IRQs for thawing
[ 1.420188] ata3: XXX port thawed
[ 1.420234] ata3: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
We are not supposed to be able to receive an error IRQ while the port is
frozen (PxIE is set to 0, i.e. all IRQs for the port are disabled).
AHCI 1.3.1 section 10.7.1.1 First Tier (IS Register) states:
"Each bit location can be thought of as reporting a '1' if the virtual
"interrupt line" for that port is indicating it wishes to generate an
interrupt. That is, if a port has one or more interrupt status bit set,
and the enables for those status bits are set, then this bit shall be set."
Additionally, AHCI state P:ComInit clearly shows that the state machine
will only jump to P:ComInitSetIS (which sets IS.IPS(x) to '1'), if PxIE.PCE
is set to '1'. In our case, PxIE is set to 0, so IS.IPS(x) won't get set.
So IS.IPS(x) only gets set if PxIS and PxIE is set.
AHCI 1.3.1 section 10.7.1.1 First Tier (IS Register) also states:
"The bits in this register are read/write clear. It is set by the level of
the virtual interrupt line being a set, and cleared by a write of '1' from
the software."
So if IS.IPS(x) is set, you need to explicitly clear it by writing a 1 to
IS.IPS(x) for that port.
Since PxIE is cleared, the only way to get an interrupt while the port is
frozen, is if IS.IPS(x) is set, and the only way IS.IPS(x) can be set when
the port is frozen, is if it was set before the port was frozen.
However, since commit 737dd811a3db ("ata: libahci: clear pending interrupt
status"), we clear both PxIS and IS.IPS(x) after freezing the port, but
before the COMRESET, so the problem that commit 1e641060c4b5 ("libata:
clear eh_info on reset completion") fixed can no longer happen.
Thus, revert commit 1e641060c4b5 ("libata: clear eh_info on reset
completion"), so that the retry logic in ata_scsi_port_error_handler()
works once again. (The retry logic is still needed, since we can still
get an error IRQ _after_ the port has been thawed, but before
ata_scsi_port_error_handler() takes the ap->lock in order to check
if ATA_PFLAG_EH_PENDING is set.)
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
|
|
dm looks up the table for IO based on the request type, with an
assumption that if the request is marked REQ_NOWAIT, it's fine to
attempt to submit that IO while under RCU read lock protection. This
is not OK, as REQ_NOWAIT just means that we should not be sleeping
waiting on other IO, it does not mean that we can't potentially
schedule.
A simple test case demonstrates this quite nicely:
int main(int argc, char *argv[])
{
struct iovec iov;
int fd;
fd = open("/dev/dm-0", O_RDONLY | O_DIRECT);
posix_memalign(&iov.iov_base, 4096, 4096);
iov.iov_len = 4096;
preadv2(fd, &iov, 1, 0, RWF_NOWAIT);
return 0;
}
which will instantly spew:
BUG: sleeping function called from invalid context at include/linux/sched/mm.h:306
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 5580, name: dm-nowait
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
INFO: lockdep is turned off.
CPU: 7 PID: 5580 Comm: dm-nowait Not tainted 6.6.0-rc1-g39956d2dcd81 #132
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x11d/0x1b0
__might_resched+0x3c3/0x5e0
? preempt_count_sub+0x150/0x150
mempool_alloc+0x1e2/0x390
? mempool_resize+0x7d0/0x7d0
? lock_sync+0x190/0x190
? lock_release+0x4b7/0x670
? internal_get_user_pages_fast+0x868/0x2d40
bio_alloc_bioset+0x417/0x8c0
? bvec_alloc+0x200/0x200
? internal_get_user_pages_fast+0xb8c/0x2d40
bio_alloc_clone+0x53/0x100
dm_submit_bio+0x27f/0x1a20
? lock_release+0x4b7/0x670
? blk_try_enter_queue+0x1a0/0x4d0
? dm_dax_direct_access+0x260/0x260
? rcu_is_watching+0x12/0xb0
? blk_try_enter_queue+0x1cc/0x4d0
__submit_bio+0x239/0x310
? __bio_queue_enter+0x700/0x700
? kvm_clock_get_cycles+0x40/0x60
? ktime_get+0x285/0x470
submit_bio_noacct_nocheck+0x4d9/0xb80
? should_fail_request+0x80/0x80
? preempt_count_sub+0x150/0x150
? lock_release+0x4b7/0x670
? __bio_add_page+0x143/0x2d0
? iov_iter_revert+0x27/0x360
submit_bio_noacct+0x53e/0x1b30
submit_bio_wait+0x10a/0x230
? submit_bio_wait_endio+0x40/0x40
__blkdev_direct_IO_simple+0x4f8/0x780
? blkdev_bio_end_io+0x4c0/0x4c0
? stack_trace_save+0x90/0xc0
? __bio_clone+0x3c0/0x3c0
? lock_release+0x4b7/0x670
? lock_sync+0x190/0x190
? atime_needs_update+0x3bf/0x7e0
? timestamp_truncate+0x21b/0x2d0
? inode_owner_or_capable+0x240/0x240
blkdev_direct_IO.part.0+0x84a/0x1810
? rcu_is_watching+0x12/0xb0
? lock_release+0x4b7/0x670
? blkdev_read_iter+0x40d/0x530
? reacquire_held_locks+0x4e0/0x4e0
? __blkdev_direct_IO_simple+0x780/0x780
? rcu_is_watching+0x12/0xb0
? __mark_inode_dirty+0x297/0xd50
? preempt_count_add+0x72/0x140
blkdev_read_iter+0x2a4/0x530
do_iter_readv_writev+0x2f2/0x3c0
? generic_copy_file_range+0x1d0/0x1d0
? fsnotify_perm.part.0+0x25d/0x630
? security_file_permission+0xd8/0x100
do_iter_read+0x31b/0x880
? import_iovec+0x10b/0x140
vfs_readv+0x12d/0x1a0
? vfs_iter_read+0xb0/0xb0
? rcu_is_watching+0x12/0xb0
? rcu_is_watching+0x12/0xb0
? lock_release+0x4b7/0x670
do_preadv+0x1b3/0x260
? do_readv+0x370/0x370
__x64_sys_preadv2+0xef/0x150
do_syscall_64+0x39/0xb0
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f5af41ad806
Code: 41 54 41 89 fc 55 44 89 c5 53 48 89 cb 48 83 ec 18 80 3d e4 dd 0d 00 00 74 7a 45 89 c1 49 89 ca 45 31 c0 b8 47 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 be 00 00 00 48 85 c0 79 4a 48 8b 0d da 55
RSP: 002b:00007ffd3145c7f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000147
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5af41ad806
RDX: 0000000000000001 RSI: 00007ffd3145c850 RDI: 0000000000000003
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000008
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007ffd3145c850 R14: 000055f5f0431dd8 R15: 0000000000000001
</TASK>
where in fact it is dm itself that attempts to allocate a bio clone with
GFP_NOIO under the rcu read lock, regardless of the request type.
Fix this by getting rid of the special casing for REQ_NOWAIT, and just
use the normal SRCU protected table lookup. Get rid of the bio based
table locking helpers at the same time, as they are now unused.
Cc: stable@vger.kernel.org
Fixes: 563a225c9fd2 ("dm: introduce dm_{get,put}_live_table_bio called from dm_submit_bio")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
|
|
This reverts commit 06f45435d985d60d7d2fe2424fbb9909d177a63d.
John Ogness reports the case that the allocation is in atomic context under
acquired spin-lock.
[ 12.555784] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:306
[ 12.555808] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 70, name: kworker/1:2
[ 12.555814] preempt_count: 1, expected: 0
[ 12.555820] INFO: lockdep is turned off.
[ 12.555824] irq event stamp: 208
[ 12.555828] hardirqs last enabled at (207): [<c00000000111e414>] ._raw_spin_unlock_irq+0x44/0x80
[ 12.555850] hardirqs last disabled at (208): [<c00000000110ff94>] .__schedule+0x854/0xfe0
[ 12.555859] softirqs last enabled at (188): [<c000000000f73504>] .addrconf_verify_rtnl+0x2c4/0xb70
[ 12.555872] softirqs last disabled at (182): [<c000000000f732b0>] .addrconf_verify_rtnl+0x70/0xb70
[ 12.555884] CPU: 1 PID: 70 Comm: kworker/1:2 Tainted: G S 6.6.0-rc1 #1
[ 12.555893] Hardware name: PowerMac7,2 PPC970 0x390202 PowerMac
[ 12.555898] Workqueue: firewire_ohci .bus_reset_work [firewire_ohci]
[ 12.555939] Call Trace:
[ 12.555944] [c000000009677830] [c0000000010d83c0] .dump_stack_lvl+0x8c/0xd0 (unreliable)
[ 12.555963] [c0000000096778b0] [c000000000140270] .__might_resched+0x320/0x340
[ 12.555978] [c000000009677940] [c000000000497600] .__kmem_cache_alloc_node+0x390/0x460
[ 12.555993] [c000000009677a10] [c0000000003fe620] .__kmalloc+0x70/0x310
[ 12.556007] [c000000009677ac0] [c0003d00004e2268] .fw_core_handle_bus_reset+0x2c8/0xba0 [firewire_core]
[ 12.556060] [c000000009677c20] [c0003d0000491190] .bus_reset_work+0x330/0x9b0 [firewire_ohci]
[ 12.556079] [c000000009677d10] [c00000000011d0d0] .process_one_work+0x280/0x6f0
[ 12.556094] [c000000009677e10] [c00000000011d8a0] .worker_thread+0x360/0x500
[ 12.556107] [c000000009677ef0] [c00000000012e3b4] .kthread+0x154/0x160
[ 12.556120] [c000000009677f90] [c00000000000bfa8] .start_kernel_thread+0x10/0x14
Cc: stable@kernel.org
Reported-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/lkml/87jzsuv1xk.fsf@jogness.linutronix.de/raw
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
|
|
Commit:
5a5d7e9badd2 ("cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG")
amended warn_slowpath_fmt() to disable preemption until the WARN splat
has been emitted.
However the commit neglected to reenable preemption in the !fmt codepath,
i.e. when a WARN splat is emitted without additional format string.
One consequence is that users may see more splats than intended. E.g. a
WARN splat emitted in a work item results in at least two extra splats:
BUG: workqueue leaked lock or atomic
(emitted by process_one_work())
BUG: scheduling while atomic
(emitted by worker_thread() -> schedule())
Ironically the point of the commit was to *avoid* extra splats. ;)
Fix it.
Fixes: 5a5d7e9badd2 ("cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/3ec48fde01e4ee6505f77908ba351bad200ae3d1.1694763684.git.lukas@wunner.de
|