diff options
author | Kees Cook <keescook@chromium.org> | 2023-09-15 23:03:28 +0300 |
---|---|---|
committer | Song Liu <song@kernel.org> | 2023-09-22 21:23:01 +0300 |
commit | e887544d7620f1d3cef017e45df7bc625182caff (patch) | |
tree | dfa8cc15d5238664a195015aa24766f3d9dc7bf5 /drivers/md | |
parent | 54d21eb6ad5e57e70157590397ba01b9faed6b59 (diff) | |
download | linux-e887544d7620f1d3cef017e45df7bc625182caff.tar.xz |
md/md-linear: Annotate struct linear_conf with __counted_by
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 linear_conf.
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: Song Liu <song@kernel.org>
Cc: linux-raid@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230915200328.never.064-kees@kernel.org
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/md-linear.c | 26 | ||||
-rw-r--r-- | drivers/md/md-linear.h | 2 |
2 files changed, 14 insertions, 14 deletions
diff --git a/drivers/md/md-linear.c b/drivers/md/md-linear.c index 71ac99646827..ae2826e9645b 100644 --- a/drivers/md/md-linear.c +++ b/drivers/md/md-linear.c @@ -69,6 +69,19 @@ static struct linear_conf *linear_conf(struct mddev *mddev, int raid_disks) if (!conf) return NULL; + /* + * conf->raid_disks is copy of mddev->raid_disks. The reason to + * keep a copy of mddev->raid_disks in struct linear_conf is, + * mddev->raid_disks may not be consistent with pointers number of + * conf->disks[] when it is updated in linear_add() and used to + * iterate old conf->disks[] earray in linear_congested(). + * Here conf->raid_disks is always consitent with number of + * pointers in conf->disks[] array, and mddev->private is updated + * with rcu_assign_pointer() in linear_addr(), such race can be + * avoided. + */ + conf->raid_disks = raid_disks; + cnt = 0; conf->array_sectors = 0; @@ -112,19 +125,6 @@ static struct linear_conf *linear_conf(struct mddev *mddev, int raid_disks) conf->disks[i-1].end_sector + conf->disks[i].rdev->sectors; - /* - * conf->raid_disks is copy of mddev->raid_disks. The reason to - * keep a copy of mddev->raid_disks in struct linear_conf is, - * mddev->raid_disks may not be consistent with pointers number of - * conf->disks[] when it is updated in linear_add() and used to - * iterate old conf->disks[] earray in linear_congested(). - * Here conf->raid_disks is always consitent with number of - * pointers in conf->disks[] array, and mddev->private is updated - * with rcu_assign_pointer() in linear_addr(), such race can be - * avoided. - */ - conf->raid_disks = raid_disks; - return conf; out: diff --git a/drivers/md/md-linear.h b/drivers/md/md-linear.h index 24e97db50ebb..5587eeedb882 100644 --- a/drivers/md/md-linear.h +++ b/drivers/md/md-linear.h @@ -12,6 +12,6 @@ struct linear_conf struct rcu_head rcu; sector_t array_sectors; int raid_disks; /* a copy of mddev->raid_disks */ - struct dev_info disks[]; + struct dev_info disks[] __counted_by(raid_disks); }; #endif |