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| author | Jeremy Cline <jcline@redhat.com> | 2018-07-31 04:37:31 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-09 20:56:02 +0300 |
| commit | 3098933c12130afd50c7474ee3e7318aecce3297 (patch) | |
| tree | 0cce7f45c4d4fe20e8bb3268361c082ab539cc1b /fs | |
| parent | 0682e027f39dfcdef5f5d9c264491a34196f3b25 (diff) | |
| download | linux-3098933c12130afd50c7474ee3e7318aecce3297.tar.xz | |
fs/quota: Fix spectre gadget in do_quotactl
commit 7b6924d94a60c6b8c1279ca003e8744e6cd9e8b1 upstream.
'type' is user-controlled, so sanitize it after the bounds check to
avoid using it in speculative execution. This covers the following
potential gadgets detected with the help of smatch:
* fs/ext4/super.c:5741 ext4_quota_read() warn: potential spectre issue
'sb_dqopt(sb)->files' [r]
* fs/ext4/super.c:5778 ext4_quota_write() warn: potential spectre issue
'sb_dqopt(sb)->files' [r]
* fs/f2fs/super.c:1552 f2fs_quota_read() warn: potential spectre issue
'sb_dqopt(sb)->files' [r]
* fs/f2fs/super.c:1608 f2fs_quota_write() warn: potential spectre issue
'sb_dqopt(sb)->files' [r]
* fs/quota/dquot.c:412 mark_info_dirty() warn: potential spectre issue
'sb_dqopt(sb)->info' [w]
* fs/quota/dquot.c:933 dqinit_needed() warn: potential spectre issue
'dquots' [r]
* fs/quota/dquot.c:2112 dquot_commit_info() warn: potential spectre
issue 'dqopt->ops' [r]
* fs/quota/dquot.c:2362 vfs_load_quota_inode() warn: potential spectre
issue 'dqopt->files' [w] (local cap)
* fs/quota/dquot.c:2369 vfs_load_quota_inode() warn: potential spectre
issue 'dqopt->ops' [w] (local cap)
* fs/quota/dquot.c:2370 vfs_load_quota_inode() warn: potential spectre
issue 'dqopt->info' [w] (local cap)
* fs/quota/quota.c:110 quota_getfmt() warn: potential spectre issue
'sb_dqopt(sb)->info' [r]
* fs/quota/quota_v2.c:84 v2_check_quota_file() warn: potential spectre
issue 'quota_magics' [w]
* fs/quota/quota_v2.c:85 v2_check_quota_file() warn: potential spectre
issue 'quota_versions' [w]
* fs/quota/quota_v2.c:96 v2_read_file_info() warn: potential spectre
issue 'dqopt->info' [r]
* fs/quota/quota_v2.c:172 v2_write_file_info() warn: potential spectre
issue 'dqopt->info' [r]
Additionally, a quick inspection indicates there are array accesses with
'type' in quota_on() and quota_off() functions which are also addressed
by this.
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/quota/quota.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/quota/quota.c b/fs/quota/quota.c index 43612e2a73af..3f02bab0db4e 100644 --- a/fs/quota/quota.c +++ b/fs/quota/quota.c @@ -18,6 +18,7 @@ #include <linux/quotaops.h> #include <linux/types.h> #include <linux/writeback.h> +#include <linux/nospec.h> static int check_quotactl_permission(struct super_block *sb, int type, int cmd, qid_t id) @@ -703,6 +704,7 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id, if (type >= (XQM_COMMAND(cmd) ? XQM_MAXQUOTAS : MAXQUOTAS)) return -EINVAL; + type = array_index_nospec(type, MAXQUOTAS); /* * Quota not supported on this fs? Check this before s_quota_types * since they needn't be set if quota is not supported at all. |