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Fix CVE-2018-13053 CVE-2018-12896 CVE-2018-13093 CVE-2018-13094 CVE-2018-13095

This commit is contained in:
Justin M. Forbes 2018-07-05 09:31:30 -05:00
parent 4723878682
commit 5ec032cfa0
7 changed files with 643 additions and 0 deletions
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141
0001-xfs-More-robust-inode-extent-count-validation.patch Normal file
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@ -0,0 +1,141 @@
From 23fcb3340d033d9f081e21e6c12c2db7eaa541d3 Mon Sep 17 00:00:00 2001
From: Dave Chinner <dchinner@redhat.com>
Date: Thu, 21 Jun 2018 23:25:57 -0700
Subject: [PATCH] xfs: More robust inode extent count validation
When the inode is in extent format, it can't have more extents that
fit in the inode fork. We don't currenty check this, and so this
corruption goes unnoticed by the inode verifiers. This can lead to
crashes operating on invalid in-memory structures.
Attempts to access such a inode will now error out in the verifier
rather than allowing modification operations to proceed.
Reported-by: Wen Xu <wen.xu@gatech.edu>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix a typedef, add some braces and breaks to shut up compiler warnings]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/libxfs/xfs_format.h | 3 ++
fs/xfs/libxfs/xfs_inode_buf.c | 76 ++++++++++++++++++++++-------------
2 files changed, 50 insertions(+), 29 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 1c5a8aaf2bfc..7b4a43deb83e 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -962,6 +962,9 @@ typedef enum xfs_dinode_fmt {
XFS_DFORK_DSIZE(dip, mp) : \
XFS_DFORK_ASIZE(dip, mp))
+#define XFS_DFORK_MAXEXT(dip, mp, w) \
+ (XFS_DFORK_SIZE(dip, mp, w) / sizeof(struct xfs_bmbt_rec))
+
/*
* Return pointers to the data or attribute forks.
*/
diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c
index d38d724534c4..33dc34655ac3 100644
--- a/fs/xfs/libxfs/xfs_inode_buf.c
+++ b/fs/xfs/libxfs/xfs_inode_buf.c
@@ -374,6 +374,47 @@ xfs_log_dinode_to_disk(
}
}
+static xfs_failaddr_t
+xfs_dinode_verify_fork(
+ struct xfs_dinode *dip,
+ struct xfs_mount *mp,
+ int whichfork)
+{
+ uint32_t di_nextents = XFS_DFORK_NEXTENTS(dip, whichfork);
+
+ switch (XFS_DFORK_FORMAT(dip, whichfork)) {
+ case XFS_DINODE_FMT_LOCAL:
+ /*
+ * no local regular files yet
+ */
+ if (whichfork == XFS_DATA_FORK) {
+ if (S_ISREG(be16_to_cpu(dip->di_mode)))
+ return __this_address;
+ if (be64_to_cpu(dip->di_size) >
+ XFS_DFORK_SIZE(dip, mp, whichfork))
+ return __this_address;
+ }
+ if (di_nextents)
+ return __this_address;
+ break;
+ case XFS_DINODE_FMT_EXTENTS:
+ if (di_nextents > XFS_DFORK_MAXEXT(dip, mp, whichfork))
+ return __this_address;
+ break;
+ case XFS_DINODE_FMT_BTREE:
+ if (whichfork == XFS_ATTR_FORK) {
+ if (di_nextents > MAXAEXTNUM)
+ return __this_address;
+ } else if (di_nextents > MAXEXTNUM) {
+ return __this_address;
+ }
+ break;
+ default:
+ return __this_address;
+ }
+ return NULL;
+}
+
xfs_failaddr_t
xfs_dinode_verify(
struct xfs_mount *mp,
@@ -441,24 +482,9 @@ xfs_dinode_verify(
case S_IFREG:
case S_IFLNK:
case S_IFDIR:
- switch (dip->di_format) {
- case XFS_DINODE_FMT_LOCAL:
- /*
- * no local regular files yet
- */
- if (S_ISREG(mode))
- return __this_address;
- if (di_size > XFS_DFORK_DSIZE(dip, mp))
- return __this_address;
- if (dip->di_nextents)
- return __this_address;
- /* fall through */
- case XFS_DINODE_FMT_EXTENTS:
- case XFS_DINODE_FMT_BTREE:
- break;
- default:
- return __this_address;
- }
+ fa = xfs_dinode_verify_fork(dip, mp, XFS_DATA_FORK);
+ if (fa)
+ return fa;
break;
case 0:
/* Uninitialized inode ok. */
@@ -468,17 +494,9 @@ xfs_dinode_verify(
}
if (XFS_DFORK_Q(dip)) {
- switch (dip->di_aformat) {
- case XFS_DINODE_FMT_LOCAL:
- if (dip->di_anextents)
- return __this_address;
- /* fall through */
- case XFS_DINODE_FMT_EXTENTS:
- case XFS_DINODE_FMT_BTREE:
- break;
- default:
- return __this_address;
- }
+ fa = xfs_dinode_verify_fork(dip, mp, XFS_ATTR_FORK);
+ if (fa)
+ return fa;
} else {
/*
* If there is no fork offset, this may be a freshly-made inode
--
2.17.1

43
0001-xfs-don-t-call-xfs_da_shrink_inode-with-NULL-bp.patch Normal file
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@ -0,0 +1,43 @@
From bb3d48dcf86a97dc25fe9fc2c11938e19cb4399a Mon Sep 17 00:00:00 2001
From: Eric Sandeen <sandeen@sandeen.net>
Date: Fri, 8 Jun 2018 09:53:49 -0700
Subject: [PATCH] xfs: don't call xfs_da_shrink_inode with NULL bp
xfs_attr3_leaf_create may have errored out before instantiating a buffer,
for example if the blkno is out of range. In that case there is no work
to do to remove it, and in fact xfs_da_shrink_inode will lead to an oops
if we try.
This also seems to fix a flaw where the original error from
xfs_attr3_leaf_create gets overwritten in the cleanup case, and it
removes a pointless assignment to bp which isn't used after this.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199969
Reported-by: Xu, Wen <wen.xu@gatech.edu>
Tested-by: Xu, Wen <wen.xu@gatech.edu>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/libxfs/xfs_attr_leaf.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 99e0f5749dba..76e90046731c 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -791,9 +791,8 @@ xfs_attr_shortform_to_leaf(
ASSERT(blkno == 0);
error = xfs_attr3_leaf_create(args, blkno, &bp);
if (error) {
- error = xfs_da_shrink_inode(args, 0, bp);
- bp = NULL;
- if (error)
+ /* xfs_attr3_leaf_create may not have instantiated a block */
+ if (bp && (xfs_da_shrink_inode(args, 0, bp) != 0))
goto out;
xfs_idata_realloc(dp, size, XFS_ATTR_FORK); /* try to put */
memcpy(ifp->if_u1.if_data, tmpbuffer, size); /* it back */
--
2.17.1

155
0001-xfs-validate-cached-inodes-are-free-when-allocated.patch Normal file
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@ -0,0 +1,155 @@
From afca6c5b2595fc44383919fba740c194b0b76aff Mon Sep 17 00:00:00 2001
From: Dave Chinner <dchinner@redhat.com>
Date: Tue, 17 Apr 2018 17:17:34 -0700
Subject: [PATCH] xfs: validate cached inodes are free when allocated
A recent fuzzed filesystem image cached random dcache corruption
when the reproducer was run. This often showed up as panics in
lookup_slow() on a null inode->i_ops pointer when doing pathwalks.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
....
Call Trace:
lookup_slow+0x44/0x60
walk_component+0x3dd/0x9f0
link_path_walk+0x4a7/0x830
path_lookupat+0xc1/0x470
filename_lookup+0x129/0x270
user_path_at_empty+0x36/0x40
path_listxattr+0x98/0x110
SyS_listxattr+0x13/0x20
do_syscall_64+0xf5/0x280
entry_SYSCALL_64_after_hwframe+0x42/0xb7
but had many different failure modes including deadlocks trying to
lock the inode that was just allocated or KASAN reports of
use-after-free violations.
The cause of the problem was a corrupt INOBT on a v4 fs where the
root inode was marked as free in the inobt record. Hence when we
allocated an inode, it chose the root inode to allocate, found it in
the cache and re-initialised it.
We recently fixed a similar inode allocation issue caused by inobt
record corruption problem in xfs_iget_cache_miss() in commit
ee457001ed6c ("xfs: catch inode allocation state mismatch
corruption"). This change adds similar checks to the cache-hit path
to catch it, and turns the reproducer into a corruption shutdown
situation.
Reported-by: Wen Xu <wen.xu@gatech.edu>
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix typos in comment]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/xfs_icache.c | 73 +++++++++++++++++++++++++++++----------------
1 file changed, 48 insertions(+), 25 deletions(-)
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 9a18f69f6e96..817899961f48 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -308,6 +308,46 @@ xfs_reinit_inode(
return error;
}
+/*
+ * If we are allocating a new inode, then check what was returned is
+ * actually a free, empty inode. If we are not allocating an inode,
+ * then check we didn't find a free inode.
+ *
+ * Returns:
+ * 0 if the inode free state matches the lookup context
+ * -ENOENT if the inode is free and we are not allocating
+ * -EFSCORRUPTED if there is any state mismatch at all
+ */
+static int
+xfs_iget_check_free_state(
+ struct xfs_inode *ip,
+ int flags)
+{
+ if (flags & XFS_IGET_CREATE) {
+ /* should be a free inode */
+ if (VFS_I(ip)->i_mode != 0) {
+ xfs_warn(ip->i_mount,
+"Corruption detected! Free inode 0x%llx not marked free! (mode 0x%x)",
+ ip->i_ino, VFS_I(ip)->i_mode);
+ return -EFSCORRUPTED;
+ }
+
+ if (ip->i_d.di_nblocks != 0) {
+ xfs_warn(ip->i_mount,
+"Corruption detected! Free inode 0x%llx has blocks allocated!",
+ ip->i_ino);
+ return -EFSCORRUPTED;
+ }
+ return 0;
+ }
+
+ /* should be an allocated inode */
+ if (VFS_I(ip)->i_mode == 0)
+ return -ENOENT;
+
+ return 0;
+}
+
/*
* Check the validity of the inode we just found it the cache
*/
@@ -357,12 +397,12 @@ xfs_iget_cache_hit(
}
/*
- * If lookup is racing with unlink return an error immediately.
+ * Check the inode free state is valid. This also detects lookup
+ * racing with unlinks.
*/
- if (VFS_I(ip)->i_mode == 0 && !(flags & XFS_IGET_CREATE)) {
- error = -ENOENT;
+ error = xfs_iget_check_free_state(ip, flags);
+ if (error)
goto out_error;
- }
/*
* If IRECLAIMABLE is set, we've torn down the VFS inode already.
@@ -485,29 +525,12 @@ xfs_iget_cache_miss(
/*
- * If we are allocating a new inode, then check what was returned is
- * actually a free, empty inode. If we are not allocating an inode,
- * the check we didn't find a free inode.
+ * Check the inode free state is valid. This also detects lookup
+ * racing with unlinks.
*/
- if (flags & XFS_IGET_CREATE) {
- if (VFS_I(ip)->i_mode != 0) {
- xfs_warn(mp,
-"Corruption detected! Free inode 0x%llx not marked free on disk",
- ino);
- error = -EFSCORRUPTED;
- goto out_destroy;
- }
- if (ip->i_d.di_nblocks != 0) {
- xfs_warn(mp,
-"Corruption detected! Free inode 0x%llx has blocks allocated!",
- ino);
- error = -EFSCORRUPTED;
- goto out_destroy;
- }
- } else if (VFS_I(ip)->i_mode == 0) {
- error = -ENOENT;
+ error = xfs_iget_check_free_state(ip, flags);
+ if (error)
goto out_destroy;
- }
/*
* Preload the radix tree so we can insert safely under the
--
2.17.1

86
1-2-posix-timers-Make-forward-callback-return-s64.patch Normal file
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From patchwork Tue Jun 26 13:21:31 2018
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: [1/2] posix-timers: Make forward callback return s64
From: Thomas Gleixner <tglx@linutronix.de>
X-Patchwork-Id: 10489059
Message-Id: <20180626132704.922098090@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: John Stultz <john.stultz@linaro.org>,
Peter Zijlstra <peterz@infradead.org>,
Michael Kerrisk <mtk.manpages@gmail.com>, air icy <icytxw@gmail.com>
Date: Tue, 26 Jun 2018 15:21:31 +0200
The posix timer ti_overrun handling is broken because the forwarding
functions can return a huge number of overruns which does not fit in an
int. As a consequence timer_getoverrun(2) and siginfo::si_overrun can turn
into random number generators.
As a first step to address that let the timer_forward() callbacks return
the full 64 bit value.
Cast it to (int) temporarily until k_itimer::ti_overrun is converted to
64bit and the conversion to user space visible values is sanitized.
Reported-by: air icy <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
---
kernel/time/alarmtimer.c | 4 ++--
kernel/time/posix-timers.c | 6 +++---
kernel/time/posix-timers.h | 2 +-
3 files changed, 6 insertions(+), 6 deletions(-)
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -581,11 +581,11 @@ static void alarm_timer_rearm(struct k_i
* @timr: Pointer to the posixtimer data struct
* @now: Current time to forward the timer against
*/
-static int alarm_timer_forward(struct k_itimer *timr, ktime_t now)
+static s64 alarm_timer_forward(struct k_itimer *timr, ktime_t now)
{
struct alarm *alarm = &timr->it.alarm.alarmtimer;
- return (int) alarm_forward(alarm, timr->it_interval, now);
+ return alarm_forward(alarm, timr->it_interval, now);
}
/**
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -645,11 +645,11 @@ static ktime_t common_hrtimer_remaining(
return __hrtimer_expires_remaining_adjusted(timer, now);
}
-static int common_hrtimer_forward(struct k_itimer *timr, ktime_t now)
+static s64 common_hrtimer_forward(struct k_itimer *timr, ktime_t now)
{
struct hrtimer *timer = &timr->it.real.timer;
- return (int)hrtimer_forward(timer, now, timr->it_interval);
+ return hrtimer_forward(timer, now, timr->it_interval);
}
/*
@@ -702,7 +702,7 @@ void common_timer_get(struct k_itimer *t
* expiry time forward by intervals, so expiry is > now.
*/
if (iv && (timr->it_requeue_pending & REQUEUE_PENDING || sig_none))
- timr->it_overrun += kc->timer_forward(timr, now);
+ timr->it_overrun += (int)kc->timer_forward(timr, now);
remaining = kc->timer_remaining(timr, now);
/* Return 0 only, when the timer is expired and not pending */
--- a/kernel/time/posix-timers.h
+++ b/kernel/time/posix-timers.h
@@ -19,7 +19,7 @@ struct k_clock {
void (*timer_get)(struct k_itimer *timr,
struct itimerspec64 *cur_setting);
void (*timer_rearm)(struct k_itimer *timr);
- int (*timer_forward)(struct k_itimer *timr, ktime_t now);
+ s64 (*timer_forward)(struct k_itimer *timr, ktime_t now);
ktime_t (*timer_remaining)(struct k_itimer *timr, ktime_t now);
int (*timer_try_to_cancel)(struct k_itimer *timr);
void (*timer_arm)(struct k_itimer *timr, ktime_t expires,

145
2-2-posix-timers-Sanitize-overrun-handling.patch Normal file
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@ -0,0 +1,145 @@
From patchwork Tue Jun 26 13:21:32 2018
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: [2/2] posix-timers: Sanitize overrun handling
From: Thomas Gleixner <tglx@linutronix.de>
X-Patchwork-Id: 10489053
Message-Id: <20180626132705.018623573@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: John Stultz <john.stultz@linaro.org>,
Peter Zijlstra <peterz@infradead.org>,
Michael Kerrisk <mtk.manpages@gmail.com>, air icy <icytxw@gmail.com>
Date: Tue, 26 Jun 2018 15:21:32 +0200
The posix timer overrun handling is broken because the forwarding functions
can return a huge number of overruns which does not fit in an int. As a
consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
random number generators.
The k_clock::timer_forward() callbacks return a 64 bit value now. Make
k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
accounting is correct. 3Remove the temporary (int) casts.
Add a helper function which clamps the overrun value returned to user space
via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
between 0 and INT_MAX. INT_MAX is an indicator for user space that the
overrun value has been clamped.
Reported-by: air icy <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
---
include/linux/posix-timers.h | 4 ++--
kernel/time/posix-cpu-timers.c | 2 +-
kernel/time/posix-timers.c | 31 ++++++++++++++++++++-----------
3 files changed, 23 insertions(+), 14 deletions(-)
--- a/include/linux/posix-timers.h
+++ b/include/linux/posix-timers.h
@@ -95,8 +95,8 @@ struct k_itimer {
clockid_t it_clock;
timer_t it_id;
int it_active;
- int it_overrun;
- int it_overrun_last;
+ s64 it_overrun;
+ s64 it_overrun_last;
int it_requeue_pending;
int it_sigev_notify;
ktime_t it_interval;
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -85,7 +85,7 @@ static void bump_cpu_timer(struct k_itim
continue;
timer->it.cpu.expires += incr;
- timer->it_overrun += 1 << i;
+ timer->it_overrun += 1LL << i;
delta -= incr;
}
}
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -283,6 +283,17 @@ static __init int init_posix_timers(void
}
__initcall(init_posix_timers);
+/*
+ * The siginfo si_overrun field and the return value of timer_getoverrun(2)
+ * are of type int. Clamp the overrun value to INT_MAX
+ */
+static inline int timer_overrun_to_int(struct k_itimer *timr, int baseval)
+{
+ s64 sum = timr->it_overrun_last + (s64)baseval;
+
+ return sum > (s64)INT_MAX ? INT_MAX : (int)sum;
+}
+
static void common_hrtimer_rearm(struct k_itimer *timr)
{
struct hrtimer *timer = &timr->it.real.timer;
@@ -290,9 +301,8 @@ static void common_hrtimer_rearm(struct
if (!timr->it_interval)
return;
- timr->it_overrun += (unsigned int) hrtimer_forward(timer,
- timer->base->get_time(),
- timr->it_interval);
+ timr->it_overrun += hrtimer_forward(timer, timer->base->get_time(),
+ timr->it_interval);
hrtimer_restart(timer);
}
@@ -321,10 +331,10 @@ void posixtimer_rearm(struct siginfo *in
timr->it_active = 1;
timr->it_overrun_last = timr->it_overrun;
- timr->it_overrun = -1;
+ timr->it_overrun = -1LL;
++timr->it_requeue_pending;
- info->si_overrun += timr->it_overrun_last;
+ info->si_overrun = timer_overrun_to_int(timr, info->si_overrun);
}
unlock_timer(timr, flags);
@@ -418,9 +428,8 @@ static enum hrtimer_restart posix_timer_
now = ktime_add(now, kj);
}
#endif
- timr->it_overrun += (unsigned int)
- hrtimer_forward(timer, now,
- timr->it_interval);
+ timr->it_overrun += hrtimer_forward(timer, now,
+ timr->it_interval);
ret = HRTIMER_RESTART;
++timr->it_requeue_pending;
timr->it_active = 1;
@@ -524,7 +533,7 @@ static int do_timer_create(clockid_t whi
new_timer->it_id = (timer_t) new_timer_id;
new_timer->it_clock = which_clock;
new_timer->kclock = kc;
- new_timer->it_overrun = -1;
+ new_timer->it_overrun = -1LL;
if (event) {
rcu_read_lock();
@@ -702,7 +711,7 @@ void common_timer_get(struct k_itimer *t
* expiry time forward by intervals, so expiry is > now.
*/
if (iv && (timr->it_requeue_pending & REQUEUE_PENDING || sig_none))
- timr->it_overrun += (int)kc->timer_forward(timr, now);
+ timr->it_overrun += kc->timer_forward(timr, now);
remaining = kc->timer_remaining(timr, now);
/* Return 0 only, when the timer is expired and not pending */
@@ -791,7 +800,7 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_
if (!timr)
return -EINVAL;
- overrun = timr->it_overrun_last;
+ overrun = timer_overrun_to_int(timr, 0);
unlock_timer(timr, flags);
return overrun;

50
alarmtimer-prevent-overflow-for-relative-nanosleep.patch Normal file
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@ -0,0 +1,50 @@
From 5f936e19cc0ef97dbe3a56e9498922ad5ba1edef Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Mon, 2 Jul 2018 09:34:29 +0200
Subject: alarmtimer: Prevent overflow for relative nanosleep
Air Icy reported:
UBSAN: Undefined behaviour in kernel/time/alarmtimer.c:811:7
signed integer overflow:
1529859276030040771 + 9223372036854775807 cannot be represented in type 'long long int'
Call Trace:
alarm_timer_nsleep+0x44c/0x510 kernel/time/alarmtimer.c:811
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1235 [inline]
__se_sys_clock_nanosleep kernel/time/posix-timers.c:1213 [inline]
__x64_sys_clock_nanosleep+0x326/0x4e0 kernel/time/posix-timers.c:1213
do_syscall_64+0xb8/0x3a0 arch/x86/entry/common.c:290
alarm_timer_nsleep() uses ktime_add() to add the current time and the
relative expiry value. ktime_add() has no sanity checks so the addition
can overflow when the relative timeout is large enough.
Use ktime_add_safe() which has the necessary sanity checks in place and
limits the result to the valid range.
Fixes: 9a7adcf5c6de ("timers: Posix interface for alarm-timers")
Reported-by: Team OWL337 <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1807020926360.1595@nanos.tec.linutronix.de
---
kernel/time/alarmtimer.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 78a3cc5..fa5de5e 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -808,7 +808,8 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
/* Convert (if necessary) to absolute time */
if (flags != TIMER_ABSTIME) {
ktime_t now = alarm_bases[type].gettime();
- exp = ktime_add(now, exp);
+
+ exp = ktime_add_safe(now, exp);
}
ret = alarmtimer_do_nsleep(&alarm, exp, type);
--
cgit v1.1

23
kernel.spec
View File

@ -649,6 +649,22 @@ Patch515: 0001-signal-Stop-special-casing-TRAP_FIXME-and-FPE_FIXME-.patch
# rhbz 1572944
Patch517: Revert-the-random-series-for-4.16.4.patch
# CVE-2018-13053 rhbz 1597747 1597748
Patch518: alarmtimer-prevent-overflow-for-relative-nanosleep.patch
# CVE-2018-12896 rhbz 1597759 1597760
Patch519: 1-2-posix-timers-Make-forward-callback-return-s64.patch
Patch520: 2-2-posix-timers-Sanitize-overrun-handling.patch
# CVE-2018-13093 rhbz 1597766 1597767
Patch521: 0001-xfs-validate-cached-inodes-are-free-when-allocated.patch
# CVE-2018-13094 rhbz 1597771 1597772
Patch522: 0001-xfs-don-t-call-xfs_da_shrink_inode-with-NULL-bp.patch
# CVE-2018-13095 rhbz 1597775 1597777
Patch523: 0001-xfs-More-robust-inode-extent-count-validation.patch
# END OF PATCH DEFINITIONS
%endif
@ -1898,6 +1914,13 @@ fi
#
#
%changelog
* Thu Jul 05 2018 Justin M. Forbes <jforbes@fedoraproject.org>
- Fix CVE-2018-13053 (rhbz 1597747 1597748)
- Fix CVE-2018-12896 (rhbz 1597759 1597760)
- Fix CVE-2018-13093 (rhbz 1597766 1597767)
- Fix CVE-2018-13094 (rhbz 1597771 1597772)
- Fix CVE-2018-13095 (rhbz 1597775 1597777)
* Tue Jul 03 2018 Justin M. Forbes <jforbes@fedoraproject.org> - 4.17.4-200
- Linux v4.17.4