From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
patches@lists.linux.dev, Mark Tinguely <mark.tinguely@oracle.com>,
syzbot+541dcc6ee768f77103e7@syzkaller.appspotmail.com,
Joseph Qi <joseph.qi@linux.alibaba.com>,
Mark Fasheh <mark@fasheh.com>, Joel Becker <jlbec@evilplan.org>,
Junxiao Bi <junxiao.bi@oracle.com>,
Changwei Ge <gechangwei@live.cn>, Jun Piao <piaojun@huawei.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH 6.1 27/78] ocfs2: fix recursive semaphore deadlock in fiemap call
Date: Wed, 17 Sep 2025 14:34:48 +0200 [thread overview]
Message-ID: <20250917123330.225116633@linuxfoundation.org> (raw)
In-Reply-To: <20250917123329.576087662@linuxfoundation.org>
6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mark Tinguely <mark.tinguely@oracle.com>
commit 04100f775c2ea501927f508f17ad824ad1f23c8d upstream.
syzbot detected a OCFS2 hang due to a recursive semaphore on a
FS_IOC_FIEMAP of the extent list on a specially crafted mmap file.
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142
do_page_mkwrite+0x14d/0x310 mm/memory.c:3361
wp_page_shared mm/memory.c:3762 [inline]
do_wp_page+0x268d/0x5800 mm/memory.c:3981
handle_pte_fault mm/memory.c:6068 [inline]
__handle_mm_fault+0x1033/0x5440 mm/memory.c:6195
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364
do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
RIP: 0010:raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
RIP: 0010:_inline_copy_to_user include/linux/uaccess.h:197 [inline]
RIP: 0010:_copy_to_user+0x85/0xb0 lib/usercopy.c:26
Code: e8 00 bc f7 fc 4d 39 fc 72 3d 4d 39 ec 77 38 e8 91 b9 f7 fc 4c 89
f7 89 de e8 47 25 5b fd 0f 01 cb 4c 89 ff 48 89 d9 4c 89 f6 <f3> a4 0f
1f 00 48 89 cb 0f 01 ca 48 89 d8 5b 41 5c 41 5d 41 5e 41
RSP: 0018:ffffc9000403f950 EFLAGS: 00050256
RAX: ffffffff84c7f101 RBX: 0000000000000038 RCX: 0000000000000038
RDX: 0000000000000000 RSI: ffffc9000403f9e0 RDI: 0000200000000060
RBP: ffffc9000403fa90 R08: ffffc9000403fa17 R09: 1ffff92000807f42
R10: dffffc0000000000 R11: fffff52000807f43 R12: 0000200000000098
R13: 00007ffffffff000 R14: ffffc9000403f9e0 R15: 0000200000000060
copy_to_user include/linux/uaccess.h:225 [inline]
fiemap_fill_next_extent+0x1c0/0x390 fs/ioctl.c:145
ocfs2_fiemap+0x888/0xc90 fs/ocfs2/extent_map.c:806
ioctl_fiemap fs/ioctl.c:220 [inline]
do_vfs_ioctl+0x1173/0x1430 fs/ioctl.c:532
__do_sys_ioctl fs/ioctl.c:596 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f13850fd9
RSP: 002b:00007ffe3b3518b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000200000000000 RCX: 00007f5f13850fd9
RDX: 0000200000000040 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 6165627472616568 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3b3518f0
R13: 00007ffe3b351b18 R14: 431bde82d7b634db R15: 00007f5f1389a03b
ocfs2_fiemap() takes a read lock of the ip_alloc_sem semaphore (since
v2.6.22-527-g7307de80510a) and calls fiemap_fill_next_extent() to read the
extent list of this running mmap executable. The user supplied buffer to
hold the fiemap information page faults calling ocfs2_page_mkwrite() which
will take a write lock (since v2.6.27-38-g00dc417fa3e7) of the same
semaphore. This recursive semaphore will hold filesystem locks and causes
a hang of the fileystem.
The ip_alloc_sem protects the inode extent list and size. Release the
read semphore before calling fiemap_fill_next_extent() in ocfs2_fiemap()
and ocfs2_fiemap_inline(). This does an unnecessary semaphore lock/unlock
on the last extent but simplifies the error path.
Link: https://lkml.kernel.org/r/61d1a62b-2631-4f12-81e2-cd689914360b@oracle.com
Fixes: 00dc417fa3e7 ("ocfs2: fiemap support")
Signed-off-by: Mark Tinguely <mark.tinguely@oracle.com>
Reported-by: syzbot+541dcc6ee768f77103e7@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=541dcc6ee768f77103e7
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ocfs2/extent_map.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -696,6 +696,8 @@ out:
* it not only handles the fiemap for inlined files, but also deals
* with the fast symlink, cause they have no difference for extent
* mapping per se.
+ *
+ * Must be called with ip_alloc_sem semaphore held.
*/
static int ocfs2_fiemap_inline(struct inode *inode, struct buffer_head *di_bh,
struct fiemap_extent_info *fieinfo,
@@ -707,6 +709,7 @@ static int ocfs2_fiemap_inline(struct in
u64 phys;
u32 flags = FIEMAP_EXTENT_DATA_INLINE|FIEMAP_EXTENT_LAST;
struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ lockdep_assert_held_read(&oi->ip_alloc_sem);
di = (struct ocfs2_dinode *)di_bh->b_data;
if (ocfs2_inode_is_fast_symlink(inode))
@@ -722,8 +725,11 @@ static int ocfs2_fiemap_inline(struct in
phys += offsetof(struct ocfs2_dinode,
id2.i_data.id_data);
+ /* Release the ip_alloc_sem to prevent deadlock on page fault */
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
ret = fiemap_fill_next_extent(fieinfo, 0, phys, id_count,
flags);
+ down_read(&OCFS2_I(inode)->ip_alloc_sem);
if (ret < 0)
return ret;
}
@@ -792,9 +798,11 @@ int ocfs2_fiemap(struct inode *inode, st
len_bytes = (u64)le16_to_cpu(rec.e_leaf_clusters) << osb->s_clustersize_bits;
phys_bytes = le64_to_cpu(rec.e_blkno) << osb->sb->s_blocksize_bits;
virt_bytes = (u64)le32_to_cpu(rec.e_cpos) << osb->s_clustersize_bits;
-
+ /* Release the ip_alloc_sem to prevent deadlock on page fault */
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
ret = fiemap_fill_next_extent(fieinfo, virt_bytes, phys_bytes,
len_bytes, fe_flags);
+ down_read(&OCFS2_I(inode)->ip_alloc_sem);
if (ret)
break;
next prev parent reply other threads:[~2025-09-17 13:01 UTC|newest]
Thread overview: 92+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-17 12:34 [PATCH 6.1 00/78] 6.1.153-rc1 review Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 01/78] kunit: kasan_test: disable fortify string checker on kasan_strings() test Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 02/78] mm: introduce and use {pgd,p4d}_populate_kernel() Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 03/78] media: mediatek: vcodec: Fix a resource leak related to the scp device in FW initialization Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 04/78] media: mtk-vcodec: venc: avoid -Wenum-compare-conditional warning Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 05/78] media: i2c: imx214: Fix link frequency validation Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 06/78] net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 07/78] ASoC: q6apm-dai: schedule all available frames to avoid dsp under-runs Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 08/78] tracing: Do not add length to print format in synthetic events Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 09/78] flexfiles/pNFS: fix NULL checks on result of ff_layout_choose_ds_for_read Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 10/78] NFSv4: Dont clear capabilities that wont be reset Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 11/78] NFSv4: Clear the NFS_CAP_FS_LOCATIONS flag if it is not set Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 12/78] NFSv4: Clear the NFS_CAP_XATTR flag if not supported by the server Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 13/78] tracing: Fix tracing_marker may trigger page fault during preempt_disable Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 14/78] ftrace/samples: Fix function size computation Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 15/78] NFSv4/flexfiles: Fix layout merge mirror check Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 16/78] tracing: Silence warning when chunk allocation fails in trace_pid_write Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 17/78] s390/cpum_cf: Deny all sampling events by counter PMU Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 18/78] tcp_bpf: Call sk_msg_free() when tcp_bpf_send_verdict() fails to allocate psock->cork Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 19/78] proc: fix type confusion in pde_set_flags() Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 20/78] KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 21/78] KVM: SVM: Return TSA_SQ_NO and TSA_L1_NO bits in __do_cpuid_func() Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 22/78] KVM: SVM: Set synthesized TSA CPUID flags Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 23/78] EDAC/altera: Delete an inappropriate dma_free_coherent() call Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 24/78] Revert "SUNRPC: Dont allow waiting for exiting tasks" Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 25/78] compiler-clang.h: define __SANITIZE_*__ macros only when undefined Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 26/78] mptcp: sockopt: make sync_socket_options propagate SOCK_KEEPOPEN Greg Kroah-Hartman
2025-09-17 12:34 ` Greg Kroah-Hartman [this message]
2025-09-17 12:34 ` [PATCH 6.1 28/78] net: usb: asix: ax88772: drop phylink use in PM to avoid MDIO runtime PM wakeups Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 29/78] mtd: rawnand: stm32_fmc2: avoid overlapping mappings on ECC buffer Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 30/78] mtd: rawnand: stm32_fmc2: fix ECC overwrite Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 31/78] fuse: check if copy_file_range() returns larger than requested size Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 32/78] fuse: prevent overflow in copy_file_range return value Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 33/78] libceph: fix invalid accesses to ceph_connection_v1_info Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 34/78] mm/damon/sysfs: fix use-after-free in state_show() Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 35/78] mm/damon/reclaim: avoid divide-by-zero in damon_reclaim_apply_parameters() Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 36/78] mm/damon/lru_sort: avoid divide-by-zero in damon_lru_sort_apply_parameters() Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 37/78] mtd: nand: raw: atmel: Fix comment in timings preparation Greg Kroah-Hartman
2025-09-17 12:34 ` [PATCH 6.1 38/78] mtd: nand: raw: atmel: Respect tAR, tCLR in read setup timing Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 39/78] mm/khugepaged: convert hpage_collapse_scan_pmd() to use folios Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 40/78] mm/khugepaged: fix the address passed to notifier on testing young Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 41/78] kernfs: Fix UAF in polling when open file is released Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 42/78] mm/memory-failure: fix VM_BUG_ON_PAGE(PagePoisoned(page)) when unpoison memory Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 43/78] Input: iqs7222 - avoid enabling unused interrupts Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 44/78] Input: i8042 - add TUXEDO InfinityBook Pro Gen10 AMD to i8042 quirk table Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 45/78] Revert "net: usb: asix: ax88772: drop phylink use in PM to avoid MDIO runtime PM wakeups" Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 46/78] tty: hvc_console: Call hvc_kick in hvc_write unconditionally Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 47/78] serial: sc16is7xx: fix bug in flow control levels init Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 48/78] dt-bindings: serial: brcm,bcm7271-uart: Constrain clocks Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 49/78] USB: serial: option: add Telit Cinterion FN990A w/audio compositions Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 50/78] USB: serial: option: add Telit Cinterion LE910C4-WWX new compositions Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 51/78] net: fec: Fix possible NPD in fec_enet_phy_reset_after_clk_enable() Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 52/78] tunnels: reset the GSO metadata before reusing the skb Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 53/78] docs: networking: can: change bcm_msg_head frames member to support flexible array Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 54/78] igb: fix link test skipping when interface is admin down Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 55/78] i40e: fix IRQ freeing in i40e_vsi_request_irq_msix error path Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 56/78] can: j1939: j1939_sk_bind(): call j1939_priv_put() immediately when j1939_local_ecu_get() failed Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 57/78] can: j1939: j1939_local_ecu_get(): undo increment when j1939_local_ecu_get() fails Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 58/78] can: xilinx_can: xcan_write_frame(): fix use-after-free of transmitted SKB Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 59/78] net: hsr: Disable promiscuous mode in offload mode Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 60/78] net: hsr: Add support for MC filtering at the slave device Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 61/78] net: hsr: Add VLAN CTAG filter support Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 62/78] hsr: use rtnl lock when iterating over ports Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 63/78] hsr: use hsr_for_each_port_rtnl in hsr_port_get_hsr Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 64/78] dmaengine: idxd: Fix double free in idxd_setup_wqs() Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 65/78] dmaengine: ti: edma: Fix memory allocation size for queue_priority_map Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 66/78] regulator: sy7636a: fix lifecycle of power good gpio Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 67/78] hrtimer: Remove unused function Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 68/78] hrtimer: Rename __hrtimer_hres_active() to hrtimer_hres_active() Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 69/78] hrtimers: Unconditionally update target CPU base after offline timer migration Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 70/78] USB: gadget: dummy-hcd: Fix locking bug in RT-enabled kernels Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 71/78] dmaengine: qcom: bam_dma: Fix DT error handling for num-channels/ees Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 72/78] dmaengine: dw: dmamux: Fix device reference leak in rzn1_dmamux_route_allocate Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 73/78] phy: tegra: xusb: fix device and OF node leak at probe Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 74/78] phy: ti-pipe3: fix device leak at unbind Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 75/78] drm/amdgpu: fix a memory leak in fence cleanup when unloading Greg Kroah-Hartman
2025-09-17 14:33 ` Deucher, Alexander
2025-09-17 14:45 ` Greg Kroah-Hartman
2025-09-17 19:55 ` Deucher, Alexander
2025-09-17 12:35 ` [PATCH 6.1 76/78] drm/i915/power: fix size for for_each_set_bit() in abox iteration Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 77/78] soc: qcom: mdt_loader: Fix error return values in mdt_header_valid() Greg Kroah-Hartman
2025-09-17 12:35 ` [PATCH 6.1 78/78] soc: qcom: mdt_loader: Deal with zero e_shentsize Greg Kroah-Hartman
2025-09-17 17:56 ` [PATCH 6.1 00/78] 6.1.153-rc1 review Hardik Garg
2025-09-17 20:08 ` Jon Hunter
2025-09-17 23:53 ` Peter Schneider
2025-09-18 5:18 ` Brett A C Sheffield
2025-09-18 13:06 ` [PATCH 6.1 00/78] " Ron Economos
2025-09-18 13:28 ` Anders Roxell
2025-09-19 7:19 ` Greg Kroah-Hartman
2025-09-18 17:26 ` Florian Fainelli
2025-09-18 19:19 ` Pavel Machek
2025-09-18 20:15 ` Mark Brown
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