The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 3e74859ee35edc33a022c3f3971df066ea0ca6b9
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024123045-parka-sublet-a95d@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3e74859ee35edc33a022c3f3971df066ea0ca6b9 Mon Sep 17 00:00:00 2001
From: Boris Burkov <boris(a)bur.io>
Date: Fri, 13 Dec 2024 12:22:32 -0800
Subject: [PATCH] btrfs: check folio mapping after unlock in
relocate_one_folio()
When we call btrfs_read_folio() to bring a folio uptodate, we unlock the
folio. The result of that is that a different thread can modify the
mapping (like remove it with invalidate) before we call folio_lock().
This results in an invalid page and we need to try again.
In particular, if we are relocating concurrently with aborting a
transaction, this can result in a crash like the following:
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: 0000 [#1] SMP
CPU: 76 PID: 1411631 Comm: kworker/u322:5
Workqueue: events_unbound btrfs_reclaim_bgs_work
RIP: 0010:set_page_extent_mapped+0x20/0xb0
RSP: 0018:ffffc900516a7be8 EFLAGS: 00010246
RAX: ffffea009e851d08 RBX: ffffea009e0b1880 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffc900516a7b90 RDI: ffffea009e0b1880
RBP: 0000000003573000 R08: 0000000000000001 R09: ffff88c07fd2f3f0
R10: 0000000000000000 R11: 0000194754b575be R12: 0000000003572000
R13: 0000000003572fff R14: 0000000000100cca R15: 0000000005582fff
FS: 0000000000000000(0000) GS:ffff88c07fd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000407d00f002 CR4: 00000000007706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __die+0x78/0xc0
? page_fault_oops+0x2a8/0x3a0
? __switch_to+0x133/0x530
? wq_worker_running+0xa/0x40
? exc_page_fault+0x63/0x130
? asm_exc_page_fault+0x22/0x30
? set_page_extent_mapped+0x20/0xb0
relocate_file_extent_cluster+0x1a7/0x940
relocate_data_extent+0xaf/0x120
relocate_block_group+0x20f/0x480
btrfs_relocate_block_group+0x152/0x320
btrfs_relocate_chunk+0x3d/0x120
btrfs_reclaim_bgs_work+0x2ae/0x4e0
process_scheduled_works+0x184/0x370
worker_thread+0xc6/0x3e0
? blk_add_timer+0xb0/0xb0
kthread+0xae/0xe0
? flush_tlb_kernel_range+0x90/0x90
ret_from_fork+0x2f/0x40
? flush_tlb_kernel_range+0x90/0x90
ret_from_fork_asm+0x11/0x20
</TASK>
This occurs because cleanup_one_transaction() calls
destroy_delalloc_inodes() which calls invalidate_inode_pages2() which
takes the folio_lock before setting mapping to NULL. We fail to check
this, and subsequently call set_extent_mapping(), which assumes that
mapping != NULL (in fact it asserts that in debug mode)
Note that the "fixes" patch here is not the one that introduced the
race (the very first iteration of this code from 2009) but a more recent
change that made this particular crash happen in practice.
Fixes: e7f1326cc24e ("btrfs: set page extent mapped after read_folio in relocate_one_page")
CC: stable(a)vger.kernel.org # 6.1+
Reviewed-by: Qu Wenruo <wqu(a)suse.com>
Signed-off-by: Boris Burkov <boris(a)bur.io>
Signed-off-by: David Sterba <dsterba(a)suse.com>
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index bf267bdfa8f8..db8b42f674b7 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2902,6 +2902,7 @@ static int relocate_one_folio(struct reloc_control *rc,
const bool use_rst = btrfs_need_stripe_tree_update(fs_info, rc->block_group->flags);
ASSERT(index <= last_index);
+again:
folio = filemap_lock_folio(inode->i_mapping, index);
if (IS_ERR(folio)) {
@@ -2937,6 +2938,11 @@ static int relocate_one_folio(struct reloc_control *rc,
ret = -EIO;
goto release_folio;
}
+ if (folio->mapping != inode->i_mapping) {
+ folio_unlock(folio);
+ folio_put(folio);
+ goto again;
+ }
}
/*
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 3e74859ee35edc33a022c3f3971df066ea0ca6b9
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024123042-limelight-doily-8703@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3e74859ee35edc33a022c3f3971df066ea0ca6b9 Mon Sep 17 00:00:00 2001
From: Boris Burkov <boris(a)bur.io>
Date: Fri, 13 Dec 2024 12:22:32 -0800
Subject: [PATCH] btrfs: check folio mapping after unlock in
relocate_one_folio()
When we call btrfs_read_folio() to bring a folio uptodate, we unlock the
folio. The result of that is that a different thread can modify the
mapping (like remove it with invalidate) before we call folio_lock().
This results in an invalid page and we need to try again.
In particular, if we are relocating concurrently with aborting a
transaction, this can result in a crash like the following:
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: 0000 [#1] SMP
CPU: 76 PID: 1411631 Comm: kworker/u322:5
Workqueue: events_unbound btrfs_reclaim_bgs_work
RIP: 0010:set_page_extent_mapped+0x20/0xb0
RSP: 0018:ffffc900516a7be8 EFLAGS: 00010246
RAX: ffffea009e851d08 RBX: ffffea009e0b1880 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffc900516a7b90 RDI: ffffea009e0b1880
RBP: 0000000003573000 R08: 0000000000000001 R09: ffff88c07fd2f3f0
R10: 0000000000000000 R11: 0000194754b575be R12: 0000000003572000
R13: 0000000003572fff R14: 0000000000100cca R15: 0000000005582fff
FS: 0000000000000000(0000) GS:ffff88c07fd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000407d00f002 CR4: 00000000007706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __die+0x78/0xc0
? page_fault_oops+0x2a8/0x3a0
? __switch_to+0x133/0x530
? wq_worker_running+0xa/0x40
? exc_page_fault+0x63/0x130
? asm_exc_page_fault+0x22/0x30
? set_page_extent_mapped+0x20/0xb0
relocate_file_extent_cluster+0x1a7/0x940
relocate_data_extent+0xaf/0x120
relocate_block_group+0x20f/0x480
btrfs_relocate_block_group+0x152/0x320
btrfs_relocate_chunk+0x3d/0x120
btrfs_reclaim_bgs_work+0x2ae/0x4e0
process_scheduled_works+0x184/0x370
worker_thread+0xc6/0x3e0
? blk_add_timer+0xb0/0xb0
kthread+0xae/0xe0
? flush_tlb_kernel_range+0x90/0x90
ret_from_fork+0x2f/0x40
? flush_tlb_kernel_range+0x90/0x90
ret_from_fork_asm+0x11/0x20
</TASK>
This occurs because cleanup_one_transaction() calls
destroy_delalloc_inodes() which calls invalidate_inode_pages2() which
takes the folio_lock before setting mapping to NULL. We fail to check
this, and subsequently call set_extent_mapping(), which assumes that
mapping != NULL (in fact it asserts that in debug mode)
Note that the "fixes" patch here is not the one that introduced the
race (the very first iteration of this code from 2009) but a more recent
change that made this particular crash happen in practice.
Fixes: e7f1326cc24e ("btrfs: set page extent mapped after read_folio in relocate_one_page")
CC: stable(a)vger.kernel.org # 6.1+
Reviewed-by: Qu Wenruo <wqu(a)suse.com>
Signed-off-by: Boris Burkov <boris(a)bur.io>
Signed-off-by: David Sterba <dsterba(a)suse.com>
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index bf267bdfa8f8..db8b42f674b7 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2902,6 +2902,7 @@ static int relocate_one_folio(struct reloc_control *rc,
const bool use_rst = btrfs_need_stripe_tree_update(fs_info, rc->block_group->flags);
ASSERT(index <= last_index);
+again:
folio = filemap_lock_folio(inode->i_mapping, index);
if (IS_ERR(folio)) {
@@ -2937,6 +2938,11 @@ static int relocate_one_folio(struct reloc_control *rc,
ret = -EIO;
goto release_folio;
}
+ if (folio->mapping != inode->i_mapping) {
+ folio_unlock(folio);
+ folio_put(folio);
+ goto again;
+ }
}
/*
In the page to order 0 folio conversion series, the commit
7e119cff9d0a, "ocfs2: convert w_pages to w_folios" and
commit 9a5e08652dc4b, "ocfs2: use an array of folios
instead of an array of pages", saves -ENOMEM in the
folio array upon allocation failure and calls the folio
array free code. The folio array free code expects either
valid folio pointers or NULL. Finding the -ENOMEM will
result in a panic. Fix by NULLing the error folio entry.
Signed-off-by: Mark Tinguely <mark.tinguely(a)oracle.com>
Cc: stable(a)vger.kernel.org
Cc: Changwei Ge <gechangwei(a)live.cn>
Cc: Joel Becker <jlbec(a)evilplan.org>
Cc: Junxiao Bi <junxiao.bi(a)oracle.com>
Cc: Mark Fasheh <mark(a)fasheh.com>
Cc: Matthew Wilcox <willy(a)infradead.org>
---
v2: sorry, ocfs2_grab_folios() needs the same change.
the other callers do not need the change.
---
fs/ocfs2/alloc.c | 1 +
fs/ocfs2/aops.c | 1 +
2 files changed, 2 insertions(+)
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index b8ac85b548c7..821cb7874685 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -6918,6 +6918,7 @@ static int ocfs2_grab_folios(struct inode *inode,
loff_t start, loff_t end,
if (IS_ERR(folios[numfolios])) {
ret = PTR_ERR(folios[numfolios]);
mlog_errno(ret);
+ folios[numfolios] = NULL;
goto out;
}
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 40b6bce12951..89aadc6cdd87 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -1071,6 +1071,7 @@ static int ocfs2_grab_folios_for_write(struct
address_space *mapping,
if (IS_ERR(wc->w_folios[i])) {
ret = PTR_ERR(wc->w_folios[i]);
mlog_errno(ret);
+ wc->w_folios[i] = NULL;
goto out;
}
}
--
2.39.5 (Apple Git-154)
This patch series aims to fix various issues throughout the QinHeng CH9200
driver. This driver fails to handle various failures, which in one
case has lead to a uninit access bug found via syzbot. Upon reviewing
the driver I fixed a few more issues which I have included in this patch
series.
Parts of this series are the product of discussions and suggestions I had
from others like Andrew Lunn, Simon Horman and Jakub Kicinski you can view those
discussions below:
Link: <https://lore.kernel.org/all/20250319112156.48312-1-qasdev00@gmail.com>
Link: <https://lore.kernel.org/all/20250218002443.11731-1-qasdev00@gmail.com/>
Link: <https://lore.kernel.org/all/20250311161157.49065-1-qasdev00@gmail.com/>
Qasim Ijaz (5):
fix uninitialised access bug during mii_nway_restart
remove extraneous return that prevents error propagation
fail fast on control_read() failures during get_mac_address()
add missing error handling in ch9200_bind()
avoid triggering NWay restart on non-zero PHY ID
drivers/net/usb/ch9200.c | 61 ++++++++++++++++++++++++++--------------
1 file changed, 40 insertions(+), 21 deletions(-)
--
2.39.5
Add the missing memory barrier to make sure that the REO dest ring
descriptor is read after the head pointer to avoid using stale data on
weakly ordered architectures like aarch64.
This may fix the ring-buffer corruption worked around by commit
f9fff67d2d7c ("wifi: ath11k: Fix SKB corruption in REO destination
ring") by silently discarding data, and may possibly also address user
reported errors like:
ath11k_pci 0006:01:00.0: msdu_done bit in attention is not set
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")
Cc: stable(a)vger.kernel.org # 5.6
Link: https://bugzilla.kernel.org/show_bug.cgi?id=218005
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
---
As I reported here:
https://lore.kernel.org/lkml/Z9G5zEOcTdGKm7Ei@hovoldconsulting.com/
the ath11k and ath12k appear to be missing a number of memory barriers
that are required on weakly ordered architectures like aarch64 to avoid
memory corruption issues.
Here's a fix for one more such case which people already seem to be
hitting.
Note that I've seen one "msdu_done" bit not set warning also with this
patch so whether it helps with that at all remains to be seen. I'm CCing
Jens and Steev that see these warnings frequently and that may be able
to help out with testing.
Johan
drivers/net/wireless/ath/ath11k/dp_rx.c | 25 ++++++++++++++++---------
1 file changed, 16 insertions(+), 9 deletions(-)
diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c
index 029ecf51c9ef..0a57b337e4c6 100644
--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -2646,7 +2646,7 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,
struct ath11k *ar;
struct hal_reo_dest_ring *desc;
enum hal_reo_dest_ring_push_reason push_reason;
- u32 cookie;
+ u32 cookie, info0, rx_msdu_info0, rx_mpdu_info0;
int i;
for (i = 0; i < MAX_RADIOS; i++)
@@ -2659,11 +2659,14 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,
try_again:
ath11k_hal_srng_access_begin(ab, srng);
+ /* Make sure descriptor is read after the head pointer. */
+ dma_rmb();
+
while (likely(desc =
(struct hal_reo_dest_ring *)ath11k_hal_srng_dst_get_next_entry(ab,
srng))) {
cookie = FIELD_GET(BUFFER_ADDR_INFO1_SW_COOKIE,
- desc->buf_addr_info.info1);
+ READ_ONCE(desc->buf_addr_info.info1));
buf_id = FIELD_GET(DP_RXDMA_BUF_COOKIE_BUF_ID,
cookie);
mac_id = FIELD_GET(DP_RXDMA_BUF_COOKIE_PDEV_ID, cookie);
@@ -2692,8 +2695,9 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,
num_buffs_reaped[mac_id]++;
+ info0 = READ_ONCE(desc->info0);
push_reason = FIELD_GET(HAL_REO_DEST_RING_INFO0_PUSH_REASON,
- desc->info0);
+ info0);
if (unlikely(push_reason !=
HAL_REO_DEST_RING_PUSH_REASON_ROUTING_INSTRUCTION)) {
dev_kfree_skb_any(msdu);
@@ -2701,18 +2705,21 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,
continue;
}
- rxcb->is_first_msdu = !!(desc->rx_msdu_info.info0 &
+ rx_msdu_info0 = READ_ONCE(desc->rx_msdu_info.info0);
+ rx_mpdu_info0 = READ_ONCE(desc->rx_mpdu_info.info0);
+
+ rxcb->is_first_msdu = !!(rx_msdu_info0 &
RX_MSDU_DESC_INFO0_FIRST_MSDU_IN_MPDU);
- rxcb->is_last_msdu = !!(desc->rx_msdu_info.info0 &
+ rxcb->is_last_msdu = !!(rx_msdu_info0 &
RX_MSDU_DESC_INFO0_LAST_MSDU_IN_MPDU);
- rxcb->is_continuation = !!(desc->rx_msdu_info.info0 &
+ rxcb->is_continuation = !!(rx_msdu_info0 &
RX_MSDU_DESC_INFO0_MSDU_CONTINUATION);
rxcb->peer_id = FIELD_GET(RX_MPDU_DESC_META_DATA_PEER_ID,
- desc->rx_mpdu_info.meta_data);
+ READ_ONCE(desc->rx_mpdu_info.meta_data));
rxcb->seq_no = FIELD_GET(RX_MPDU_DESC_INFO0_SEQ_NUM,
- desc->rx_mpdu_info.info0);
+ rx_mpdu_info0);
rxcb->tid = FIELD_GET(HAL_REO_DEST_RING_INFO0_RX_QUEUE_NUM,
- desc->info0);
+ info0);
rxcb->mac_id = mac_id;
__skb_queue_tail(&msdu_list[mac_id], msdu);
--
2.48.1
Users of the Lenovo ThinkPad X13s have reported that Wi-Fi sometimes
breaks and the log fills up with errors like:
ath11k_pci 0006:01:00.0: HTC Rx: insufficient length, got 1484, expected 1492
ath11k_pci 0006:01:00.0: HTC Rx: insufficient length, got 1460, expected 1484
which based on a quick look at the driver seemed to indicate some kind
of ring-buffer corruption.
Miaoqing Pan tracked it down to the host seeing the updated destination
ring head pointer before the updated descriptor, and the error handling
for that in turn leaves the ring buffer in an inconsistent state.
Add the missing memory barrier to make sure that the descriptor is read
after the head pointer to address the root cause of the corruption while
fixing up the error handling in case there are ever any (ordering) bugs
on the device side.
Note that the READ_ONCE() are only needed to avoid compiler mischief in
case the ring-buffer helpers are ever inlined.
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218623
Link: https://lore.kernel.org/20250310010217.3845141-3-quic_miaoqing@quicinc.com
Cc: Miaoqing Pan <quic_miaoqing(a)quicinc.com>
Cc: stable(a)vger.kernel.org # 5.6
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
---
drivers/net/wireless/ath/ath11k/ce.c | 11 +++++------
drivers/net/wireless/ath/ath11k/hal.c | 4 ++--
2 files changed, 7 insertions(+), 8 deletions(-)
diff --git a/drivers/net/wireless/ath/ath11k/ce.c b/drivers/net/wireless/ath/ath11k/ce.c
index e66e86bdec20..9d8efec46508 100644
--- a/drivers/net/wireless/ath/ath11k/ce.c
+++ b/drivers/net/wireless/ath/ath11k/ce.c
@@ -393,11 +393,10 @@ static int ath11k_ce_completed_recv_next(struct ath11k_ce_pipe *pipe,
goto err;
}
+ /* Make sure descriptor is read after the head pointer. */
+ dma_rmb();
+
*nbytes = ath11k_hal_ce_dst_status_get_length(desc);
- if (*nbytes == 0) {
- ret = -EIO;
- goto err;
- }
*skb = pipe->dest_ring->skb[sw_index];
pipe->dest_ring->skb[sw_index] = NULL;
@@ -430,8 +429,8 @@ static void ath11k_ce_recv_process_cb(struct ath11k_ce_pipe *pipe)
dma_unmap_single(ab->dev, ATH11K_SKB_RXCB(skb)->paddr,
max_nbytes, DMA_FROM_DEVICE);
- if (unlikely(max_nbytes < nbytes)) {
- ath11k_warn(ab, "rxed more than expected (nbytes %d, max %d)",
+ if (unlikely(max_nbytes < nbytes || nbytes == 0)) {
+ ath11k_warn(ab, "unexpected rx length (nbytes %d, max %d)",
nbytes, max_nbytes);
dev_kfree_skb_any(skb);
continue;
diff --git a/drivers/net/wireless/ath/ath11k/hal.c b/drivers/net/wireless/ath/ath11k/hal.c
index 61f4b6dd5380..8cb1505a5a0c 100644
--- a/drivers/net/wireless/ath/ath11k/hal.c
+++ b/drivers/net/wireless/ath/ath11k/hal.c
@@ -599,7 +599,7 @@ u32 ath11k_hal_ce_dst_status_get_length(void *buf)
struct hal_ce_srng_dst_status_desc *desc = buf;
u32 len;
- len = FIELD_GET(HAL_CE_DST_STATUS_DESC_FLAGS_LEN, desc->flags);
+ len = FIELD_GET(HAL_CE_DST_STATUS_DESC_FLAGS_LEN, READ_ONCE(desc->flags));
desc->flags &= ~HAL_CE_DST_STATUS_DESC_FLAGS_LEN;
return len;
@@ -829,7 +829,7 @@ void ath11k_hal_srng_access_begin(struct ath11k_base *ab, struct hal_srng *srng)
srng->u.src_ring.cached_tp =
*(volatile u32 *)srng->u.src_ring.tp_addr;
} else {
- srng->u.dst_ring.cached_hp = *srng->u.dst_ring.hp_addr;
+ srng->u.dst_ring.cached_hp = READ_ONCE(*srng->u.dst_ring.hp_addr);
/* Try to prefetch the next descriptor in the ring */
if (srng->flags & HAL_SRNG_FLAGS_CACHED)
--
2.48.1
Embryo socket is not queued in gc_candidates, so we can't drop
a reference held by its oob_skb.
Let's say we create listener and embryo sockets, send the
listener's fd to the embryo as OOB data, and close() them
without recv()ing the OOB data.
There is a self-reference cycle like
listener -> embryo.oob_skb -> listener
, so this must be cleaned up by GC. Otherwise, the listener's
refcnt is not released and sockets are leaked:
# unshare -n
# cat /proc/net/protocols | grep UNIX-STREAM
UNIX-STREAM 1024 0 -1 NI 0 yes kernel ...
# python3
>>> from array import array
>>> from socket import *
>>>
>>> s = socket(AF_UNIX, SOCK_STREAM)
>>> s.bind('\0test\0')
>>> s.listen()
>>>
>>> c = socket(AF_UNIX, SOCK_STREAM)
>>> c.connect(s.getsockname())
>>> c.sendmsg([b'x'], [(SOL_SOCKET, SCM_RIGHTS, array('i', [s.fileno()]))], MSG_OOB)
1
>>> quit()
# cat /proc/net/protocols | grep UNIX-STREAM
UNIX-STREAM 1024 3 -1 NI 0 yes kernel ...
^^^
3 sockets still in use after FDs are close()d
Let's drop the embryo socket's oob_skb ref in scan_inflight().
This also fixes a racy access to oob_skb that commit 9841991a446c
("af_unix: Update unix_sk(sk)->oob_skb under sk_receive_queue
lock.") fixed for the new Tarjan's algo-based GC.
Fixes: 314001f0bf92 ("af_unix: Add OOB support")
Reported-by: Lei Lu <llfamsec(a)gmail.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu(a)amazon.com>
---
This has no upstream commit because I replaced the entire GC in
6.10 and the new GC does not have this bug, and this fix is only
applicable to the old GC (<= 6.9), thus for 5.15/6.1/6.6.
---
---
net/unix/garbage.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index 2a758531e102..b3fbdf129944 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -102,13 +102,14 @@ static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *),
/* Process the descriptors of this socket */
int nfd = UNIXCB(skb).fp->count;
struct file **fp = UNIXCB(skb).fp->fp;
+ struct unix_sock *u;
while (nfd--) {
/* Get the socket the fd matches if it indeed does so */
struct sock *sk = unix_get_socket(*fp++);
if (sk) {
- struct unix_sock *u = unix_sk(sk);
+ u = unix_sk(sk);
/* Ignore non-candidates, they could
* have been added to the queues after
@@ -122,6 +123,13 @@ static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *),
}
}
if (hit && hitlist != NULL) {
+#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
+ u = unix_sk(x);
+ if (u->oob_skb) {
+ WARN_ON_ONCE(skb_unref(u->oob_skb));
+ u->oob_skb = NULL;
+ }
+#endif
__skb_unlink(skb, &x->sk_receive_queue);
__skb_queue_tail(hitlist, skb);
}
@@ -299,17 +307,9 @@ void unix_gc(void)
* which are creating the cycle(s).
*/
skb_queue_head_init(&hitlist);
- list_for_each_entry(u, &gc_candidates, link) {
+ list_for_each_entry(u, &gc_candidates, link)
scan_children(&u->sk, inc_inflight, &hitlist);
-#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
- if (u->oob_skb) {
- kfree_skb(u->oob_skb);
- u->oob_skb = NULL;
- }
-#endif
- }
-
/* not_cycle_list contains those sockets which do not make up a
* cycle. Restore these to the inflight list.
*/
--
2.39.5 (Apple Git-154)