[rocky8_10] History Rebuild through kernel-4.18.0-553.157.1.el8_10 - #1548
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[rocky8_10] History Rebuild through kernel-4.18.0-553.157.1.el8_10#1548PlaidCat wants to merge 13 commits into
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jira KERNEL-1512 cve CVE-2026-46120 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Maoyi Xie <maoyixie.tju@gmail.com> commit 1d324c2 After commit 5e72ce3 ("net: ipv6: Use link netns in newlink() of rtnl_link_ops"), ip6erspan_newlink() correctly resolves the per-netns ip6gre hash via link_net. ip6erspan_changelink() was not converted in that series and still uses dev_net(dev), which diverges from the device's creation netns after IFLA_NET_NS_FD migration. This re-inserts the tunnel into the wrong per-netns hash. The original netns keeps a stale entry. When that netns is later destroyed, ip6gre_exit_rtnl_net() walks the stale entry, producing a slab-use-after-free reported by KASAN, followed by a kernel BUG at net/core/dev.c (LIST_POISON1) in unregister_netdevice_many_notify(). Reachable from an unprivileged user namespace (unshare --user --map-root-user --net). ip6gre_changelink() earlier in the same file already uses the cached t->net; only ip6erspan_changelink() has the wrong shape. Fixes: 2d66503 ("net: ip6_gre: Fix ip6erspan hlen calculation") Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Maoyi Xie <maoyi.xie@ntu.edu.sg> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260430103318.3206018-1-maoyi.xie@ntu.edu.sg Signed-off-by: Jakub Kicinski <kuba@kernel.org> (cherry picked from commit 1d324c2) Signed-off-by: Jonathan Maple <jmaple@ciq.com>
jira KERNEL-1512 cve CVE-2026-63887 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Michael Bommarito <michael.bommarito@gmail.com> commit bf33e01 iscsi_encode_text_output() concatenates "key=value\0" records into login->rsp_buf, an 8192-byte kzalloc(MAX_KEY_VALUE_PAIRS) buffer allocated in iscsit_alloc_login_setup_buffer(). The three sprintf() call sites in this function (lines 1398, 1411, 1424 in v7.1-rc2) never check the remaining buffer capacity: *length += sprintf(output_buf, "%s=%s", er->key, er->value); *length += 1; output_buf = textbuf + *length; The 8192-byte ceiling at iscsi_target_check_login_request() bounds the *input* Login PDU payload, but a single PDU can carry up to 2048 minimal four-byte "a=b\0" pairs, each unknown key expanding to a 16-byte "a=NotUnderstood\0" output record via iscsi_add_notunderstood_response(). 2048 * 16 = 32 KiB of output into an 8 KiB buffer, producing a ~24 KiB heap overrun in the kmalloc-8k slab. The fix introduces a static iscsi_encode_text_record() helper that uses snprintf() with a per-call bounds check against the remaining buffer, and threads a u32 textbuf_size parameter through iscsi_encode_text_output(). Both call sites in iscsi_target_handle_csg_zero() (PHASE_SECURITY) and iscsi_target_handle_csg_one() (PHASE_OPERATIONAL) pass MAX_KEY_VALUE_PAIRS. On overflow the encoder logs the condition, calls iscsi_release_extra_responses() to drop queued records, and returns -1; both caller sites now emit ISCSI_STATUS_CLS_INITIATOR_ERR / ISCSI_LOGIN_STATUS_INIT_ERR via iscsit_tx_login_rsp() before returning, so the initiator sees an explicit failed-login response rather than a silent connection drop. (Prior to this patch only the PHASE_OPERATIONAL caller did that; the PHASE_SECURITY caller is converted to the same shape.) Fixes: e48354c ("iscsi-target: Add iSCSI fabric support for target v4.1") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Tested-by: John Garry <john.g.garry@oracle.com> Reviewed-by: John Garry <john.g.garry@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> (cherry picked from commit bf33e01) Signed-off-by: Jonathan Maple <jmaple@ciq.com>
jira KERNEL-1512 cve CVE-2026-64048 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Xiang Mei <xmei5@asu.edu> commit 2777400 On the SMC-D client, slot 0 of ini->ism_dev[]/ini->ism_chid[] is reserved for an SMC-Dv1 device. smc_find_ism_v2_device_clnt() populates V2 entries starting at index 1, so when no V1 device is selected slot 0 is left in its kzalloc()'ed state with ism_dev[0] == NULL and ism_chid[0] == 0. smc_v2_determine_accepted_chid() then matches the peer's CHID against the array starting from index 0 using the CHID alone. A malicious peer replying to a SMC-Dv2-only proposal with d1.chid == 0 matches the empty slot, ini->ism_selected becomes 0, and the subsequent ism_dev[0]->lgr_lock dereference in smc_conn_create() faults at offsetof(struct smcd_dev, lgr_lock) == 0x68: BUG: KASAN: null-ptr-deref in _raw_spin_lock_bh+0x79/0xe0 Write of size 4 at addr 0000000000000068 by task exploit/144 Call Trace: _raw_spin_lock_bh smc_conn_create (net/smc/smc_core.c:1997) __smc_connect (net/smc/af_smc.c:1447) smc_connect (net/smc/af_smc.c:1720) __sys_connect __x64_sys_connect do_syscall_64 Require ism_dev[i] to be non-NULL before accepting a CHID match. Fixes: a7c9c5f ("net/smc: CLC accept / confirm V2") Reported-by: Weiming Shi <bestswngs@gmail.com> Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Xiang Mei <xmei5@asu.edu> Link: https://patch.msgid.link/20260511062138.2839584-1-xmei5@asu.edu Signed-off-by: Paolo Abeni <pabeni@redhat.com> (cherry picked from commit 2777400) Signed-off-by: Jonathan Maple <jmaple@ciq.com>
jira KERNEL-1512 cve CVE-2026-53189 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Yin Tirui <yintirui@huawei.com> commit 8d87805 Empty-Commit: Cherry-Pick Conflicts during history rebuild. Will be included in final tarball splat. Ref for failed cherry-pick at: ciq/ciq_backports/kernel-4.18.0-553.157.1.el8_10/8d878059.failed __split_huge_pmd_locked() updates the file/shmem RSS counter after dropping the PMD mapping's folio reference. If folio_put() drops the last reference, mm_counter_file() can later read freed folio state via folio_test_swapbacked(). Move the counter update before folio_put(). Link: https://lore.kernel.org/20260526101337.1984081-1-yintirui@huawei.com Fixes: fadae29 ("thp: use mm_file_counter to determine update which rss counter") Signed-off-by: Yin Tirui <yintirui@huawei.com> Reviewed-by: Lorenzo Stoakes <ljs@kernel.org> Acked-by: David Hildenbrand (arm) <david@kernel.org> Reviewed-by: Lance Yang <lance.yang@linux.dev> Reviewed-by: Dev Jain <dev.jain@arm.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Chen Jun <chenjun102@huawei.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Liam R. Howlett <liam@infradead.org> Cc: Nico Pache <npache@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Yang Shi <yang.shi@linux.alibaba.com> Cc: Zi Yan <ziy@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> (cherry picked from commit 8d87805) Signed-off-by: Jonathan Maple <jmaple@ciq.com> # Conflicts: # mm/huge_memory.c
jira KERNEL-1512 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Suren Baghdasaryan <surenb@google.com> commit 51e50fb When CONFIG_CGROUPS is disabled psi code generates the following warnings: kernel/sched/psi.c:1112:21: warning: no previous prototype for 'psi_trigger_create' [-Wmissing-prototypes] 1112 | struct psi_trigger *psi_trigger_create(struct psi_group *group, | ^~~~~~~~~~~~~~~~~~ kernel/sched/psi.c:1182:6: warning: no previous prototype for 'psi_trigger_destroy' [-Wmissing-prototypes] 1182 | void psi_trigger_destroy(struct psi_trigger *t) | ^~~~~~~~~~~~~~~~~~~ kernel/sched/psi.c:1249:10: warning: no previous prototype for 'psi_trigger_poll' [-Wmissing-prototypes] 1249 | __poll_t psi_trigger_poll(void **trigger_ptr, | ^~~~~~~~~~~~~~~~ Change the declarations of these functions in the header to provide the prototypes even when they are unused. Link: https://lkml.kernel.org/r/20220119223940.787748-2-surenb@google.com Fixes: 0e94682 ("psi: introduce psi monitor") Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> (cherry picked from commit 51e50fb) Signed-off-by: Jonathan Maple <jmaple@ciq.com>
jira KERNEL-1512 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Hao Jia <jiahao.os@bytedance.com> commit 76b079e Empty-Commit: Cherry-Pick Conflicts during history rebuild. Will be included in final tarball splat. Ref for failed cherry-pick at: ciq/ciq_backports/kernel-4.18.0-553.157.1.el8_10/76b079ef.failed psi_trigger_create()'s 'nbytes' parameter is not used, so we can remove it. Signed-off-by: Hao Jia <jiahao.os@bytedance.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Tejun Heo <tj@kernel.org> (cherry picked from commit 76b079e) Signed-off-by: Jonathan Maple <jmaple@ciq.com> # Conflicts: # kernel/cgroup/cgroup.c
jira KERNEL-1512 cve CVE-2026-52991 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Edward Adam Davis <eadavis@qq.com> commit a5b9800 Empty-Commit: Cherry-Pick Conflicts during history rebuild. Will be included in final tarball splat. Ref for failed cherry-pick at: ciq/ciq_backports/kernel-4.18.0-553.157.1.el8_10/a5b98009.failed A potential race condition exists between pressure write and cgroup file release regarding the priv member of struct kernfs_open_file, which triggers the uaf reported in [1]. Consider the following scenario involving execution on two separate CPUs: CPU0 CPU1 ==== ==== vfs_rmdir() kernfs_iop_rmdir() cgroup_rmdir() cgroup_kn_lock_live() cgroup_destroy_locked() cgroup_addrm_files() cgroup_rm_file() kernfs_remove_by_name() kernfs_remove_by_name_ns() vfs_write() __kernfs_remove() new_sync_write() kernfs_drain() kernfs_fop_write_iter() kernfs_drain_open_files() cgroup_file_write() kernfs_release_file() pressure_write() cgroup_file_release() ctx = of->priv; kfree(ctx); of->priv = NULL; cgroup_kn_unlock() cgroup_kn_lock_live() cgroup_get(cgrp) cgroup_kn_unlock() if (ctx->psi.trigger) // here, trigger uaf for ctx, that is of->priv The cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards the memory deallocation of of->priv performed within cgroup_file_release(). However, the operations involving of->priv executed within pressure_write() are not entirely covered by the protection of cgroup_mutex. Consequently, if the code in pressure_write(), specifically the section handling the ctx variable executes after cgroup_file_release() has completed, a uaf vulnerability involving of->priv is triggered. Therefore, the issue can be resolved by extending the scope of the cgroup_mutex lock within pressure_write() to encompass all code paths involving of->priv, thereby properly synchronizing the race condition occurring between cgroup_file_release() and pressure_write(). And, if an live kn lock can be successfully acquired while executing the pressure write operation, it indicates that the cgroup deletion process has not yet reached its final stage; consequently, the priv pointer within open_file cannot be NULL. Therefore, the operation to retrieve the ctx value must be moved to a point *after* the live kn lock has been successfully acquired. In another situation, specifically after entering cgroup_kn_lock_live() but before acquiring cgroup_mutex, there exists a different class of race condition: CPU0: write memory.pressure CPU1: write cgroup.pressure=0 =========================== ============================= kernfs_fop_write_iter() kernfs_get_active_of(of) pressure_write() cgroup_kn_lock_live(memory.pressure) cgroup_tryget(cgrp) kernfs_break_active_protection(kn) ... blocks on cgroup_mutex cgroup_pressure_write() cgroup_kn_lock_live(cgroup.pressure) cgroup_file_show(memory.pressure, false) kernfs_show(false) kernfs_drain_open_files() cgroup_file_release(of) kfree(ctx) of->priv = NULL cgroup_kn_unlock() ... acquires cgroup_mutex ctx = of->priv; // may now be NULL if (ctx->psi.trigger) // NULL dereference Consequently, there is a possibility that of->priv is NULL, the pressure write needs to check for this. Now that the scope of the cgroup_mutex has been expanded, the original explicit cgroup_get/put operations are no longer necessary, this is because acquiring/releasing the live kn lock inherently executes a cgroup get/put operation. [1] BUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011 Call Trace: pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011 cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:4311 kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352 Allocated by task 9352: cgroup_file_open+0x90/0x3a0 kernel/cgroup/cgroup.c:4256 kernfs_fop_open+0x9eb/0xcb0 fs/kernfs/file.c:724 do_dentry_open+0x83d/0x13e0 fs/open.c:949 Freed by task 9353: cgroup_file_release+0xd6/0x100 kernel/cgroup/cgroup.c:4283 kernfs_release_file fs/kernfs/file.c:764 [inline] kernfs_drain_open_files+0x392/0x720 fs/kernfs/file.c:834 kernfs_drain+0x470/0x600 fs/kernfs/dir.c:525 Fixes: 0e94682 ("psi: introduce psi monitor") Reported-by: syzbot+33e571025d88efd1312c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=33e571025d88efd1312c Tested-by: syzbot+33e571025d88efd1312c@syzkaller.appspotmail.com Signed-off-by: Edward Adam Davis <eadavis@qq.com> Reviewed-by: Chen Ridong <chenridong@huaweicloud.com> Signed-off-by: Tejun Heo <tj@kernel.org> (cherry picked from commit a5b9800) Signed-off-by: Jonathan Maple <jmaple@ciq.com> # Conflicts: # kernel/cgroup/cgroup.c
jira KERNEL-1512 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Chen Ridong <chenridong@huawei.com> commit 94a4acf Setting of->priv to NULL when the file is released enables earlier bug detection. This allows potential bugs to manifest as NULL pointer dereferences rather than use-after-free errors[1], which are generally more difficult to diagnose. [1] https://lore.kernel.org/cgroups/38ef3ff9-b380-44f0-9315-8b3714b0948d@huaweicloud.com/T/#m8a3b3f88f0ff3da5925d342e90043394f8b2091b Signed-off-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> (cherry picked from commit 94a4acf) Signed-off-by: Jonathan Maple <jmaple@ciq.com>
…ate() jira KERNEL-1512 cve CVE-2024-56602 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Ignat Korchagin <ignat@cloudflare.com> commit b4fcd63 sock_init_data() attaches the allocated sk object to the provided sock object. If ieee802154_create() fails later, the allocated sk object is freed, but the dangling pointer remains in the provided sock object, which may allow use-after-free. Clear the sk pointer in the sock object on error. Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241014153808.51894-6-ignat@cloudflare.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> (cherry picked from commit b4fcd63) Signed-off-by: Jonathan Maple <jmaple@ciq.com>
…e_text_cmd() jira KERNEL-1512 cve CVE-2026-63888 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Michael Bommarito <michael.bommarito@gmail.com> commit 778c2ab Empty-Commit: Cherry-Pick Conflicts during history rebuild. Will be included in final tarball splat. Ref for failed cherry-pick at: ciq/ciq_backports/kernel-4.18.0-553.157.1.el8_10/778c2ab1.failed Two latent bugs in the Text-phase handler, both present since the original LIO integration in commit e48354c ("iscsi-target: Add iSCSI fabric support for target v4.1"): 1) DataDigest CRC buffer overread (4 bytes past text_in). text_in is kzalloc()'d at ALIGN(payload_length, 4). rx_size is then incremented by ISCSI_CRC_LEN to make room for the received DataDigest in the iovec, but the same (now-bumped) rx_size is passed as the buffer length to iscsit_crc_buf(): if (conn->conn_ops->DataDigest) { ... rx_size += ISCSI_CRC_LEN; } ... if (conn->conn_ops->DataDigest) { data_crc = iscsit_crc_buf(text_in, rx_size, 0, NULL); iscsit_crc_buf() walks rx_size bytes of text_in with crc32c(), so when DataDigest is negotiated it reads 4 bytes past the end of the text_in allocation. KASAN reproduces this directly on the unpatched mainline tree as slab-out-of-bounds in crc32c() called from the Text PDU path. The OOB bytes feed crc32c() and are then compared against the initiator-supplied checksum, so the value does not flow back to the attacker, but the kernel does read past the buffer on every Text PDU with DataDigest=CRC32C. Fix by passing the actual padded payload length (ALIGN(payload_length, 4)) that was used for the kzalloc(). 2) Stale cmd->text_in_ptr re-free (double-free) on ERL>0 bad DataDigest drop. On DataDigest mismatch with ErrorRecoveryLevel > 0 the handler silently drops the PDU and lets the initiator plug the CmdSN gap: kfree(text_in); return 0; cmd->text_in_ptr still points at the freed buffer. The next Text Request on the same ITT re-enters iscsit_setup_text_cmd(), which unconditionally does kfree(cmd->text_in_ptr); cmd->text_in_ptr = NULL; freeing the same pointer a second time. Session teardown via iscsit_release_cmd() has the same shape and hits the same double-free if the connection is dropped before a second Text Request arrives. On an unmodified mainline tree the bug-1 CRC overread fires first on the initial valid Text Request and perturbs the subsequent state, so #4 was isolated by building a kernel with only the bug-1 hunk of this patch applied plus temporary printk() observability around the three relevant kfree() sites. The observability prints are not part of this patch. On that build, a three-PDU Text Request sequence after login produces two back-to-back splats: BUG: KASAN: double-free in iscsit_setup_text_cmd+0x?? BUG: KASAN: double-free in iscsit_release_cmd+0x?? showing the same pointer freed in the ERL>0 drop path and again in iscsit_setup_text_cmd() (next Text Request on the same ITT) and once more in iscsit_release_cmd() (session teardown). On distro kernels with CONFIG_SLAB_FREELIST_HARDENED=y (default) the double-free becomes a remote kernel BUG(); on non-hardened kernels it corrupts the slab freelist. Fix by clearing cmd->text_in_ptr after the kfree() in the ERL>0 drop path. With both hunks applied #4 is directly observable on the stock tree without observability printks; fixing bug-1 alone would mask #4 less, not more, so the hunks are submitted together. Both fixes are one-liners. The Text PDU state machine is unchanged and the wire protocol is unaffected. Fixes: e48354c ("iscsi-target: Add iSCSI fabric support for target v4.1") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Tested-by: John Garry <john.g.garry@oracle.com> Reviewed-by: John Garry <john.g.garry@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> (cherry picked from commit 778c2ab) Signed-off-by: Jonathan Maple <jmaple@ciq.com> # Conflicts: # drivers/target/iscsi/iscsi_target.c
jira KERNEL-1512 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Charan Teja Reddy <charante@codeaurora.org> commit aa09259 Updating the zone watermarks by any means, like min_free_kbytes, water_mark_scale_factor etc, when ->watermark_boost is set will result in higher low and high watermarks than the user asked. Below are the steps to reproduce the problem on system setup of Android kernel running on Snapdragon hardware. 1) Default settings of the system are as below: #cat /proc/sys/vm/min_free_kbytes = 5162 #cat /proc/zoneinfo | grep -e boost -e low -e "high " -e min -e Node Node 0, zone Normal min 797 low 8340 high 8539 2) Monitor the zone->watermark_boost(by adding a debug print in the kernel) and whenever it is greater than zero value, write the same value of min_free_kbytes obtained from step 1. #echo 5162 > /proc/sys/vm/min_free_kbytes 3) Then read the zone watermarks in the system while the ->watermark_boost is zero. This should show the same values of watermarks as step 1 but shown a higher values than asked. #cat /proc/zoneinfo | grep -e boost -e low -e "high " -e min -e Node Node 0, zone Normal min 797 low 21148 high 21347 These higher values are because of updating the zone watermarks using the macro min_wmark_pages(zone) which also adds the zone->watermark_boost. #define min_wmark_pages(z) (z->_watermark[WMARK_MIN] + z->watermark_boost) So the steps that lead to the issue are: 1) On the extfrag event, watermarks are boosted by storing the required value in ->watermark_boost. 2) User tries to update the zone watermarks level in the system through min_free_kbytes or watermark_scale_factor. 3) Later, when kswapd woke up, it resets the zone->watermark_boost to zero. In step 2), we use the min_wmark_pages() macro to store the watermarks in the zone structure thus the values are always offsetted by ->watermark_boost value. This can be avoided by resetting the ->watermark_boost to zero before it is used. Signed-off-by: Charan Teja Reddy <charante@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: Vinayak Menon <vinmenon@codeaurora.org> Link: http://lkml.kernel.org/r/1589457511-4255-1-git-send-email-charante@codeaurora.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> (cherry picked from commit aa09259) Signed-off-by: Jonathan Maple <jmaple@ciq.com>
jira KERNEL-1512 Rebuild_History Non-Buildable kernel-4.18.0-553.157.1.el8_10 commit-author Charan Teja Reddy <charante@codeaurora.org> commit f80b08f When boosting is enabled, it is observed that rate of atomic order-0 allocation failures are high due to the fact that free levels in the system are checked with ->watermark_boost offset. This is not a problem for sleepable allocations but for atomic allocations which looks like regression. This problem is seen frequently on system setup of Android kernel running on Snapdragon hardware with 4GB RAM size. When no extfrag event occurred in the system, ->watermark_boost factor is zero, thus the watermark configurations in the system are: _watermark = ( [WMARK_MIN] = 1272, --> ~5MB [WMARK_LOW] = 9067, --> ~36MB [WMARK_HIGH] = 9385), --> ~38MB watermark_boost = 0 After launching some memory hungry applications in Android which can cause extfrag events in the system to an extent that ->watermark_boost can be set to max i.e. default boost factor makes it to 150% of high watermark. _watermark = ( [WMARK_MIN] = 1272, --> ~5MB [WMARK_LOW] = 9067, --> ~36MB [WMARK_HIGH] = 9385), --> ~38MB watermark_boost = 14077, -->~57MB With default system configuration, for an atomic order-0 allocation to succeed, having free memory of ~2MB will suffice. But boosting makes the min_wmark to ~61MB thus for an atomic order-0 allocation to be successful system should have minimum of ~23MB of free memory(from calculations of zone_watermark_ok(), min = 3/4(min/2)). But failures are observed despite system is having ~20MB of free memory. In the testing, this is reproducible as early as first 300secs since boot and with furtherlowram configurations(<2GB) it is observed as early as first 150secs since boot. These failures can be avoided by excluding the ->watermark_boost in watermark caluculations for atomic order-0 allocations. [akpm@linux-foundation.org: fix comment grammar, reflow comment] [charante@codeaurora.org: fix suggested by Mel Gorman] Link: http://lkml.kernel.org/r/31556793-57b1-1c21-1a9d-22674d9bd938@codeaurora.org Signed-off-by: Charan Teja Reddy <charante@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Vinayak Menon <vinmenon@codeaurora.org> Cc: Mel Gorman <mgorman@techsingularity.net> Link: http://lkml.kernel.org/r/1589882284-21010-1-git-send-email-charante@codeaurora.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> (cherry picked from commit f80b08f) Signed-off-by: Jonathan Maple <jmaple@ciq.com>
Rebuild_History BUILDABLE Rebuilding Kernel from rpm changelog with Fuzz Limit: 87.50% Number of commits in upstream range v4.18~1..kernel-mainline: 625874 Number of commits in rpm: 21 Number of commits matched with upstream: 12 (57.14%) Number of commits in upstream but not in rpm: 625862 Number of commits NOT found in upstream: 9 (42.86%) Rebuilding Kernel on Branch rocky8_10_rebuild_kernel-4.18.0-553.157.1.el8_10 for kernel-4.18.0-553.157.1.el8_10 Clean Cherry Picks: 8 (66.67%) Empty Cherry Picks: 4 (33.33%) _______________________________ Full Details Located here: ciq/ciq_backports/kernel-4.18.0-553.157.1.el8_10/rebuild.details.txt Includes: * git commit header above * Empty Commits with upstream SHA * RPM ChangeLog Entries that could not be matched Individual Empty Commit failures contained in the same containing directory. The git message for empty commits will have the path for the failed commit. File names are the first 8 characters of the upstream SHA
bmastbergen
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Approved for correct content. It does look like the three commits marked as not in upstream are in fact in upstream. Weird.
shreeya-patel98
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Aug 21, 2026
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This is an automated kernel history rebuild using cron and internal tooling. It follows the same process used for previous history rebuilds:
src.rpmpackagessrc.rpm:4.18.0-553)git cherry-pickrpmbuild -bpfor the correspondingsrc.rpmJIRA Tickets
Rebuild Splat Inspection
kernel-4.18.0-553.157.1.el8_10
BUILD
KSelfTests