Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: iommu: Clear iommu-dma ops on cleanup If iommu_device_register() encounters an error, it can end up tearing down already-configured groups and default domains, however this currently still leaves devices hooked up to iommu-dma (and even historically the behaviour in this area was at best inconsistent across architectures/drivers...) Although in the case that an IOMMU is present whose driver has failed to probe, users cannot necessarily expect DMA to work anyway, it's still arguable that we should do our best to put things back as if the IOMMU driver was never there at all, and certainly the potential for crashing in iommu-dma itself is undesirable. Make sure we clean up the dev->dma_iommu flag along with everything else.Show less

In the Linux kernel, the following vulnerability has been resolved: netfs: Only create /proc/fs/netfs with CONFIG_PROC_FS When testing a special config: CONFIG_NETFS_SUPPORTS=y CONFIG_PROC_FS=n The system crashes with something like: [ 3.766197] ------------[ cut here ]------------ [ 3.766484] kernel BUG at mm/mempool.c:560! [ 3.766789] Oops: invalid opcode: 0000 [#1] SMP NOPTI [ 3.767123] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G W [ 3.767777] Tainted: [W]=WARN [ 3.767968] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), [ 3.768523] RIP: 0010:mempool_alloc_slab.cold+0x17/0x19 [ 3.768847] Code: 50 fe ff 58 5b 5d 41 5c 41 5d 41 5e 41 5f e9 93 95 13 00 [ 3.769977] RSP: 0018:ffffc90000013998 EFLAGS: 00010286 [ 3.770315] RAX: 000000000000002f RBX: ffff888100ba8640 RCX: 0000000000000000 [ 3.770749] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 00000000ffffffff [ 3.771217] RBP: 0000000000092880 R08: 0000000000000000 R09: ffffc90000013828 [ 3.771664] R10: 0000000000000001 R11: 00000000ffffffea R12: 0000000000092cc0 [ 3.772117] R13: 0000000000000400 R14: ffff8881004b1620 R15: ffffea0004ef7e40 [ 3.772554] FS: 0000000000000000(0000) GS:ffff8881b5f3c000(0000) knlGS:0000000000000000 [ 3.773061] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.773443] CR2: ffffffff830901b4 CR3: 0000000004296001 CR4: 0000000000770ef0 [ 3.773884] PKRU: 55555554 [ 3.774058] Call Trace: [ 3.774232] <TASK> [ 3.774371] mempool_alloc_noprof+0x6a/0x190 [ 3.774649] ? _printk+0x57/0x80 [ 3.774862] netfs_alloc_request+0x85/0x2ce [ 3.775147] netfs_readahead+0x28/0x170 [ 3.775395] read_pages+0x6c/0x350 [ 3.775623] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.775928] page_cache_ra_unbounded+0x1bd/0x2a0 [ 3.776247] filemap_get_pages+0x139/0x970 [ 3.776510] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.776820] filemap_read+0xf9/0x580 [ 3.777054] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.777368] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.777674] ? find_held_lock+0x32/0x90 [ 3.777929] ? netfs_start_io_read+0x19/0x70 [ 3.778221] ? netfs_start_io_read+0x19/0x70 [ 3.778489] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.778800] ? lock_acquired+0x1e6/0x450 [ 3.779054] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.779379] netfs_buffered_read_iter+0x57/0x80 [ 3.779670] __kernel_read+0x158/0x2c0 [ 3.779927] bprm_execve+0x300/0x7a0 [ 3.780185] kernel_execve+0x10c/0x140 [ 3.780423] ? __pfx_kernel_init+0x10/0x10 [ 3.780690] kernel_init+0xd5/0x150 [ 3.780910] ret_from_fork+0x2d/0x50 [ 3.781156] ? __pfx_kernel_init+0x10/0x10 [ 3.781414] ret_from_fork_asm+0x1a/0x30 [ 3.781677] </TASK> [ 3.781823] Modules linked in: [ 3.782065] ---[ end trace 0000000000000000 ]--- This is caused by the following error path in netfs_init(): if (!proc_mkdir("fs/netfs", NULL)) goto error_proc; Fix this by adding ifdef in netfs_main(), so that /proc/fs/netfs is only created with CONFIG_PROC_FS.Show less

In the Linux kernel, the following vulnerability has been resolved: igc: fix PTM cycle trigger logic Writing to clear the PTM status 'valid' bit while the PTM cycle is triggered results in unreliable PTM operation. To fix this, clear the PTM 'trigger' and status after each PTM transaction. The issue can be reproduced with the following: $ sudo phc2sys -R 1000 -O 0 -i tsn0 -m Note: 1000 Hz (-R 1000) is unrealistically large, but provides a way to quickly reproduce the issue. PHC2SYS exits with: "ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction fails This patch also fixes a hang in igc_probe() when loading the igc driver in the kdump kernel on systems supporting PTM. The igc driver running in the base kernel enables PTM trigger in igc_probe(). Therefore the driver is always in PTM trigger mode, except in brief periods when manually triggering a PTM cycle. When a crash occurs, the NIC is reset while PTM trigger is enabled. Due to a hardware problem, the NIC is subsequently in a bad busmaster state and doesn't handle register reads/writes. When running igc_probe() in the kdump kernel, the first register access to a NIC register hangs driver probing and ultimately breaks kdump. With this patch, igc has PTM trigger disabled most of the time, and the trigger is only enabled for very brief (10 - 100 us) periods when manually triggering a PTM cycle. Chances that a crash occurs during a PTM trigger are not 0, but extremely reduced.Show less

In the Linux kernel, the following vulnerability has been resolved: net: ngbe: fix memory leak in ngbe_probe() error path When ngbe_sw_init() is called, memory is allocated for wx->rss_key in wx_init_rss_key(). However, in ngbe_probe() function, the subsequent error paths after ngbe_sw_init() don't free the rss_key. Fix that by freeing it in error path along with wx->mac_table. Also change the label to which execution jumps when ngbe_sw_init() fails, because otherwise, it could lead to a double free for rss_key, when the mac_table allocation fails in wx_sw_init().Show less

In the Linux kernel, the following vulnerability has been resolved: eth: bnxt: fix missing ring index trim on error path Commit under Fixes converted tx_prod to be free running but missed masking it on the Tx error path. This crashes on error conditions, for example when DMA mapping fails.Show less

In the Linux kernel, the following vulnerability has been resolved: net: txgbe: fix memory leak in txgbe_probe() error path When txgbe_sw_init() is called, memory is allocated for wx->rss_key in wx_init_rss_key(). However, in txgbe_probe() function, the subsequent error paths after txgbe_sw_init() don't free the rss_key. Fix that by freeing it in error path along with wx->mac_table. Also change the label to which execution jumps when txgbe_sw_init() fails, because otherwise, it could lead to a double free for rss_key, when the mac_table allocation fails in wx_sw_init().Show less

In the Linux kernel, the following vulnerability has been resolved: nfsd: decrease sc_count directly if fail to queue dl_recall A deadlock warning occurred when invoking nfs4_put_stid following a failed dl_recall queue operation: T1 T2 nfs4_laundromat nfs4_get_client_reaplist nfs4_anylock_blockers __break_lease spin_lock // ctx->flc_lock spin_lock // clp->cl_lock nfs4_lockowner_has_blockers locks_owner_has_blockers spin_lock // flctx->flc_lock nfsd_break_deleg_cb nfsd_break_one_deleg nfs4_put_stid refcount_dec_and_lock spin_lock // clp->cl_lock When a file is opened, an nfs4_delegation is allocated with sc_count initialized to 1, and the file_lease holds a reference to the delegation. The file_lease is then associated with the file through kernel_setlease. The disassociation is performed in nfsd4_delegreturn via the following call chain: nfsd4_delegreturn --> destroy_delegation --> destroy_unhashed_deleg --> nfs4_unlock_deleg_lease --> kernel_setlease --> generic_delete_lease The corresponding sc_count reference will be released after this disassociation. Since nfsd_break_one_deleg executes while holding the flc_lock, the disassociation process becomes blocked when attempting to acquire flc_lock in generic_delete_lease. This means: 1) sc_count in nfsd_break_one_deleg will not be decremented to 0; 2) The nfs4_put_stid called by nfsd_break_one_deleg will not attempt to acquire cl_lock; 3) Consequently, no deadlock condition is created. Given that sc_count in nfsd_break_one_deleg remains non-zero, we can safely perform refcount_dec on sc_count directly. This approach effectively avoids triggering deadlock warnings.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: prevent hang on link training fail [Why] When link training fails, the phy clock will be disabled. However, in enable_streams, it is assumed that link training succeeded and the mux selects the phy clock, causing a hang when a register write is made. [How] When enable_stream is hit, check if link training failed. If it did, fall back to the ref clock to avoid a hang and keep the system in a recoverable state.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Use local fence in error path of xe_migrate_clear The intent of the error path in xe_migrate_clear is to wait on locally generated fence and then return. The code is waiting on m->fence which could be the local fence but this is only stable under the job mutex leading to a possible UAF. Fix code to wait on local fence. (cherry picked from commit 762b7e95362170b3e13a8704f38d5e47eca4ba74)Show less

In the Linux kernel, the following vulnerability has been resolved: drm/xe/userptr: fix notifier vs folio deadlock User is reporting what smells like notifier vs folio deadlock, where migrate_pages_batch() on core kernel side is holding folio lock(s) and then interacting with the mappings of it, however those mappings are tied to some userptr, which means calling into the notifier callback and grabbing the notifier lock. With perfect timing it looks possible that the pages we pulled from the hmm fault can get sniped by migrate_pages_batch() at the same time that we are holding the notifier lock to mark the pages as accessed/dirty, but at this point we also want to grab the folio locks(s) to mark them as dirty, but if they are contended from notifier/migrate_pages_batch side then we deadlock since folio lock won't be dropped until we drop the notifier lock. Fortunately the mark_page_accessed/dirty is not really needed in the first place it seems and should have already been done by hmm fault, so just remove it. (cherry picked from commit bd7c0cb695e87c0e43247be8196b4919edbe0e85)Show less

In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Silence oversized kvmalloc() warning syzkaller triggered an oversized kvmalloc() warning. Silence it by adding __GFP_NOWARN. syzkaller log: WARNING: CPU: 7 PID: 518 at mm/util.c:665 __kvmalloc_node_noprof+0x175/0x180 CPU: 7 UID: 0 PID: 518 Comm: c_repro Not tainted 6.11.0-rc6+ #6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:__kvmalloc_node_noprof+0x175/0x180 RSP: 0018:ffffc90001e67c10 EFLAGS: 00010246 RAX: 0000000000000100 RBX: 0000000000000400 RCX: ffffffff8149d46b RDX: 0000000000000000 RSI: ffff8881030fae80 RDI: 0000000000000002 RBP: 000000712c800000 R08: 0000000000000100 R09: 0000000000000000 R10: ffffc90001e67c10 R11: 0030ae0601000000 R12: 0000000000000000 R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000 FS: 00007fde79159740(0000) GS:ffff88813bdc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000180 CR3: 0000000105eb4005 CR4: 00000000003706b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ib_umem_odp_get+0x1f6/0x390 mlx5_ib_reg_user_mr+0x1e8/0x450 ib_uverbs_reg_mr+0x28b/0x440 ib_uverbs_write+0x7d3/0xa30 vfs_write+0x1ac/0x6c0 ksys_write+0x134/0x170 ? __sanitizer_cov_trace_pc+0x1c/0x50 do_syscall_64+0x50/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7eShow less

In the Linux kernel, the following vulnerability has been resolved: mlxbf-bootctl: use sysfs_emit_at() in secure_boot_fuse_state_show() A warning is seen when running the latest kernel on a BlueField SOC: [251.512704] ------------[ cut here ]------------ [251.512711] invalid sysfs_emit: buf:0000000003aa32ae [251.512720] WARNING: CPU: 1 PID: 705264 at fs/sysfs/file.c:767 sysfs_emit+0xac/0xc8 The warning is triggered because the mlxbf-bootctl driver invokes "sysfs_emit()" with a buffer pointer that is not aligned to the start of the page. The driver should instead use "sysfs_emit_at()" to support non-zero offsets into the destination buffer.Show less

In the Linux kernel, the following vulnerability has been resolved: net: dsa: mv88e6xxx: fix -ENOENT when deleting VLANs and MST is unsupported Russell King reports that on the ZII dev rev B, deleting a bridge VLAN from a user port fails with -ENOENT: https://lore.kernel.org/netdev/Z_lQXNP0s5-IiJzd@shell.armlinux.org.uk/ This comes from mv88e6xxx_port_vlan_leave() -> mv88e6xxx_mst_put(), which tries to find an MST entry in &chip->msts associated with the SID, but fails and returns -ENOENT as such. But we know that this chip does not support MST at all, so that is not surprising. The question is why does the guard in mv88e6xxx_mst_put() not exit early: if (!sid) return 0; And the answer seems to be simple: the sid comes from vlan.sid which supposedly was previously populated by mv88e6xxx_vtu_get(). But some chip->info->ops->vtu_getnext() implementations do not populate vlan.sid, for example see mv88e6185_g1_vtu_getnext(). In that case, later in mv88e6xxx_port_vlan_leave() we are using a garbage sid which is just residual stack memory. Testing for sid == 0 covers all cases of a non-bridge VLAN or a bridge VLAN mapped to the default MSTI. For some chips, SID 0 is valid and installed by mv88e6xxx_stu_setup(). A chip which does not support the STU would implicitly only support mapping all VLANs to the default MSTI, so although SID 0 is not valid, it would be sufficient, if we were to zero-initialize the vlan structure, to fix the bug, due to the coincidence that a test for vlan.sid == 0 already exists and leads to the same (correct) behavior. Another option which would be sufficient would be to add a test for mv88e6xxx_has_stu() inside mv88e6xxx_mst_put(), symmetric to the one which already exists in mv88e6xxx_mst_get(). But that placement means the caller will have to dereference vlan.sid, which means it will access uninitialized memory, which is not nice even if it ignores it later. So we end up making both modifications, in order to not rely just on the sid == 0 coincidence, but also to avoid having uninitialized structure fields which might get temporarily accessed.Show less

In the Linux kernel, the following vulnerability has been resolved: net: dsa: clean up FDB, MDB, VLAN entries on unbind As explained in many places such as commit b117e1e8a86d ("net: dsa: delete dsa_legacy_fdb_add and dsa_legacy_fdb_del"), DSA is written given the assumption that higher layers have balanced additions/deletions. As such, it only makes sense to be extremely vocal when those assumptions are violated and the driver unbinds with entries still present. But Ido Schimmel points out a very simple situation where that is wrong: https://lore.kernel.org/netdev/ZDazSM5UsPPjQuKr@shredder/ (also briefly discussed by me in the aforementioned commit). Basically, while the bridge bypass operations are not something that DSA explicitly documents, and for the majority of DSA drivers this API simply causes them to go to promiscuous mode, that isn't the case for all drivers. Some have the necessary requirements for bridge bypass operations to do something useful - see dsa_switch_supports_uc_filtering(). Although in tools/testing/selftests/net/forwarding/local_termination.sh, we made an effort to popularize better mechanisms to manage address filters on DSA interfaces from user space - namely macvlan for unicast, and setsockopt(IP_ADD_MEMBERSHIP) - through mtools - for multicast, the fact is that 'bridge fdb add ... self static local' also exists as kernel UAPI, and might be useful to someone, even if only for a quick hack. It seems counter-productive to block that path by implementing shim .ndo_fdb_add and .ndo_fdb_del operations which just return -EOPNOTSUPP in order to prevent the ndo_dflt_fdb_add() and ndo_dflt_fdb_del() from running, although we could do that. Accepting that cleanup is necessary seems to be the only option. Especially since we appear to be coming back at this from a different angle as well. Russell King is noticing that the WARN_ON() triggers even for VLANs: https://lore.kernel.org/netdev/Z_li8Bj8bD4-BYKQ@shell.armlinux.org.uk/ What happens in the bug report above is that dsa_port_do_vlan_del() fails, then the VLAN entry lingers on, and then we warn on unbind and leak it. This is not a straight revert of the blamed commit, but we now add an informational print to the kernel log (to still have a way to see that bugs exist), and some extra comments gathered from past years' experience, to justify the logic.Show less

In the Linux kernel, the following vulnerability has been resolved: ovl: don't allow datadir only In theory overlayfs could support upper layer directly referring to a data layer, but there's no current use case for this. Originally, when data-only layers were introduced, this wasn't allowed, only introduced by the "datadir+" feature, but without actually handling this case, resulting in an Oops. Fix by disallowing datadir without lowerdir.Show less

In the Linux kernel, the following vulnerability has been resolved: HID: pidff: Fix null pointer dereference in pidff_find_fields This function triggered a null pointer dereference if used to search for a report that isn't implemented on the device. This happened both for optional and required reports alike. The same logic was applied to pidff_find_special_field and although pidff_init_fields should return an error earlier if one of the required reports is missing, future modifications could change this logic and resurface this possible null pointer dereference again. LKML bug report: https://lore.kernel.org/all/CAL-gK7f5=R0nrrQdPtaZZr1fd-cdAMbDMuZ_NLA8vM0SX+nGSw@mail.gmail.comShow less

In the Linux kernel, the following vulnerability has been resolved: scsi: mpi3mr: Synchronous access b/w reset and tm thread for reply queue When the task management thread processes reply queues while the reset thread resets them, the task management thread accesses an invalid queue ID (0xFFFF), set by the reset thread, which points to unallocated memory, causing a crash. Add flag 'io_admin_reset_sync' to synchronize access between the reset, I/O, and admin threads. Before a reset, the reset handler sets this flag to block I/O and admin processing threads. If any thread bypasses the initial check, the reset thread waits up to 10 seconds for processing to finish. If the wait exceeds 10 seconds, the controller is marked as unrecoverable.Show less

In the Linux kernel, the following vulnerability has been resolved: page_pool: avoid infinite loop to schedule delayed worker We noticed the kworker in page_pool_release_retry() was waken up repeatedly and infinitely in production because of the buggy driver causing the inflight less than 0 and warning us in page_pool_inflight()[1]. Since the inflight value goes negative, it means we should not expect the whole page_pool to get back to work normally. This patch mitigates the adverse effect by not rescheduling the kworker when detecting the inflight negative in page_pool_release_retry(). [1] [Mon Feb 10 20:36:11 2025] ------------[ cut here ]------------ [Mon Feb 10 20:36:11 2025] Negative(-51446) inflight packet-pages ... [Mon Feb 10 20:36:11 2025] Call Trace: [Mon Feb 10 20:36:11 2025] page_pool_release_retry+0x23/0x70 [Mon Feb 10 20:36:11 2025] process_one_work+0x1b1/0x370 [Mon Feb 10 20:36:11 2025] worker_thread+0x37/0x3a0 [Mon Feb 10 20:36:11 2025] kthread+0x11a/0x140 [Mon Feb 10 20:36:11 2025] ? process_one_work+0x370/0x370 [Mon Feb 10 20:36:11 2025] ? __kthread_cancel_work+0x40/0x40 [Mon Feb 10 20:36:11 2025] ret_from_fork+0x35/0x40 [Mon Feb 10 20:36:11 2025] ---[ end trace ebffe800f33e7e34 ]--- Note: before this patch, the above calltrace would flood the dmesg due to repeated reschedule of release_dw kworker.Show less

In the Linux kernel, the following vulnerability has been resolved: fs/jfs: Prevent integer overflow in AG size calculation The JFS filesystem calculates allocation group (AG) size using 1 << l2agsize in dbExtendFS(). When l2agsize exceeds 31 (possible with >2TB aggregates on 32-bit systems), this 32-bit shift operation causes undefined behavior and improper AG sizing. On 32-bit architectures: - Left-shifting 1 by 32+ bits results in 0 due to integer overflow - This creates invalid AG sizes (0 or garbage values) in sbi->bmap->db_agsize - Subsequent block allocations would reference invalid AG structures - Could lead to: - Filesystem corruption during extend operations - Kernel crashes due to invalid memory accesses - Security vulnerabilities via malformed on-disk structures Fix by casting to s64 before shifting: bmp->db_agsize = (s64)1 << l2agsize; This ensures 64-bit arithmetic even on 32-bit architectures. The cast matches the data type of db_agsize (s64) and follows similar patterns in JFS block calculation code. Found by Linux Verification Center (linuxtesting.org) with SVACE.Show less