Vulnerabilidades

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> drm/amdkfd: Unreserve bo if queue update failed<br /> <br /> Error handling path should unreserve bo then return failed.<br /> <br /> (cherry picked from commit c24afed7de9ecce341825d8ab55a43a254348b33)

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> e1000/e1000e: Fix leak in DMA error cleanup<br /> <br /> If an error is encountered while mapping TX buffers, the driver should<br /> unmap any buffers already mapped for that skb.<br /> <br /> Because count is incremented after a successful mapping, it will always<br /> match the correct number of unmappings needed when dma_error is reached.<br /> Decrementing count before the while loop in dma_error causes an<br /> off-by-one error. If any mapping was successful before an unsuccessful<br /> mapping, exactly one DMA mapping would leak.<br /> <br /> In these commits, a faulty while condition caused an infinite loop in<br /> dma_error:<br /> Commit 03b1320dfcee ("e1000e: remove use of skb_dma_map from e1000e<br /> driver")<br /> Commit 602c0554d7b0 ("e1000: remove use of skb_dma_map from e1000 driver")<br /> <br /> Commit c1fa347f20f1 ("e1000/e1000e/igb/igbvf/ixgb/ixgbe: Fix tests of<br /> unsigned in *_tx_map()") fixed the infinite loop, but introduced the<br /> off-by-one error.<br /> <br /> This issue may still exist in the igbvf driver, but I did not address it<br /> in this patch.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> USB: usbtmc: Use usb_bulk_msg_killable() with user-specified timeouts<br /> <br /> The usbtmc driver accepts timeout values specified by the user in an<br /> ioctl command, and uses these timeouts for some usb_bulk_msg() calls.<br /> Since the user can specify arbitrarily long timeouts and<br /> usb_bulk_msg() uses unkillable waits, call usb_bulk_msg_killable()<br /> instead to avoid the possibility of the user hanging a kernel thread<br /> indefinitely.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> usb: yurex: fix race in probe<br /> <br /> The bbu member of the descriptor must be set to the value<br /> standing for uninitialized values before the URB whose<br /> completion handler sets bbu is submitted. Otherwise there is<br /> a window during which probing can overwrite already retrieved<br /> data.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> xhci: Fix NULL pointer dereference when reading portli debugfs files<br /> <br /> Michal reported and debgged a NULL pointer dereference bug in the<br /> recently added portli debugfs files<br /> <br /> Oops is caused when there are more port registers counted in<br /> xhci-&gt;max_ports than ports reported by Supported Protocol capabilities.<br /> This is possible if max_ports is more than maximum port number, or<br /> if there are gaps between ports of different speeds the &amp;#39;Supported<br /> Protocol&amp;#39; capabilities.<br /> <br /> In such cases port-&gt;rhub will be NULL so we can&amp;#39;t reach xhci behind it.<br /> Add an explicit NULL check for this case, and print portli in hex<br /> without dereferencing port-&gt;rhub.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> usb: xhci: Fix memory leak in xhci_disable_slot()<br /> <br /> xhci_alloc_command() allocates a command structure and, when the<br /> second argument is true, also allocates a completion structure.<br /> Currently, the error handling path in xhci_disable_slot() only frees<br /> the command structure using kfree(), causing the completion structure<br /> to leak.<br /> <br /> Use xhci_free_command() instead of kfree(). xhci_free_command() correctly<br /> frees both the command structure and the associated completion structure.<br /> Since the command structure is allocated with zero-initialization,<br /> command-&gt;in_ctx is NULL and will not be erroneously freed by<br /> xhci_free_command().<br /> <br /> This bug was found using an experimental static analysis tool we are<br /> developing. The tool is based on the LLVM framework and is specifically<br /> designed to detect memory management issues. It is currently under<br /> active development and not yet publicly available, but we plan to<br /> open-source it after our research is published.<br /> <br /> The bug was originally detected on v6.13-rc1 using our static analysis<br /> tool, and we have verified that the issue persists in the latest mainline<br /> kernel.<br /> <br /> We performed build testing on x86_64 with allyesconfig using GCC=11.4.0.<br /> Since triggering these error paths in xhci_disable_slot() requires specific<br /> hardware conditions or abnormal state, we were unable to construct a test<br /> case to reliably trigger these specific error paths at runtime.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> rust_binder: avoid reading the written value in offsets array<br /> <br /> When sending a transaction, its offsets array is first copied into the<br /> target proc&amp;#39;s vma, and then the values are read back from there. This is<br /> normally fine because the vma is a read-only mapping, so the target<br /> process cannot change the value under us.<br /> <br /> However, if the target process somehow gains the ability to write to its<br /> own vma, it could change the offset before it&amp;#39;s read back, causing the<br /> kernel to misinterpret what the sender meant. If the sender happens to<br /> send a payload with a specific shape, this could in the worst case lead<br /> to the receiver being able to privilege escalate into the sender.<br /> <br /> The intent is that gaining the ability to change the read-only vma of<br /> your own process should not be exploitable, so remove this TOCTOU read<br /> even though it&amp;#39;s unexploitable without another Binder bug.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> rust_binder: check ownership before using vma<br /> <br /> When installing missing pages (or zapping them), Rust Binder will look<br /> up the vma in the mm by address, and then call vm_insert_page (or<br /> zap_page_range_single). However, if the vma is closed and replaced with<br /> a different vma at the same address, this can lead to Rust Binder<br /> installing pages into the wrong vma.<br /> <br /> By installing the page into a writable vma, it becomes possible to write<br /> to your own binder pages, which are normally read-only. Although you&amp;#39;re<br /> not supposed to be able to write to those pages, the intent behind the<br /> design of Rust Binder is that even if you get that ability, it should not<br /> lead to anything bad. Unfortunately, due to another bug, that is not the<br /> case.<br /> <br /> To fix this, store a pointer in vm_private_data and check that the vma<br /> returned by vma_lookup() has the right vm_ops and vm_private_data before<br /> trying to use the vma. This should ensure that Rust Binder will refuse<br /> to interact with any other VMA. The plan is to introduce more vma<br /> abstractions to avoid this unsafe access to vm_ops and vm_private_data,<br /> but for now let&amp;#39;s start with the simplest possible fix.<br /> <br /> C Binder performs the same check in a slightly different way: it<br /> provides a vm_ops-&gt;close that sets a boolean to true, then checks that<br /> boolean after calling vma_lookup(), but this is more fragile<br /> than the solution in this patch. (We probably still want to do both, but<br /> the vm_ops-&gt;close callback will be added later as part of the follow-up<br /> vma API changes.)<br /> <br /> It&amp;#39;s still possible to remap the vma so that pages appear in the right<br /> vma, but at the wrong offset, but this is a separate issue and will be<br /> fixed when Rust Binder gets a vm_ops-&gt;close callback.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> rust_binder: fix oneway spam detection<br /> <br /> The spam detection logic in TreeRange was executed before the current<br /> request was inserted into the tree. So the new request was not being<br /> factored in the spam calculation. Fix this by moving the logic after<br /> the new range has been inserted.<br /> <br /> Also, the detection logic for ArrayRange was missing altogether which<br /> meant large spamming transactions could get away without being detected.<br /> Fix this by implementing an equivalent low_oneway_space() in ArrayRange.<br /> <br /> Note that I looked into centralizing this logic in RangeAllocator but<br /> iterating through &amp;#39;state&amp;#39; and &amp;#39;size&amp;#39; got a bit too complicated (for me)<br /> and I abandoned this effort.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ALSA: usb-audio: Check endpoint numbers at parsing Scarlett2 mixer interfaces<br /> <br /> The Scarlett2 mixer quirk in USB-audio driver may hit a NULL<br /> dereference when a malformed USB descriptor is passed, since it<br /> assumes the presence of an endpoint in the parsed interface in<br /> scarlett2_find_fc_interface(), as reported by fuzzer.<br /> <br /> For avoiding the NULL dereference, just add the sanity check of<br /> bNumEndpoints and skip the invalid interface.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ceph: fix i_nlink underrun during async unlink<br /> <br /> During async unlink, we drop the `i_nlink` counter before we receive<br /> the completion (that will eventually update the `i_nlink`) because "we<br /> assume that the unlink will succeed". That is not a bad idea, but it<br /> races against deletions by other clients (or against the completion of<br /> our own unlink) and can lead to an underrun which emits a WARNING like<br /> this one:<br /> <br /> WARNING: CPU: 85 PID: 25093 at fs/inode.c:407 drop_nlink+0x50/0x68<br /> Modules linked in:<br /> CPU: 85 UID: 3221252029 PID: 25093 Comm: php-cgi8.1 Not tainted 6.14.11-cm4all1-ampere #655<br /> Hardware name: Supermicro ARS-110M-NR/R12SPD-A, BIOS 1.1b 10/17/2023<br /> pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)<br /> pc : drop_nlink+0x50/0x68<br /> lr : ceph_unlink+0x6c4/0x720<br /> sp : ffff80012173bc90<br /> x29: ffff80012173bc90 x28: ffff086d0a45aaf8 x27: ffff0871d0eb5680<br /> x26: ffff087f2a64a718 x25: 0000020000000180 x24: 0000000061c88647<br /> x23: 0000000000000002 x22: ffff07ff9236d800 x21: 0000000000001203<br /> x20: ffff07ff9237b000 x19: ffff088b8296afc0 x18: 00000000f3c93365<br /> x17: 0000000000070000 x16: ffff08faffcbdfe8 x15: ffff08faffcbdfec<br /> x14: 0000000000000000 x13: 45445f65645f3037 x12: 34385f6369706f74<br /> x11: 0000a2653104bb20 x10: ffffd85f26d73290 x9 : ffffd85f25664f94<br /> x8 : 00000000000000c0 x7 : 0000000000000000 x6 : 0000000000000002<br /> x5 : 0000000000000081 x4 : 0000000000000481 x3 : 0000000000000000<br /> x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff08727d3f91e8<br /> Call trace:<br /> drop_nlink+0x50/0x68 (P)<br /> vfs_unlink+0xb0/0x2e8<br /> do_unlinkat+0x204/0x288<br /> __arm64_sys_unlinkat+0x3c/0x80<br /> invoke_syscall.constprop.0+0x54/0xe8<br /> do_el0_svc+0xa4/0xc8<br /> el0_svc+0x18/0x58<br /> el0t_64_sync_handler+0x104/0x130<br /> el0t_64_sync+0x154/0x158<br /> <br /> In ceph_unlink(), a call to ceph_mdsc_submit_request() submits the<br /> CEPH_MDS_OP_UNLINK to the MDS, but does not wait for completion.<br /> <br /> Meanwhile, between this call and the following drop_nlink() call, a<br /> worker thread may process a CEPH_CAP_OP_IMPORT, CEPH_CAP_OP_GRANT or<br /> just a CEPH_MSG_CLIENT_REPLY (the latter of which could be our own<br /> completion). These will lead to a set_nlink() call, updating the<br /> `i_nlink` counter to the value received from the MDS. If that new<br /> `i_nlink` value happens to be zero, it is illegal to decrement it<br /> further. But that is exactly what ceph_unlink() will do then.<br /> <br /> The WARNING can be reproduced this way:<br /> <br /> 1. Force async unlink; only the async code path is affected. Having<br /> no real clue about Ceph internals, I was unable to find out why the<br /> MDS wouldn&amp;#39;t give me the "Fxr" capabilities, so I patched<br /> get_caps_for_async_unlink() to always succeed.<br /> <br /> (Note that the WARNING dump above was found on an unpatched kernel,<br /> without this kludge - this is not a theoretical bug.)<br /> <br /> 2. Add a sleep call after ceph_mdsc_submit_request() so the unlink<br /> completion gets handled by a worker thread before drop_nlink() is<br /> called. This guarantees that the `i_nlink` is already zero before<br /> drop_nlink() runs.<br /> <br /> The solution is to skip the counter decrement when it is already zero,<br /> but doing so without a lock is still racy (TOCTOU). Since<br /> ceph_fill_inode() and handle_cap_grant() both hold the<br /> `ceph_inode_info.i_ceph_lock` spinlock while set_nlink() runs, this<br /> seems like the proper lock to protect the `i_nlink` updates.<br /> <br /> I found prior art in NFS and SMB (using `inode.i_lock`) and AFS (using<br /> `afs_vnode.cb_lock`). All three have the zero check as well.

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> usb: gadget: f_ncm: Fix net_device lifecycle with device_move<br /> <br /> The network device outlived its parent gadget device during<br /> disconnection, resulting in dangling sysfs links and null pointer<br /> dereference problems.<br /> <br /> A prior attempt to solve this by removing SET_NETDEV_DEV entirely [1]<br /> was reverted due to power management ordering concerns and a NO-CARRIER<br /> regression.<br /> <br /> A subsequent attempt to defer net_device allocation to bind [2] broke<br /> 1:1 mapping between function instance and network device, making it<br /> impossible for configfs to report the resolved interface name. This<br /> results in a regression where the DHCP server fails on pmOS.<br /> <br /> Use device_move to reparent the net_device between the gadget device and<br /> /sys/devices/virtual/ across bind/unbind cycles. This preserves the<br /> network interface across USB reconnection, allowing the DHCP server to<br /> retain their binding.<br /> <br /> Introduce gether_attach_gadget()/gether_detach_gadget() helpers and use<br /> __free(detach_gadget) macro to undo attachment on bind failure. The<br /> bind_count ensures device_move executes only on the first bind.<br /> <br /> [1] https://lore.kernel.org/lkml/f2a4f9847617a0929d62025748384092e5f35cce.camel@crapouillou.net/<br /> [2] https://lore.kernel.org/linux-usb/795ea759-7eaf-4f78-81f4-01ffbf2d7961@ixit.cz/