| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-35825: usb: gadget: ncm: Fix handling of zero block length packets |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| usb: gadget: ncm: Fix handling of zero block length packets |
| |
| While connecting to a Linux host with CDC_NCM_NTB_DEF_SIZE_TX |
| set to 65536, it has been observed that we receive short packets, |
| which come at interval of 5-10 seconds sometimes and have block |
| length zero but still contain 1-2 valid datagrams present. |
| |
| According to the NCM spec: |
| |
| "If wBlockLength = 0x0000, the block is terminated by a |
| short packet. In this case, the USB transfer must still |
| be shorter than dwNtbInMaxSize or dwNtbOutMaxSize. If |
| exactly dwNtbInMaxSize or dwNtbOutMaxSize bytes are sent, |
| and the size is a multiple of wMaxPacketSize for the |
| given pipe, then no ZLP shall be sent. |
| |
| wBlockLength= 0x0000 must be used with extreme care, because |
| of the possibility that the host and device may get out of |
| sync, and because of test issues. |
| |
| wBlockLength = 0x0000 allows the sender to reduce latency by |
| starting to send a very large NTB, and then shortening it when |
| the sender discovers that there’s not sufficient data to justify |
| sending a large NTB" |
| |
| However, there is a potential issue with the current implementation, |
| as it checks for the occurrence of multiple NTBs in a single |
| giveback by verifying if the leftover bytes to be processed is zero |
| or not. If the block length reads zero, we would process the same |
| NTB infintely because the leftover bytes is never zero and it leads |
| to a crash. Fix this by bailing out if block length reads zero. |
| |
| The Linux kernel CVE team has assigned CVE-2024-35825 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.19.297 with commit ff3ba016263ee93a1c6209bf5ab1599de7ab1512 and fixed in 4.19.312 with commit e2dbfea520e60d58e0c498ba41bde10452257779 |
| Issue introduced in 5.4.259 with commit e7ca00f35d8a17af1ae19d529193ebc21bfda164 and fixed in 5.4.274 with commit a766761d206e7c36d7526e0ae749949d17ca582c |
| Issue introduced in 5.10.199 with commit 17c653d4913bbc50d284aa96cf12bfc63e41ee5c and fixed in 5.10.215 with commit ef846cdbd100f7f9dc045e8bcd7fe4b3a3713c03 |
| Issue introduced in 5.15.136 with commit 7014807fb7efa169a47a7a0a0a41d2c513925de0 and fixed in 5.15.154 with commit 92b051b87658df7649ffcdef522593f21a2b296b |
| Issue introduced in 6.1.59 with commit 49fbc18378ae72a47feabee97fdb86f3cea09765 and fixed in 6.1.84 with commit 7664ee8bd80309b90d53488b619764f0a057f2b7 |
| Issue introduced in 6.6 with commit 427694cfaafa565a3db5c5ea71df6bc095dca92f and fixed in 6.6.24 with commit a0f77b5d6067285b8eca0ee3bd1e448a6258026f |
| Issue introduced in 6.6 with commit 427694cfaafa565a3db5c5ea71df6bc095dca92f and fixed in 6.7.12 with commit 6b2c73111a252263807b7598682663dc33aa4b4c |
| Issue introduced in 6.6 with commit 427694cfaafa565a3db5c5ea71df6bc095dca92f and fixed in 6.8 with commit f90ce1e04cbcc76639d6cba0fdbd820cd80b3c70 |
| Issue introduced in 4.14.328 with commit 5bdf93a2f5459f944b416b188178ca4a92fd206f |
| Issue introduced in 6.5.8 with commit 4bf1a9d20c65b9e80ca4b171267103f8d4f2c61f |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-35825 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/usb/gadget/function/f_ncm.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/e2dbfea520e60d58e0c498ba41bde10452257779 |
| https://git.kernel.org/stable/c/a766761d206e7c36d7526e0ae749949d17ca582c |
| https://git.kernel.org/stable/c/ef846cdbd100f7f9dc045e8bcd7fe4b3a3713c03 |
| https://git.kernel.org/stable/c/92b051b87658df7649ffcdef522593f21a2b296b |
| https://git.kernel.org/stable/c/7664ee8bd80309b90d53488b619764f0a057f2b7 |
| https://git.kernel.org/stable/c/a0f77b5d6067285b8eca0ee3bd1e448a6258026f |
| https://git.kernel.org/stable/c/6b2c73111a252263807b7598682663dc33aa4b4c |
| https://git.kernel.org/stable/c/f90ce1e04cbcc76639d6cba0fdbd820cd80b3c70 |
