| 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-2024-26999: serial/pmac_zilog: Remove flawed mitigation for rx irq flood |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| serial/pmac_zilog: Remove flawed mitigation for rx irq flood |
| |
| The mitigation was intended to stop the irq completely. That may be |
| better than a hard lock-up but it turns out that you get a crash anyway |
| if you're using pmac_zilog as a serial console: |
| |
| ttyPZ0: pmz: rx irq flood ! |
| BUG: spinlock recursion on CPU#0, swapper/0 |
| |
| That's because the pr_err() call in pmz_receive_chars() results in |
| pmz_console_write() attempting to lock a spinlock already locked in |
| pmz_interrupt(). With CONFIG_DEBUG_SPINLOCK=y, this produces a fatal |
| BUG splat. The spinlock in question is the one in struct uart_port. |
| |
| Even when it's not fatal, the serial port rx function ceases to work. |
| Also, the iteration limit doesn't play nicely with QEMU, as can be |
| seen in the bug report linked below. |
| |
| A web search for other reports of the error message "pmz: rx irq flood" |
| didn't produce anything. So I don't think this code is needed any more. |
| Remove it. |
| |
| The Linux kernel CVE team has assigned CVE-2024-26999 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 4.19.313 with commit 69a02273e288011b521ee7c1f3ab2c23fda633ce |
| Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 5.4.275 with commit d679c816929d62af51c8e6d7fc0e165c9412d2f3 |
| Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 5.10.216 with commit ab86cf6f8d24e63e9aca23da5108af1aa5483928 |
| Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 5.15.157 with commit 7a3bbe41efa55323b6ea3c35fa15941d4dbecdef |
| Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.1.88 with commit bbaafbb4651fede8d3c3881601ecaa4f834f9d3f |
| Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.6.29 with commit 52aaf1ff14622a04148dbb9ccce6d9de5d534ea7 |
| Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.8.8 with commit ca09dfc3cfdf89e6af3ac24e1c6c0be5c575a729 |
| Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.9 with commit 1be3226445362bfbf461c92a5bcdb1723f2e4907 |
| |
| 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-2024-26999 |
| 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/tty/serial/pmac_zilog.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/69a02273e288011b521ee7c1f3ab2c23fda633ce |
| https://git.kernel.org/stable/c/d679c816929d62af51c8e6d7fc0e165c9412d2f3 |
| https://git.kernel.org/stable/c/ab86cf6f8d24e63e9aca23da5108af1aa5483928 |
| https://git.kernel.org/stable/c/7a3bbe41efa55323b6ea3c35fa15941d4dbecdef |
| https://git.kernel.org/stable/c/bbaafbb4651fede8d3c3881601ecaa4f834f9d3f |
| https://git.kernel.org/stable/c/52aaf1ff14622a04148dbb9ccce6d9de5d534ea7 |
| https://git.kernel.org/stable/c/ca09dfc3cfdf89e6af3ac24e1c6c0be5c575a729 |
| https://git.kernel.org/stable/c/1be3226445362bfbf461c92a5bcdb1723f2e4907 |
