CVE-2026-43249
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2026
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
9p/xen: protect xen_9pfs_front_free against concurrent calls
In the Linux kernel, the following vulnerability has been resolved: 9p/xen: protect xen_9pfs_front_free against concurrent calls The xenwatch thread can race with other back-end change notifications and call xen_9pfs_front_free() twice, hitting the observed general protection fault due to a double-free. Guard the teardown path so only one caller can release the front-end state at a time, preventing the crash. This is a fix for the following double-free: [ 27.052347] Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] SMP DEBUG_PAGEALLOC NOPTI [ 27.052357] CPU: 0 UID: 0 PID: 32 Comm: xenwatch Not tainted 6.18.0-02087-g51ab33fc0a8b-dirty #60 PREEMPT(none) [ 27.052363] RIP: e030:xen_9pfs_front_free+0x1d/0x150 [ 27.052368] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 41 55 41 54 55 48 89 fd 48 c7 c7 48 d0 92 85 53 e8 cb cb 05 00 48 8b 45 08 48 8b 55 00 <48> 3b 28 0f 85 f9 28 35 fe 48 3b 6a 08 0f 85 ef 28 35 fe 48 89 42 [ 27.052377] RSP: e02b:ffffc9004016fdd0 EFLAGS: 00010246 [ 27.052381] RAX: 6b6b6b6b6b6b6b6b RBX: ffff88800d66e400 RCX: 0000000000000000 [ 27.052385] RDX: 6b6b6b6b6b6b6b6b RSI: 0000000000000000 RDI: 0000000000000000 [ 27.052389] RBP: ffff88800a887040 R08: 0000000000000000 R09: 0000000000000000 [ 27.052393] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888009e46b68 [ 27.052397] R13: 0000000000000200 R14: 0000000000000000 R15: ffff88800a887040 [ 27.052404] FS: 0000000000000000(0000) GS:ffff88808ca57000(0000) knlGS:0000000000000000 [ 27.052408] CS: e030 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 27.052412] CR2: 00007f9714004360 CR3: 0000000004834000 CR4: 0000000000050660 [ 27.052418] Call Trace: [ 27.052420] <TASK> [ 27.052422] xen_9pfs_front_changed+0x5d5/0x720 [ 27.052426] ? xenbus_otherend_changed+0x72/0x140 [ 27.052430] ? __pfx_xenwatch_thread+0x10/0x10 [ 27.052434] xenwatch_thread+0x94/0x1c0 [ 27.052438] ? __pfx_autoremove_wake_function+0x10/0x10 [ 27.052442] kthread+0xf8/0x240 [ 27.052445] ? __pfx_kthread+0x10/0x10 [ 27.052449] ? __pfx_kthread+0x10/0x10 [ 27.052452] ret_from_fork+0x16b/0x1a0 [ 27.052456] ? __pfx_kthread+0x10/0x10 [ 27.052459] ret_from_fork_asm+0x1a/0x30 [ 27.052463] </TASK> [ 27.052465] Modules linked in: [ 27.052471] ---[ end trace 0000000000000000 ]---
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
unaffected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| c15fe55d14b3b4ded5af2a3260877460a6ffb8ad | affected | git | 480aa6ffd4ac7036eea042047d0cca71bc2074bb | Unavailable | None listed |
| c15fe55d14b3b4ded5af2a3260877460a6ffb8ad | affected | git | a5d00dff97118a32fcf5fec7a4c3f864c4620c4e | Unavailable | None listed |
| c15fe55d14b3b4ded5af2a3260877460a6ffb8ad | affected | git | 59e7707492576bdbfa8c1dbe7d90791df31e4773 | Unavailable | None listed |
| c15fe55d14b3b4ded5af2a3260877460a6ffb8ad | affected | git | bf841d43f7a33d75675ba7f4e214ac1c67913065 | Unavailable | None listed |
| c15fe55d14b3b4ded5af2a3260877460a6ffb8ad | affected | git | ce8ded2e61f47747e31eeefb44dc24a2160a7e32 | Unavailable | None listed |
| be03c4fe72384366fd4077a70966bd3b8fc49013 | affected | git | Unavailable | Unavailable | None listed |
| 1ab4de11232e83b875b071aa44d1155634ca8a1e | affected | git | Unavailable | Unavailable | None listed |
| 7cc9dbae8a5f73bd555130384ea256018d28f283 | affected | git | Unavailable | Unavailable | None listed |
| 3e0359f151ac151abe3fa71040e450ed69cb824b | affected | git | Unavailable | Unavailable | None listed |
| 8d3fc907d060c4fb33203e616a395a22083b6566 | affected | git | Unavailable | Unavailable | None listed |
| 4f0e9244770f5b75a16d8c0929063cd336926764 | affected | git | Unavailable | Unavailable | None listed |
| 5f6a8974e9ef317fe63f88bab1f33070195dd147 | affected | git | Unavailable | Unavailable | None listed |
| 4.14.308 | affected | semver | 4.15 | Unavailable | None listed |
| 4.19.276 | affected | semver | 4.20 | Unavailable | None listed |
| 5.4.235 | affected | semver | 5.5 | Unavailable | None listed |
| 5.10.173 | affected | semver | 5.11 | Unavailable | None listed |
| 5.15.100 | affected | semver | 5.16 | Unavailable | None listed |
| 6.1.18 | affected | semver | 6.2 | Unavailable | None listed |
| 6.2.5 | affected | semver | 6.3 | Unavailable | None listed |
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
affected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 6.3 | affected | Unavailable | Unavailable | Unavailable | None listed |
| 0 | unaffected | semver | 6.3 | Unavailable | None listed |
| 6.6.160 | unaffected | semver | Unavailable | 6.6.* | None listed |
| 6.12.75 | unaffected | semver | Unavailable | 6.12.* | None listed |
| 6.18.16 | unaffected | semver | Unavailable | 6.18.* | None listed |
| 6.19.6 | unaffected | semver | Unavailable | 6.19.* | None listed |
| 7.0 | unaffected | original_commit_for_fix | Unavailable | * | None listed |