Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: habanalabs: fix UAF in export_dmabuf() As soon as we'd inserted a file reference into descriptor table, another thread could close it. That's fine for the case when all we are doing is returning that descriptor to userland (it's a race, but it's a userland race and there's nothing the kernel can do about it). However, if we follow fd_install() with any kind of access to objects that would be destroyed on close (be it the struct file itself or anything destroyed by its ->release()), we have a UAF. dma_buf_fd() is a combination of reserving a descriptor and fd_install(). habanalabs export_dmabuf() calls it and then proceeds to access the objects destroyed on close. In particular, it grabs an extra reference to another struct file that will be dropped as part of ->release() for ours; that "will be" is actually "might have already been". Fix that by reserving descriptor before anything else and do fd_install() only when everything had been set up. As a side benefit, we no longer have the failure exit with file already created, but reference to underlying file (as well as ->dmabuf_export_cnt, etc.) not grabbed yet; unlike dma_buf_fd(), fd_install() can't fail.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected db1a8dd916aac986871f6b873a3aefad906f383a before d26058c2349d77d1ef179a2cc9752ca12004b6ff; affected db1a8dd916aac986871f6b873a3aefad906f383a before c07886761fd6251db6938d4e747002e3d150d231; affected db1a8dd916aac986871f6b873a3aefad906f383a before 40deceb38f9db759772d1c289c28fd2a543f57fc; affected db1a8dd916aac986871f6b873a3aefad906f383a before 55c232d7e0241f1d5120b595e7a9de24c75ed3d8; affected db1a8dd916aac986871f6b873a3aefad906f383a before 33927f3d0ecdcff06326d6e4edb6166aed42811c |
| Linux / Linux | affected 5.16; unaffected 0 before 5.16; unaffected 6.6.160 through 6.6.*; unaffected 6.12.43 through 6.12.*; unaffected 6.15.11 through 6.15.*; unaffected 6.16.2 through 6.16.*; unaffected 6.17 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/d26058c2349d77d1ef179a2cc9752ca12004b6ff
- https://git.kernel.org/stable/c/c07886761fd6251db6938d4e747002e3d150d231
- https://git.kernel.org/stable/c/40deceb38f9db759772d1c289c28fd2a543f57fc
- https://git.kernel.org/stable/c/55c232d7e0241f1d5120b595e7a9de24c75ed3d8
- https://git.kernel.org/stable/c/33927f3d0ecdcff06326d6e4edb6166aed42811c