Description
In the Linux kernel, the following vulnerability has been resolved: ext4: Fix function prototype mismatch for ext4_feat_ktype With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG), indirect call targets are validated against the expected function pointer prototype to make sure the call target is valid to help mitigate ROP attacks. If they are not identical, there is a failure at run time, which manifests as either a kernel panic or thread getting killed. ext4_feat_ktype was setting the "release" handler to "kfree", which doesn't have a matching function prototype. Add a simple wrapper with the correct prototype. This was found as a result of Clang's new -Wcast-function-type-strict flag, which is more sensitive than the simpler -Wcast-function-type, which only checks for type width mismatches. Note that this code is only reached when ext4 is a loadable module and it is being unloaded: CFI failure at kobject_put+0xbb/0x1b0 (target: kfree+0x0/0x180; expected type: 0x7c4aa698) ... RIP: 0010:kobject_put+0xbb/0x1b0 ... Call Trace: <TASK> ext4_exit_sysfs+0x14/0x60 [ext4] cleanup_module+0x67/0xedb [ext4]
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
b99fee58a20ab8e0557cce87b6f187e325993142 to < 2b69cdd9f9a7f596e3dd31f05f9852940d177924affectedb99fee58a20ab8e0557cce87b6f187e325993142 to < 99e3fd21f8fc975c95e8cf76fbf6a3d2656f8f71affectedb99fee58a20ab8e0557cce87b6f187e325993142 to < 1ba10d3640e9783dad811fe4e24d55465c37c64daffectedb99fee58a20ab8e0557cce87b6f187e325993142 to < c98077f7598a562f51051eec043be0cb3e1b1b5eaffectedb99fee58a20ab8e0557cce87b6f187e325993142 to < 0a1394e07c5d6bf1bfc25db8589ff1b1bfb6f46aaffectedb99fee58a20ab8e0557cce87b6f187e325993142 to < 94d8de83286fb1827340eba35b61c308f6b46eadaffectedb99fee58a20ab8e0557cce87b6f187e325993142 to < 118901ad1f25d2334255b3d50512fa20591531cdaffected
Linux Linux
Default version status: affected
4.16affected0 to < 4.16unaffected4.19.274 to ≤ 4.19.*unaffected5.4.233 to ≤ 5.4.*unaffected5.10.170 to ≤ 5.10.*unaffected5.15.96 to ≤ 5.15.*unaffected6.1.14 to ≤ 6.1.*unaffected6.2.1 to ≤ 6.2.*unaffected6.3 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/2b69cdd9f9a7f596e3dd31f05f9852940d177924 ↗
- https://git.kernel.org/stable/c/99e3fd21f8fc975c95e8cf76fbf6a3d2656f8f71 ↗
- https://git.kernel.org/stable/c/1ba10d3640e9783dad811fe4e24d55465c37c64d ↗
- https://git.kernel.org/stable/c/c98077f7598a562f51051eec043be0cb3e1b1b5e ↗
- https://git.kernel.org/stable/c/0a1394e07c5d6bf1bfc25db8589ff1b1bfb6f46a ↗
- https://git.kernel.org/stable/c/94d8de83286fb1827340eba35b61c308f6b46ead ↗
- https://git.kernel.org/stable/c/118901ad1f25d2334255b3d50512fa20591531cd ↗