Messages in this thread | | | From | gilad kleinman <> | Date | Wed, 18 Mar 2020 21:46:35 +0200 | Subject | Re: [PATCH] x86/module: Fixed bug allowing invalid relocation addresses. |
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When you load a bad module and the kernel crashes -- the panic message will usually be related to the module and easily traced back. If you load a module with a bad relocation table (because of a bit-flip \ bad toolchain), it will override other kernel code, resulting in an impossible to trace back kernel panic.
On Mon, Mar 16, 2020 at 2:58 PM Peter Zijlstra <peterz@infradead.org> wrote: > > On Sat, Mar 14, 2020 at 11:36:26PM +0200, Gilad Wharton Kleinman wrote: > > If a kernel module with a bad relocation offset is loaded to a x86 kernel, > > the kernel will apply the relocation to a address not inside the module > > (resulting in memory in the kernel being overridden). > > Why !? > > If you load a bad module it's game over anyway. At best this protects us > from broken toolchains.
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