| From: "Mike Rapoport (Microsoft)" <rppt@kernel.org> |
| Subject: x86/alternatives: fix writable address in cfi_rewrite_endbr() |
| Date: Tue, 5 Nov 2024 10:49:57 +0200 |
| |
| Commit ("x86/module: prepare module loading for ROX allocations of text") |
| missed the offset that should be added to the writable address passed to |
| poison_endbr() from cfi_rewrite_endbr() and this causes boot failures on |
| kernels running with cfi=fineibt on machines that support IBT. |
| |
| Add required offset to wr_addr argument to fix the issue. |
| |
| Link: https://lkml.kernel.org/r/ZysRwR29Ji8CcbXc@kernel.org |
| Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> |
| Reported-by: Nathan Chancellor <nathan@kernel.org> |
| Tested-by: Nathan Chancellor <nathan@kernel.org> |
| Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
| --- |
| |
| arch/x86/kernel/alternative.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/arch/x86/kernel/alternative.c~x86-module-prepare-module-loading-for-rox-allocations-of-text-fix |
| +++ a/arch/x86/kernel/alternative.c |
| @@ -1241,7 +1241,7 @@ static void cfi_rewrite_endbr(s32 *start |
| void *addr = (void *)s + *s; |
| void *wr_addr = module_writable_address(mod, addr); |
| |
| - poison_endbr(addr+16, wr_addr, false); |
| + poison_endbr(addr + 16, wr_addr + 16, false); |
| } |
| } |
| |
| _ |
