Commit-ID: e363d24c2b997c421476c6aa00547edadf678efe Gitweb: http://git.kernel.org/tip/e363d24c2b997c421476c6aa00547edadf678efe Author: Mike Travis <[email protected]> AuthorDate: Mon, 1 Aug 2016 13:40:51 -0500 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 10 Aug 2016 15:55:38 +0200
x86/platform/UV: Fix bug with iounmap() of the UV4 EFI System Table causing a crash Save the uv_systab::size field before doing the iounmap() of the struct pointer, to avoid a NULL dereference crash. Tested-by: Frank Ramsay <[email protected]> Tested-by: John Estabrook <[email protected]> Signed-off-by: Mike Travis <[email protected]> Reviewed-by: Dimitri Sivanich <[email protected]> Reviewed-by: Nathan Zimmer <[email protected]> Cc: Alex Thorlton <[email protected]> Cc: Andrew Banman <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Russ Anderson <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/platform/uv/bios_uv.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c index 66b2166..4e9fd13 100644 --- a/arch/x86/platform/uv/bios_uv.c +++ b/arch/x86/platform/uv/bios_uv.c @@ -199,12 +199,14 @@ void uv_bios_init(void) return; } + /* Starting with UV4 the UV systab size is variable */ if (uv_systab->revision >= UV_SYSTAB_VERSION_UV4) { + int size = uv_systab->size; + iounmap(uv_systab); - uv_systab = ioremap(efi.uv_systab, uv_systab->size); + uv_systab = ioremap(efi.uv_systab, size); if (!uv_systab) { - pr_err("UV: UVsystab: ioremap(%d) failed!\n", - uv_systab->size); + pr_err("UV: UVsystab: ioremap(%d) failed!\n", size); return; } }
