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authorThomas Gleixner2008-02-27 20:57:40 +0100
committerIngo Molnar2008-04-17 17:40:51 +0200
commite3100c82abd9aa643dc15828202aceeae3504e03 (patch)
treedc4e1b69224a9e795fa9058dcc97c6e77cb71d4d /arch/x86/mm/ioremap.c
parentxen: make hvc0 the preferred console in domU (diff)
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x86: check physical address range in ioremap
Roland Dreier reported in http://lkml.org/lkml/2008/2/27/194 [ 8425.915139] BUG: unable to handle kernel paging request at ffffc20001a0a000 [ 8425.919087] IP: [<ffffffff8021dacc>] clflush_cache_range+0xc/0x25 [ 8425.919087] PGD 1bf80e067 PUD 1bf80f067 PMD 1bb497067 PTE 80000047000ee17b This is on a Intel machine with 36bit physical address space. The PTE entry references 47000ee000, which is outside of it. Add a check for the physical address space and warn/printk about the stupid caller. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/mm/ioremap.c')
-rw-r--r--arch/x86/mm/ioremap.c19
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 868bbde74698..17f518839028 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -35,6 +35,18 @@ unsigned long __phys_addr(unsigned long x)
}
EXPORT_SYMBOL(__phys_addr);
+static inline int phys_addr_valid(unsigned long addr)
+{
+ return addr < (1UL << boot_cpu_data.x86_phys_bits);
+}
+
+#else
+
+static inline int phys_addr_valid(unsigned long addr)
+{
+ return 1;
+}
+
#endif
int page_is_ram(unsigned long pagenr)
@@ -118,6 +130,13 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
if (!size || last_addr < phys_addr)
return NULL;
+ if (!phys_addr_valid(phys_addr)) {
+ printk(KERN_WARNING "ioremap: invalid physical address %lx\n",
+ phys_addr);
+ WARN_ON_ONCE(1);
+ return NULL;
+ }
+
/*
* Don't remap the low PCI/ISA area, it's always mapped..
*/