diff options
| author | Linn Crosetto <linn@hp.com> | 2013-08-13 15:46:41 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-10-18 07:45:48 -0700 |
| commit | 954acd2b6df732230608d260779ef6d545534929 (patch) | |
| tree | 5a46fc2d9d42dcae16b997c5984a6ec165111b99 /arch/x86/kernel/e820.c | |
| parent | 3232569ecd21ad181bd070acdb27ac5ccd54494c (diff) | |
x86: avoid remapping data in parse_setup_data()
commit 30e46b574a1db7d14404e52dca8e1aa5f5155fd2 upstream.
Type SETUP_PCI, added by setup_efi_pci(), may advertise a ROM size
larger than early_memremap() is able to handle, which is currently
limited to 256kB. If this occurs it leads to a NULL dereference in
parse_setup_data().
To avoid this, remap the setup_data header and allow parsing functions
for individual types to handle their own data remapping.
Signed-off-by: Linn Crosetto <linn@hp.com>
Link: http://lkml.kernel.org/r/1376430401-67445-1-git-send-email-linn@hp.com
Acked-by: Yinghai Lu <yinghai@kernel.org>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/kernel/e820.c')
| -rw-r--r-- | arch/x86/kernel/e820.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index d32abeabbda..174da5fc5a7 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -658,15 +658,18 @@ __init void e820_setup_gap(void) * boot_params.e820_map, others are passed via SETUP_E820_EXT node of * linked list of struct setup_data, which is parsed here. */ -void __init parse_e820_ext(struct setup_data *sdata) +void __init parse_e820_ext(u64 phys_addr, u32 data_len) { int entries; struct e820entry *extmap; + struct setup_data *sdata; + sdata = early_memremap(phys_addr, data_len); entries = sdata->len / sizeof(struct e820entry); extmap = (struct e820entry *)(sdata->data); __append_e820_map(extmap, entries); sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); + early_iounmap(sdata, data_len); printk(KERN_INFO "e820: extended physical RAM map:\n"); e820_print_map("extended"); } |