History

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner: - Expand the space for uncompressing as the LZ4 worst case does not fit into the currently reserved space - Validate boot parameters more strictly to prevent out of bound access in the decompressor/boot code - Fix off by one errors in get_segment_base() * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Prevent faulty bootparams.screeninfo from causing harm x86/boot: Provide more slack space during decompression x86/ldt: Fix off by one in get_segment_base()

Linus Torvalds committed 9 years ago

Commit d0fa6ea2 parents 3b62dc6 fb1cc2f3 files · +10 −8Browse files

Unified · Split

3 files
  1. arch/x86/boot/compressed/misc.c +1 −2
  2. arch/x86/boot/header.S +7 −1
  3. arch/x86/events/core.c +2 −5
arch/x86/boot/compressed/misc.c+1−2
@@ -116,8 +116,7 @@ void __putstr(const char *s) · 115 unmodified lines
116116 }
117117 }
118118
119− if (boot_params->screen_info.orig_video_mode == 0 &&
120− lines == 0 && cols == 0)
119+ if (lines == 0 || cols == 0)
121120 return;
122121
123122 x = boot_params->screen_info.orig_x;
arch/x86/boot/header.S+7−1
@@ -520,8 +520,14 @@ pref_address: .quad LOAD_PHYSICAL_ADDR # preferred load addr · 519 unmodified lines
520520 # the description in lib/decompressor_xxx.c for specific information.
521521 #
522522 # extra_bytes = (uncompressed_size >> 12) + 65536 + 128
523+#
524+# LZ4 is even worse: data that cannot be further compressed grows by 0.4%,
525+# or one byte per 256 bytes. OTOH, we can safely get rid of the +128 as
526+# the size-dependent part now grows so fast.
527+#
528+# extra_bytes = (uncompressed_size >> 8) + 65536
523529
524−#define ZO_z_extra_bytes ((ZO_z_output_len >> 12) + 65536 + 128)
530+#define ZO_z_extra_bytes ((ZO_z_output_len >> 8) + 65536)
525531 #if ZO_z_output_len > ZO_z_input_len
526532 # define ZO_z_extract_offset (ZO_z_output_len + ZO_z_extra_bytes - \
527533 ZO_z_input_len)
arch/x86/events/core.c+2−5
@@ -2335,12 +2335,9 @@ static unsigned long get_segment_base(unsigned int segment) · 2334 unmodified lines
23352335 #ifdef CONFIG_MODIFY_LDT_SYSCALL
23362336 struct ldt_struct *ldt;
23372337
2338− if (idx > LDT_ENTRIES)
2339− return 0;
2340−
23412338 /* IRQs are off, so this synchronizes with smp_store_release */
23422339 ldt = lockless_dereference(current->active_mm->context.ldt);
2343− if (!ldt || idx > ldt->nr_entries)
2340+ if (!ldt || idx >= ldt->nr_entries)
23442341 return 0;
23452342
23462343 desc = &ldt->entries[idx];
@@ -2348,7 +2345,7 @@ static unsigned long get_segment_base(unsigned int segment) · 1 unmodified line
23482345 return 0;
23492346 #endif
23502347 } else {
2351− if (idx > GDT_ENTRIES)
2348+ if (idx >= GDT_ENTRIES)
23522349 return 0;
23532350
23542351 desc = raw_cpu_ptr(gdt_page.gdt) + idx;