KASan uses constructors for initializing redzones for global variables.
Globals instrumentation in GCC 4.9.2 produces constructors with priority
(.init_array.00099)
Currently kernel ignores such constructors. Only constructors with
default priority supported (.init_array)
This patch adds support for constructors with priorities. For kernel
image we put pointers to constructors between __ctors_start/__ctors_end
and do_ctors() will call them on start up. For modules we merge
.init_array.* sections into resulting .init_array. Module code properly
handles constructors in .init_array section.
Signed-off-by: Andrey Ryabinin <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Konstantin Serebryany <[email protected]>
Cc: Dmitry Chernenkov <[email protected]>
Signed-off-by: Andrey Konovalov <[email protected]>
Cc: Yuri Gribov <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
These __ksymtab*/__kcrctab* sections currently have non-zero addresses.
Non-zero section addresses in a relocatable ELF confuse GDB and it ends
up not relocating all symbols when add-symbol-file is used on modules
which have exports. The kernel's module loader does not care about
these addresses, so let's just set them to zero.
Before:
$ readelf -S lib/notifier-error-inject.ko | grep 'Name\| __ksymtab_gpl'
[Nr] Name Type Addr Off Size ES Flg Lk Inf Al
[ 8] __ksymtab_gpl PROGBITS 0000000c 0001b4 000010 00 A 0 0 4
(gdb) add-symbol-file lib/notifier-error-inject.ko 0x500000 -s .bss 0x700000
add symbol table from file "lib/notifier-error-inject.ko" at
.text_addr = 0x500000
.bss_addr = 0x700000
(gdb) p ¬ifier_err_inject_dir
$3 = (struct dentry **) 0x0
After:
$ readelf -S lib/notifier-error-inject.ko | grep 'Name\| __ksymtab_gpl'
[Nr] Name Type Addr Off Size ES Flg Lk Inf Al
[ 8] __ksymtab_gpl PROGBITS 00000000 0001b4 000010 00 A 0 0 4
(gdb) add-symbol-file lib/notifier-error-inject.ko 0x500000 -s .bss 0x700000
add symbol table from file "lib/notifier-error-inject.ko" at
.text_addr = 0x500000
.bss_addr = 0x700000
(gdb) p ¬ifier_err_inject_dir
$3 = (struct dentry **) 0x700000
Signed-off-by: Rabin Vincent <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
This patch places every exported symbol in its own section
(i.e. "___ksymtab+printk"). Thus the linker will use its SORT() directive
to sort and finally merge all symbol in the right and final section
(i.e. "__ksymtab").
The symbol prefixed archs use an underscore as prefix for symbols.
To avoid collision we use a different character to create the temporary
section names.
This work was supported by a hardware donation from the CE Linux Forum.
Signed-off-by: Alessio Igor Bogani <[email protected]>
Signed-off-by: Rusty Russell <[email protected]> (folded in '+' fixup)
Tested-by: Dirk Behme <[email protected]>
Andrey Ryabinin