Andrey Ryabinin 8defb3367f ARM: 8320/1: fix integer overflow in ELF_ET_DYN_BASE ... Usually ELF_ET_DYN_BASE is 2/3 of TASK_SIZE. With 3G/1G user/kernel split this is not so, because 2*TASK_SIZE overflows 32 bits, so the actual value of ELF_ET_DYN_BASE is: (2 * TASK_SIZE / 3) = 0x2a000000 When ASLR is disabled PIE binaries will load at ELF_ET_DYN_BASE address. On 32bit platforms AddressSanitzer uses addresses [0x20000000 - 0x40000000] for shadow memory [1]. So ASan doesn't work for PIE binaries when ASLR disabled as it fails to map shadow memory. Also after Kees's 'split ET_DYN ASLR from mmap ASLR' patchset PIE binaries has a high chance of loading somewhere in between [0x2a000000 - 0x40000000] even if ASLR enabled. This makes ASan with PIE absolutely incompatible. Fix overflow by dividing TASK_SIZE prior to multiplying. After this patch ELF_ET_DYN_BASE equals to (for CONFIG_VMSPLIT_3G=y): (TASK_SIZE / 3 * 2) = 0x7f555554 [1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerAlgorithm#Mapping Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Reported-by: Maria Guseva <m.guseva@samsung.com> Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>		2015-03-28 15:46:29 +00:00
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asm	ARM: 8320/1: fix integer overflow in ELF_ET_DYN_BASE	2015-03-28 15:46:29 +00:00
debug	ARM: SoC platform changes	2015-02-17 09:27:54 -08:00
uapi/asm	Fairly small update, but there are some interesting new features.	2015-02-13 09:55:09 -08:00