[ARM] 5340/1: fix stack placement after noexecstack changes
Commit 8ec53663 ("[ARM] Improve non-executable support") added support for detecting non-executable stack binaries. One of the things it does is to make READ_IMPLIES_EXEC be set in ->personality if we are running on a CPU that doesn't support the XN ("Execute Never") page table bit or if we are running a binary that needs an executable stack. This exposed a latent bug in ARM's asm/processor.h due to which we'll end up placing the stack at a very low address, where it will bump into the heap on any application that uses significant amount of stack or heap or both, causing many interesting crashes. Fix this by testing the ADDR_LIMIT_32BIT bit in ->personality instead of testing for equality against PER_LINUX_32BIT. Reviewed-by: NNicolas Pitre <nico@marvell.com> Signed-off-by: NLennert Buytenhek <buytenh@marvell.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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