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sections: global data can be in .bss
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When checking an address is located in a global data section also check
for the .bss section as global variables initialized to 0 can be in
there (-fzero-initialized-in-bss).

This was found when looking at ensure_safe_net_sysctl which was failing
to detect non-init sysctl pointing to a global data section when the
data was in the .bss section.

Signed-off-by: Antoine Tenart <atenart@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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atenart authored and davem330 committed Nov 22, 2021
1 parent e968b1b commit cb902b3
Showing 1 changed file with 10 additions and 4 deletions.
14 changes: 10 additions & 4 deletions include/asm-generic/sections.h
Original file line number Diff line number Diff line change
Expand Up @@ -130,18 +130,24 @@ static inline bool init_section_intersects(void *virt, size_t size)

/**
* is_kernel_core_data - checks if the pointer address is located in the
* .data section
* .data or .bss section
*
* @addr: address to check
*
* Returns: true if the address is located in .data, false otherwise.
* Returns: true if the address is located in .data or .bss, false otherwise.
* Note: On some archs it may return true for core RODATA, and false
* for others. But will always be true for core RW data.
*/
static inline bool is_kernel_core_data(unsigned long addr)
{
return addr >= (unsigned long)_sdata &&
addr < (unsigned long)_edata;
if (addr >= (unsigned long)_sdata && addr < (unsigned long)_edata)
return true;

if (addr >= (unsigned long)__bss_start &&
addr < (unsigned long)__bss_stop)
return true;

return false;
}

/**
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