Commit 4e310fda authored Apr 14, 2010 by Joe Perches Committed by Linus Torvalds Apr 14, 2010

vsprintf: Change struct printf_spec.precision from s8 to s16



Commit ef0658f3 changed precision
from int to s8.

There is existing kernel code that uses a larger precision.

An example from the audit code:
	vsnprintf(...,..., " msg='%.1024s'", (char *)data);
which overflows precision and truncates to nothing.

Extending precision size fixes the audit system issue.

Other changes:

Change the size of the struct printf_spec.type from u16 to u8 so
sizeof(struct printf_spec) stays as small as possible.
Reorder the struct members so sizeof(struct printf_spec) remains 64 bits
without alignment holes.
Document the struct members a bit more.

Original-patch-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 2ba3abd8

lib/vsprintf.c

+5 −5

Original line number	Diff line number	Diff line
		@@ -408,12 +408,12 @@ enum format_type {
		};

		struct printf_spec {
		u16 type;
		s16 field_width; /* width of output field */
		u8 type; /* format_type enum */
		u8 flags; /* flags to number() */
		u8 base;
		s8 precision; /* # of digits/chars */
		u8 qualifier;
		u8 base; /* number base, 8, 10 or 16 only */
		u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
		s16 field_width; /* width of output field */
		s16 precision; /* # of digits/chars */
		};

		static char number(char buf, char *end, unsigned long long num,

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