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| author | Steve Baird <baird@adacore.com> | 2020-01-17 22:10:13 -0800 |
|---|---|---|
| committer | Pierre-Marie de Rodat <derodat@adacore.com> | 2020-06-04 05:10:59 -0400 |
| commit | b5682bf40cedf95d1e0150c6a6ba7a64c59fd968 (patch) | |
| tree | 8a859c90f9b28e936ef5d91c4bbb5b8220a8a319 | |
| parent | b68c1670b7d40b09be2995e1e730ce4c87eb688c (diff) | |
| download | gcc-b5682bf40cedf95d1e0150c6a6ba7a64c59fd968.zip gcc-b5682bf40cedf95d1e0150c6a6ba7a64c59fd968.tar.gz gcc-b5682bf40cedf95d1e0150c6a6ba7a64c59fd968.tar.bz2 | |
[Ada] Avoid buffer overflow in Long_Long_Float_Text_IO
2020-06-04 Steve Baird <baird@adacore.com>
gcc/ada/
* libgnat/s-imgrea.ads: Declare a named number
Max_Real_Image_Length with value 5200. Provide a comment
explaining why this value was chosen.
* libgnat/s-imgrea.adb (Set_Image_Real): Increase the upper
bound of the local String variable Digs to
Max_Real_Image_Length.
* libgnat/a-tiflau.adb (Put): Increase the upper bound of the
local String variable Buf to Max_Real_Image_Length.
(Puts): Increase the upper bound of the local String variable
Buf to Max_Real_Image_Length.
| -rw-r--r-- | gcc/ada/libgnat/a-tiflau.adb | 4 | ||||
| -rw-r--r-- | gcc/ada/libgnat/s-imgrea.adb | 11 | ||||
| -rw-r--r-- | gcc/ada/libgnat/s-imgrea.ads | 5 |
3 files changed, 10 insertions, 10 deletions
diff --git a/gcc/ada/libgnat/a-tiflau.adb b/gcc/ada/libgnat/a-tiflau.adb index 25d78ca..214b5c8 100644 --- a/gcc/ada/libgnat/a-tiflau.adb +++ b/gcc/ada/libgnat/a-tiflau.adb @@ -194,7 +194,7 @@ package body Ada.Text_IO.Float_Aux is Aft : Field; Exp : Field) is - Buf : String (1 .. 3 * Field'Last + 2); + Buf : String (1 .. Max_Real_Image_Length); Ptr : Natural := 0; begin @@ -212,7 +212,7 @@ package body Ada.Text_IO.Float_Aux is Aft : Field; Exp : Field) is - Buf : String (1 .. 3 * Field'Last + 2); + Buf : String (1 .. Max_Real_Image_Length); Ptr : Natural := 0; begin diff --git a/gcc/ada/libgnat/s-imgrea.adb b/gcc/ada/libgnat/s-imgrea.adb index 642724b..68b1fdc 100644 --- a/gcc/ada/libgnat/s-imgrea.adb +++ b/gcc/ada/libgnat/s-imgrea.adb @@ -151,14 +151,9 @@ package body System.Img_Real is Scale : Integer; Expon : Integer; - Field_Max : constant := 255; - -- This should be the same value as Ada.[Wide_]Text_IO.Field'Last. - -- It is not worth dragging in Ada.Text_IO to pick up this value, - -- since it really should never be necessary to change it. - - Digs : String (1 .. 2 * Field_Max + 16); - -- Array used to hold digits of converted integer value. This is a - -- large enough buffer to accommodate ludicrous values of Fore and Aft. + Digs : String (1 .. Max_Real_Image_Length); + -- Array used to hold digits of converted integer value. This is a large + -- enough buffer to accommodate ludicrous Fore/Aft/Exp combinations. Ndigs : Natural; -- Number of digits stored in Digs (and also subscript of last digit) diff --git a/gcc/ada/libgnat/s-imgrea.ads b/gcc/ada/libgnat/s-imgrea.ads index 8adb623..9711516 100644 --- a/gcc/ada/libgnat/s-imgrea.ads +++ b/gcc/ada/libgnat/s-imgrea.ads @@ -73,4 +73,9 @@ package System.Img_Real is -- can be set to any valid values for the case of use from Text_IO. Note -- that no space is stored at the start for non-negative values. + Max_Real_Image_Length : constant := 5200; + -- If Exp is set to zero and Aft is set to Text_IO.Field'Last (i.e., 255) + -- then Long_Long_Float'Last generates an image whose length is + -- slightly less than 5200. + end System.Img_Real; |