Since '_parse_integer_limit()' (and so 'simple_strtoull()') is now
capable to handle overflow, adjust 'memparse()' to handle overflow
(denoted by ULLONG_MAX) returned from 'simple_strtoull()'. Also
use 'check_shl_overflow()' to catch an overflow possibly caused
by processing size suffix and denote it with ULLONG_MAX as well.

Signed-off-by: Dmitry Antipov <[email protected]>
---
v5: initial version to join the series
---
 lib/cmdline.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/lib/cmdline.c b/lib/cmdline.c
index 90ed997d9570..e18fdfb80ba5 100644
--- a/lib/cmdline.c
+++ b/lib/cmdline.c
@@ -151,38 +151,48 @@ unsigned long long memparse(const char *ptr, char 
**retptr)
 {
        char *endptr;   /* local pointer to end of parsed string */
 
+       unsigned int shl = 0;
        unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
 
+       /* Consume valid suffix even in case of overflow. */
        switch (*endptr) {
        case 'E':
        case 'e':
-               ret <<= 10;
+               shl += 10;
                fallthrough;
        case 'P':
        case 'p':
-               ret <<= 10;
+               shl += 10;
                fallthrough;
        case 'T':
        case 't':
-               ret <<= 10;
+               shl += 10;
                fallthrough;
        case 'G':
        case 'g':
-               ret <<= 10;
+               shl += 10;
                fallthrough;
        case 'M':
        case 'm':
-               ret <<= 10;
+               shl += 10;
                fallthrough;
        case 'K':
        case 'k':
-               ret <<= 10;
+               shl += 10;
                endptr++;
                fallthrough;
        default:
                break;
        }
 
+       /* If no overflow, apply suffix if any. */
+       if (likely(ret != ULLONG_MAX) && shl) {
+               unsigned long long val;
+
+               ret = (unlikely(check_shl_overflow(ret, shl, &val))
+                      ? ULLONG_MAX : val);
+       }
+
        if (retptr)
                *retptr = endptr;
 
-- 
2.52.0


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