diff options
| author | Yu-Chun Lin <eleanor15x@gmail.com> | 2025-02-18 16:12:16 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-02-19 18:55:40 -0800 |
| commit | 606572eb22c1786a3957d24307f5760bb058ca19 (patch) | |
| tree | c61110f96d6b6dfb859ee15107392b9ae8807664 /net/sctp | |
| parent | 5bcd3d15ca13671fa7e221be38c8aed725630602 (diff) | |
sctp: Fix undefined behavior in left shift operation
According to the C11 standard (ISO/IEC 9899:2011, 6.5.7):
"If E1 has a signed type and E1 x 2^E2 is not representable in the result
type, the behavior is undefined."
Shifting 1 << 31 causes signed integer overflow, which leads to undefined
behavior.
Fix this by explicitly using '1U << 31' to ensure the shift operates on
an unsigned type, avoiding undefined behavior.
Signed-off-by: Yu-Chun Lin <eleanor15x@gmail.com>
Link: https://patch.msgid.link/20250218081217.3468369-1-eleanor15x@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/sctp')
| -rw-r--r-- | net/sctp/stream.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/sctp/stream.c b/net/sctp/stream.c index c241cc552e8d..bfcff6d6a438 100644 --- a/net/sctp/stream.c +++ b/net/sctp/stream.c @@ -735,7 +735,7 @@ struct sctp_chunk *sctp_process_strreset_tsnreq( * value SHOULD be the smallest TSN not acknowledged by the * receiver of the request plus 2^31. */ - init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1 << 31); + init_tsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map) + (1U << 31); sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL, init_tsn, GFP_ATOMIC); |