From: Helge Deller <deller@kernel.org> mainline inclusion from mainline-v7.0-rc1 commit 6fc367bfd4c8886e6b1742aabbd1c0bdc310db3a category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/15143 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Source blob may come from userspace and might be unaligned. Try to optize the copying process by avoiding unaligned memory accesses. - Added Fixes tag - Added "Fix &" to description as this doesn't just optimize but fixes a potential unaligned memory access Fixes: e6e8bf418850d ("apparmor: fix restricted endian type warnings for dfa unpack") Signed-off-by: Helge Deller <deller@gmx.de> [jj: remove duplicate word "convert" in comment trigger checkpatch warning] Signed-off-by: John Johansen <john.johansen@canonical.com> Conflicts: security/apparmor/include/match.h [Context conflicts.] Signed-off-by: Gu Bowen <gubowen5@huawei.com> --- security/apparmor/include/match.h | 12 +++++++----- security/apparmor/match.c | 7 +++---- 2 files changed, 10 insertions(+), 9 deletions(-) diff --git a/security/apparmor/include/match.h b/security/apparmor/include/match.h index 884489590588..e8fb2d70aef7 100644 --- a/security/apparmor/include/match.h +++ b/security/apparmor/include/match.h @@ -105,16 +105,18 @@ struct aa_dfa { extern struct aa_dfa *nulldfa; extern struct aa_dfa *stacksplitdfa; -#define byte_to_byte(X) (X) - #define UNPACK_ARRAY(TABLE, BLOB, LEN, TTYPE, BTYPE, NTOHX) \ do { \ typeof(LEN) __i; \ TTYPE *__t = (TTYPE *) TABLE; \ BTYPE *__b = (BTYPE *) BLOB; \ - for (__i = 0; __i < LEN; __i++) { \ - __t[__i] = NTOHX(__b[__i]); \ - } \ + BUILD_BUG_ON(sizeof(TTYPE) != sizeof(BTYPE)); \ + if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) \ + memcpy(__t, __b, (LEN) * sizeof(BTYPE)); \ + else /* copy & convert from big-endian */ \ + for (__i = 0; __i < LEN; __i++) { \ + __t[__i] = NTOHX(&__b[__i]); \ + } \ } while (0) static inline size_t table_size(size_t len, size_t el_size) diff --git a/security/apparmor/match.c b/security/apparmor/match.c index 2bac8e74f068..6124681321ad 100644 --- a/security/apparmor/match.c +++ b/security/apparmor/match.c @@ -111,14 +111,13 @@ static struct table_header *unpack_table(char *blob, size_t bsize) table->td_flags = th.td_flags; table->td_lolen = th.td_lolen; if (th.td_flags == YYTD_DATA8) - UNPACK_ARRAY(table->td_data, blob, th.td_lolen, - u8, u8, byte_to_byte); + memcpy(table->td_data, blob, th.td_lolen); else if (th.td_flags == YYTD_DATA16) UNPACK_ARRAY(table->td_data, blob, th.td_lolen, - u16, __be16, be16_to_cpu); + u16, __be16, get_unaligned_be16); else if (th.td_flags == YYTD_DATA32) UNPACK_ARRAY(table->td_data, blob, th.td_lolen, - u32, __be32, be32_to_cpu); + u32, __be32, get_unaligned_be32); else goto fail; /* if table was vmalloced make sure the page tables are synced -- 2.43.0