diff options
| author | Helge Deller <deller@kernel.org> | 2025-11-26 21:15:04 +0100 |
|---|---|---|
| committer | Sasha Levin <sashal@kernel.org> | 2026-03-04 07:20:40 -0500 |
| commit | 47e351dfef60ab0e3285133556e1a9c7f646a969 (patch) | |
| tree | 362ebc1e6814262f335ec0b656a5330fb3432809 /security | |
| parent | ec737e7fdf2f0ba7b203d4ec72cc915978b10e7e (diff) | |
apparmor: Fix & Optimize table creation from possibly unaligned memory
[ Upstream commit 6fc367bfd4c8886e6b1742aabbd1c0bdc310db3a ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'security')
| -rw-r--r-- | security/apparmor/include/match.h | 12 | ||||
| -rw-r--r-- | 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 ae31a8a631fc..dfc93631b43d 100644 --- a/security/apparmor/include/match.h +++ b/security/apparmor/include/match.h @@ -102,16 +102,18 @@ struct aa_dfa { struct table_header *tables[YYTD_ID_TSIZE]; }; -#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 4f998715d294..fae26953619a 100644 --- a/security/apparmor/match.c +++ b/security/apparmor/match.c @@ -67,14 +67,13 @@ 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 |