diff options
| author | Andrew Morton <akpm@osdl.org> | 2005-06-21 17:16:51 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-06-21 19:07:38 -0700 |
| commit | f2966632a134e865db3c819346a1dc7d96e05309 (patch) | |
| tree | 7285849b32f99b40de71e647366f1703a612e2c2 /fs/isofs | |
| parent | 642217c17b9a56c7e4cf48f6a13dfd5e4a4c2e10 (diff) | |
| download | lwn-f2966632a134e865db3c819346a1dc7d96e05309.tar.gz lwn-f2966632a134e865db3c819346a1dc7d96e05309.zip | |
[PATCH] rock: handle directory overflows
Handle the case where the variable-sized part of a rock-ridge directory entry
overhangs the end of the buffer which we allocated for it.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/isofs')
| -rw-r--r-- | fs/isofs/rock.c | 76 |
1 files changed, 74 insertions, 2 deletions
diff --git a/fs/isofs/rock.c b/fs/isofs/rock.c index 9a81830abff8..4326cb47f8fa 100644 --- a/fs/isofs/rock.c +++ b/fs/isofs/rock.c @@ -127,6 +127,66 @@ out: } /* + * We think there's a record of type `sig' at rs->chr. Parse the signature + * and make sure that there's really room for a record of that type. + */ +static int rock_check_overflow(struct rock_state *rs, int sig) +{ + int len; + + switch (sig) { + case SIG('S', 'P'): + len = sizeof(struct SU_SP_s); + break; + case SIG('C', 'E'): + len = sizeof(struct SU_CE_s); + break; + case SIG('E', 'R'): + len = sizeof(struct SU_ER_s); + break; + case SIG('R', 'R'): + len = sizeof(struct RR_RR_s); + break; + case SIG('P', 'X'): + len = sizeof(struct RR_PX_s); + break; + case SIG('P', 'N'): + len = sizeof(struct RR_PN_s); + break; + case SIG('S', 'L'): + len = sizeof(struct RR_SL_s); + break; + case SIG('N', 'M'): + len = sizeof(struct RR_NM_s); + break; + case SIG('C', 'L'): + len = sizeof(struct RR_CL_s); + break; + case SIG('P', 'L'): + len = sizeof(struct RR_PL_s); + break; + case SIG('T', 'F'): + len = sizeof(struct RR_TF_s); + break; + case SIG('Z', 'F'): + len = sizeof(struct RR_ZF_s); + break; + default: + len = 0; + break; + } + len += offsetof(struct rock_ridge, u); + if (len > rs->len) { + printk(KERN_NOTICE "rock: directory entry would overflow " + "storage\n"); + printk(KERN_NOTICE "rock: sig=0x%02x, size=%d, remaining=%d\n", + sig, len, rs->len); + return -EIO; + } + return 0; +} + +/* * return length of name field; 0: not found, -1: to be ignored */ int get_rock_ridge_filename(struct iso_directory_record *de, @@ -152,10 +212,12 @@ repeat: if (rr->len < 3) goto out; /* Something got screwed up here */ sig = isonum_721(rs.chr); + if (rock_check_overflow(&rs, sig)) + goto eio; rs.chr += rr->len; rs.len -= rr->len; if (rs.len < 0) - goto out; /* corrupted isofs */ + goto eio; /* corrupted isofs */ switch (sig) { case SIG('R', 'R'): @@ -213,6 +275,9 @@ repeat: out: kfree(rs.buffer); return ret; +eio: + ret = -EIO; + goto out; } static int @@ -245,10 +310,12 @@ repeat: if (rr->len < 3) goto out; /* Something got screwed up here */ sig = isonum_721(rs.chr); + if (rock_check_overflow(&rs, sig)) + goto eio; rs.chr += rr->len; rs.len -= rr->len; if (rs.len < 0) - goto out; /* corrupted isofs */ + goto eio; /* corrupted isofs */ switch (sig) { #ifndef CONFIG_ZISOFS /* No flag for SF or ZF */ @@ -479,6 +546,9 @@ repeat: out: kfree(rs.buffer); return ret; +eio: + ret = -EIO; + goto out; } static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit) @@ -618,6 +688,8 @@ repeat: if (rr->len < 3) goto out; /* Something got screwed up here */ sig = isonum_721(rs.chr); + if (rock_check_overflow(&rs, sig)) + goto out; rs.chr += rr->len; rs.len -= rr->len; if (rs.len < 0) |