The branch main has been updated by mckusick:
URL:
https://cgit.FreeBSD.org/src/commit/?id=0eabe33087d8cb69ae800daae322f12a8f16bd10
commit 0eabe33087d8cb69ae800daae322f12a8f16bd10
Author: Kirk McKusick <mckus...@freebsd.org>
AuthorDate: 2023-03-07 22:59:56 +0000
Commit: Kirk McKusick <mckus...@freebsd.org>
CommitDate: 2023-03-07 23:02:19 +0000
Updates to UFS/FFS superblock integrity checks when reading a superblock.
Have to add a check that the computed cylinder group size does not
exceed the block size of the filesystem.
It is also necessary to validate additional parameters when a
superblock is going to be used in read-only mode if its supplementary
information is going to be read in to ensure that the size and
location of the supplementary information is valid. Also when a
warning is raised let it be accepted, but bound the flagged field
to the value checked by the warning.
No legitimate superblocks should fail as a result of these changes.
Reported by: Bob Prohaska, John-Mark Gurney, and Mark Millard
Tested by: Peter Holm
Reviewed by: Peter Holm
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38668
---
sys/ufs/ffs/ffs_subr.c | 38 ++++++++++++++++++++++++++++----------
1 file changed, 28 insertions(+), 10 deletions(-)
diff --git a/sys/ufs/ffs/ffs_subr.c b/sys/ufs/ffs/ffs_subr.c
index 0b462add0d05..1d4d98fcb67d 100644
--- a/sys/ufs/ffs/ffs_subr.c
+++ b/sys/ufs/ffs/ffs_subr.c
@@ -347,6 +347,8 @@ readsuper(void *devfd, struct fs **fsp, off_t sblockloc,
int flags,
#lhs, (intmax_t)lhs, #op, #rhs, (intmax_t)rhs, wmsg);\
if (error == 0) \
error = warnerr; \
+ if (warnerr == 0) \
+ lhs = rhs; \
}
#define FCHK2(lhs1, op1, rhs1, lhs2, op2, rhs2, fmt) \
if (lhs1 op1 rhs1 && lhs2 op2 rhs2) { \
@@ -360,16 +362,6 @@ readsuper(void *devfd, struct fs **fsp, off_t sblockloc,
int flags,
if (error == 0) \
error = ENOENT; \
}
-#define WCHK2(lhs1, op1, rhs1, lhs2, op2, rhs2, fmt) \
- if (lhs1 op1 rhs1 && lhs2 op2 rhs2) { \
- MPRINT("UFS%d superblock failed: %s (" #fmt ") %s %s (" \
- #fmt ") && %s (" #fmt ") %s %s (" #fmt ")%s\n", \
- fs->fs_magic == FS_UFS1_MAGIC ? 1 : 2, #lhs1, \
- (intmax_t)lhs1, #op1, #rhs1, (intmax_t)rhs1, #lhs2, \
- (intmax_t)lhs2, #op2, #rhs2, (intmax_t)rhs2, wmsg); \
- if (error == 0) \
- error = warnerr; \
- }
static int
validate_sblock(struct fs *fs, int flags)
@@ -408,6 +400,7 @@ validate_sblock(struct fs *fs, int flags)
} else if (fs->fs_magic == FS_UFS1_MAGIC) {
FCHK(fs->fs_sblockloc, <, 0, %jd);
FCHK(fs->fs_sblockloc, >, SBLOCK_UFS1, %jd);
+ FCHK(fs->fs_old_ncyl, !=, fs->fs_ncg, %jd);
}
FCHK(fs->fs_frag, <, 1, %jd);
FCHK(fs->fs_frag, >, MAXFRAG, %jd);
@@ -431,6 +424,30 @@ validate_sblock(struct fs *fs, int flags)
FCHK(fs->fs_sblkno, !=, roundup(
howmany(fs->fs_sblockloc + SBLOCKSIZE, fs->fs_fsize),
fs->fs_frag), %jd);
+ FCHK(CGSIZE(fs), >, fs->fs_bsize, %jd);
+ /* Only need to validate these if reading in csum data */
+ if ((flags & UFS_NOCSUM) != 0)
+ return (error);
+ FCHK((u_int64_t)fs->fs_ipg * fs->fs_ncg, >,
+ (((int64_t)(1)) << 32) - INOPB(fs), %jd);
+ FCHK(fs->fs_cstotal.cs_nifree, <, 0, %jd);
+ FCHK(fs->fs_cstotal.cs_nifree, >,
+ (u_int64_t)fs->fs_ipg * fs->fs_ncg, %jd);
+ FCHK(fs->fs_cstotal.cs_ndir, >,
+ ((u_int64_t)fs->fs_ipg * fs->fs_ncg) -
+ fs->fs_cstotal.cs_nifree, %jd);
+ FCHK(fs->fs_size, <, 8 * fs->fs_frag, %jd);
+ FCHK(fs->fs_size, <=, ((int64_t)fs->fs_ncg - 1) * fs->fs_fpg,
+ %jd);
+ FCHK(fs->fs_size, >, (int64_t)fs->fs_ncg * fs->fs_fpg, %jd);
+ FCHK(fs->fs_csaddr, <, 0, %jd);
+ FCHK(fs->fs_cssize, !=,
+ fragroundup(fs, fs->fs_ncg * sizeof(struct csum)), %jd);
+ FCHK(dtog(fs, fs->fs_csaddr), >, fs->fs_ncg, %jd);
+ FCHK(fs->fs_csaddr, <, cgdmin(fs, dtog(fs, fs->fs_csaddr)),
+ %jd);
+ FCHK(dtog(fs, fs->fs_csaddr + howmany(fs->fs_cssize,
+ fs->fs_fsize)), >, dtog(fs, fs->fs_csaddr), %jd);
return (error);
}
if (fs->fs_magic == FS_UFS2_MAGIC) {
@@ -511,6 +528,7 @@ validate_sblock(struct fs *fs, int flags)
FCHK(fs->fs_old_cgoffset, <, 0, %jd);
FCHK2(fs->fs_old_cgoffset, >, 0, ~fs->fs_old_cgmask, <, 0, %jd);
FCHK(fs->fs_old_cgoffset * (~fs->fs_old_cgmask), >, fs->fs_fpg, %jd);
+ FCHK(CGSIZE(fs), >, fs->fs_bsize, %jd);
/*
* If anything has failed up to this point, it is usafe to proceed
* as checks below may divide by zero or make other fatal calculations.
