--- linux-2.6.33/scripts/mod/modpost.c~ 2010-02-24 19:52:17.000000000 +0100 +++ linux-2.6.33/scripts/mod/modpost.c 2010-03-07 14:26:47.242168558 +0100 @@ -15,7 +15,8 @@ #include #include #include "modpost.h" -#include "../../include/generated/autoconf.h" +// PLD architectures don't use CONFIG_SYMBOL_PREFIX +//#include "../../include/generated/autoconf.h" #include "../../include/linux/license.h" /* Some toolchains use a `_' prefix for all user symbols. */ --- linux-3.0/scripts/kconfig/lxdialog/check-lxdialog.sh~ 2011-07-22 04:17:23.000000000 +0200 +++ linux-3.0/scripts/kconfig/lxdialog/check-lxdialog.sh 2011-08-25 21:26:04.799150642 +0200 @@ -9,6 +9,12 @@ $cc -print-file-name=lib${lib}.${ext} | grep -q / if [ $? -eq 0 ]; then echo "-l${lib}" + for libt in tinfow tinfo ; do + $cc -print-file-name=lib${libt}.${ext} | grep -q / + if [ $? -eq 0 ]; then + echo "-l${libt}" + fi + done exit fi done From: Dave Chinner When we do dquot readahead in log recovery, we do not use a verifier as the underlying buffer may not have dquots in it. e.g. the allocation operation hasn't yet been replayed. Hence we do not want to fail recovery because we detect an operation to be replayed has not been run yet. This problem was addressed for inodes in commit d891400 ("xfs: inode buffers may not be valid during recovery readahead") but the problem was not recognised to exist for dquots and their buffers as the dquot readahead did not have a verifier. The result of not using a verifier is that when the buffer is then next read to replay a dquot modification, the dquot buffer verifier will only be attached to the buffer if *readahead is not complete*. Hence we can read the buffer, replay the dquot changes and then add it to the delwri submission list without it having a verifier attached to it. This then generates warnings in xfs_buf_ioapply(), which catches and warns about this case. Fix this and make it handle the same readahead verifier error cases as for inode buffers by adding a new readahead verifier that has a write operation as well as a read operation that marks the buffer as not done if any corruption is detected. Also make sure we don't run readahead if the dquot buffer has been marked as cancelled by recovery. This will result in readahead either succeeding and the buffer having a valid write verifier, or readahead failing and the buffer state requiring the subsequent read to resubmit the IO with the new verifier. In either case, this will result in the buffer always ending up with a valid write verifier on it. Note: we also need to fix the inode buffer readahead error handling to mark the buffer with EIO. Brian noticed the code I copied from there wrong during review, so fix it at the same time. Add comments linking the two functions that handle readahead verifier errors together so we don't forget this behavioural link in future. cc: # 3.12 - current Signed-off-by: Dave Chinner Reviewed-by: Brian Foster Signed-off-by: Dave Chinner --- fs/xfs/libxfs/xfs_dquot_buf.c | 36 ++++++++++++++++++++++++++++++------ fs/xfs/libxfs/xfs_inode_buf.c | 2 ++ fs/xfs/libxfs/xfs_quota_defs.h | 2 +- fs/xfs/libxfs/xfs_shared.h | 1 + fs/xfs/xfs_log_recover.c | 9 +++++++-- 5 files changed, 41 insertions(+), 9 deletions(-) diff --git a/fs/xfs/libxfs/xfs_dquot_buf.c b/fs/xfs/libxfs/xfs_dquot_buf.c index 11cefb2..3cc3cf7 100644 --- a/fs/xfs/libxfs/xfs_dquot_buf.c +++ b/fs/xfs/libxfs/xfs_dquot_buf.c @@ -54,7 +54,7 @@ xfs_dqcheck( xfs_dqid_t id, uint type, /* used only when IO_dorepair is true */ uint flags, - char *str) + const char *str) { xfs_dqblk_t *d = (xfs_dqblk_t *)ddq; int errs = 0; @@ -207,7 +207,8 @@ xfs_dquot_buf_verify_crc( STATIC bool xfs_dquot_buf_verify( struct xfs_mount *mp, - struct xfs_buf *bp) + struct xfs_buf *bp, + int warn) { struct xfs_dqblk *d = (struct xfs_dqblk *)bp->b_addr; xfs_dqid_t id = 0; @@ -240,8 +241,7 @@ xfs_dquot_buf_verify( if (i == 0) id = be32_to_cpu(ddq->d_id); - error = xfs_dqcheck(mp, ddq, id + i, 0, XFS_QMOPT_DOWARN, - "xfs_dquot_buf_verify"); + error = xfs_dqcheck(mp, ddq, id + i, 0, warn, __func__); if (error) return false; } @@ -256,7 +256,7 @@ xfs_dquot_buf_read_verify( if (!xfs_dquot_buf_verify_crc(mp, bp)) xfs_buf_ioerror(bp, -EFSBADCRC); - else if (!xfs_dquot_buf_verify(mp, bp)) + else if (!xfs_dquot_buf_verify(mp, bp, XFS_QMOPT_DOWARN)) xfs_buf_ioerror(bp, -EFSCORRUPTED); if (bp->b_error) @@ -264,6 +264,25 @@ xfs_dquot_buf_read_verify( } /* + * readahead errors are silent and simply leave the buffer as !done so a real + * read will then be run with the xfs_dquot_buf_ops verifier. See + * xfs_inode_buf_verify() for why we use EIO and ~XBF_DONE here rather than + * reporting the failure. + */ +static void +xfs_dquot_buf_readahead_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + + if (!xfs_dquot_buf_verify_crc(mp, bp) || + !xfs_dquot_buf_verify(mp, bp, 0)) { + xfs_buf_ioerror(bp, -EIO); + bp->b_flags &= ~XBF_DONE; + } +} + +/* * we don't calculate the CRC here as that is done when the dquot is flushed to * the buffer after the update is done. This ensures that the dquot in the * buffer always has an up-to-date CRC value. @@ -274,7 +293,7 @@ xfs_dquot_buf_write_verify( { struct xfs_mount *mp = bp->b_target->bt_mount; - if (!xfs_dquot_buf_verify(mp, bp)) { + if (!xfs_dquot_buf_verify(mp, bp, XFS_QMOPT_DOWARN)) { xfs_buf_ioerror(bp, -EFSCORRUPTED); xfs_verifier_error(bp); return; @@ -287,3 +306,8 @@ const struct xfs_buf_ops xfs_dquot_buf_ops = { .verify_write = xfs_dquot_buf_write_verify, }; +const struct xfs_buf_ops xfs_dquot_buf_ra_ops = { + + .verify_read = xfs_dquot_buf_readahead_verify, + .verify_write = xfs_dquot_buf_write_verify, +}; diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c index ff17c48..1aabfda 100644 --- a/fs/xfs/libxfs/xfs_inode_buf.c +++ b/fs/xfs/libxfs/xfs_inode_buf.c @@ -68,6 +68,8 @@ xfs_inobp_check( * recovery and we don't get unnecssary panics on debug kernels. We use EIO here * because all we want to do is say readahead failed; there is no-one to report * the error to, so this will distinguish it from a non-ra verifier failure. + * Changes to this readahead error behavour also need to be reflected in + * xfs_dquot_buf_readahead_verify(). */ static void xfs_inode_buf_verify( diff --git a/fs/xfs/libxfs/xfs_quota_defs.h b/fs/xfs/libxfs/xfs_quota_defs.h index 1b0a083..f51078f 100644 --- a/fs/xfs/libxfs/xfs_quota_defs.h +++ b/fs/xfs/libxfs/xfs_quota_defs.h @@ -153,7 +153,7 @@ typedef __uint16_t xfs_qwarncnt_t; #define XFS_QMOPT_RESBLK_MASK (XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_RES_RTBLKS) extern int xfs_dqcheck(struct xfs_mount *mp, xfs_disk_dquot_t *ddq, - xfs_dqid_t id, uint type, uint flags, char *str); + xfs_dqid_t id, uint type, uint flags, const char *str); extern int xfs_calc_dquots_per_chunk(unsigned int nbblks); #endif /* __XFS_QUOTA_H__ */ diff --git a/fs/xfs/libxfs/xfs_shared.h b/fs/xfs/libxfs/xfs_shared.h index 5be5297..15c3ceb 100644 --- a/fs/xfs/libxfs/xfs_shared.h +++ b/fs/xfs/libxfs/xfs_shared.h @@ -49,6 +49,7 @@ extern const struct xfs_buf_ops xfs_inobt_buf_ops; extern const struct xfs_buf_ops xfs_inode_buf_ops; extern const struct xfs_buf_ops xfs_inode_buf_ra_ops; extern const struct xfs_buf_ops xfs_dquot_buf_ops; +extern const struct xfs_buf_ops xfs_dquot_buf_ra_ops; extern const struct xfs_buf_ops xfs_sb_buf_ops; extern const struct xfs_buf_ops xfs_sb_quiet_buf_ops; extern const struct xfs_buf_ops xfs_symlink_buf_ops; diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index c5ecaac..5991cdc 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -3204,6 +3204,7 @@ xlog_recover_dquot_ra_pass2( struct xfs_disk_dquot *recddq; struct xfs_dq_logformat *dq_f; uint type; + int len; if (mp->m_qflags == 0) @@ -3224,8 +3225,12 @@ xlog_recover_dquot_ra_pass2( ASSERT(dq_f); ASSERT(dq_f->qlf_len == 1); - xfs_buf_readahead(mp->m_ddev_targp, dq_f->qlf_blkno, - XFS_FSB_TO_BB(mp, dq_f->qlf_len), NULL); + len = XFS_FSB_TO_BB(mp, dq_f->qlf_len); + if (xlog_peek_buffer_cancelled(log, dq_f->qlf_blkno, len, 0)) + return; + + xfs_buf_readahead(mp->m_ddev_targp, dq_f->qlf_blkno, len, + &xfs_dquot_buf_ra_ops); } STATIC void -- 2.5.0 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs From 8358b02bf67d3a5d8a825070e1aa73f25fb2e4c7 Mon Sep 17 00:00:00 2001 From: Jann Horn Date: Tue, 26 Apr 2016 22:26:26 +0200 Subject: bpf: fix double-fdput in replace_map_fd_with_map_ptr() When bpf(BPF_PROG_LOAD, ...) was invoked with a BPF program whose bytecode references a non-map file descriptor as a map file descriptor, the error handling code called fdput() twice instead of once (in __bpf_map_get() and in replace_map_fd_with_map_ptr()). If the file descriptor table of the current task is shared, this causes f_count to be decremented too much, allowing the struct file to be freed while it is still in use (use-after-free). This can be exploited to gain root privileges by an unprivileged user. This bug was introduced in commit 0246e64d9a5f ("bpf: handle pseudo BPF_LD_IMM64 insn"), but is only exploitable since commit 1be7f75d1668 ("bpf: enable non-root eBPF programs") because previously, CAP_SYS_ADMIN was required to reach the vulnerable code. (posted publicly according to request by maintainer) Signed-off-by: Jann Horn Signed-off-by: Linus Torvalds Acked-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- kernel/bpf/verifier.c | 1 - 1 file changed, 1 deletion(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 618ef77..db2574e 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2030,7 +2030,6 @@ static int replace_map_fd_with_map_ptr(struct verifier_env *env) if (IS_ERR(map)) { verbose("fd %d is not pointing to valid bpf_map\n", insn->imm); - fdput(f); return PTR_ERR(map); } -- cgit v0.12