From: Darrick J. Wong Date: Tue, 21 Oct 2025 18:29:56 +0000 (-0700) Subject: xfs: don't set bt_nr_sectors to a negative number X-Git-Tag: v6.18-rc3~13^2~3 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=bd721ec7dedcc24ced51559e42a39140b59dfd08;p=thirdparty%2Flinux.git xfs: don't set bt_nr_sectors to a negative number xfs_daddr_t is a signed type, which means that xfs_buf_map_verify is using a signed comparison. This causes problems if bt_nr_sectors is never overridden (e.g. in the case of an xfbtree for rmap btree repairs) because even daddr 0 can't pass the verifier test in that case. Define an explicit max constant and set the initial bt_nr_sectors to a positive value. Found by xfs/422. Cc: stable@vger.kernel.org # v6.18-rc1 Fixes: 42852fe57c6d2a ("xfs: track the number of blocks in each buftarg") Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Carlos Maiolino --- diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 773d959965dc..47edf3041631 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -1751,7 +1751,7 @@ xfs_init_buftarg( const char *descr) { /* The maximum size of the buftarg is only known once the sb is read. */ - btp->bt_nr_sectors = (xfs_daddr_t)-1; + btp->bt_nr_sectors = XFS_BUF_DADDR_MAX; /* Set up device logical sector size mask */ btp->bt_logical_sectorsize = logical_sectorsize; diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h index 8fa7bdf59c91..e25cd2a160f3 100644 --- a/fs/xfs/xfs_buf.h +++ b/fs/xfs/xfs_buf.h @@ -22,6 +22,7 @@ extern struct kmem_cache *xfs_buf_cache; */ struct xfs_buf; +#define XFS_BUF_DADDR_MAX ((xfs_daddr_t) S64_MAX) #define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL)) #define XBF_READ (1u << 0) /* buffer intended for reading from device */