CVE-2021-47353

In the Linux kernel, the following vulnerability has been resolved: udf: Fix NULL pointer dereference in udf_symlink function In function udf_symlink, epos.bh is assigned with the value returned by udf_tgetblk. The function udf_tgetblk is defined in udf/misc.c and returns the value of sb_getblk function that could be NULL. Then, epos.bh is used without any check, causing a possible NULL pointer dereference when sb_getblk fails. This fix adds a check to validate the value of epos.bh.

• linux linux kernel (< 4.4.276) • linux linux kernel (>= 4.5 < 4.9.276) • linux linux kernel (>= 4.10 < 4.14.240) • linux linux kernel (>= 4.15 < 4.19.198) • linux linux kernel (>= 4.20 < 5.4.133) • linux linux kernel (>= 5.5 < 5.10.51) • linux linux kernel (>= 5.11 < 5.12.18) • linux linux kernel (>= 5.13 < 5.13.3)