Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: fbcon: fix NULL pointer dereference for a console without vc_data fbcon_new_modelist() runs when a framebuffer's modelist changes. For each console mapped to it with fb_display[i].mode set, it reads vc_cons[i].d and passes the vc_num to fbcon_set_disp(). This assumes a console with a mode set has a vc_data, but it can be NULL. fbcon_set_disp() sets fb_display[i].mode before it checks vc_data, and fbcon_deinit() leaves the mode set after the vc_data is freed. fbcon_new_modelist() then dereferences the NULL vc_data. Keep fb_display[i].mode set only while the console has a vc_data. Check vc_data before setting the mode in fbcon_set_disp(), and clear the mode in fbcon_deinit(). The existing mode check in fbcon_new_modelist() then skips such consoles.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected d1baa4ffa677bf6986c460fcfd4cdaf8bfe66f0e before 8e9b8b008f4036df0318870c5d754134ff1b94cc; affected d1baa4ffa677bf6986c460fcfd4cdaf8bfe66f0e before cc4382dc5134826a3936a6b08de17f7dc7abe232; affected d1baa4ffa677bf6986c460fcfd4cdaf8bfe66f0e before 9b783b7e03dc78ec102edf618259a2b55911fc6a; affected d1baa4ffa677bf6986c460fcfd4cdaf8bfe66f0e before ac970358c5ca0775841bd2a56ce15dc464b99003; affected d1baa4ffa677bf6986c460fcfd4cdaf8bfe66f0e before 6617df8c246311c82cebf061a4cee55b9df60922; affected d1baa4ffa677bf6986c460fcfd4cdaf8bfe66f0e before b134ad2f7c06b3c1098dcc95008e2045ff4b49b2; affected d1baa4ffa677bf6986c460fcfd4cdaf8bfe66f0e before 5fae9a928482d4845bca169a3a098789203a1ca4 |
| Linux / Linux | affected 2.6.23; unaffected 0 before 2.6.23; unaffected 5.15.212 through 5.15.*; unaffected 6.1.178 through 6.1.*; unaffected 6.6.145 through 6.6.*; unaffected 6.12.97 through 6.12.*; unaffected 6.18.40 through 6.18.*; unaffected 7.1.5 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/8e9b8b008f4036df0318870c5d754134ff1b94cc
- https://git.kernel.org/stable/c/cc4382dc5134826a3936a6b08de17f7dc7abe232
- https://git.kernel.org/stable/c/9b783b7e03dc78ec102edf618259a2b55911fc6a
- https://git.kernel.org/stable/c/ac970358c5ca0775841bd2a56ce15dc464b99003
- https://git.kernel.org/stable/c/6617df8c246311c82cebf061a4cee55b9df60922
- https://git.kernel.org/stable/c/b134ad2f7c06b3c1098dcc95008e2045ff4b49b2
- https://git.kernel.org/stable/c/5fae9a928482d4845bca169a3a098789203a1ca4